Download:
pdf |
pdfAttachment 7 EI Report Example
Health Consultation
Exposure Investigation
Biological Testing for Exposure to Lead
FORMER UNITED ZINC & ASSOCIATED SMELTERS
IOLA, KANSAS
AUGUST 15, 2018
U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Agency for Toxic Substances and Disease Registry
Division of Community Health Investigations
Atlanta, Georgia 30333
Health Consultation: A Note of Explanation
An ATSDR health consultation is a verbal or written response from ATSDR to a specific
request for information about health risks related to a specific site, a chemical release, or
the presence of hazardous material. In order to prevent or mitigate exposures, a
consultation may lead to specific actions, such as restricting use of or replacing water
supplies; intensifying environmental sampling; restricting site access; or removing the
contaminated material.
In addition, consultations may recommend additional public health actions, such as
conducting health surveillance activities to evaluate exposure or trends in adverse health
outcomes; conducting biological indicators of exposure studies to assess exposure; and
providing health education for health care providers and community members. This
concludes the health consultation process for this site, unless additional information is
obtained by ATSDR which, in the Agency’s opinion, indicates a need to revise or append
the conclusions previously issued.
You May Contact ATSDR Toll Free at
1-800-CDC-INFO
or
Visit our Home Page at: http://www.atsdr.cdc.gov
HEALTH CONSULTATION
Exposure Investigation
Biological Testing for Exposure to Lead
FORMER UNITED ZINC & ASSOCIATED SMELTERS
IOLA, KANSAS
Prepared By:
U.S. Department of Health and Human Services
Agency for Toxic Substances and Disease Registry (ATSDR)
Division of Community Health Investigations
Table of Contents
Executive Summary ........................................................................................................................ 2
Background and Purpose of the Exposure Investigation ................................................................ 4
Environmental Sampling Data ................................................................................................. 4
Previous Blood Lead Testing ....................................................................................................... 5
Risk Factors for Lead Exposure in Iola ........................................................................................ 7
Agency Roles .................................................................................................................................. 7
Methods........................................................................................................................................... 9
Criteria for Participation ............................................................................................................. 9
Participant Recruitment .............................................................................................................. 9
Biologic Sample Collection and Analytic Procedures ............................................................... 12
Results ........................................................................................................................................... 12
Participants in the Exposure Investigation ............................................................................... 12
Blood Lead Results .................................................................................................................... 13
Lead and Health Effects ............................................................................................................ 17
Limitations of this Exposure Investigation ................................................................................ 20
Conclusions ................................................................................................................................... 20
Recommendations ......................................................................................................................... 21
Public Health Action Plan ............................................................................................................. 22
Actions Completed .................................................................................................................... 22
Actions Proposed ...................................................................................................................... 22
Authors.......................................................................................................................................... 24
Acknowledgements .................................................................................................................. 25
References ..................................................................................................................................... 26
Appendix A: Iola Exposure Investigation Map and Demographics ............................................. 29
.................................................................................................................................................. 29
Appendix B: Site Map and Soil Lead Levels in Iola, Kansas ....................................................... 30
Appendix D: PESHU Recommendations for Lead ...................................................................... 34
Recommendations on Medical Management of Childhood Lead Exposure and Poisoning......... 34
Figures
Figure 1. Blood Lead Levels by Age in Iola, Kansas
Figure 2. Comparison of Median BLL in Iola EI to NHANES
Tables
Table 1. EPA Operational Units (OUs) in Iola, KS
Table 2. Blood Testing Results In Iola, KS
Table 3. Exposure Investigation (EI) Activities and Agency Roles
Table 4: Goals, Recruitment Efforts and Results for the Iola EI
Table 5: Summary of Participants by Age and Gender
Table 6: Calculated Median Values and Confidence Intervals for Blood Lead Results, by Age
Abbreviations and Acronyms
ATSDR
BLL
CDC
DHHS
DLS
EI
EPA
KDHE
µg/dL
mg/kg
NCEH
NHANES
OMB
PEHSU
SEKMCHD
WIC
Agency for Toxic Substances and Disease Registry
blood lead level
Centers for Disease Control and Prevention
Department of Health and Human Services
Division of Laboratory Sciences
Exposure Investigation
(U.S.) Environmental Protection Agency
Kansas Department of Health and Environment
micrograms per deciliter
milligrams per kilogram
National Center for Environmental Health
National Health and Nutrition Examination Survey
Office of Management and Budget
Pediatric Environmental Health Specialty Unit
Southeast Kansas Multi-County Health Department
Women, Infants and Children Program
Executive Summary
The Agency for Toxic Substances and Disease Registry (ATSDR) conducted an Exposure
Investigation (EI) in Iola, Kansas with two sampling events in December 2016 and August 2017.
Iola is home to the Former United Zinc and Associated Smelters site, which is included on the
Superfund National Priority List (NPL). This hazardous waste site resulted from historical
smelting operations in Iola from 1902 to 1925. Residential and non-residential properties are
contaminated with elevated levels of lead in soil due to previous smelting operations. As a result,
there is potential for exposure to lead in the community. The U.S. Environmental Protection
Agency (EPA) is in the process of remediating the soil in Iola based on lead levels reported from
sampling conducted in 2006 and 2013.
At the request of EPA, the ATSDR EI team collected blood samples from participants living
within the city limits of Iola and analyzed the samples for lead. Children and women who were
pregnant or of childbearing age had their blood tested for lead. The most vulnerable populations
include young children with hand-to-mouth behavior and children with pica behaviors (i.e.,
craving to eat nonfood items, such as dirt, paint chips and clay). Pregnant women and women
who may become pregnant were also tested because of effects lead can have on a developing
fetus.
The Centers for Disease Control and Prevention (CDC) adopted a blood lead reference value of 5
micrograms per deciliter (µg/dL) in 2012 to identify children who require case management
[CDC 2012a]. There is no identified threshold or “safe” blood lead level, and some studies
indicate that even very low BLLs can cause neurological, cognitive, and attention-related
behavioral issues in children [CDC 2012b]. In this EI, ATSDR used 5 µg/dL as the investigation
follow-up level for lead for all ages, including children older than 6 years, pregnant women, and
women of childbearing age.
The EI was conducted in two sampling events, one in December 2016 and one in August 2017.
The December 2016 event offered blood lead testing to people living in homes with the highest
levels of lead in soil. Homes with soil lead greater than 800 milligrams per kilogram (mg/kg) that
had not been remediated by EPA were identified and residents were sent a letter inviting them to
participate. The EI team followed up the letter by visiting these homes to provide information
about the testing and to sign up participants. Although this group of residents were specifically
recruited for the testing, any eligible resident of Iