Flint Rash Report

Attachment 7. ACE Rash Report

Flint Rash Investigation
A Report on Findings from Case Interviews, Water Testing,
and Dermatologic Screenings for Rashes that Developed
or Worsened after October 16, 2015

August 2016

Unified Coordination Group—Flint, Michigan
Michigan Department of Health and Human Services
U.S. Department of Health and Human Services
Centers for Disease Control and Prevention
Agency for Toxic Substances and Disease Registry
Office of the Assistant Secretary for Preparedness and Response
U.S. Environmental Protection Agency
Genesee County Health Department
Michigan Department of Environmental Quality

Flint Rash Investigation

A Report on Findings from Case Interviews, Water Testing, and Dermatologic
Screenings for Rashes that Developed or Worsened after October 16, 2015

Agency Unified Coordination Group—Flint, Michigan
Michigan Department of Health and Human Services

Centers for Disease Control and Prevention

Agency for Toxic Substances and Disease Registry

U.S. Environmental Protection Agency
U.S. Department of Health and Human Services

Genesee County Health Department

Michigan Department of Environmental Quality

August 2016

Acknowledgements
The county, state, and federal agencies that compose the Unified Coordination Group (UCG) acknowledge
the assistance offered in this investigation by the Genesee County Medical Society volunteer dermatologists:
Walter Barkey, MD; Robert Soderstrom, MD; Bishr Al Dabagh, MD; and Kevin Gaffney, MD. These physicians
devoted significant time to prepare for the clinical components of the investigation, carry out the
dermatological assessments, interpret the data, and importantly to help summarize the findings.
The UCG also thanks the residents of Flint for their enthusiastic response and participation in this
investigation. Finally, the report would not have been possible without the valuable input and feedback from
healthcare providers, community partners and organizations.

2

Table of Contents
List of Tables and Figures

……………………………………………….……………… 5

Executive Summary ………………………………………………………………………… 7

Section 1: Introduction

………………………………………………………………. 12

Background ……………………………………………………………………………………..
Timeline of Events
………………………………………………………………..
Introduction to Rash Illness
…………………………………………………….
Hair Loss ………………………………………………………………………………………..
Skin Conditions and Tap Water ……………………………………………………..
Objectives of this Investigation ……………………………………………………..

Section 2: Methods

12

12

13

14

15

15

………………………………………………………………………. 17

Identification of Individuals with Current and/or Worsening Rashes ..
Questionnaire
…………………………………………………………………………….
Collection and Analysis of Water Samples
………………………………
Dermatological Assessment
……………………………………………………..
Data Analysis -- Relationship between Water Quality and Rashes ……
Ethics Review
…………………………………………………………………………….

17

17

18

19

20

20

Section 3: Questionnaire Results ……………………………………………………… 21

Self-Reported Rash Characteristics
………………………………………….
Reported Changes in Water Quality and Use
………………………………
Medical Care
…………………………………………………………………………….
Summary of Questionnaire Data ……………………………………………………..

22

23

24

24

Section 4: Water Testing Results ……………………………………………………… 25

Metals
………………………………………………………………………………………..
Other Water Characteristics
…………..……………………………….……….
Disinfection Byproducts Sub-Study …………………………………………………
Aesthetic Water Quality …………………………………………………………………
Historic Conditions: Flint River Water …………………………………………
Summary of Water Sampling Data…………………………………………………..

25

25

28

28

28

29

3

Section 5: Dermatologic Assessments ……………………………………………...

31

Summary of Dermatologic Assessments ………………………………………….. 33

Section 6: Relationship between Water Quality and Rashes …………….. 35

Analysis of Water Quality and Rash Evaluation Conclusions ……………. 36

Section 7: Discussion, Recommendations and Next Steps………………….. 37

Limitations
……………………………………………………………………………. 38

Recommendations
………………………………………………………………… 39

Next Steps
……………………………………………………………………………. 39

References

……………………………………………..………………………………….. 41

Appendices

…………………………………………………………………………………. 45

A1. Flint Water Rash Response Flowchart ……………………………………..……. 45

A2. Review of Prior CDC/ATSDR Rash-Related Investigations………..………. 46

B1. Standardized Questionnaire …………………………………………………….... 47

B2. Flowchart of Individuals Participating in the Rash Investigation ……… 58

B3. Counts of Individuals Participating in Each Stage of the Investigation

by City Ward ………………………………………………………………………………………… 59

B4. Self-reported Rash Onset ……………………………………………………………….. 60

C1. Summary Statistics of Metal Concentrations in Residential Water ….. 61

C2. Summary Statistics of Water Quality Indicators in Residential Water.. 62

C3. Temporal Pattern of Total Hardness in Flint Water………………………….. 62

C4. Temporal Pattern of pH in Flint Water …………………………………………… 63

C5. Temporal Pattern of Chlorine Levels in Flint Water ……………………...… 63

C6. Summary of Other Metals Measured in Residential Water .………
64

C7. Potential Health Effects Associated with Exposure to Metals Detected

in Residential Water
…….…………………………………………………………..… 66

C8. Aesthetic or Cosmetic Issues Linked to Metals and Water Parameters.. 67

C9. Disinfection Byproducts and Other Organics Pilot Project
………. 68

C10. Summary of Comparison Values for Disinfection Byproducts in

Residential Drinking Water …………………………………………………………………. 71

D1. Dermatologic Assessment Form
…………………………………………. 73

D2. Dermatologic Diagnoses, by Category …………………………………………. 76

D3. Demographics: Interviews, Water Testing, and Dermatologic

Screening …………………………………………………..…………………………………….
78

D4. Tables of Dermatologic Data ………………………………………………………
79

4

E1. Description of Statistical Methods Used to Analyze Combined Data .. 81
E2. Clinical Categories for Rashes Not Possibly Related Versus Rashes
Possibly Related for Select Contaminants Detected Only ………………….. 81
E3. Average Concentrations for Select Contaminants comparing
Clinical Categories for Rashes Not Possibly Related Versus Rashes
Possibly Related …………………………………………………………………………….…… 82

List of Tables and Figures
Section 3: Questionnaire Results
Table 3-1. Source of Rash Referrals
…………………………………………………………………
Figure 3-1. Distribution of Referrals by Week
……………………………………………………
Table 3-2. Reported Pre-existing Medical Conditions
……………..……………….........
Table 3-3. Reported Metal Allergies
………………..……………………………………………….
Table 3-4. Frequency of Current Rash Symptoms …………………………………………………….
Table 3-5. Reported Changes in Water Source Used for Personal Care and Household
Activities
…………..……………………………………………….…………………………………………..

21
21
22
22
23
23

Section 4: Water Testing Results
Table 4-1. Summary of Detection Levels of Elements and Chemical Compounds that have been
Associated with Rashes or Other Skin Problems ……………………………………………….…..
27

Section 5: Dermatologic Assessments
Table 5-1. Dermatology Patient Demographics

…………………………………………….……..

Table 5-2. Dermatologist Diagnoses Classification Scheme ……………………………………

31
32

Appendices
Figure B3. Counts of Individuals Participating in Each Stage of the Investigation by
City Ward

………………….. ……………………………………………….………………………………………….

59

Figure B4. Self-reported Rash Onset ………………………………………………………………………….

60

Table C1. Summary Statistics of Metal Concentrations in Residential Water …………....

61

Table C2. Summary Statistics of Water Quality Indicators in Residential Water …….….

62

Figure C3. Temporal Pattern of Total Hardness in Flint Water

…………………….…..

62

Figure C4. Temporal Pattern of pH in Flint Water ……………………………….….……….……..

63

Figure C5. Temporal Pattern of Chlorine Levels in Flint Water

63

.…………….………….

Table C6. Summary of Other Metals Measured in Residential Water

……….…...

64

Table C7. Potential Health Effects Associated with Exposure to Metals Detected in
Residential Water

…………………………………….……………………………………………………..

66

Table C8. Aesthetic or Cosmetic Issues Linked to Metals and Water Parameters ….…..

67
5

Table C9-1. Summary of Trihalomethane Concentrations in Control and Rash Residences

69

Table C9-2. Summary of Haloacetic Acid Concentrations in Control and Rash Residences ..

69

Table C9-3. Summary of Haloacetonitrile Concentrations in Control and Rash Residences..

70

Table C10. Summary of Comparison Values for Disinfection Byproducts in Residential

Drinking Water ………………………………………………………………………………………………………………..

71

Table D2. Dermatologic Diagnoses, by Category

………………………………….……………………….

76

Table D3. Demographics: Interviews, Water Testing, and Dermatologic Screening …………..

78

Table D4-1. Severity of Rash for Each Clinical Category ……………………………………………………

79

Table D4-2. Racial and Temporal Distribution of Rash Clinical Category ………………………….

79

Table D4-3. Racial and Temporal Distribution of Rash Severity ………………………………………..

79

Table D4-4. Distribution of Recommended Topical Steroid Strength ……………………………….

80

Table E2. Comparison of Contaminant Water Concentrations for Different Clinical

Categories ……………………………………………………………………………………………………………..………..

81

Table E3. Average Concentrations for Select Contaminants comparing Clinical

Categories for Rashes Not Possibly Related Versus Rashes Possibly Related ….

82

6

Executive Summary
Background
On April 25, 2014 the City of Flint, Michigan switched its drinking water source from Lake Huron to the Flint
River. While the primary focus of public health response to the ensuing Flint Water Crisis has been on the
elevated lead levels resulting from the lack of corrosion control, general concerns about overall water quality
and whether the water was responsible for skin rashes have been major health concerns of Flint residents.
As part of the federal response to the Flint Water Crisis, the Unified Coordination Group (UCG), a
collaboration between local, state and federal health and environmental agencies lead by the US Department
of Health and Human Services (HHS), supported an investigation to assess whether Flint water might be
associated with the rashes experienced by some community residents.
Dermatitis and rash are general terms referring to inflammation of the top layer of the skin. Skin affected by
dermatitis may be red, itchy, scaly and dry. Sometimes fissures or cracks and rarely tiny blisters are present.
Dermatitis usually causes some degree of itching, which can be very intense at times and even cause burning
and stinging symptoms. Rashes are a common occurrence across the United States. While the incidence of
many rashes varies by countries and climates, the prevalence of the most common types of rash, atopic
dermatitis is estimated to be up to 20% in school aged children.
Correctly diagnosing rashes is complicated. The cause of most rashes is often multifactorial with many
contributing and exacerbating factors, including but not limited to environmental factors (e.g. ambient
humidity and temperature), exposure to irritants (e.g. soaps, chemicals) and dryness of skin. Many
conditions have a strong seasonal component, with most worsening in the winter (when the heat is turned
on and windows are closed) and improving in the summer. Almost all inflammatory skin conditions are
exacerbated by stress, both physical (e.g. contact with irritating chemicals) and psychological. Direct contact
with water that is hard and/or has high alkalinity, pH and chlorine has been associated in some scientific
studies with skin and eye irritation.
The objectives of the rash investigation were to better understand and characterize rash cases; explore
possible causes of the rashes and possible associations with the current Flint water supply; and make
recommendations for interventions.

Methods
The three investigative efforts undertaken by the UCG included:
1. A questionnaire/telephone survey of Flint residents reporting rashes and water quality concerns.
2. Clinical dermatologic evaluations for residents who agreed to be seen by one of four volunteer
dermatologists living in Flint or providing care for Flint-area residents.
3. Current water-quality testing for some survey respondents’ homes.
Investigating residence- specific past water quality was not possible as the investigation began after the city
returned to using Lake Huron water. To compensate for this, a review of historical water quality data
reported by the Flint water treatment plant was also conducted.
7

Results
Highlights of Questionnaire Results
Residents with rash concerns were identified through a variety of mechanisms, including physician referrals
and self-nomination.
• Of the 429 individuals who met case identification criteria, 390 were interviewed (90.9%).
• More respondents reported rash onset dates before October 2015 (56%; n=189 of 339) compared
with after October 2015 (44%; n=149 of 339).
• Among those who reported rash onset dates of
October 2015 and later, a majority (57%; n=85)
reported onsets in January and February of 2016.
Over 77% (n=296 of 383) of respondents
reported that they noticed changes (e.g., color,
odor, taste) in the tap water at the time their
symptoms began.
• Nearly 80% (n=296 of 371) of respondents
reported changing their showering or bathing
habits.

Case Identification
The investigation focused on rash-related
concerns associated with current water
quality. The case definition was a person
with Flint municipal water exposure
reporting a current or obviously worsening
rash with onset on or after October 16,
2015.

Highlights of Water Testing Results
• Water samples from 170 homes were collected and analyzed for a wide range of water-quality
issues, including metals and other parameters (e.g. hardness, pH), but the investigation focused on
metals and parameters associated with skin effects. (Note: results from one home were excluded
from the analysis due to their reported use of a private well and/or use of water treatment, thus
results presented in the report represent 169 homes).
• The water in some homes were found to have higher levels of metals (e.g. iron, aluminum,
manganese) that are known to have an adverse effect on the taste and coloration of the water. The
higher levels of these and some other metals in the water are likely the result of corrosion of water
service lines and/or internal plumbing due to inadequate corrosion control when the Flint River
served as the water source.
• The other metals and minerals that were detected in the water can generally be found in any water
system that uses surface water as a drinking water source, at levels that are generally similar to
levels reported from the City of Detroit system which uses Lake Huron as their source.
• Water samples were analyzed for metals that have been associated in some studies with either
allergic or irritant contact dermatitis. Arsenic, total chromium and silver levels were below the
lowest levels specified by drinking water regulations for all samples from all homes.
• Less than one percent of the samples exceeded the lowest drinking water regulations for copper and
nickel.
• A review of historic system water quality data from the period of time when Flint River water was
used as the source (April 2014–October 2015) demonstrated significant variability in water
hardness, pH/acidity, and free chlorine levels that could have played a role in skin and other irritant
health effects. During that time, pH, chlorine, and water hardness levels were all higher than they
were when measured for this study.
• Since a majority of rashes began while residents were using the Flint River water source, the
fluctuations in water quality during that time provide one possible explanation for a majority of the
eczema-related diagnoses made by the dermatologists. However, because water samples from the
8

homes of participants are not available for the Flint water source time period, confirmation of this is
not possible.

Highlights of Dermatologic Assessments Results
• Clinical dermatological assessments were provided for 122 residents.
• No presumptive or confirmed bacterial or viral infectious etiologies for rash were identified among
participants by the dermatologists.
• About 80% (n=97) of participants were classified as having current or resolved skin conditions
possibly related to water exposure. (See Appendix D for classification details.)
• Month or year of symptom onset was available for 89% of those clinically screened. Rashes with
onset after 2015 were more likely acute, less clinically severe and of limited duration. These rashes
were also more likely to be considered unrelated to water by the dermatologists (e.g. seborrheic
dermatitis). Respondents with rashes with onset before October 2015 tended to have chronic
diagnoses, such as eczema. The majority of respondents with those rashes stated their rash began
when the Flint River was being used as the water source.
• A subset of dermatology screening participants also had water quality testing results specific to their
residences. Current water quality data for those in the “definitely unrelated to water category” were
compared to the “possibly related”. Although a few metals were higher in homes of the possibly
related skin conditions, no levels were sufficiently high enough to be considered clinically significant.

Conclusions
This investigation documented 390 rash and 175 hair loss complaints, with the majority of participants
reporting changes in water quality when symptoms began. The proportion of participants evaluated by
dermatologists with clinically severe presentation of rash was higher among those with onset before October
2015. The types of metals and minerals detected in participant’s homes can generally be found in any water
systems that use surface water as their drinking water source. No specific contaminant or group of
contaminants in the water samples collected suggest a primary causal factor associated with rashes.
However, during the time when corrosion control was inadequate (before October 2015), and for a period of
time afterwards, some metals concentrations may have been higher. However, historic data on such a wide
spectrum of metals is not available from either individual homes or the water treatment plant for that time
period. Limited historic water sampling data for that period from the Flint water treatment plant suggests
very different water quality parameters (e.g., higher levels of chlorine, pH, and water hardness) compared
with treatment plant data after October 2015. These factors could have played a role in the development of
skin irritation or rashes among some participants.
Access to drinkable and useable water is an important quality of life consideration. Survey results and
dermatological histories demonstrated the direct (e.g., rash related symptoms) and indirect (e.g., changes in
the use of water for bathing, showering, or drinking) impact.
While we were unable to find a consistent pattern relative to the rashes and current water quality, our
findings were limited by the lack of historical data. One plausible hypothesis, however, is that conditions
present during the period when water was sourced from the Flint River (e.g. variable pH, hardness, and
chlorine levels) could have triggered skin irritation, dryness and rashes for a subset of susceptible individuals.
Further, these conditions could have been exacerbated by a variety of factors, including seasonal household
9

conditions (e.g. the heat being on with windows closed in the winter), self-care practices (e.g. use of some
lotions and creams), and fear and anxiety associated with the water crisis overall. Unfortunately, the lack of
historical data on either rash patterns in the community or residence- specific water samples from that time
period make drawing definitive conclusions impossible.
The findings have several limitations, including lack of residence specific historic water-sampling data;
exclusion of rash cases that did not worsen after October 16, 2015; of the 429 individuals that participated in
the interview survey and offered a dermatological screening, 122 were seen by dermatologists for
confirmatory diagnosis versus self-reported symptoms; and the complex relationship between the interaction
of genetic and environmental factors that can cause rashes, irrespective of water concerns. Participation in
the investigation was voluntary and is not generalizable to the larger Flint population. A comparison
population from a similar sized city that did not experience corrosion of municipal water plumbing
infrastructure was not available to establish a baseline of information on occurrence of rash.

Recommendations and Next Steps
Recommendations
Certain types of dermatitis can be difficult to resolve. However, most rashes are readily treatable. Residents
who have persistent rashes are urged to seek medical care, either from their primary care provider or from a
dermatologist. Fortunately, almost all Flint residents are covered by, or have access to, health insurance. In
addition, there are two federally qualified health centers that can provide care to all Flint residents,
regardless of background or ability to pay for care. Medicaid eligibility has been expanded, and additional
resources have been made available to the federally qualified health centers to ensure that all Flint residents
have access to care, including for investigation of rashes. Behavioral health services are also available for
residents with symptoms related to stress and anxiety, which, as noted in this report, are quite common.
In light of the results of this investigation, the following recommendations are provided for individuals:
1. If you have a rash or are concerned that you may have a metal allergy, schedule an appointment with
your primary care provider for evaluation, treatment, or referral to a specialists such as a dermatologist
or allergist.
2. Take care of your skin, particularly if it is sensitive. Follow the tips from local dermatologists:
http://www.michigan.gov/documents/flintwateDos_and_Donts_of_Rashes_Dr_Barkey_Final_530621_
7.pdf
3. If water in your home is discolored or has an unusual odor, flush water until the discoloration disappears.
If you want your water tested, contact the City of Flint or the MDEQ.
4. Flint residents are encouraged to discuss any adaptive strategies with their healthcare providers, , such
as changes in showering frequency or source of water, changes in showering products, and general skin
care changes.

10

Next Steps
1. MDHHS will conduct follow up interviews of study participants who received dermatologic screening
assessments to determine whether participants received treatments recommended by dermatologists,
the status of rash complaints, and the effect of re-exposure to municipal water following resolution of
rash.
2. MDHHS will work with the Genesee County Medical Society volunteer dermatologists to provide
guidance to primary care physicians on diagnosis and effective management strategies for the types of
rashes most commonly diagnosed among study participants. This will build upon general guidance on the
role of primary care physicians in the treatment of eczema that was provided by the dermatologists to
the primary care physicians of study participants who were diagnosed with eczematous dermatitis.
MDHHS and the dermatologists will continue working with the Genesee County Medical Society and
expanding outreach to include the Greater Flint Health Coalition and the Genesee County Osteopathic
Society.
3. Complete results of this investigation will be posted by MDHHS online at
http://www.michigan.gov/flintwater. It will also be posted online by the Agency for Toxic Substances
and Disease Registry.
4. MDHHS will continue ongoing surveillance of rash and other related health complaints in Flint by
monitoring trends in patient-reported data from Genesee County emergency departments via the
Michigan Syndromic Surveillance System (MSSS). Further review of Flint municipal water data from
periods before, during, and after the Flint River served as the municipal water source, in comparison to
data from MSSS and the Michigan Medicaid program will help provide further insight into potential
water quality changes temporally associated with rash.
5. EPA will continue to monitor the status of the Flint Water system.
6. The Department of Health and Human Services, including CDC/ATSDR, will continue to work with the
MDHHS to monitor health issues of Flint residents that may be related to the water system.

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Section 1: Introduction
Background
On April 25, 2014, the City of Flint switched water sources from the Detroit Water and Sewerage Department
(DWSD) to the Flint River. Ultimately, the lack of corrosion control resulted in elevated lead levels in drinking
water, and these elevated levels and their health consequences have been the primary focus of the public
health response. However, soon after the switch in water sources, Flint-area residents began reporting
broader concerns about water quality and skin rashes. Over time, the skin rash concerns became a major
concern to the community. The study reported here was conducted in response to those concerns.

Timeline of Events
This short synopsis of events following the water switch outlines key events related to the water system that
may be relevant to the community concerns about rashes. As mentioned above, on April 25, 2014, the City
of Flint switched water sources from the Detroit Water and Sewerage Department to the Flint River. In
August and September of 2014, the City of Flint issued boil-water advisories due to violations of total
coliform and Escherichia coli (E. coli) levels in the water distribution system. Subsequently, the city increased
the chlorine added at the water treatment plant and flushed the water distribution system; however,
corrosion controls were not implemented. In December 2014, the city was found to be in violation of a U.S.
Environmental Protection Agency (EPA) regulation regarding the disinfection byproduct, total
trihalomethanes (TTHM). Blood lead levels (BLL) in Flint were found to be elevated, particularly in children
(Hanna-Attisha 2016; CDC 2016), and an analysis of water samples detected elevated lead in the residential
tap water (EPA 2016a, State of Michigan 2016).
In an effort to mitigate the corrosion and consequent adverse health effects, the City of Flint returned to
buying water from DWSD on October 16, 2015. However, residents continued to report new or worsening
rashes as well as hair loss even after the switch back to DWSD water, raising significant concern among Flint
residents.
During the time that Flint municipal water was fed by the Flint River, the system experienced substantial
variations in water quality parameters (e.g., pH, hardness, alkalinity, and chlorine). There is some evidence
from the scientific literature of an association with skin and eye irritation and these parameters (Perkin,
2016; McNally, 1998; Miyake, 2004; Arnedo-Penn, 2007).
Since the transition back to the supply by DWSD on October 16, 2015, the water has continued to be closely
monitored and has shown substantial reductions in variability in water quality parameters, and now has a
water-quality composition comparable to other municipalities in the State of Michigan.
While the initial public health response was focused on lead, rash and other dermatological conditions such
as hair loss have been identified by Flint residents as one of most concerning health problem associated with
the Flint water crisis. A recent household survey demonstrated that 51% of households reported feeling that
the physical health of at least one member has worsened due to the Flint water crisis. Of those, 23.5%
12

reported skin rashes or irritation as the health condition (DHHS/CDC, 2016). Flint residents remain distrustful
of the water supply, with a majority of residents reporting being fearful of the water supply and feeling that
the problems will not be fixed, and the general public continues to report anxiety and mistrust regarding the
Flint water situation and its impact on their daily lives. In that same survey, participants reported that they
considered bottled water a much safer source for drinking and cooking compared with filtered tap water
(DHHS/CDC, 2016).

Introduction to Rash Illness
Dermatitis and rash are general terms referring to inflammation of the top layer of skin. Skin affected by
dermatitis may be red, scaly, and dry. Sometimes fissures or cracks and rarely tiny blisters are present. If
these features are present for weeks, the skin may become hyper pigmented (darker) and acquire a leathery
feel. Dermatitis usually causes some degree of itching, which can be very intense at times and can even cause
burning and stinging symptoms. Because rash (or dermatitis) is not a reportable condition in the State of
Michigan unless it is a manifestation of a reportable disease, the baseline prevalence of rash in Michigan and
in Flint is unknown. Chief complaint data from emergency departments across Michigan show that the 5-year
weekly average of rash-related visits is 19.4 and 19.2 visits per 1,000 visits for Flint and the State of Michigan,
respectively (MSSS, 2016).
Rashes are common. According to the National Institutes of Health, atopic dermatitis affects up to 30% of
people in the United States (NIH, 2013). Correctly diagnosing and classifying rashes is complicated. The
etiology of most rashes is often multifactorial with many contributing and exacerbating factors, including but
not limited to environmental factors (e.g., ambient humidity and temperature), exposure to irritants (e.g.,
soaps, chemicals), allergic predisposition, and dryness of skin. Many conditions such as atopic dermatitis,
eczematous dermatitis, and even psoriasis have a strong seasonal component, with most worsening in the
winter (when the heat is turned on and the windows are closed) and improving in the summer (Dr. Walter
Barkey, personal communication, 2016).
While the incidence of many rashes varies by countries and climates, the prevalence of one of the most
common types of rash, atopic dermatitis, is estimated to be up to 20% in school aged children. (Nutten,
2015). Atopic dermatitis is among the most common of all chronic childhood diseases (Laughter 2000), and it
has been described as having the greatest health-related quality of life impact of all chronic childhood
diseases (Mozaffari, 2007). Fourteen percent of children in Michigan are reported to suffer from skin allergies
with the highest rates among black non-Hispanic children (Villarroel, 2016). The prevalence of atopic
dermatitis and related conditions (e.g., eczematous dermatitis) is high in the adult population as well, and
this group makes up a significant percentage of office visits to dermatologists and primary care
providers. Recent estimates from the US Center for Health statistics indicates that 13% of adults in Michigan
have dermatitis, eczema or any other red, inflamed skin rash (Villarroel, 2016).
Some people have itching in their skin but have no visible rash. Sometimes this is attributed to dry skin,
especially if it is worse in winter and improves with use of moisturizers. The etiology of localized intermittent
itching with no visible rash is sometimes impossible to determine.

13

Almost all inflammatory skin conditions are exacerbated by stress, both physical (e.g., contact with irritating
chemicals) and psychological. For atopic dermatitis, psychologic stress is associated with both a gradual
worsening of existing rash as well as acute flares (Arndt, 2008). These effects are mediated through a
combination of biological and psychological stress factors, including changes in immune response and further
loss of skin-barrier function beyond that which is a hallmark feature of atopic dermatitis (Arndt, 2008).
Strategies to reduce stress and anxiety have been shown to be effective in reducing negative quality of life
impacts from atopic dermatitis (Arndt, 2008), and are an important part of effective comprehensive
management strategies (Tollefson, 2014).
Genetic and environmental factors have been shown to have a significant role in sensitivity and risk for
dermatitis. However, the interplay between genetic and environmental factors in dermatitis is complicated.
Atopic dermatitis, for example, has a well-known genetic predisposition, running in families often in
conjunction with asthma and hay fever. People with atopic dermatitis also have dry skin that is known to be
exacerbated by even minor exposure to irritants (especially soap and hot water). Atopic dermatitis is often
worse in the winter and is aggravated by mental, physical, and emotional stress. The rash in atopic
dermatitis is driven by itching, and the resultant scratching produces further damage to the skin barrier. This
leads to more exacerbation by irritants.
Another very common class of dermatitis is contact dermatitis, which is further divided into allergic contact
dermatitis and irritant contact dermatitis. External irritants can cause direct injury to the skin surface
through chemical effects or physical and mechanical effects resulting in irritant contact dermatitis. Common
causes of irritant contact dermatitis include chemicals (e.g., detergents, solvents, acids or alkaline solutions,
or prolonged hand exposure to wet work environments) and physical irritants (e.g., metal tools/instruments,
wood, fiberglass, plants such as poison ivy, and soil). Because repeated exposures over time can lead to
chronic eczematous dermatitis, a critical element in making the diagnosis of irritant contact dermatitis and
distinguishing it from atopic dermatitis, is a history of symptom onset within minutes to hours of exposure,
often with more pain or burning than itching (in contrast to atopic dermatitis) (Rietschel, 2004).
Allergic contact dermatitis is the result of a delayed hypersensitivity immune response to external agents that
a person is exposed to primarily through direct skin contact. Dermal sensitization involves a delayed allergic
response to a substance that is applied to the skin, which results in skin irritation such as redness and
swelling. Sensitization is also known to play a role in the onset or worsening of symptoms in some patients
with atopic dermatitis. Importantly, multiple exposures to an allergen are typically necessary for sensitization
to occur and symptoms of dermatitis to develop. Common allergens that can trigger such a response over
time include certain metals (e.g., nickel, cobalt, gold, and chromium), preservatives, cosmetics, fragrances,
hair care products, propylene glycol, antibiotic ointments, adhesives, and fabric dyes (Mowad, 2016).

Hair Loss

Hair loss has many possible causes that present in different but often very distinct patterns. Hair loss that
results in breakage of hair shafts often has extrinsic causes related to hair care techniques and external
exposures. Hair loss that results in loss of hair by the roots or hair loss that results in permanent scarring is
much less likely to be related to extrinsic factors and more likely to be related to internal factors (e.g., drugs,
thyroid disorders, internal disease like lupus). Too much ingestion of arsenic and thallium have been
14

reported to result in hair loss; however, lead and other metals have not been associated with hair loss even
in people with occupational exposures to high levels of lead and other metals.

Skin Conditions and Tap Water
Everything that comes into contact with skin, including water, can potentially be an irritant under the right
conditions, if applied for sufficient time and at a high enough concentration. Various chemical and physical
properties of water (e.g., pH, hardness, temperature) and some contaminants have been linked to skin
conditions (Tsai, 2013).
Tap water has been previously implicated as a cause of skin disease and irritation. However, studies of the
association between tap water quality and skin irritation are generally lacking. A recent review of possible
associations between skin irritation and tap water quality in the United Kingdom concluded that a lack of
data prevents any definitive conclusions (WRc Group, 2011). In their report, the WRc Group suggested the
need for studies evaluating the effect of different tap water parameters (e.g., water hardness, alkalinity, and
magnesium and calcium concentrations) on the physical and biological properties of human skin.
Additionally, research by the U.S. Environmental Protection Agency (EPA) on potential links between
chloramine (a chlorine based-disinfectant) and dermal, respiratory, and gastrointestinal irritation found no
evidence for causal link. EPA did create a Disinfectants and Disinfection Byproducts Rule to reduce exposure
to such products (EPA, 2016b) but this rule was not specific to potential for these particular health effects. A
study specifically examining the relationship between water hardness and eczema did not support switching
to soft water to improve eczema (Thomas, 2011). However, a recent British study found a link between
domestic water hardness, chlorine, and atopic dermatitis risk in over 1300 3-month-old infants (Perkin,
2016), consistent with findings from three previous ecological surveys (McNally, 1998; Miyake, 2004; ArnedoPenn, 2007). CDC/ATSDR has also conducted several rash investigations since 1954, the majority of which
were for rashes likely to be infectious in nature. A review of these investigations can be found in Appendix A.

Objectives of this Investigation
In response to continued rash reports from Flint community members and healthcare providers following the
switch back to DWSD water, on February 3, 2016, the Michigan Department of Health and Human Services
(MDHHS) launched an investigation into rash complaints from residents using the Flint municipal water
supply. The objectives of the rash investigation were to:
•

better understand and characterize rash cases,

•

explore causes of the rashes and possible associations with the current Flint water supply, and

•

make recommendations for public health interventions.

On February 25, 2016, MDHHS requested assistance from the Centers for Disease Control/Agency for Toxic
Substances and Disease Registries (CDC/ATSDR) to support this investigation. Through the Unified
Coordination Group, convened by federal and state government responders, the CDC/ATSDR Assessment of
Chemical Exposures (ACE) program and EPA agreed to assist.

15

The study design is consistent with a case series study, with a focus on case characterization. The
investigation did not include a control population without rashes and did not follow participants over time.
The primary questions explored by this investigation are:
• Is the water provided to Flint residents from DWSD as of October 16, 2015 associated with initiating
or worsening rashes?
• Is there evidence of rash medical history and historical water sampling (from the Flint Water
Treatment Plant) that implicates water from the Flint River in initiating or worsening rashes?
Because the study team did not have access to reliable information about individuals’ rashes over time, it
relied on patient questionnaires and assessments by dermatologists both to obtain a clinical rash history and
to characterize the rashes. The study team also evaluated historical data on water quality during the time
water was sourced from the Flint River, and water samples collected from residents of individuals with rash
complaints. Retrospective, home-based water samples from residences of individuals with rash-related
complaints prior to this investigation were not available. As a result, it was not feasible to conduct a
retrospective investigation of skin conditions that existed during the time the water was sourced from the
Flint River.

16

Section 2: Methods
Identification of Individuals with Current and/or Worsening Rashes
Individuals with rashes were identified between January 29 and May 11, 2016, using several methods:
• MDHHS issued three press releases, encouraging affected individuals to call an existing hotline to
access local resources. Rash callers were referred to MDHHS.
• MDHHS released health alerts to the medical community in Genesee and surrounding counties,
instructing them to refer patients with rashes to MDHHS (i.e., with patient consent).
• MDHHS and CDC/ATSDR personnel accompanying the Michigan Department of Environmental
Quality (MDEQ) and EPA staff on visits to homes identified people with rashes and reported their
contact information to MDHHS for follow up (i.e., if people agreed to participate in the study).
• The Genesee County Health Department forwarded names and contact information of anyone who
called with a rash, with consent from the person calling.
After participants were identified, an MDHHS epidemiologist or CDC/ATSDR team member called the
individuals with reported rashes to determine if they met the case definition. Cases were defined as
individuals with Flint municipal water exposure reporting a current or obviously worsening rash with onset on
or after October 16, 2015. A flow chart of the rash response protocol is provided in Appendix A.

Questionnaire
A questionnaire adapted from a prior assessment conducted by the ATSDR Assessment of Chemical Exposure
team related to potential health effects thought to be caused by chloramine-treated tap water in Vermont
(Appendix B) was used to assess the characteristics of the rashes and tap water use. At least four attempts
were made to contact all individuals meeting the case definition to administer the questionnaire.
Interviews were conducted by phone whenever possible. If an individual requested an in-person interview or
required a translator, the interview was performed in person. Parents or legal guardians were interviewed to
collect information for children under 18 years of age. With parental permission, one older teenage child was
interviewed directly.
All interviewees gave verbal consent before the questionnaire was administered. All participants were
instructed that their participation was strictly voluntary and that they could decline to answer any question
and could stop the interview at any point.
After the interview was conducted, participants were asked to participate in a free dermatology screening
with a local dermatologist. MDHHS or a member of the CDC/ATSDR team helped schedule these
appointments. If transportation was needed, the interviewer or MDHHS staff helped make these

17

arrangements through the Mass Transportation Authority. Participants were also asked if they wanted EPA to
test their water.
Survey data were managed in an Epi Info™ 7 v.7.1.5.2 database. Data were proofread to ensure accuracy in
data entry. Descriptive statistics were generated from clinical and questionnaire data using Epi Info™ 7 and
Excel 2013.

Collection and Analysis of Water Samples
Water samples from 170 homes of individuals who completed the rash questionnaire and agreed to
participate in the water quality testing were collected, labeled, preserved, stored and shipped to either the
EPA Certified Regional Laboratory (CRL) or a designated contract laboratory for analysis of a range of metals
and water-quality parameters. One of these homes were excluded from the analyses due to their reported
use of a private well and/or water treatment, thus 169 homes are represented in the analyses). The
collection and analysis of the water samples were performed in accordance with the EPA Drinking Water
Lead and Water Quality Sampling Quality Assurance Project Plan (QAPP)
(www.epa.gov/sites/production/files/2016-06/documents/epa_flint_qapp-revision_2.pdf). EPA sampling of
residential tap water was conducted between January and early May 2016, several months after the switch
back to the DWSD water supply (i.e., on October 16, 2015). Only the existing (current) source of water (from
DWSD) was available for testing in homes of Flint rash investigation participants. Samples collected from
residences with a rash complaint during the period that the Flint River served as the municipal water source
do not exist. However, limited historical water-quality data (based on sampling at the water treatment plant
when water was sourced from the Flint River) were reviewed.
Microbiological quality was not routinely assessed as part of this investigation. Samples for bacterial testing
would require more complicated sampling protocols, and there were no indications from the dermatologists’
assessments that bacterial or viral infectious causes were a likely cause of any of the rashes. Proper water
disinfection levels reduces the risk of growth and spread of these organisms. Thus, residual chlorine levels
were measured to ensure the levels were high enough to prevent microbial contamination, but not too high
as to cause irritation. When cold water chlorine levels were found to be below 0.05 ppm, a water sample
was sent to the Genesee County Health Department Laboratory for analysis of total coliforms and E. coli.
Cold water samples were collected at the kitchen sink faucet,
a bathroom sink faucet, bathtub faucet, and shower head
with one or more hot samples collected from the shower
head and/or bath tub. A range of elements and chemical
compounds, including those that are known to be skin
irritants or associated with hair loss, were measured (Table 4­
1).

Pilot Study to Evaluate Organic Compounds
During the course of the investigation, a pilot
study was initiated to evaluate the levels of
organic compounds that may be present in
residential water. The focus of the pilot study
of 11 homes was to evaluate the levels of
disinfection byproducts and many other
organic compounds in cold and hot water
samples taken where residents would shower
or bathe. See Appendix C for methodology
and results of the pilot project.

18

Contaminant levels from home-based water samples were compared to:
• federal drinking water standards or health advisories,
• levels measured at the Detroit Water Treatment Plant, the current water source for the City of Flint,
• levels detected in other water systems using chlorine for disinfection, and
• health-based screening values from ATSDR and EPA.
Additional analyses were conducted to examine the differences in hot and cold water taken from the shower
head. Statistical analysis of the data was performed using SAS® software.

Dermatological Assessment
Four board-certified dermatologists associated with the Genesee County Medical Society volunteered to
spend one half day per week screening investigation participants in their individual clinics. Dermatologists
were blinded to the water-quality data collected from the homes of study participants. The dermatologists
worked together to develop and implement the protocol for the dermatologic assessment. The objectives of
the dermatologic assessments were:
• identifying the clinical characteristics of rash and other dermatologic conditions in individuals with
rash complaints who were exposed to Flint municipal water,
• assessing the relationship between clinical presentation and exposure history,
• making a clinical diagnosis when appropriate, and
• providing recommendations to primary care providers of study participants regarding management
and follow up of those individuals being screened.
After the screening evaluations, a copy of the assessment with any recommendations for rash management
was sent to each participant and their primary care physician. The dermatologists obtained written informed
consent for the screening evaluations and release of information to primary care providers and MDHHS.
CDC/ATSDR team members abstracted clinical information from assessment forms and entered it into a
database. All results were coded to protect subject confidentiality. A copy of the assessment form is provided
in Appendix D.
Once the dermatologic examinations were completed, the lead dermatologist worked with study
investigators to classify all the diagnoses according to the likelihood that they could be related to exposure to
Flint water. The goal of the classification was to first divide all diagnoses into those that were “definitely not”
water related and those “possibly” related to the water based on known causes of diagnoses made and any
temporal relationship with Flint water exposure. Conditions for which there was uncertainty among health
care providers as to their cause were categorized as possibly water related. Conditions that were possibly
water related were further divided, based on whether they were a dermatitis or not and whether they had
resolved or not.

19

•

Category 1 – conditions and diagnoses that were definitely unrelated to the water

•

Category 2 – dermatitis diagnoses that were considered possibly related to water exposure

•

Category 3 – non-dermatitis diagnoses that were considered possibly related to water exposure

•

Category 4 – resolved or inactive rashes possibly related to water exposure

Active rash conditions possibly related to water exposure (i.e. categories 2 and 3) were assessed in terms of
clinical severity: mild, mild-moderate and severe based upon physical characteristics (i.e. redness, swelling,
skin thickening, excoriations from scratching), distribution (generalized versus localized), relative potency of
recommended treatments and reported frequency and intensity of symptoms and their impact on daily
living. See Appendix D for a complete list of diagnoses in each category.
Diagnoses were also categorized by whether or not they were eczematous dermatitis or not. This
determination included both active (most of Category 2) and resolved or inactive (some of Category 4)
diagnoses. Descriptive frequencies of the clinical data were generated using Excel 2013 and Epi Info 7 v.
7.1.5.2.

Data Analysis - Relationship between Water Quality and Rashes
The analysis focused on determining whether there were consistent patterns in the rash history and
categorization, and on correlating relevant rash characteristics to the water sampling data. Microsoft Excel
and SAS software was used to transfer, clean, and combine datasets containing rash categorization and
household water testing measurements. SAS was used as the primary tool to conduct the statistical analyses,
and Excel was used as the primary tool for conducting quality assurance of the results and ensuring
reproducibility. A detailed description of the statistical analyses used on this data can be found in Appendix E.

Ethics Review
The Michigan Department of Health and Human Services Institutional Board Review (IRB) for the Protection
of Human Subjects approved this investigation with non-research determination (MDHHS IRB Log #201602­
01-NR).

20

Section 3: Questionnaire Results
A flowchart showing the distribution off individuals involved in each part of the investigation is included in
Appendix B. A total of 614 individuals were referred to or contacted MDHHS from January 21, 2016 to April
29, 2016. Referral sources are displayed in Table 3-1. Figure 3-1 shows the distribution of referrals over the
15-week referral period. Of these 614 referrals, 429 (69.9%) met the case definition (new or worsening of
pre-existing or chronic rashes after the switch back to DWSD water on October 16, 2015), 104 (16.9%) did not
meet the case definition, 78 (12.7%) could not be reached, and 3 (0.5%) elected not to participate in the
investigation.

Table 3-1. Source of rash referrals
Referral Source

N

Public calls to 211
US EPA home visit/CDC-ATSDR consultation
MDHHS/MDEQ home visit
Doctors’ offices
Genesee County Health Department
MDHHS Division of Environmental Health’s MITOXIC hotline
Governor’s Constituency Services Office
TOTAL

291
155
81
33
26
22
6
614

%
47.4
25.2
13.2
5.4
4.2
3.6
1.0
100.0

Figure 3-1. Distribution of referrals by week (N=614)

21

Of the 429 individuals classified as cases, 390 (90.9%) were interviewed, 32 (7.5%) were unable to be reached
after four or more follow up calls, and 7 (1.6%) declined further participation. Data from the 390 interviewees
comprise this portion of the analysis.
Participants ranged in age from <1 to 93 years. The median age was 51 years, and the mean was 43 years.
The majority of the interviewed cases were female (254, 65.1%). Of the 296 adults over the age of 18 with
occupational data available, 83 (28.0%) reported working at the time of interview. Two participants under
the age of 18 were employed.
The frequencies of reported chronic diseases, skin conditions, and allergies are displayed in Table 3-2.
Frequencies of reported metal allergies are displayed in Table 3-3.

Table 3-2. (N=390)
Reported pre-existing medical conditions
Pre-existing Condition
N

Table 3-3. (N=390)
Reported metal allergies
%

158

40.5

75
54
48
37

19.2
13.8
12.3
9.5

Skin conditions
Eczema
Psoriasis
Other dermatitis

71
42
9
7

18.2
10.8
2.3
1.8

Allergies
Seasonal allergies
Food allergies
Metal allergies

110
70
36
15

28.2
17.9
9.2
3.8

94

24.1

Chronic diseases
Asthma
Diabetes
Other chronic lung disease
Heart disease

Current smoker

Metal
Nickel*
Metal, not specified*
Gold
Copper/brass

n
8
7
1
1

%
2.4
1.7
0.3
0.3

*Two reported allergy to nickel and other
metals.

Self-Reported Rash Characteristics
The questionnaire asked about the history of each participant’s rashes, including date of initial onset and
date(s) of any exacerbations. Questions elicited a comprehensive history of participants’ rash histories, both
current and prior. Of the rashes reported, 149 (38.2%) had onset dates October 2015 and later, 189 (48.5%)
had rashes with onset prior to October 15 that worsened after the switch back to DWSD water, and 52
(13.3%) of respondents did not provide an onset. For rashes that had onset dates after October 2015, over

22

half (57%, n=85) had onsets in January or February 2016. Data specific to rashes that existed before the
switch to Flint River water are not available.
Frequencies of rash symptoms are listed in Table 3-4.
At the time of interview, 348 (90.2%) of 386 participants that
provided a response to this question reported their rash was
still present, 35 (9.1%) said that it had resolved, and 3 (0.8%)
did not know if their rash had resolved. In addition, 175
(45.7%) respondents reported hair loss.
The most frequently reported aggravating factors were
contact with water/bathing/showering (193), nothing (50),
and any contact with the rash (e.g., by clothing, fingers) (30).

Reported Changes in Water Quality and Use
Over 77% of respondents (296/383) reported changes in
their tap water quality at the time their symptoms began.
Reported changes included: smelled bad (n=87); had a
bleach/chlorine/chemical odor (n=64); and smelled like
sewage (n=29), swamp or fish (n=11), or rotten eggs/sulfur
(n=10). Other commonly reported changes were in
appearance: brown (n=108) or yellow (n=32) color or being
cloudy/foggy (n=44). Individuals often reported multiple
water quality changes.
When asked if they noticed changes in the water pressure at
the time of symptom onset, 152/374 (40.6%) individuals
responded that they had. These included 123/152 (80.9%)
reporting a decrease in water pressure, 8 (5.3%) reporting an
increase in water pressure, and 11 (7.2%) reporting both an
increase and a decrease. Several individuals not reporting a
change in water pressure noted that the water pressure
fluctuated.
Participants were also asked whether they changed the
source of water they used for household activities including
that used for feeding pets. The results are presented in Table
3-5.
Other survey questions focused specifically on behavior
changes relative to bathing habits. Nearly 80% (296/371) of
respondents reported changing their bathing or showering

Table 3-4. Frequency of current rash
symptoms
Description

n

%*

Itchy skin

356

92.0

Raised bumps

266

69.6

Dry or flakey skin

257

69.1

Painful skin

191

50.7

Hives

134

36.0

Other**

239

*Number of responses varies from 372–387
**Includes redness, burning, bumps, blisters,
welts, and irritation

Table 3-5. Report changes in water source
for personal care and household activities
following onset of rash symptoms (N=390)
Activity
N
%
350
89.7
Drinking water*
Bottled water
Filtered water
Cooking*
Bottled water
Filtered water
Brushing teeth*
Bottled water
Filtered water
Washing dishes
Showering
Other
Pets/animals
Taking a bath
Doing laundry
Using a hot tub

311
9
299
246
20
250
216
11
80
53
43
14
37
18
9

76.7

64.1

20.5
13.6
11.0
9.5
4.6
2.3

*Alternative water source was collected
using an open text field; only the most
common sources are shown.

23

habits. Of these, 223 (75.3%) were showering less frequently, and 209 (70.6%) were taking shorter showers.
There were 185 individuals (49.9%) who reported changing their bathing method. These changes included
59/185 (31.9%) bathing with bottled water, 25 (13.5%) showering at a location that does not use Flint
municipal water, 20 (10.8%) taking sponge baths, 17 (9.2%) taking showers with cooler water, and 7 (3.8%)
using baby wipes.
The primary factors motivating changes in tap-water use included symptoms (184), health concerns (156),
and media reports (119). Twenty-two individuals indicated that they changed their tap water use primarily
based on a doctor’s advice.

Medical Care
Around two-thirds of the interviewees reported seeking medical care for their symptoms. Just over a third of
these individuals were aware of receiving a diagnosis, and two-thirds received treatment. Many individuals
(222/358, 62.0%) treated their rashes with over the counter products. The most commonly used products
listed were lotions (56), hydrocortisone cream (37), other creams (37), diphenhydramine (Benadryl) (33), and
oils (26).

Summary of Questionnaire Data
The interview results provide a better understanding of the characteristics of Flint residents who reported (or
were reported as having) rash concerns.
• Many individuals were unable to identify when the rashes started or worsened, limiting the ability to
draw inferences about the relationship of rash onset and the water switch. However, over half of
those who identified a date of symptom onset reported that it was prior to October 2015.
• Most of the respondents were adults (median age 51), and itchy skin was the most common skinrelated complaint.
• A majority of study participants reported other non-skin symptoms experienced along with their
rash. The most common of these included diarrhea and eye irritation. These collective symptoms
were the primary factor leading a majority of study participants to change their routine bathing or
showering practices (e.g., decreasing the frequency and/or duration of showers, avoiding Flint
municipal water for bathing purposes by using bottled water or using facilities supplied by an
alternate source of water).
• Few study participants reported using filtered water for any purpose. Changes in color, odor, and
reduced water pressure were among the subjective water quality changes noted by study
participants.
It is clear from the interview data that a number of survey participants experienced rashes and other irritant
effects thought to be associated with water. The data also demonstrate significant behavioral changes
associated with bathing and showering due to health concerns associated with perceived water quality.
There was no consistent pattern associated with timing of rashes, however our ability to draw specific
conclusions was limited based upon the fact that many participants were unable to identify a specific time
when their rashes started or worsened.
24

Section 4: Water Testing Results
Metals
Table 4-1 presents data on levels of several metals (i.e., arsenic, chromium, copper, nickel, and silver) and
water quality indicators (i.e., chlorine, pH, and hardness) that could be reactive with the skin. The table also
compares levels of contaminants found in household water with those found at the Detroit Water plant,
which is the source of the water before it travels through Flint pipes. The table shows the water composition
of the household samples and the Detroit water to be comparable, and provides a comparison to regulatory
standards and health based guidance levels for reference. It is noteworthy that the types of metals and
minerals detected in the residential water are generally found in any water systems that use surface water as
a drinking water source. The results are also generally similar to the analysis reported in the annual water
quality reports for finished water from the City of Detroit water system, which uses Lake Huron as its source
water and is the current water supplier to the City of Flint (DWSD, 2016).
The levels of metals and minerals are also generally similar to those reported in water for the City of Chicago,
a large, older urban municipality that draws source water from Lake Michigan. However, some homes in Flint
have higher levels of several metals (cadmium, copper, iron, lead, manganese, and zinc) than water from
Detroit or Chicago. The sources of these elevated metals are likely to be related to releases from water
service lines, internal plumbing, and fixtures resulting from inadequate corrosion control during the period of
the use of the Flint River as a water source (see Appendix C for a detailed description of the statistical
analysis of metals data and water quality measurements for the analysis of residential water of individuals
who participated in the rash investigation). Comparisons in this report are restricted to the current municipal
water supply for Flint residents (i.e., the DWSD/Lake Huron supply). Sampling data for residential tap water
during the period of time that the Flint River served as the drinking water source is limited to testing for lead
and copper levels and did not include testing at homes for other metals or water-quality indicators.
Of those metals that can be reactive with skin, arsenic, chromium, and silver do not exceed the EPA drinking
water standards. The other metals exceed their standard/regulatory guidance levels with a relatively low
frequency: copper (0.9%) and nickel (0.1%). Further, although there were higher levels of some metals in the
water of some residences, there were not generally high levels across all homes with reported rashes. It is
likely that these exceedances are related to specific conditions in individual homes related to the impacts of
the previous corrosive condition of the water in pipes and fixtures.

Other Water Characteristics
Other water characteristics known to have potential association with skin irritation or rashes are chlorine,
water hardness, and pH. Residual chlorine levels were measured from water in all homes sampled as a part
of this investigation. The World Health Organization (WHO) recommends a minimum concentration of 0.2
mg/L, but not to exceed 5.0 mg/L. When residual chlorine levels were below 0.05 mg/L, EPA collected
samples for bacterial testing for total coliform and E.coli. Only 1 of the coliform tests was positive, which led
to a request for the City of Flint to flush the water main to raise the chlorine level in the incoming water. The
average chlorine level in homes tested for rash complaints was 0.60 mg/L, with a maximum detection of 2.2
25

mg/L, indicating that the levels were protective of microbial contamination, but not above levels that would
cause irritation. The levels are also similar to those in the Detroit water system found in Table 4-1 (see
Appendix C for a summary of the results for the inorganic and water quality indicators).
Water hardness is measured by the amount of calcium carbonate in the water. High water hardness has
been known to be associated with skin irritation. While there is a range in hardness, the distribution of water
hardness values was generally very close to the average of 100 mg/L of calcium carbonate, which is
considered to be moderately hard water. The level is essentially the same as the level of hardness in the
finished drinking water in Detroit (average hardness=105 mg/L). With regard to pH, levels ranged from 6.0 to
8.3. Only one home whose water pH was outside the secondary drinking water standard range, and only five
readings were above the range found in for Detroit water (see Table 4-1).
Certain metals (see Table 4-1) have been associated with either allergic or irritant dermatitis. All arsenic, total
chromium, and silver concentrations were below the lowest drinking water regulations. Small percentages of
the copper (0.9%) and nickel (0.1%) concentrations exceeded the lowest drinking water regulations. Not all
drinking water regulations are health-based, metals levels were also compared to health-based drinking
water levels. Health-based drinking water levels are not typically set based on dermal effects. However, they
are expected to be protective of skin exposure as those levels are designed to be protective of the most
sensitive health effects. There are no health-based levels based on dermal irritation or allergenic potential.
No nickel and silver water concentrations exceeded the health-based drinking water level shown in Table 4.1.
Maximum concentrations for arsenic and copper were above the health-based drinking water levels, but the
average concentrations were below. A total chromium (trivalent and hexavalent chromium) Maximum
Contaminant Level Goal (MCLG) is available and all samples were below that level. The MCLG is the level of a
chemical in drinking water below which there is no known or expected risk to health (non-enforceable public
health goal).

26

Table 4-1. Summary of Detection Levels of Elements and Chemical Compounds that have been Associated
with Rashes or Other Skin Problems
% Above
Regulations/
Comparison
Values

Concentration
(µg/L; except
as noted)

Drinking Water
Regulations

Arsenic

7.1- max
0.7- average

10
(MCL)1

None

Not detected
(less than 2)2

6 (RSL-child,nc)3

Chromium,
total

5.2- max
0.4- average

100
(MCL)

None

0.28 (average)4

44
(RSL-nc)

Copper

4,800- max
86- average

1,000 (SMCL)3
1,300
(Action Level)4

1.0 (average)4

1,300 5

Nickel

110- max
4.1- average

100
(HA lifetime)6

0.1%

Not detected
(less than 10)2

390 (RSL-nc)3

10- max
0.2- average
2.2 mg/L (max)
0.6 mg/L
(average)
115 mg/L (max)
97.8 mg/L
(average)

100
(SMCL)7

None

Not reported

94 (RSL-nc)3

4.0 mg/L
(MRDL)8

None

0.56 to 0.97 mg/L,
(range)4

4.0 mg/L (MRDLG9)

No regulatory
limit10

None

88 to 130 mg CaCO3/L
(range), 106 mg
CaCO3/L (average)4

No health-based level

7.01 to 7.65 (range);
7.37 (average)4

No health-based level

Contaminant

Silver
Chlorine

Hardness

6 to 8.32
Average: 7.21

pH

(µg/L)

6.5 to 8.5
(SMCL)5

0.9%

1% (below
regs)

Concentration at
Detroit Water Plant
(µg/L)

Health-based level for
drinking water (µg/L)

Table 4-1 Footnotes
1 MCL
2

– US EPA Maximum Contaminant Level (the highest level of a chemical that is allowed in drinking water)

Detroit Water and Sewerage Department, water testing results, June 2008

3 RSL

– U.S. EPA Risk-based Screening Level for tapwater exposure – this is a health-based level calculated to make sure people are not exposed to too
much of this chemical from drinking water, skin contact, or breathing in the chemical

4 Detroit

Water and Sewerage Department, Water Quality Report, 2015

5 Action

Level for Lead/Copper Rule – US EPA Lead and Copper Rule (the action levels for the 90th percentile of compliance samples is based on
technical feasibility of reducing lead and copper in drinking water through optimizing corrosion control)

6 HA

– US EPA health advisory level for drinking water (this is a health-based level set to make sure that people are not exposed to too much of this
chemical in their drinking water over a lifetime)

7 SMCL

– US EPA Secondary Maximum Contaminant Level (non-mandatory water quality standards established only as guidelines for aesthetic
considerations, such as taste, color, and odor. These contaminants are not considered to present a risk to human health at the SMCL.)

8 MRDL

– US EPA Maximum Residual Disinfectant Level (the highest level of a disinfectant allowed in drinking water)
MRDLG – US EPA Maximum Residual Disinfectant Level Goal - the level of a drinking water disinfectant below which there is no known or expected
risk to health (does not include the consideration of the disinfection benefit of the chemical)
9

10 Hardness

definition: soft water 0-60 mg/L; moderately hard water 61-120 mg/L; hard water 121-180 mg/L; very hard water > 180 mg/L

27

Disinfection Byproducts Sub-Study
This study found the disinfection byproduct (DBP) levels are below regulatory limits and below health-based
screening levels (results of the organic chemical testing are presented in Appendix C). Hot and cold water
samples from six homes where residents also complained of rash were tested. Five homes, where there was
a request to EPA for water sampling but where there were no concerns about rashes among the residents,
were selected as comparison homes. Water was tested for DBPs, including trihalomethanes (THMs),
haloacetic acids (HAAs), and haloacetonitriles; volatile organic compounds; and semi-volatile compounds.
Results for homes where residents reported rashes were compared to the comparison homes, to regulatory
values for total THMs and HAAs, and to levels for these compounds that have been reported in the scientific
literature. The results indicate that all of the values for the rash homes and the comparison homes are below
EPA federal drinking water standards, WHO guidelines, and national statistics for DBPs. In addition, all of the
results indicate that the levels of organic chemicals found in the residential water samples are within
expected ranges that have been reported for chlorinated water systems.
Acetone was the only other organic compound that was detected. It was found in several homes where
residents reported rash (max = 170 µg/L; average = 34 µg/L) and the comparison homes (max = 16 µg/L;
average = 8.6 µg/L). The apparent difference in the acetone concentration between the rash and comparison
group was the result of one home, where the acetone concentration was elevated for both hot and cold
water. However, even the acetone level for that particular home was well below the level of health concern
for ingestion of water (ATSDR screening level of 9,000 µg/L) and not likely to have effects on the skin.

Aesthetic Water Quality
In addition to the comparison to the primary drinking water standards and health-based criteria, it is also
important to consider the aesthetic characteristics of the water (e.g., taste, odor, coloration, particles). EPA
does have secondary, non-enforceable standards that are inclusive of those aesthetic effects. Appendix C
shows a summary of the exceedances of regulatory criteria. The aesthetic secondary standards were
exceeded for aluminum (44.5%), iron (11.9%), and manganese (4.3%). Residences where those exceedances
occurred could have experienced an adverse effect on the taste, odor, and coloration of the water.
Substances that cause changes to water (e.g., color, odor, taste) are not usually harmful to human health;
however, these changes are important drivers of decision-making about sources of water to use and suitable
uses for water (WHO, 2011).

Historic Conditions: Flint River Water (April 2014–October 2015)
To evaluate changes in water quality at the time of the switch to the Flint River as the water source, reports
from the Flint water treatment plant to the MDEQ were reviewed. These data were evaluated given the lack
of residence-specific historic water sampling data at the time of the investigation. The available information
is limited to a few water quality parameters, and reflects only the measurements taken at the water
28

treatment plant as water left the treatment plant and entered the distribution system. However, the profile
of changes for pH, water hardness, and chlorine levels in the water leaving the plant demonstrates the
instability in those parameters throughout the 18-month period (April 2014 to October 2015) in which the
Flint River served as source water treated at the Flint water treatment plant and are likely to reflect
variability in these levels at resident’s homes (see Appendix C). Key examples are provided below:
•

Water Hardness
During the year prior to the Flint River switch (January 2013 to March 2014), the water hardness was
consistently at 98 mg CaCO3/L. However, during the period of April 2014 to October 2015, when Flint
River water was being treated and distributed through the Flint water system, the average water
hardness increased significantly to 173 mg CaCO3 /L, with monthly spikes over 250 mg CaCO3 /L. After
the switch back to the City of Detroit water source in mid-October 2015, the water quality parameters
returned to those measured prior to April 2014. Although there are no federal drinking water
standards for water hardness, levels above 180 mg CaCO3 /L are considered to be an indicator of very
hard water. Hard water is associated with skin dryness and irritation (McNally, 1998; Miyake, 2004;
Perkin, 2016).

•

pH
While Flint was using DWSD water (prior to April 2014 and after October 2015), pH level was
consistently around 7.3. During the period of using Flint River water (April 2014 to mid-October 2015),
pH increased significantly to an average of 7.7, with monthly spikes of pH over 8.5. Alkalinity is
associated with skin dryness and irritation (WRc, Group 2011).

•

Chlorine
While Flint was using DWSD water (prior to April 2014 and after October 2015), the chlorine level of
water leaving the Flint treatment plant had a consistent average free chlorine level of 0.9 mg/L.
During the period of using Flint River water (April 2014 to mid-October 2015), the chlorine levels were
irregular, with an average level of 2.0 mg/L. For several months during the summer and fall of 2014,
the chlorine level exceeded 3.0 mg/L, which may have contributed to elevated levels of disinfection
byproducts in the Flint water system observed during that time. Elevated chlorine levels are
associated with skin dryness and irritation (Perkin, 2016).

It should be noted that these water quality measurements were taken at the plant as water entered the
water distribution system. Measurements are not required to be taken at residences, so we cannot be certain
that the measurements at the water distribution system and the conditions at individuals’ residences were
the same.

Summary of Water Sampling Data
Some exceedances of regulatory levels for some metals—including metals that have been known to be
associated with skin irritation as a result of direct contact—were observed in a small number of Flint homes.
However, there does not appear to be a general pattern of metals detections in homes where people with

29

rashes reside that would identify specific causative factors for the rashes. Some of the detected metals and
minerals can cause the water to be yellow, brown, or taste metallic, even at low levels.
Other current water quality indicators, such as the level of acidity (as reflected in pH values) and water
hardness, are consistently at a moderate level and similar to that for drinking water in Detroit. Therefore, it
does not appear that these indicators are likely contributors to skin rashes at the present time.
Levels of organic chemicals found in the residential water samples are within expected ranges that have been
reported for chlorinated water systems. A comparison between homes where individuals with complaints of
rash resided in the pilot study showed no significant differences in the levels of DBPs in Flint homes where
there were no complaints of rashes. It is unlikely that these chemicals contributed to the development of
rashes.
However, it is clear from the historical water quality data that during the period of time when the City of Flint
used Flint River water as its source, several water quality indicators were very unstable, and differ from
Detroit water. Those indicators include significant increases in water hardness, pH, and chlorine, all of which
have previously been associated with skin irritation and dryness. The water quality change during that time
may have contributed to the onset or worsening of irritant effects among individuals using the water.

30

Section 5: Dermatologic Assessments

Demographics of the 122 participants who met the case
definition and received dermatologic exams are displayed in
Table 5-1. A comparison of the demographics of those who
participated in the dermatologic screenings to the larger
group of those who participated in the case interviews can be
found in Appendix D. These groups were similar when
compared according to mean and median age, sex,
employment status, history of prior skin conditions, history of
metal allergies, and reported hair loss. The two groups
cannot be compared by race and ethnicity as these data were
only gathered during the dermatologic assessments.
The demographics of the City of Flint as of the 2010 US
Census are provided in Appendix D. Individuals who received
dermatologic screening are fairly similar to the larger
population of Flint.

Table 5-1. (N=122)

Dermatology patient demographics

N
%
Age
<5
5-17
18-64
65+

9
11
80
22

7.4
9.0
65.6
18.0

Sex
Female
Male

71
51

58.2
41.8

Race
Black
White
Mixed race

70
51
1

57.4
41.8
0.8

Among the 122 patients screened, there were fewer
individuals in the 5-17 age range and more in the 65+ age
range in the patient population than the City of Flint
Ethnicity*
population. The proportion of patients with black race
35
97.2
Non-Hispanic
(57.4%) is similar to the population of the City of Flint. The
Hispanic
1
2.8
broad distribution of age allowed for the characterization of
skin conditions that may vary in their expression by age.
*Only 36 individuals provided ethnicity
There was a higher proportion of patients with female sex
information.
(58.1%) compared with males; however, this does not
necessarily reflect any known differences in skin-condition
expression by gender. The most common diagnosis was eczematous dermatitis for which there is a female
predominance during reproductive years (Osman, 2007); however, the self-selective nature of case
ascertainment limits determining whether or not such a variable impacted the gender distribution of the
study population.
Clinical categories are listed in Table 5-2. Of the 122 patients, 24 (19.7%) were in Category 1, which was
unrelated to water exposure. The remainder were classified as being possibly water related (Categories 2-4),
with the majority in Category 2 (dermatitis possibly related to water exposure). Dermatologists were unable
to definitively state that any skin condition was causally associated with the water. The specific diagnoses
and racial distribution in each category are provided in Appendix D.

31

Table 5-2. Dermatologist diagnoses classification scheme
Clinical Category*
1) Diagnoses definitely unrelated to Flint municipal water exposure

% (N)
19.8% (24)

2) Dermatitis possibly related to water exposure

43.8% (53)

3) Non-dermatitis skin conditions possibly related with water exposure

22.3% (27)

4) Resolved/inactive rash possibly related with water exposure

14.0% (17)

*One individual had no skin condition based on clinical assessment.

Fifty-four (44.3%) patients were diagnosed with current or inactive eczematous dermatitis. Of 80 diagnosed
conditions deemed possibly related to water exposure, 51 (63.8%) were mild, 18 (22.5%) were mildmoderate, and 11 (13.8%) were severe. Prescription medications were recommended for 83/117 (70.9%)
patients. More detailed information is provided in Appendix D.
Month or year of symptom onset was available for 89% of clinically-screened participants. There was a higher
proportion of participants given a diagnosis definitely unrelated to water in the period after October 2015
compared with before (26.5% and 18.9%, respectively). The overall proportion of participants who were
identified as having either active dermatitis or non-dermatitis diagnoses possibly related to Flint municipal
water exposure was higher among those with symptom onset preceding October 2015. The proportion of
patients with clinically severe presentations was higher among those with onset prior to October 2015
compared with after October 2015 (15.4% and 5.6%, respectively). More detailed information is provided in
Appendix D.
Several patients reported histories of symptom onset or worsening within minutes to hours after showering
with Flint municipal water, followed by a lack of similar response when they began showering at locations not
serviced by Flint municipal water. Respondents reported that any re-exposure to Flint municipal water
through showering would elicit similar dermatologic reactions (often generalized itching with or without an
erythematous rash with small papules).
Hair loss or alopecia was assessed by the dermatologists. While hair loss was reported by a significant
proportion of study participants when interviewed (43.6%), only 14 of 122 (11.5%) reported hair loss during
their clinical evaluations. Of these, 9 (7.3% of patients screened) were found to have objective signs of hair
loss (e.g., breakage, clear thinning, patches of baldness) on examination. Half of the diagnoses (7 out of 14)
made by dermatologists regarding hair loss were deemed to be definitely unrelated to contact with the Flint
water. Many of the cases of hair loss which were classified as “possibly related” have no known cause (i.e.
central centrifugal cicatricial alopecia-two cases) or are autoimmune in nature (i.e. alopecia areata-two
cases). These disorders are not known to be related to any topical or systemic environmental exposure but
since participants noted they seemed to improve when Flint water was stopped they were deemed “possibly
related”. Two possibly related cases had mild telogen effluvium which is a temporary shedding known to be
stress related and one other case was a child with eczema that had prominent scalp involvement.

32

Summary of Dermatologic Assessments
All four dermatologists observed a high level of general concern about the water from all the participants in
the study. However, they concluded that the spectrum and severity of rashes among study participants was
similar to that seen in their daily practices for the same time of year.
Findings suggest that diagnoses made after October 2015 were more likely acute and of limited duration, and
less likely to be clinically severe, compared with chronic diagnoses, such as eczema, that were more likely to
have manifested prior to the transition in water source. This is because:
• A higher proportion of participants were given a diagnosis definitely unrelated to Flint municipal
water after October 2015 compared with before.
• The overall proportion of participants identified as having either active dermatitis or nondermatitis diagnoses possibly related to exposure to Flint municipal water was higher for those
with symptom onset before October 2015.
• The proportion of patients with clinically severe presentation (i.e. more significant skin
conditions) was higher among those with onset before 2015.
Rash conditions have many etiologies, and while many of the observed rashes are possibly water-related,
none of the clinical presentations resulted in a definite linkage to current water as the causative agent. It is
important to note, however, that symptomology and residence-specific water-quality parameters when the
Flint River water was in use are not available. This limits our ability to draw firm conclusions about the
relationship between Flint River water and rashes.
The timing of symptom onset or worsening within minutes to hours of showering reported by patients versus
the lack of similar response of showering in locations away from Flint is suggestive of a relationship between
showering and the reported skin conditions. This close temporal relationship was identified among
participants with rash onsets both before and after the transition back to water from DWSD. However, the
intermittent nature of patients’ symptoms made clinical assessment challenging, as there was often a lack of
physical findings when patients were examined by dermatologists. Importantly, no presumptive or confirmed
bacterial or viral infectious etiologies for rash were identified among the 122 patients screened.
Almost half of the diagnoses were some form of eczematous dermatitis. It should be noted that while the
underlying causes of skin irritation may differ, the resulting rashes may look quite similar. Rash occurrences
coincide with the cold and dry air during winter known to cause or exacerbate eczematous dermatitis in
some individuals. Some individuals in the investigation reported changing their behavior in a manner that
could make the rashes worse. Cessation of bathing altogether may contribute to some skin conditions, such
as seborrheic dermatitis and folliculitis. Others reported applying rubbing alcohol or using or alcohol-based
hand sanitizer directly on rashes, which can lead to further loss of moisture from the skin and increase the
risk of skin irritation and itching.

33

These results are not generalizable to the population of Flint because most study participants were selfselected. Further, even though over half of participants who were interviewed were scheduled for
evaluations, 38.9% of those scheduled did not present for their appointment, introducing an additional
element of self-selection. Thus the results should be interpreted with caution and in keeping with study
objectives.
Additional clinical follow up would help provide important information regarding the impact of treatment
recommendations provided to patients’ primary care providers. Additional information about resuming use
of Flint municipal water for showering and bathing without further development of rash and other skin
conditions would allow for a more complete understanding of the role of water and adequacy of clinical
treatments. However, it should be acknowledged that decision-making regarding when and with what
frequency to resume use of Flint municipal water is complex and involves individual assessments of water
quality (including taste, odor, and color). Equally important will be the community’s confidence in those
charged with ensuring a high level of water quality in public water systems, as well as their own history of
health.

34

Section 6: Relationship between Water Quality and Rashes
Both water sampling data and clinical assessments were available for 84 individuals. Because this
investigation did not include a comparison group of unaffected individuals, we compared water for
households in which residents’ rashes were categorized as “possibly water-related” (categories 2-4) to that
for residents whose rashes were deemed “unrelated to water” (category 1).
Descriptive statistics of metal and water quality levels for those parameters predetermined to be possibly
related to rash conditions by clinical category and for hot and cold water are presented in Appendix C.
Statistical analyses suggest that the overall water quality is similar across all rash categories. See Appendix E
for a summary of statistical comparisons across groups.
The metals and other water characteristics that were chosen for this component of the analysis were those
for which evidence exists in the scientific literature of an association with adverse skin effects: arsenic,
chromium, copper, water hardness, nickel, silver, thallium, zinc, pH, and chlorine (WRc, 2011). The selection
is based on evidence of either direct irritation (e.g., hardness, copper, arsenic, chlorine, pH), sensitization
(e.g., nickel, chromium), or dermal effects resulting from ingestion (e.g., arsenic, thallium).
None of the levels of these metals were considered by participating dermatologists to be sufficiently high
enough to be clinically significant or to cause rashes. For example, in the cold water samples, nickel levels
were about 3 times higher in the ‘possibly water-related’ rash categories compared to the ‘definitely not
water-related’ categories. However, levels in either case are well below the levels thought to elicit skin
sensitization and reaction. In addition, it should be noted that hot water sampling did not indicate a
difference between nickel levels across rash categories.
Nickel was included in the investigation because of its known sensitivity for some people. A large study of
approximately 75,000 individuals found that 15.5% developed contact dermatitis in response to a patch test
with nickel sulfate (5% in petroleum) (Uter, 2003). Studies of individuals that are known to be sensitive to
nickel respond to much lower concentrations (0.03-0.1%), but no effect is reported at 0.01% (reviewed in
ATSDR, 2006). Even the highest level of nickel found in current Flint municipal water is well below those
found to induce dermatitis and 99.8% of samples were also below regulatory drinking water limits.
Other metals noted have a statistically significant elevation in the possibly water-related categories, including
iron in hot and cold water samples, compared with water samples taken from homes of those with definitely
not water-related rashes. While iron is not known to produce rashes or exacerbate skin conditions, it is
associated with water discoloration, which was commonly reported in the questionnaire response.
Current water quality parameters such as hardness and chlorine were all at similar levels across the rash
categories and as previously indicated are in within expected ranges.
As mentioned, data on symptomology and water-quality parameters at important intervals (i.e., pre waterswitch period, water switch period, and post water-switch period) are not available, nor do we have water

35

quality data in from homes without rash complaints, limiting our ability to definitively associate water and
rashes.

Analysis of Water Quality and Rash Evaluation Conclusions
We were not able to identify any current water quality parameters that might be causing or exacerbating
rashes based on differences in current water quality and rash categories. These findings are consistent with
the general assessment of water quality discussed previously (in Section 4, Summary of Water Sampling) that
concluded there was no pattern of water contaminants or in exceedances of water-quality parameters that
characterized the homes sampled for this investigation.
The lack of a common implicating exposure should be interpreted with caution, given the limitations of these
data and the fact that samples were all taken at a single time from each household. Water quality and
concentration of metals are subject to variability over time. It is possible a substance was present in the
water at the time the participant’s rash began but was no longer in the water at the time of testing. It is also
possible that components of water quality before the switch from the Flint River back to the DWSD could
account for some of the rashes seen in Flint residents. Unfortunately, residence-specific data on water
composition and quality related to the actual timing of rash/skin irritation are not available, thus conclusions
also take into account a review of historic water-quality parameters. As previously indicated, the literature
on the relationship between water quality and skin conditions is limited. Although unlikely, it is possible that
an unknown and unmeasured water-quality parameter or combination of parameters may be present that
are or were affecting skin conditions in Flint. It is also possible that conditions during the time that the Flint
River was used as the water source contributed to skin conditions. It is not possible, based on the
information collected in this investigation, to assess the interaction between water quality and community
stress on skin conditions.

36

Section 7: Discussion, Recommendations and Next Steps
This report summarizes and presents findings of the investigation of rash and hair loss complaints possibly
associated with the Flint municipal water supply, whose source is currently Lake Huron. The investigation
sought to evaluate a wide variety of contaminants (including those identified as the most likely to be linked
with skin irritation or rashes) from residential samples collected from the most common sites of water usage
and at different temperatures. No presumptive or confirmed bacterial or viral infectious etiologies for rash
were identified among the 122 patients screened. It was not possible to provide an analysis of rashes in
relation to water quality during the time that the Flint municipal water supply was sourced from the Flint
River due to the lack of residence-specific water sampling data.
Although it is not something objective that can be easily quantified, one of the most significant observations
in this entire investigation has been the general level of anxiety and actual fear that virtually all participants
had about the safety of the water they were getting out of their tap. The questionnaire documented that a
very high percentage of people changed their bathing/showering habits because of these concerns. This
concern was heightened by the fact that people were previously told that their water was safe at a time
when it smelled and looked abnormal and that they were receiving mixed messages from outside groups and
various municipal authorities. For example boil-water advisories were issued, but municipal authorities also
told people that boiling water did not eliminate lead. Although not part of the official dermatology
assessment, all four participating dermatologists were quite struck by the level of anxiety and mistrust of
participants, the majority of whom had completely stopped using the water to bathe and/or shower because
of concern about the possible association of water exposure and their skin condition.
There was no specific contaminant, nor group of contaminants, in current water samples taken that suggest a
primary causal factor associated with the occurrence of reported skin conditions or hair loss. Evaluating skin
impacts related to exposure to metals in water is challenging because of limited information about the actual
dermal dose associated with skin effects. Even with metals such as nickel and chromium, exposures reported
in the literature as causing skin reactions are not directly comparable to exposures as a result of bathing,
showering, and handwashing.
It is important to note, however, that during the period of time when the municipal water was sourced from
the Flint River and when corrosion control was inadequate, and for a period of time following that, some
levels of metals were likely higher. In addition, differences in other water-quality parameters such as
hardness, chlorine and pH, supported by a review of historic data from the Flint water treatment plant,
indicate that water quality parameters known to be associated with some skin conditions (hardness, pH and
chlorine levels) were elevated. This is particularly relevant since a majority of the rashes reported in this
study began prior to the switch back the Detroit water system.
Findings suggest that diagnoses made after October 2015 were more likely acute and of limited duration, and
less likely to be clinically severe, compared with chronic diagnoses such as eczema, that were more likely to
have manifested prior to the transition in water source.
37

In sum, while we were unable to find a consistent pattern relative to the rashes and current water quality,
our findings were limited by the lack of historical data. Given the data on water quality during the time that
water was sourced from the Flint River, one plausible hypothesis is that conditions present during that time
could have triggered skin irritation, dryness and rashes, notably in susceptible individuals. Further, these
conditions could have been exacerbated by a variety of factors, including seasonal household conditions (e.g.
the heat being on with windows closed in the winter), self-care practices (e.g. use of some lotions and
creams), and fear and anxiety associated with the water crisis overall. Unfortunately, the lack of historical
data on either rash patterns in the community or residence specific water samples from that time period
make drawing more definitive conclusions impossible.

Limitations
This investigation has several limitations:
1. The water samples for this rash investigation were collected from January 29 through early May 2016.
The results of the water testing only reflect the conditions of the water in sampled homes at that time.
Therefore, the actual water conditions corresponding to the time when rashes or hair loss began or
became worse cannot be known.
2. There were no home-based water samples from residences with rash-related complaints prior to this
investigation. As a result, it was not feasible to conduct a retrospective investigation of skin conditions
that existed during the time the water was sourced from the Flint River.
3. Most rashes were self-reported. Only 25 participants were referred through a doctor’s office. Thus, the
study relied on a convenience sample, rather than a sample representative of the entire population of
Flint. Therefore, results from this investigation are not generalizable to the entire population in Flint.
4. Not all participants agreed to a dermatology appointment, which limited confirmatory diagnoses. In
addition, nearly 40% of participants were unable to keep scheduled appointments, which limited
comparison data. Further selection bias might have been introduced as a result of this high proportion of
scheduled appointments unable to be met.
5. About 13% of respondents could not provide any onset time period of rash/irritant symptoms and the
majority of onset times provided were not specific.
6. The etiology of rashes, in general, involves the interaction of multiple factors, including host factors,
genetic factors, and environmental factors that vary from person to person and between households.
We were unable to assess the independent contribution of such factors to rashes.
7. Participation in the investigation was voluntary and is not generalizable to the larger Flint population. A
comparison population from a similar sized city that did not experience corrosion of municipal water
plumbing infrastructure was not available to establish a baseline of information on occurrence of rash.
38

Recommendations
Certain types of dermatitis can be difficult to resolve. However, most rashes are readily treatable. Residents
who have persistent rashes are urged to seek medical care, either from their primary care provider or from a
dermatologist. Fortunately, almost all Flint residents are covered by, or have access to, health insurance. In
addition, there are two federally qualified health centers that can provide care to all Flint residents,
regardless of background or ability to pay for care. Medicaid eligibility has been expanded, and additional
resources have been made available to the federally qualified health centers to ensure that all Flint residents
have access to care, including for investigation of rashes. Behavioral health services are also available for
residents with symptoms related to stress and anxiety, which, as noted in this report, are quite common.
In light of the results of this investigation, the following recommendations are provided for individuals:
1. If you have a rash or are concerned that you may have a metal allergy, schedule an appointment with
your primary care provider for evaluation, treatment, or referral to a specialists such as a dermatologist
or allergist.
2. Take care of your skin, particularly if it is sensitive. Follow the tips from local dermatologists:
http://www.michigan.gov/documents/flintwater/Dos_and_Donts_of_Rashes_Dr_Barkey_Final_530621_
7.pdf
3. If water in your home is discolored or has an unusual odor, flush water until the discoloration disappears.
If you want your water tested, contact the City of Flint or the MDEQ.
4. Flint residents are encouraged to discuss any adaptive strategies with their healthcare providers, , such
as changes in showering frequency or source of water, changes in showering products, and general skin
care changes.

Next Steps
1. MDHHS will conduct follow up interviews of study participants who received dermatologic screening
assessments to determine whether participants received treatments recommended by dermatologists,
the status of rash complaints, and the effect of re-exposure to municipal water following resolution of
rash.
2. MDHHS will work with the Genesee County Medical Society volunteer dermatologists to provide
guidance to primary care physicians on diagnosis and effective management strategies for the types of
rashes most commonly diagnosed among study participants. This will build upon general guidance on the
role of primary care physicians in the treatment of eczema that was provided by the dermatologists to
the primary care physicians of study participants who were diagnosed with eczematous dermatitis.
MDHHS and the dermatologists will continue working with the Genesee County Medical Society and

39

expanding outreach to include the Greater Flint Health Coalition and the Genesee County Osteopathic
Society.
3. Complete results of this investigation will be posted by MDHHS online at
http://www.michigan.gov/flintwater. It will also be posted online by the Agency for Toxic Substances
and Disease Registry.
4. MDHHS will continue ongoing surveillance of rash and other related health complaints in Flint by
monitoring trends in patient-reported data from Genesee County emergency departments via the
Michigan Syndromic Surveillance System (MSSS). Further review of Flint municipal water data from
periods before, during, and after the Flint River served as the municipal water source, in comparison to
data from MSSS and the Michigan Medicaid program will help provide further insight into potential
water quality changes temporally associated with rash.
5. EPA will continue to monitor the status of the Flint Water system.
6. The Department of Health and Human Services, including CDC/ATSDR, will continue to work with the
MDHHS to monitor health issues of Flint residents that may be related to the water system.

40

References
Arndt J, Smith N, Tausk F. 2008. Stress and atopic dermatitis. Current Allergy and Asthma Reports (8):312–
317.
Arnedo-Penn A. Bellido Blasco J, Puig Barbera J, Artero Civera A, Campos Cruanes JB, Pac Sa MR, et al. 2007.
Domestic water hardness and prevalence of atopic eczema in Castellon (Spain) school children. Salud Publica
Mex 49(4):295–301.
[ATSDR] Agency for Toxic Substances and Disease Registry. 2006. Toxicological Profile for nickel. Atlanta, GA:
US Dept. of Health and Human Services. Available from
http://www.atsdr.cdc.gov/ToxProfiles/tp.asp?id=245&tid=44.
ATSDR. 2014. ToxFAQs webpage. Available from http://www.atsdr.cdc.gov/toxfaqs/Index.asp.
[CDC] Centers for Disease Control and Prevention. 2016. Blood lead levels among children aged <6 years
living in the City of Flint, Michigan, 2013–2016. MMWR Early Release 65:1-5.
[DHHS/CDC] Department of Health and Human Services (DHHS), Centers for Disease Control and Prevention
(CDC). 2016. Report to Michigan Department of Health and Human Services: Community Assessment for
Public Health Emergency Response (CASPER) After the Flint Water Crisis, Flint, Michigan. Atlanta, GA: CDC.
[DWSD] Detroit Water and Sewerage Department. 2016. Water Quality Reports. Available from
http://www.detroitmi.gov/How-Do-I/Find/Water-Quality-Reports.
DWSD. 2015a. Water Quality Report, 2014. [Accessed 3 May 2016]. Available from
http://www.glwater.org/wp­
content/documents/our_water_system/water_quality_report/water_quality_report.pdf.
DWSD. 2105b. Water Quality Division Lake Huron Tap water, Averages for Monthly Mineral Analysis.
Provided by the Michigan Department of Environmental Quality.
[EPA] US Environmental Protection Agency. 2016a. Flint Drinking Water Response. Available from:
https://www.epa.gov/flint.
EPA. 2016b. The third unregulated contaminant monitoring rule (USMR3): data summary. Washington, DC:
EPA 815-S-16-001. Available from: https://www.epa.gov/sites/production/files/2015­
11/documents/ucmr3_data_summary.pdf.
EPA. 2016c. Table of regulated drinking water contaminants. Available from: https://www.epa.gov/your­
drinking-water/table-regulated-drinking-water-contaminants#Disinfectants.

41

EPA. 2016d. Secondary drinking water standards: guidance for nuisance chemicals. Available from:
https://www.epa.gov/dwstandardsregulations/secondary-drinking-water-standards-guidance-nuisance­
chemicals.
Hanna-Attisha M, LaChance J, Sadler RC, and Schnepp AC. 2015. Elevated blood lead levels in children
associated with the Flint drinking water crisis: a spatial analysis of risk and public health response. AJPH e1–
e8. Available from: http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.2015.303003.
Laughter D, Istvan JA, Tofte SJ, et al. 2000. The prevalence of atopic dermatitis in Oregon schoolchildren. J Am
Acad Dermotol 43:649-655.
Liu B and Reckhow DA. 2015a. Disparity in disinfection byproducts concentration between hot and cold tap
water. Water Res 70:196-204.
Liu B and Reckhow DA. 2015b. Impact of water heaters on the formation of disinfection by-products. J Amer.
Water Works Assoc 107(6):e328-e338. Available from: http://www.awwa.org/publications/journal­
awwa/abstract/articleid/51448906.aspx .
McNally NJ, Williams HC, Phillips DR, Smallman-Raynor M, Lewis S, Venn A, et al. 1998. Atopic eczema and
domestic water hardness. Lancet 352(9127):527–31.
Michigan Department of Health and Human Services. Institutional Review Board for the Protection of Human
Research Subjects. IRB Log 201602-01-NR. MDHHS Investigation of Rashes Possibly Associated with Flint
Water Exposure. Application received 2/3/2016. Non-research determination notice date 2/3/2016.
Miyake Y, Yokoyama T, Yura A, Iki M, Shimizu T. 2004. Ecological association of water hardness with
prevalence of childhood atopic dermatitis in a Japanese urban area. Environ Res 94(1):33–7.
[MSSS] Michigan Syndromic Surveillance System. Data retrieved 24 April 2016.
Mowad CM, Anderson B, Scheinman P, et al. 2016. Allergic contact dermatitis: patient management and
education. J Am Acad Dermatology 74:1043.
Mozaffari H, Pourpak Z, Pourseyed S, et al. 2007. Quality of life in atopic dermatitis. J Microbiol Immunol
Infect 40:260-264.
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Musculoskeletal and Skin Diseases. Available from:
http://www.niams.nih.gov/health_info/atopic_dermatitis/.
Nutten S. 2015. Atopic dermatitis: global epidemiology and risk factors. Ann Nutr Metab 66(suppl 1):8–16.
Available from http://www.ncbi.nlm.nih.gov/pubmed/25925336.

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Osman M, Hansell AL, Simpson Cr, Hallowell J, and Helms PJ. 2007. Gender-specific presentations for asthma,
allergic rhinitis and eczema in primary care. Prim Care Respir J 16(1):28-35.
Perkin MR, Craven J,Logan K,Strachan D, Marrs T, Radulovic S, Campbell LE, MacCallum SF, McLean WH,Lack
G, Flohr C. 2016. Association between domestic water hardness, chlorine, and atopic dermatitis risk in early
life: A population-based cross-sectional study. J. Allergy Clin Immunol. Available online 28 April 2016, ISSN
0091-6749, http://dx.doi.org/10.1016/j.jaci.2016.03.031
RietschelRL. 2004. Clues to an accurate diagnosis of contact dermatitis. Dermatol Ther 17:224.
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AWWA-WQTC Proceedings; Salt Lake City, UT.
Sorg TJ, Schock MR, and Lytle DA. 1998. Leaching of metals from household plumbing materials: impact of
softeners. Washington, DC: US Environmental Protection Agency, EPA/600/R-98/044 (NTIS 98-147309).
State of Michigan. 2016. Taking Action on Flint Water. Available from: http://www.michigan.gov/flintwater.
Tsai T.F. (2013). Water: Is it an Irritant? In K.P. Wilhelm, H. Zhai, H.I. Maibach (Eds.), Dermatotoxicology, 8th
ed. (pp. 208–211). Boca Raton, FL: CRC Press.
Thomas KS, Dean T, O'Leary C, Sach TH, Koller K, Frost A, et al. 2011. A randomised controlled trial of ionexchange water softeners for the treatment of eczema in children. PLoS Med 8(2):e1000395.
Tollefson MM and Bruckner AL. 2014. Atopic dermatitis: skin-directed management. Pediatrics 134(6):e1735­
e1744.
Uter W, Pfahlbert A, Gefeller O, Geier J, and Schnuch A. 2003. Risk factors for contact allergy to nickel ­
results of a multifactorial analysis. Contact Dermatitis 48(1):33-38.
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http://water.usgs.gov/edu/groundwater-contaminants.html.
Villarroel MA. 2016. Prevalence of children and adults with eczema and other skin problems, nationally and
by selected states, 2010-2014. National Center for Health Statistics. Available from:
http://www.cdc.gov/nchs/data/health_policy/eczema_skin_problems_tables.pdf.
Weinberg HS, Krasner SW, Richardson SD, and Thruston AD. 2002. The occurrence of disinfection by-products
(DBPs) of health concern in drinking water: results of a nationwide DBP occurrence study. Washington, DC:
EPA (EPA/600/R-02/068).
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Available from http://apps.who.int/iris/bitstream/10665/44584/1/9789241548151_eng.pdf.

43

WRc Group. 2011. A review of skin irritation and tap water (WRc Report No. DWI8375.01). Swindon, UK: WRc
Group. Available from: http://dwi.defra.gov.uk/research/completed-research/reports/dwi70-2-257.pdf.

44

Appendices
Appendix A
A1. Flint Water Rash Response Flowchart

EPA: United States Environmental Protection Agency; CDC: Centers for Disease Control and Prevention; DEQ: Michigan
Department of Environmental Quality; DHHS: Michigan Department of Health and Human Services; MDHHS DEH: MDHHS,
Division of Environmental Health; CHECC: MDHHS Community Health Emergency Coordination Center; PCC: Poison Control
Centers.

45

A2. Review of Prior CDC/ATSDR Rash-Related Investigations
The Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease
Registry (ATSDR) have conducted 11 outbreak investigations of illnesses with accompanying rashes since
1954. Five of the investigations contained only initial reports with minimal, preliminary information. An
additional five contained preliminary or final reports detailing investigation methods and results. The
remaining report was essentially a series of case studies.
The smallest investigation, in Fort Wayne, Indiana, had only 14 cases; the largest, in the Federated States of
Micronesia, had 500 cases. Six of the outbreaks were associated with schools or schoolchildren, four were
community-wide, and one was occupational. The majority of the rash outbreaks were likely infectious in
nature, including three outbreaks with evidence for transmission of an unknown virus, two outbreaks of
rubella, and two outbreaks of unknown but suspected infectious agents. Three outbreaks had insect
etiologies: one caused by mites, one likely caused by mites, and one in which the rash illness followed a tick
bite. Only the outbreak of hives had an unidentified environmental cause; it was associated with a wing of a
school building where classrooms had both been flooded and covered in roof dust from construction.
One of the investigations used self-report to obtain cases, and five relied on clinicians identifying affected
individuals. Another method of case identification was a community-wide survey using census data and a
random sampling method.
The majority of the investigations involved questionnaires administered to cases. Two investigations involved
clinical examination of cases, and the third investigation used a dermatologist examination to collect clinical
data. One outbreak investigation comprised several case studies in a narrative format. Environmental and
site investigations were carried out for three of the outbreak investigations. In two of those cases,
entomologists examined plant matter from the worksite (the occupational outbreak) and randomly sampled
homes (a community-wide outbreak) for evidence of mites. In the third, the wing of the school building with
the highest attack rate of rash cases was tested for chemicals that could cause hives. Laboratory work on
clinical specimens was performed for three of the outbreaks, two of which turned out to be rubella. The third
showed evidence of viral infection, but no agent was identified. Five of the outbreak reports reviewed were
only summaries that did not mention environmental or laboratory work.
CDC/ATSDR has also performed an investigation of health effects thought to be caused by increased
chloramines in tap water. This community-wide investigation involved a questionnaire to identify symptoms
and an inspection of home water-treatment systems. Findings of the investigation did not indicate a link
between the changes in water treatment and symptoms.

46

Appendix B
B1. Standardized Questionnaire

Self-reported Rash Symptoms and Exposure to Flint Water
MDHHS Questionnaire

Form Approved
OMB No. 0923-0051
Exp. Date
03/31/2018

Note to the interviewer: script in italics is clarification for you, and is not to be read aloud to the interviewee. Please do not

prompt answers (e.g. read out options “Yes”, “No”, Don’t Know”, “Refused”) unless noted to.

INTRODUCTION SCRIPTS

For people referred through 211/CHECC and home visits:

Hello, my name is _________________________________, and I work for the [Michigan Department of Health and Human

Services/Agency for Toxic Substances and Disease Registry/Centers for Disease Control and Prevention]. We are working with

the [Michigan Department of Health and Human Services/Agency for Toxic Substances and Disease Registry/Centers for

Disease Control and Prevention] looking into reported rash symptoms related to exposure to Flint tap water. We received

your name because you have reported rash symptoms [to the 211 phone number OR to an MDHHS or CDC representative

who visited your home recently]. We would like to ask you some questions about your health, the health of your family, and

your tap water usage. Your answers will help us understand what symptoms have been reported since the City of Flint

switched its water source. The questions will take about 20 minutes. May we go ahead now with the questionnaire?

For people referred through healthcare providers:

Hello, my name is _________________________________, and I work for the [Michigan Department of Health and Human

Services/Agency for Toxic Substances and Disease Registry/Centers for Disease Control and Prevention]. We are working with

the [Michigan Department of Health and Human Services/Agency for Toxic Substances and Disease Registry/Centers for

Disease Control and Prevention] looking into reported rash symptoms related to exposure to Flint tap water. We received

your name because you visited a healthcare provider to report rash symptoms and they forwarded your information to us. We

would like to ask you some questions about your health, the health of your family, and your tap water usage. Your answers

will help us understand what symptoms have been reported since the City of Flint switched its water source. The questions

will take about 20 minutes. May we go ahead now with the questionnaire?

If yes, participation in this questionnaire is voluntary: if you feel uncomfortable answering any question, you do not have to

answer and you may stop the interview at any time. However, any information you can provide will help us immensely.

IF NO, is there a convenient time when I can call you back?

Day: _________________
Time: ________________ AM / PM

Telephone: __________________________________________

CASE No:

Date:

Public reporting burden of this collection of information is estimated to average 20 minutes per response, including the time for reviewing instructions, searching
existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. An agency may not conduct or
sponsor, and a person is not required to respond to a collection of information unless it displays a currently valid OMB control number. Send comments
regarding this burden estimate or any other aspect of this collection of information including suggestions for reducing this burden to CDC/ATSDR Reports
Clearance Officer; 1600 Clifton Road NE, MS D-74 Atlanta, Georgia 30333; ATTN: PRA (0923-0051)

47

Time interview began:

_ _: _ _ AM / PM
Interviewers Initials:

BACKGROUND
1.
First, I would like to ask if you contacted someone to report that you or someone you know had symptoms. Did you
contact any person or organization to report these symptoms?

No

Yes

Don’t know

Refused

1a.
Can you please tell me who you contacted? (check all that apply)
211
Genesee County Health Department
Health care professional
Emergency room
Don’t know
Refused
Other, please explain

__

___

1b.

What prompted you to contact MDHHS or seek medical care?
________________________________________________________________________
________________________________________________________________________

1c.

Are you calling for yourself or for someone else?
Self
Someone else
1d1.

If they are calling for someone else: What is their name and relationship to you?
1d1a. Name:
___
1d1b. Relationship:
___

1d2.
Could I please interview that person / May we continue with the interview?
(If child, ask parent if you can continue on with interview)
Yes, interviewed other person
Yes, interviewed parent or individual on phone who made contact for other person
Contact information: __________________________________________________
No, other person not available

No, refused to be interviewed

2.

First, I have a few questions about you (or your child/friend, if interviewing for another person).
2a.

How old are you?
48

2b.

What is your sex?
Male
Female

2c.

Do you currently work?
No
Yes
Refused
Don’t know
2c1.

IF YES, can you please explain what you do?

_

HISTORY OF ILLNESS
3.
As I mentioned before, we received your name because you reported symptoms. I am going to ask you about these
symptoms.

3a. Did you experience a rash?
No
Yes
Don’t know
Refused

IF YES, on what parts of your body
did the rash occur?
Face
Arms
Feet
Neck
Hands
Other
Torso
Legs
Explain:
_________

IF YES, how big was the rash? (at widest)
0-3 inches
3-5 inches
> 5 inches
Don’t know
Refused

3a1. When did your rash start? Date: ________________
3a1a. Have your symptoms improved, gotten worse, or
stayed the same since October 16, 2015?
(Note: On October 16, 2015, City of Flint switched back to
buying water from Detroit)

Improved
Gotten worse
Stayed the same
Refused
Don’t know

3a2. Do you still have a rash?
No
Yes
Don’t know
Refused
Can you please describe your rash for me?
3a3. Hives (raised patches)?
3a4. Raised bumps?
No
No
Yes
Yes
Don’t know
Don’t know
Refused
Refused

3a5. Dry or flakey skin?
No
Yes
Don’t know
Refused
49

3a6. Itchy skin?
No

Yes

Don’t know

Refused

3a9.

3a7. Painful skin?
No
Yes
Don’t know
Refused

What activities cause the rash to occur?

Washing dishes

Doing laundry

Cooking

Showering
Taking a bath
Using a hot tub

3a8. Other?

__________________________

__________________________

__________________________

__________________________

Drinking water

Other, please explain _________________

3a10.

Once the rash appears, how long does it take to go away? ____________________________

3a11.

What makes the rash feel better? _______________________________________________

3a12.

What makes the rash feel worse? _______________________________________________

Hours

Days

Has not gone away
Don’t know
Refused

3a13.
Were you taking any new medicines when the rash started?
No
Yes
Don’t know
Refused
IF YES, what kind? ____________________________________________________
Did you experience any other symptoms with the rash? Such as…
3b. Numbness or tingling?
IF YES, Where did the numbness or tingling occur?
No
Face

Yes

Neck

Don’t know

Torso

Refused

Arms
Hands
Legs
Feet
Other
Explain_________________
3c.

3d.

Fever?
No
Yes
Don’t know

Refused

Shortness of Breath?

No
Yes
Don’t know

Refused

IF YES, how high?

Time Course

When did your fever
begin?

When did your fever

end?

When did your s.o.b.
begin?

When did your s.o.b.

end?

50

3e.

3f.

3g.

3h.

Wheezing?
No
Yes
Don’t know
Refused

When did your wheezing
begin?

When did your wheezing
end?

When did your diarrhea
begin?

When did your diarrhea
end?

When did the irritation
begin?

When did the irritation
end?

Please describe:

Quantity
(e.g. strands, chunks)

Location on scalp
(e.g. patchy, right side,
etc.)

Please describe:

Time Course
When did this symptom
begin?

Diarrhea?
No
Yes
Don’t know
Refused
Eye Irritation?
No
Yes
Don’t know
Refused
Hair Loss?
No
Yes
Don’t know
Refused

3i.

Anything Else?
No
Yes
Don’t know
Refused

When did this symptom
end?

Now I would like to ask you a few questions about your tap water use.
4.
Is your home on municipal water, that is, do you get your water from the City of Flint?
No
Yes
Refused
Don’t know
4a.

IF NO, can you tell me the source of your tap water?

___

____________

5. Do or did you have contact with Flint Water outside of your home?
No
Yes
Refused
Don’t know
5a.

IF YES, can you please explain where?

___________________
51

5b.

IF YES, when did you start using Flint water at this location? ________________________________

5c.

IF YES, when did you stop using Flint water at this location? _________________________________

5d.

Have your symptoms improved or gone away since you changed your water use at this location?
Improved
Gotten worse
Stayed the same
Have not changed water use
Refused
Don’t know

6. When your symptoms started, did you notice changes in your tap water quality (appearance, taste, smell) at home?
No
Yes
Refused
Don’t know
6a.

IF YES, can you please describe the change in water quality?

7. When your symptoms started, did you notice changes in your water pressure at home?
No

Yes

Refused

Don’t know

7a.

IF YES, did the water pressure:

Increase?

Decreased

8. Are you using a water filter for your water at home?
No
Yes
Refused
Don’t know
8a.

What type of filter are you using at home?
Brita
PUR
Other________________________________________________________________________

8b.

When did you start using the filter?

8c.

Date: __________________________

How are you using your filter? _______________________________________________________

52

9. Are you using a different water source than normal for the following activities?
Washing dishes
Doing laundry
Cooking, explain ____________________________________
Showering
Taking a bath
Using a hot tub
Drinking water, explain _______________________________________________________________________
Brushing teeth, explain _______________________________________________________________________
Other, please explain ________________________________________________________________________
Refused
Don’t know
10. Have you changed your behavior or habits for bathing and/or showering?
No
Yes
Refused
Don’t know
IF YES, can you please explain how your bathing habits have changed in the following ways:
10a. Frequency
Shower less frequently
Shower more frequently
Don’t know
Refused

10b. Length
Shorter showers
Longer showers
Don’t know
Refused

10c. Method
Please explain: (e.g. use of wipes,
sponges)
_________________________________
_________________________________

11. Do you add anything to your water before using it?
No
Yes
Refused
Don’t know
11a. IF YES, please explain what you add (optional: and the amount you use): _________________________________
Ask about amount if it makes sense based on what they are adding

12. Have you changed your tap water use in any other way? _____________________________________________________
13. When did you start making these changes to your tap water use? Date_________________________________________
14.
Have your symptoms improved, gotten worse, or stayed the same since you changed your water use?
Improved
Gotten worse
Stayed the same
Refused
Don’t know
53

15. What most influenced you to start making these changes to your tap water use?
Symptoms
Concerns for health
Media
Doctor’s advice
Other, please explain __________________________________________________________________________
SEEKING CARE
Note: Please ask these questions of all participants, including those referred by Poison Control.
16. Did you seek medical attention for any of the symptoms we just talked about?
No
Yes
Refused
Don’t know
IF NO, it is important that you go see your primary care doctor or a physician for further evaluation. SKIP TO 17.
IF YES:
16a.
Where did you go? (check all that apply)
Primary Care Provider
Emergency Department
Urgent care
Specialist (e.g. dermatologist, eye doctor, etc.)
Alternative health care provider
Other
Explain: ________________________________________________________________________
16b.
Were you hospitalized for this condition?

Yes

No

Refused

Don’t know

16b1.

IF YES, when?

16c.
Did you receive a diagnosis?

No

Yes

Refused

Don’t know

16c1.

IF YES, what was the diagnosis?

16d.
Did you receive treatment?

No

Yes

Refused

Don’t know

54

16d1.

IF YES, what was the treatment?

16e.
Do you give permission for us to speak to your doctor (or dermatologist) and access your medical records about
these visits to your doctor/the hospital? Medical records are very useful and enable us to add additional details to the
information you have already given us. We will not access any other part of your medical records.
No

Yes

Please provide your doctor’s name and contact information

16e1. Name: __________________________________________________

16e2. Phone Number: __________________________________________

17.
Have you tried any treatments or medications on your own?
No
Yes
Refused

Don’t know

17a.

IF YES, what was the treatment?

_____

GENERAL HEALTH
Now I am going to ask you a few questions about your general health.
18. Has a doctor ever told you that you have any chronic health conditions, such as diabetes, heart disease, or lung disease?
No
Yes
Refused
Don’t know
18a. IF YES, what are they?
18b. When were you told about this / these conditions?

Date:

19. Has a doctor ever told you that you have asthma or seasonal allergies?
No
Yes
Refused
Don’t know
19a. IF YES, what are they?
19b. When were you told about this / these conditions?

Date:

20. Has a doctor ever told you that you have a skin condition, including psoriasis, eczema, or dermatitis?
No
Yes
Refused
Don’t know
55

20a. IF YES, what skin conditions?
20b. When were you told about this / these conditions?

Date:

21. Do you have any allergies to metals, foods, or anything else?
No
Yes
Refused
Don’t know
21a. IF YES, what are they?
21b. When were you tested for this / these conditions?

Date:

22. Do you currently take any medications?
No
Yes
Refused
Don’t know
22a. IF YES, what are they?
23. Are you currently a smoker?
No
Yes
Refused
Don’t know
23a. IF YES, how many packs per day?
24. We would like to schedule your home for water testing. EPA water quality experts would visit your home to take water
samples, which would take from 30 to 60 minutes total, from arrival to departure. You must be present in the home
during this time. Would you like the EPA to come test your water? (if someone has already had their water tested say
“Even if you’ve had your water checked already, we are currently rechecking water after the switch back to Detroit water
to focus on skin problems that people are currently having.”)
No
Yes
Refused
Don’t know
24a. IF YES, what is your:
Address:
(Street

City

State

Zip)

Phone Number: ____________________
56

Best Day(s) for Testing:

_____

Please expect a call from an EPA representative to set up a visit to test the water in your home.
We would like to schedule you to see a dermatologist if you are interested. Are you interested in seeing a dermatologist?

No
Yes
Refused
Don’t know
25. Is there anything else that you think I should know about?

That was the last question. Thank you for taking the time to answer our questions.

If you are interested in the results of this questionnaire and additional information on water disinfection, please refer to the
Flint Water website at http://www.michigan.gov/flintwater.

Interview duration: ___________________ minutes

57

B2. Flowchart of Individuals Participating in the Rash Investigation

58

B3. Counts of Individuals Participating in Each Stage of the Investigation by City Ward
a) Individuals interviewed; b) Individuals who participated in water testing; c) Individuals who
participated in a dermatology screening; d) Individuals who participated in all three stages of
the investigation

a

b

c

d

59

B4. Self-reported Rash Onset

a) Year of onset for pre-existing rashes that worsened after October 15, 2015 (n=189);

b) Month of onset for rashes that developed after October 15, 2015 (n=149).

120

b

100

50
40

80

Number

Number

a

60
40

30
20

20

10

0

0
Pre-2014

2014

2015

Year of Onset

Oct 15 Nov 15 Dec 15 Jan 16 Feb 16 Mar 16 Apr 16

Month of Onset

60

Appendix C
C1. Summary Statistics of Metal Concentrations in Residential Water
N

%
Detected

Mean
(ppb)

Median
(ppb)

Std.
Deviation

Min
(ppb)

Max
(ppb)

Aluminum

491

55.9

155

100.0

609

9.0

16,000

Antimony

221

25.1

0.6

0.4

0.4

0.2

1.1

Arsenic

495

56.3

0.7

0.5

0.7

0.2

7.1

Barium

850

96.7

14.9

13.0

15.3

1.1

160

Beryllium

330

37.5

0.1

0.4

0.1

0.1

1.1

Boron

498

56.6

42.5

23.0

114.1

12.0

1,600

Cadmium

250

28.4

1.1

0.4

1.5

0.1

26.0

Calcium

869

98.9

26,896

27,000

7,105

200

96,000

Chromium

171

19.5

0.4

0.3

0.5

0.2

5.2

Copper

856

97.4

86.1

28.0

266.5

1.1

4,800

Iron

568

64.6

223.0

80.0

814

16.0

17,700

Lead

673

76.5

25.1

0.9

177.8

0.1

3,350

Magnesium

869

98.9

8,186

7,885

3,682

48.0

46,000

Manganese

463

52.7

15.6

8.0

156.9

1.1

4,500

Molybdenum

498

56.7

5.6

0.2

5.6

0.3

16.0

Nickel

503

57.2

4.1

2.8

9.1

0.2

110.0

Potassium

847

96.4

1,162

980.0

2,253

59.0

56,000

Selenium

288

32.4

0.5

0.3

0.5

0.3

2.0

Silver

115

13.1

0.2

0.0

1.0

0.0

10.0

Sodium

879

100

6,348

4,700

9,921

3,900

110,000

Thallium

92

10.5

0.2

0.2

0.1

0.1

0.4

Tin

98

11.1

10.6

2.0

16.5

1.3

290.0

Vanadium

359

40.8

0.8

0.5

1.1

0.2

14.0

Zinc

668

75.2

163.2

25.7

988.7

7.3

27,000

Contaminant

61

C2. Summary Statistics of Water Quality Indicators in Residential Water
N

%
Detected

Mean
(ppb)

Median
(ppb)

Std.
Deviation

Min
(ppb)

Max
(ppb)

Alkalinity

195

100

78.3

72.0

37.8

21.0

330

Chloride

342

100

9,860

9,100

4,934

8,280

52,000

Fluoride

342

100

632.2

630.0

76.9

140.0

1,100

Hardness

692

98.0

97.8

100.0

14.5

1.3

115.0

Sulfate

347

100

22,314

21,000

7,574

18,000

98,000

Total Dissolved Solids

191

100

123,403

120,000

14,833

88,000

210,000

Turbidity

13

52.0

0.7

0.4

1.2

0.1

4.7

Inorganic

C3. Temporal Pattern of Total Hardness in Flint Water
300

Total Hardness (as CaCO3) at Flint Water Plant, Post-Treatment, mg/L

Total Hardness (mg CaCO3/L)

Hardness avg
250

200

Hardness max
Hardness min

150

100

50

62

C4. Temporal Pattern of pH in Flint Water
pH at Flint Water Plant, Post-Treatment

pH Level

10.5
10.0

pH avg

9.5

pH max

9.0

pH min

8.5
8.0
7.5
7.0
6.5

C5. Temporal Pattern in Chlorine Levels in Flint Water

Free Chlorine (mg Cl2 /L)

3.5
3.0
2.5
2.0

Free Chlorine (Cl2) at Flint Water Plant, Post-Treatment, mg/L
Cl2 avg
Cl2 max
Cl2 min

1.5
1.0
0.5
0.0

63

C6. Summary of Other Metals Measured in Residential Water (not necessarily known to be
associated with rashes or other skin problems)
%
Detection 1

55.9%

50-200
(SMCL) 2

Antimony

1.1- max
0.6- average

25.1%

6.0
(MCL) 5

None

Barium

160- max
14.9- average

96.7%

2,000
(MCL)5

None

Metal

Concentration
(µg/L)

Aluminum

16,000- max
155- average

6.3% 3

1.1- max
0.10- average

37.5%

4
(MCL)5

None

Boron

1,600- max
42.5- average

56.6%

6,000
(HA lifetime) 7

None

Cadmium

26- max
1.1- average

28.4%

5
(MCL)5

17,700- max
223- average

64.6%

300
(SMCL)2

Concentration
at Detroit
Water Plant
(µg/L)
Max: 142
Average: 52
[Detroit plant tap
water, 2015]

Not detected
(<0.6)
[Detroit plant tap
water, 2008]

Max: 10

Beryllium

Iron

1

%
Exceeding
Evaluation
Level

Drinking Water
Evaluation Level
(µg/L)

1.1%

11.9%

[Detroit plant tap
water, 2008]

Not detected
(<0.4)
[Detroit plant tap
water, 2008]

No levels
available
Not detected
(<0.3)
[Detroit plant tap
water, 2008]

Max: 642
Average: 147
[Detroit plant tap
water, 2015]

Health-based
level (µg/L)

20,000
(RSL-child-nc) 4
4
(ATSDR­
child,nc) 6
2,000
(ATSDR­
child,nc)6
20
(ATSDR­
child,nc)6
4,000
(RSL-child-nc)3
1
(ATSDR­
child,nc)6
14,000
(RSL-child-nc)4

There were 880 total measurements for each metal

SMCL – US EPA Secondary Maximum Contaminant Level (non-mandatory water quality standards established only as guidelines
for aesthetic considerations, such as taste, color, and odor. These contaminants are not considered to present a risk to human
health at the SMCL)

2

3

Detection limit (200 µg/L) is at the Upper SMCL

4

RSL – U.S. EPA Risk-based Screening Level for tapwater exposure – this is a health-based level calculated to make sure people
are not exposed to too much of this chemical from drinking water, skin contact, or breathing in the chemical

4

6

MCL – US EPA Maximum Contaminant Level (the highest level of a chemical that is allowed in drinking water)
ATSDR-health-based comparison value for non-cancer effect for exposure to a child

HA – US EPA Health Advisory Level for Drinking Water (this is a health-based level set to make sure that people are not exposed
to too much of this chemical in their drinking water over a lifetime)

7

64

Metal

Concentration
(µg/L)

Lead

3,350- max
25.1- average

Manganese

4,500- max
15.6- average

Molybdenum

16.0- max
5.6- average

Selenium

2.0- max
0.5- average

Thallium

0.43- max
0.17- average

Tin

290- max
10.6- average

Vanadium

Zinc

14.0- max
0.80- average

27,000- max
163.2- average

%
Detection 1

76.5%

52.7%
56.7%

Drinking Water
Evaluation Level
(µg/L)
15
Action Level for
Lead/ Copper
Rule 8
50
(SMCL)2
300
(HA lifetime)7
40
(HA lifetime)7

%
Exceeding
Evaluation
Level
13.4%

4.3%

None

32.4%

50
(MCL)5

None

10.5%

2 (MCL)5

None

11.1%

No regulatory
limit

Not
applicable

40.4%

4.5
(RDWC) 9

75.4%

5,000
(SMCL)2
2,000
(HA lifetime)7

4.2%

0.9%

Concentration
at Detroit
Water Plant
(µg/L)
Not detected
(<2)
[Detroit plant tap
water, 2015]

Max: 18,
Average: 2
[Detroit plant tap
water, 2015]

No levels
available
Max: 1
[Detroit plant
tap water,
2008]
Not detected
(<0.2)
[Detroit plant
tap water,
2008]
No levels
available
Max: 0.59
Average: 0.19
[Detroit plant
tap water 2014]
Not detected
(<20)
[Detroit plant
tap water,
2015]

Health-based
level (µg/L)

0 (MCLG)

430
(RSL-child-nc)4

100
(RSL-child-nc)4
50
(ATSDR­
child,nc)6

0.2
(RSL-child-nc)4
3,000
(ATSDR­
child,nc)6
86
(RSL-child-nc)4

3,000
(ATSDR­
child,nc)6

Action Level for Lead/Copper Rule – US EPA Lead and Copper Rule (the action levels for the 90th percentile of compliance
samples is based on technical feasibility of reducing lead and copper in drinking water through optimizing corrosion control)

8

9

RDWC- MDEQ Residential Drinking Water Criteria

65

C7. Potential Health Effects Associated with Exposure to Metals Detected in Residential Water
Metal

Arsenic

What is it?

Potential Health Problems

• is a natural element

• skin damage

• is commonly found in water from erosion of
natural deposits

• problem with the circulatory
system
• may increase a person’s risk of
developing cancer

Chromium,
total

• is a natural element
• could be released from steel and pulp mills
• also from erosion of natural deposits
• is a natural element
• is a required nutrient for our bodies to function

Copper

• allergic dermatitis

• is a common metal in water pipes and faucets

• gastrointestinal distress (short­
term exposure)
• liver or kidney damage (long-term
exposure)
• people with Wilson’s Disease
should consult their health care
provider

• is a natural element

Lead

Nickel

Silver

• is a common metal in water pipes made before
1986, solder, and faucets

• can harm brain development in
fetuses and children
• can slow children’s growth

• also can be found in paint, dirt, bullets, fishing
sinkers, make-up and lotions, food, and many
other items

• can cause high blood pressure or
kidney problems in adults

• is a natural element

• allergic dermatitis

• is used in stainless steel and alloys

• stomachaches (high amounts)

• can also be found in electroplating, mining, and
refining metals

• damage to blood and kidneys
(high amounts)

• is a natural element

• skin discoloration (cosmetic
effect)

• is used in alloys, solder, electronics and
electrical equipment, and other products
• could be released from ore mining and
processing, product fabrication, electroplating

• graying of the white part of the
eye (cosmetic effect)
• allergic dermatitis
66

Metal

What is it?
• is a natural element

Thallium

• is used in electronics and alloys
• could also be released from pharmaceutical
manufacturing

Potential Health Problems
• hair loss (high amounts in a short
time)
• kidney, intestine, or liver
problems (high amounts in a
short time)

(EPA 2016c, EPA 2016d, Sorg et al. 1998, ATSDR 2014, USGS 2016)

C8. Aesthetic or Cosmetic Issues Linked to Metals and Water Parameters
Metal or Water Parameter

What is it?

Potential Problems

• is a natural element

Aluminum

• can be found in beverage
cans, foil, antacids, and
other consumer products

• discolored water

• also is mixed with other
metals to form aluminum
alloys
• is a natural element
Copper

• is a required nutrient for
our bodies to function
• is a common metal in water
pipes and faucets

• metallic taste
• blue-green staining

• rusty colored water
Iron

• is a natural element

• sediment
• metallic taste
• reddish or orange staining

• is a natural element
• is used in steel production
Manganese

• is commonly found in water
from erosion of natural
deposits

• black to brown colored water
• black staining
• bitter metallic taste

67

Metal or Water Parameter

What is it?

Potential Problems

• is a natural element

Silver

• is used in alloys, solder,
electronics and electrical
equipment, and other
products
• could be released from ore
mining and processing,
product fabrication,
electroplating

• skin discoloration (cosmetic effect)
• graying of the white part of the eye
(cosmetic effect)

• is a natural element

Zinc

• commonly found in water
from erosion of natural
deposits or from mining

• metallic taste

• common metal in water
pipes and faucets
(EPA 2016c, EPA 2016d, Sorg et al. 1998, ATSDR 2014, USGS 2016)

C9. Disinfection Byproducts and Other Organics Pilot Project
In the course of the investigation, it was decided that there should be an initial evaluation of additional
chemical compounds that could be present in Flint drinking water. A pilot study was developed to evaluate
the presence of a wide range of organic chemicals, including chemicals known as disinfection byproducts. Six
homes (where residents complained of rash concerns, were surveyed, and were scheduled for dermatological
appointments) were recruited to participate in the additional testing. Five homes (where there was a request
to EPA for water sampling, but where no concerns about rashes among the residents) were selected as
comparison homes. The water samples were tested for disinfection byproducts (DBPs), including
trihalomethanes (THMs), haloacetic acids (HAAs), and haloacetonitriles; volatile organic compounds, and
semi-volatile compounds.
The results of the organic chemical testing (shown below in Tables C9-1, C9-2, and C9-3) for the rash homes
were compared to the comparison homes, to regulatory values for Total THMs and HAAs, and to levels for
these compounds that have been reported in the scientific literature. The results indicate that all of the
values for the rash homes and the comparison homes are below federal standards for DBPs. In addition, all
of the results indicate that the levels of organic chemicals found in the residential water samples are within
expected ranges that have been reported for chlorinated water systems.

68

Acetone was detected in several rash (max= 170 µg/L; average= 34 µg/L) and control (max= 16 µg/L;
average= 8.6 µg/L) samples. The apparent difference in the acetone concentration between the rash and
control group was the contribution of one rash home, where the acetone concentration was elevated for
both hot and cold water. This result is clearly different from all of the other samples analyzed for volatile
organic compounds, and there is no obvious explanation for this elevated reading. However, even this
acetone level is well below the level that would be a concern for ingestion of water or likely to have effects
on the skin.

Table C9-1. Pilot Project: Summary of Trihalomethane Concentrations in Control and Rash Residences
Contaminant

Control Group (n=5)
Max (µg/L)
Mean (µg/L)
Cold
Hot
Cold
Hot

Rash Group (n=6)
Max (µg/L)
Mean (µg/L)
Cold
Hot
Cold
Hot

Chloroform
Bromodichloromethane
Dibromochloromethane
Bromoform

13.4
6.0
2.0
nd*

36.0
10.5
3.0
nd

9.3
5.2
1.8
nd

23.1
8.3
2.6
nd

13.1
6.2
2.1
Nd

46.8
13.1
3.9
nd

9.0
5.2
1.8
nd

29.4
9.2
2.8
Nd

21.3

47.8

16.3

34.0

20.8

63.9

15.9

41.4

Total THMs
*nd = non-detect

Table C9-2. Pilot Project: Summary of Haloacetic Acid Concentrations in Control and Rash Residences
Contaminant

Control Group
Max (µg/L)
Mean (µg/L)
Cold
Hot
Cold
Hot

Rash Group
Max (µg/L)
Mean (µg/L)
Cold
Hot
Cold
Hot

pH
Chlorine residual
1,2,3-Trichloropropane
2-Bromobutanoic acid
Bromodichloroacetic acid (BDCAA)
Chlorodibromoacetic acid (CDBAA)
Tribromoacetic acid
Dibromoacetic acid
Dichloroacetic acid
Monobromoacetic acid
Monochloroacetic acid
Trichloroacetic acid

7.4
0.7
1.0
10.0
2.9
nd
nd
nd
17.2
nd
nd
5.4

Total Haloacetic acids (HAA5)

22.7

1.0
10.0
2.9
nd
nd
nd
12.3
nd
nd
6.1

7.2
0.5
1.0
9.8
2.4
nd
nd
nd
9.7
nd
nd
4.1

1.0
9.8
2.2
nd
nd
nd
8.8
nd
nd
4.1

7.2
0.7
1.0
10.0
2.9
nd
nd
nd
11.7
nd
nd
5.3

16.5

13.8

12.9

17.0

1.0
9.9
2.0
nd
nd
nd
13.8
nd
nd
4.9

7.2
0.6
1.0
9.6
2.6
nd
nd
nd
8.3
nd
nd
4.2

1.0
9.6
2.0
Nd
Nd
Nd
8.6
Nd
Nd
3.4

18.7

12.5

12.0

69

Table C9-3. Pilot Project: Summary of Haloacetonitrile Concentrations in Control and Rash Residences
Contaminant

Control Group
Max (µg/L)
Mean (µg/L)
Cold
Hot
Cold
Hot

Rash Group
Max (µg/L)
Mean (µg/L)
Cold
Hot
Cold
Hot

1,1,1-Trichloro-2-propanone
1,1-Dichloro-2-propanone
Bromochloroacetonitrile
Chloropicrin
Dibromoacetonitrile
Dichloroacetonitrile
Trichloroacetonitrile
Chloral hydrate

1.9
0.4
0.7
0.3
0.2
1.6
nd
4.4

1.6
0.3
0.6
0.3
0.2
1.5
nd
3.2

0.3
0.6
0.6
0.3
0.2
1.1
nd
7.5

1.3
0.3
0.6
0.2
0.2
1.3
nd
2.4

0.2
0.3
0.3
0.2
0.2
0.6
nd
2.7

0.2
0.4
0.6
0.4
0.2
0.9
nd
5.1

1.1
0.3
0.6
0.2
0.2
1.2
nd
2.0

0.2
0.3
0.3
0.2
0.2
0.5
Nd
2.3

70

C10. Summary of Comparison Values for Disinfection Byproducts in Residential Drinking Water
Water Quality
Parameter

EPA,
2002 10
(range
: µg/L)

WHO,
2011
11

(µg/L)

Liu and
Reckow
, 2015 12
(µg/L)

Liu and
Reckow
, 2015 13
(µg/L)

AWWA­
WQTC,
2015 14

EPA
MCL
(µg/L)
15

EPA
Health
Advisor
y
(µg/L) 16

EPA
RSL
(µg/L)

ATSDR
(µg/L)
18

WHO
(µg/L
)

17

Chloroform

27-41

10
(cold)
38 (hot)

70

0.22 (c)
97 (nc)

100
(nc­
child)

300

Bromodichloromethane

4.7-36

2.5
(cold)
5.5 (hot)

100
(DWEL)

0.13 (c)
380
(nc)

0.56 (c)
200
(nc­
child)

60

Bromoform

nd-2

1,000
(DWEL)

3.3 (c)
380
(nc)

4.4 (c)
200
(nc­
child)

100

Dibromochloromethane

0.7-14

60

0.87 (c)
380
(nc)

900
(nc­
child)

100

Total Trihalomethanes

38-86

Bromochloroacetonitril
e
Dibromoacetonitrile
Dichloroacetonitrile
(DCAN)

0.3-2

na

na

Na

nd-0.1
2.8-8

na
na

na
na

70
20

Trichloroacetonitrile

nd-0.1

na

na

Na

Chloral Hydrate

6.9-15

na

na

100

30
(median
)

<100

0.3
(cold)
0.7 (hot)
12
(cold)
42 (hot)

25
(cold)
38 (hot)

1.8
(cold)
0.1 (hot)
<10

80

10

Weinberg HS et al. 2002. The Occurrence of Disinfection By-Products (DBPs) of Health Concern in Drinking Water: Results of a

Nationwide DBP Occurrence Study. EPA/600/R-02/068 (Distribution Systems data summarized from Tables 9,11,13, 15 for Plant 4

using Chlorine Disinfection).

11
World Health Organization. 2011. Guidelines for Drinking-Water Quality, 4th Edition. Geneva, Switzerland: WHO.

12
Liu B and Reckhow DA. 2015. Disparity in Disinfection Byproducts Concentration between Hot and Cold Tap Water. Water

Research 70:196-204.

13
Liu B and Reckhow DA. 2015. Impact of Water Heaters on the Formation of Disinfection By-products. J Amer Water Works Assoc

2015.107.0080.

14
Samson C, Seidel C, Bartrand T and Via S. 2015. Assessing DBP Occurrence: Impacts of the Stage 2 DBPR. AWWA-WQTC

Proceedings; Salt Lake City, UT (Summary of more than 10,000 testing results reported by water suppliers nationally).

15
EPA Maximum Contaminant Level represents the federal drinking water standard (https://www.epa.gov/dwstandardsregulations).

16
EPA Health Advisory Level (https://www.epa.gov/dwstandardsregulations).

17
EPA Regional Screening Levels.

18
ATSDR Screening Levels, based on Minimal Risk Levels (http://www.atsdr.cdc.gov/mrls/index.asp).

71

Water Quality
Parameter

EPA,
2002 10
(range
: µg/L)

WHO,
2011

Chloropicrin

0.2-0.6

<5

1,1-Dichloro-2­
propanone
1,1,1-Trichloro-2­
propanone (TCP)

1

Dibromoacetic acid
(DBAA)
Dichloroacetic acid
(DCAA)

nd-2.9

Monobromoacetic acid
(MBAA)
Monochloroacetic acid
(MCAA)
Trichloroacetic acid
(TCAA)

nd

20-35

8 (cold)
8 (hot)

8 (cold)
8 (hot)

Bromochloroacetic acid
(BCAA)

1.7-7.3

Bromodichloroacetic
acid (BDCAA)

3.6-12

0.7
(cold)
1.0 (hot)
0.7
(cold)
1.2 (hot)

0.8
(cold)
0.9 (hot)
0.45
(cold)
0.3 (hot)

Tribromoacetic acid
(TBAA)

nd

11

(µg/L)

Liu and
Reckow
, 2015 12
(µg/L)

Liu and
Reckow
, 2015 13
(µg/L)

AWWA­
WQTC,
2015 14

EPA
MCL
(µg/L)
15

EPA
Health
Advisor
y
(µg/L) 16

nd
(cold)
0.6 (hot)

nd-7.8

ATSDR
(µg/L)
18

WHO
(µg/L
)

17

0.83 (n)

Na

na
1.8
(cold)
<0.1
(hot)

17-25

EPA
RSL
(µg/L)

<20

5 (cold)
15 (hot)

na

na

na

79 (nc)
1.5(c)

0.7 (c)

na

na

0.07

na

na

20

390
(nc)
1.1 (c)
na

0.5 (c)

na

na

na

na

10
(cold)
15 (hot)
20

2.1

60

50

na

72

Appendix D
D1. Dermatologic Assessment Form

Flint Dermatological Assessment Investigation
Date: _________

ID: ____

Name of Person Evaluated: ___________________________________________ Phone number: _________________
Street Address: _____________________________________ City: ______________ State: _____ Zip: ____________
Primary Care Provider
Name: _______________________
City: ________________________
Phone: ______________________
Fax: _________________________

Information Provided to Person Evaluated

(initial):

_________
I received the

□ Signed Medical/HIPAA Release Form
following documents:
□ Dry Skin Tips – American Academy of Dermatology/CDC
□ Copy of letter to Primary Care Provider about evaluation
□ Copy of general tips for Primary Care Provider about managing eczema
□ Copy of Dermatological Assessment Form sent to Primary Care Provider
□ Other: ____________________________________________________

DEMOGRAPHICS
DOB: __/ __ / __ Sex: □ Male □ Female □ N/A Occupation: ________________ Ethnicity: □ Hispanic □ Not Hispanic
Race: □ American Indian/ Alaskan Native

□ Asian

□ Black

□ Native Hawaiian/ Pacific Islander

□ White

HISTORY OF PRESENT ILLNESS

Chief Complaint: ____________________________________________________________________________________

Symptoms
__________________
__________________
__________________
__________________

Onset
______
______
______
______

Location
_______________________
_______________________
_______________________
_______________________

Aggravating factors: □ Showering □ Bathing □ Washing hands

Duration
__________
__________
__________
__________

Severity/Characteristics

_______________________________
________________________________
________________________________
________________________________

□ Other: __________________________________

Alleviating factors: __________________________________________________________________________________
Notes: ____________________________________________________________________________________________
__________________________________________________________________________________________________

73

PREVIOUS TREATMENTS FOR CURRENT CONDITIONS / EFFECTIVENESS

PAST DERMATOLOGIC HISTORY
□ Dry/Sensitive skin
□ Eczema
□ Psoriasis
□ Skin infections
□ Alopecia

Description
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________
_____________________________________________

Onset Date
__________
__________
__________
__________
__________

Status
___________________
___________________
___________________
___________________
___________________

Notes/other: _______________________________________________________________________________________

PAST MEDICAL HISTORY
□ Asthma □ Autoimmune disease: _________________ □ Allergies (seasonal, meds, metals, etc):_________________
□ Notes/other: _____________________________________________________________________________________
CURRENT MEDICATIONS (Prescription and over the counter)

PHYSICAL EXAMINATION
Vital Signs (if obtained) ___________________________________________________________

□ Photo(s) taken

Skin Examination – Circle and identify findings, Size (BSA), Important characteristics:

Notes: ____________________________________________________________________________________________
__________________________________________________________________________________________________
74

ASSESSMENT OF RELATIONSHIP OF SKIN CONDITION TO WATER EXPOSURE (Circle)
Definitely unrelated
Possibly related
Probably related
Definitely related

Unknown

ASSESSMENT/DIAGNOSES

RECOMMENDATIONS

Signature: ______________________________________________ Date:_________________

Physician (circle): Bishr Al Dabagh, MD - Walter Barkey, MD - Kevin Gaffney, MD - Robert Soderstrom, MD

I understand that I have a skin condition that requires a follow-up examination. I also understand that it is my responsibility
arrange for a follow-up examination with my primary care provider, and any further evaluation and treatment by a

dermatologist will be coordinated by my primary care provider.

______________
Examinee initials

75

D2. Dermatologic Diagnoses, by Category
Clinical Categories
1) Diagnoses definitely
unrelated to exposure to
Flint municipal water

2) Dermatitis possibly
related to water
exposure

3) Non-dermatitis skin
conditions possibly
associated with water
exposure

N (%)
1. Tinea capitis
2. Granuloma annulare
3. Multiple scalp actinic keratoses
4. Tinea cruris / onychomycosis
5. Id eruption (autoeczematization) secondary to URI
6. Localized pustular psoriasis of the palms and soles (2)
7. Chronic plaque type psoriasis
8. Tinea versicolor (KOH positive)
9. Scabies (2)
10. Morbilliform drug rash secondary to sulfa
11. Allergic contact dermatitis to a product used to resurface countertops
12. Pseudofolliculitis barbae (2)
13. Skin picking syndrome (dermatitis artefacta)
14. Milia
15. Tinea incognito
16. Intertrigo
17. Seborrheic dermatitis
18. Arthropod bite (unrelated temporally to water)
1. Eczematous dermatitis (9)
1a. asteatotic eczema (13)
1b. atopic dermatitis (16)
1c. hand eczema (2)
1d. hyperkeratotic eczema of the palms/soles
1e. nummular dermatitis (3)
1f. Eczema craquele
2. Psoriasiform dermatitis
3. Seborrheic dermatitis with eczematous component (3)
4. Contact dermatitis
5. Lichen simplex chronicus (4)
6. Intertrigo
1. Resolving abscess vs ruptured epidermal inclusion cyst (culture
negative)
2. Acquired ichthyosis
3. Telogen effluvium (2)
4. Generalized pruritus without rash (6)
5. Chronic folliculitis (2)
6. Urticaria (2)
7. Prurigo papularis (2)
8. Arthropod assault reaction (still listed as possibly related because it
was worse with exposure and better with avoidance of Flint water)
9. Papular urticaria
10. Seborrheic dermatitis / intertriginous dermatitis
11. Symptomatic dermatographism (2)

24 (19.8%)

53 (43.8%)

27 (22.3%)

76

12. Scarring alopecia c/w central centrifugal cicatricial alopecia (2)
13. Alopecia areata/totalis
14. Vulvar / perineal / perianal dysesthesias without objective findings
15. Urticarial dermatitis (2)
16.Erythema ab igne
17.Acneiform eruption of uncertain etiology
18.Localized dysaethesia (temporally related to water change)
4) Resolved/inactive rash
possibly associated with
water exposure

1. Resolved eczematous dermatitis (3)
2. Resolved pruritic localized papular eruption
3. Post inflammatory hyperpigmentation/changes (2)
4. Resolved asteatosis (2)
5. Resolved atopic dermatitis (3)
6. Resolved contact dermatitis
6. Resolved eruption/rash of uncertain etiology (2)
7. Resolved folliculitis/cellulitis
8. Resolved generalized pruritus (possibly associated with red papules) (2)
10. Resolved hair loss

17 (14.0%)

Note – One individual had no skin condition based on clinical assessment, several individuals had more than one
diagnosis but were classified by the principal diagnosis.

77

D3. Demographics: Interviews, Water Testing, and Dermatologic Screening

n

%

Total

n

%

Total

Received
Dermatologic
Screening
n
%
Total

Age Groups
<5
5-17
18-64
65+

28
56
237
67

7.2
14.4
61.1
17.3

388
388
388
388

15
29
137
30

7.0
13.6
64.3
14.1

213
213
213
213

9
11
80
22

7.4
9.0
65.6
18.0

Female

254

65.1

390

142

66.7

213

71

Demographic
of Interest

All Case Interviews

Received Water
Testing

Population of Flint, MI
US Census data, 2010
n

%

Total

122
122
122
122

8,177
19,737
63,521
10,999

8.0
19.3
62.0
10.7

102,434
102,434
102,434
102,434

58.2

122

53,294

52.0

102,434

Black

not collected

not collected

70

57.4

122

57,939

56.6

102,434

Hispanic

not collected

not collected

1

2.8

36

3,976

3.9

102,434

10,653*

5.8*

182,886*

Unemployed
Adults

213

72.0

296

114

70.8

161

67

67.7

99

Reported
Skin
Conditions

71

18.2

390

48

22.5

213

26

21.3

122

not collected

Reported
Metal
Allergies

15

3.8

390

8

3.8

213

6

4.9

122

not collected

120

not collected

Reported
175
45.7
383
92
44.2
208
54
45.0
Hair Loss
*Statistics for Flint Metropolitan area in 2015 from Bureau of Labor Statistics
(http://data.bls.gov/pdq/SurveyOutputServlet), not the US Census Bureau
(http://www.census.gov/quickfacts/table/PST045215/2629000)

78

D4. Tables of Dermatologic Data

Table D4-1. Severity of Rash for Each Clinical Category (n=80)*

Clinical category
Severity
2
3
n
n
%
%
Mild
39
73.6 12
44.4
Mild-Moderate
8
15.1 10
37
Severe
6
5
11.3
18.5
*Severity was only determined for categories 2 and 3
Table D4-2. Racial and Temporal Distribution of Rash Clinical Category (N=122)
Race
Onset
before
after
Clinical category
White
Black
October
October 16,
Missing
16, 2016
2016
n
%
n
%
n
%
n
%
n
%
1
2
3
4

15
21
8
6

TOTAL

51

29.4
41.2
15.7
11.8

9
31
19
11

12.9
44.3
27.1
15.7

70

14
33
19
8

18.9
44.6
25.7
10.8

74

9
12
6
6

26.5
35.3
17.6
17.6

34

1
8
2
3

7.1
57.1
14.3
21.4

14

Table D4-3. Racial and Temporal Distribution of Rash Severity (n=80)*
Race
White

Severity

Black

before
October
16, 2016

Onset
after
October
16, 2016

Missing

n

%

n

%

n

%

n

%

n

%

Mild
Mild-Moderate
Severe

20
3
6

69.0
10.3
20.7

31
15
4

62.0
30.0
8.0

32
12
8

61.5
23.1
15.4

11
6
1

61.1
33.3
5.6

8
0
2

80.0
0
20.0

TOTAL

29

50

52

18

10

*Clinical categories 2 and 3 only

79

Table D4-4. Distribution of Recommended Topical Steroids Strength
n
%
Topical Steroid Classification Group
35
50.0
Medium (group 4)
11
15.7
Lower-mid (group 5)
9
12.9
Lowest (group 7)
8
11.4
Super high (group 1)
3
4.3
Low (group 6)
3
4.3
High (group 2)
1
1.4
High (group 3)
70
100.0
TOTAL
*Several individuals were prescribed two classes of steroids

80

Appendix E
E1. Description of Statistical Methods Used to Analyze Combined Data
The distribution of the data for the levels of select contaminants was evaluated using a Shapiro-Wilks test to
determine the normality of the data within the not possibly related and possibly related rash groups. The results
from this test and an assumption of the independence between the two groups were used to determine that a
Wilcoxon Mann Whitney test could be used to evaluate the possible relationships between an individual’s
exposure to different levels of select contaminants and the their rash diagnoses.
An initial test for the normality of the distribution of the two populations (unrelated and possibly related) for each
selected contaminant was performed using a Shapiro-Wilks test. The null hypothesis for this test proposes that the
true population is normally distributed around the population mean. A significance alpha value of 0.05 was used to
evaluate the resulting p-values of this test. The contaminants’ p-values for the Shapiro-Wilks test that were less
than 0.05 provided enough statistical evidence to reject the null hypothesis with 95% confidence that the finding
was not by chance. After observing the results of the test, all but one of the clinical category groups rejected the
null hypothesis that the data was from a normal distribution. These results were used to determine that a
statistical test for non-normally distributed data could be considered.
The two populations separated into the unrelated and possibly related groups were deemed to be independent
even though some individuals lived in the same household. Since each patient was given one clinical category for
his or her rash diagnoses, each individual could be independently matched up with a household reading for the
measurements across the selected contaminants, and all individuals would be considered independent of one
another.
Since the majority of the data was not normally distributed and the samples were assumed to be independent, a
Wilcoxon Mann Whitney test was conducted. The null hypothesis for this test states that the true population
means of the unrelated and possibly related groups are the same. While this test uses rank methodologies to
compare the means across the two groups, the raw values of these contaminant concentrations were recorded for
the unrelated and possibly related rash groups (Table E2). Normality approximations were taken due to a
computational software limitation that inhibited exact values to be calculated in the amount of time available to
conduct this analysis. Exact values would be ideal, but this approximation would suffice if more samples could be
collected to create a more normal distribution within the two populations.
In order to utilize these exact methodologies, different clinical category combinations within the unrelated and
possibly related groups were compared using the same Wilcoxon Mann Whitney analysis in scenarios that limited
the readings to only hot water. These comparisons limited the number of samples so that exact methods could be
more feasibly conducted in a reasonable amount of time.
Table E2 shows the comparison of average concentrations of specific contaminants detected in all samples (hot
and cold) that had been initially determined to be of a potential interest for skin effects, comparing the Clinical
Categories of Unrelated (#1 and #5) with the Possibly Related Categories (#2, #3, #4). Table E3 is a comparison of
the descriptive statistics for contaminant concentrations among Clinical Category 1, 2, and 3. Most average values
were no different between the groups. Some comparisons were statistically significant, but no findings were
determined to be clinically significant..

81

Table E2. Average Concentrations for Select Contaminants comparing Clinical Categories for
Rashes Not Possibly Related Versus Rashes Possibly Related 1,2
Contaminant

Unrelated

Possibly Related

Arsenic

0.3

0.4

Chromium

0.4

0.5

Copper

75.0

81.5

Hardness

98.7

98.9

Nickel

1.2

3.5

Silver

0.0

0.4

Thallium

0.2

0.2

Zinc

166.5
of cold and hot water samples
2Units are mg/L

357.8

1Combination

Table E3. Comparison of Contaminant Water Concentrations for Different Clinical Categories 3
Clinical
Category

N

Alkalinity

1

13

67.8

71

70.0

72.0

21

79

14.3

Alkalinity

2

38

72.6

72

70.0

74.0

68

80

3

Alkalinity

3

15

74.1

74

71.0

78.0

69

80

3.5

Aluminum

1

9

49.2

26

21.0

49.0

18

150

45.9

Aluminum

2

19

60.7

35

21.0

78.0

15

224

56.9

Aluminum

3

12

161.2

47.5

23.5

180.0

17

780

237.3

Antimony

1

3

0.2

0.2

0.2

0.2

0.2

0.2

0

Antimony

2

4

0.2

0.2

0.2

0.3

0.2

0.3

0.1

Antimony

3

7

0.3

0.2

0.2

0.5

0.2

0.6

0.2

Arsenic

1

8

0.2

0.2

0.2

0.3

0.2

0.3

0

Arsenic

2

18

0.3

0.3

0.2

0.3

0.2

0.4

0.1

Arsenic

3

12

0.3

0.3

0.2

0.4

0.2

0.5

0.1

Barium

1

13

13.4

13.4

13.0

14.0

11

15

1

Barium

2

42

13.4

13

12.4

14.0

11.4

16

1.1

Barium

3

16

14

13.2

13.0

15.0

12

19

1.8

Beryllium

1

6

0.2

0.2

0.1

0.4

0.1

0.4

0.1

Contaminant

3

Mean
(µg/L)

Median
(µg/L)

Q_25
(µg/L)

Q_75
(µg/L)

Min
(µg/L)

Max
(µg/L)

Std_Dev

Hot water samples

82

Clinical
Category

N

Beryllium

2

7

0.2

0.1

0.1

0.3

0.1

0.4

0.1

Beryllium

3

9

0.1

0.1

0.1

0.2

0.1

0.3

0.1

Boron

1

9

19

17

15.0

19.0

13

34

6.6

Boron

2

18

21.2

18

15.0

20.0

15

43

8.6

Boron

3

12

27.5

20

17.5

23.0

14

87

21.5

Cadmium

1

2

0.3

0.3

0.1

0.4

0.1

0.4

0.2

Cadmium

2

5

0.3

0.2

0.2

0.3

0.2

0.4

0.1

Cadmium

3

6

0.9

0.3

0.2

0.9

0.1

3.3

1.2

Calcium

1

13

26453.8

26300

26000.0

27000.0

25000

28100

774.2

Calcium

2

42

26600

27000

26000.0

27200.0

24400

28100

1016.2

Calcium

3

16

26412.5

26000

25500.0

27600.0

25000

28000

1100.8

Chloride

1

13

9233.8

9200

9040.0

9500.0

8860

9500

233.4

Chloride

2

38

9151.6

9100

9000.0

9320.0

8470

9800

298.3

Chloride

3

15

9142.7

9140

9000.0

9280.0

8900

9400

146.6

Chromium

2

6

0.2

0.2

0.2

0.3

0.2

0.4

0.1

Chromium

3

3

0.2

0.2

0.2

0.2

0.2

0.2

0

Copper

1

13

43.6

29

18.0

49.9

4.5

170

44.4

Copper

2

42

34.9

30.7

16.2

44.6

4.5

110

24.8

Copper

3

16

35.5

34

14.2

39.1

5.8

99

25.1

Fluoride

1

13

656.9

670

610.0

680.0

570

720

47.1

Fluoride

2

38

611.1

610

570.0

650.0

510

710

49.9

Contaminant

Fluoride

Mean
(µg/L)

Median
(µg/L)

Q_25
(µg/L)

Q_75
(µg/L)

Min
(µg/L)

Max
(µg/L)

Std_Dev

3

15

597.3

610

500.0

670.0

480

700

78.6

4

1

13

99

99.2

96.6

101.1

93.7

104.1

2.9

Hardness4

2

42

99.3

99.9

97.0

101.5

89.2

105.5

3.7

Hardness4

3

16

99.6

100.3

95.5

103.6

93.7

104.8

4.3

Iron

1

8

52.1

33.5

20.5

84.4

17

123

39.8

Iron

2

18

88.7

70.5

40.0

131.0

23

210

52.8

Iron

3

14

139.1

114

53.0

190.0

25

340

105.3

Lead

1

12

0.6

0.4

0.2

0.9

0.1

2.2

0.6

Lead

2

24

3.2

0.7

0.5

1.3

0.4

20

6.3

Lead

3

14

4.1

0.8

0.4

8.3

0.3

20

6.2

Hardness

4

Units are mg/L

83

Contaminant

Clinical
Category

N

Mean
(µg/L)

Median
(µg/L)

Q_25
(µg/L)

Q_75
(µg/L)

Min
(µg/L)

Max
(µg/L)

Magnesium

1

13

8021

8100

7700

8200

7600

8800

374.9

Magnesium

2

42

8004

8000

7800

8190

6870

9260

408.9

Magnesium

3

16

8194

8315

7750

8510

7600

9100

453

Manganese

1

6

3.7

2.1

1.9

3.3

1.8

11

3.6

Manganese

2

14

7.8

4

2.6

9.0

1.1

31

8.8

Manganese

3

15

10.8

8.6

2.6

17.7

1.5

38

9.9

Molybdenum

1

9

0.5

0.5

0.5

0.6

0.5

0.6

0

Molybdenum

2

18

0.5

0.5

0.5

0.5

0.3

0.6

0.1

Molybdenum

3

12

0.6

0.5

0.5

0.6

0.5

0.7

0.1

Nickel

1

8

1.1

0.8

0.8

1.3

0.5

2.7

0.7

Nickel

2

17

1.2

0.8

0.6

1.6

0.5

3.6

1

Nickel

3

13

4.2

2.5

0.8

4.1

0.3

14.1

4.8

Potassium

1

13

962

960

950

980

890

1030

36.6

Potassium

2

36

986

980

945

1000

890

1200

66.7

Potassium

3

16

978

981

935

1000

900

1100

55.9

Selenium

1

4

0.4

0.3

0.3

0.5

0.3

0.7

0.2

Selenium

2

7

0.5

0.6

0.4

0.6

0.3

0.9

0.2

Selenium

3

9

0.6

0.5

0.3

0.8

0.3

1.6

0.4

Silver

2

1

0

0

0.0

0.0

0

0

.

Silver

3

2

5

5

0.0

10.0

0

10

7.1

Sodium

1

13

4715

4700

4700

4800

4400

5130

172

Sodium

2

42

4802

4800

4700

4940

4400

5200

213

Sodium

3

16

4730

4700

4600

4875

4400

4990

175

Sulfate

1

13

21562

21000

21000

22000

19200

26000

1958

Sulfate

2

38

21468

21000

20000

23000

18800

25000

1902

Sulfate

3

15

21773

21000

20700

23000

20000

25000

1524

Thallium

1

1

0.1

0.1

0.1

0.1

0.1

0.1

.

Thallium

2

1

0.1

0.1

0.1

0.1

0.1

0.1

.

Thallium

3

1

0.2

0.2

0.2

0.2

0.2

0.2

.

Tin

3

3

1.9

1.9

1.8

2.1

1.8

2.1

0.2

TotalDissolved
Solids

1

10

124000

121000

112000

130000

110000

150000

13433

Std_Dev

84

Clinical
Category

N

Mean
(µg/L)

Q_25
(µg/L)

Q_75
(µg/L)

Min
(µg/L)

Max
(µg/L)

TotalDissolved
Solids

2

23

124521

122000

116000

130,000

102000

158000

13594

TotalDissolved
Solids

3

9

139556

130000

122,000

150,000

116000

210000

29577

Turbidity

2

5

0.4

0.4

0.3

0.6

0.3

0.6

0.1

Vanadium

1

7

0.4

0.4

0.3

0.4

0.3

0.5

0.1

Vanadium

2

17

0.3

0.3

0.3

0.4

0.2

0.6

0.1

Vanadium

3

12

0.5

0.4

0.4

0.6

0.2

0.7

0.2

Zinc

1

9

56.7

32

17.4

53.0

12

160

57.4

Zinc

2

19

86.7

36

13.0

74.0

7.6

420

124.9

Zinc

3

15

177.9

63

12.4

122.0

12

1800

451.4

Contaminant

Median
(µg/L)

Std_Dev

*Q_25 represents the first quartile or the median of the lower half of the data set. This means that about
25% of the numbers in the data set lie below this number and about 75% lie above it. Q-75 represents the
third quartile or the median of the upper half of the data set. This means that about 75% of the numbers in
the data set lie below this number and about 25% lie above it.

85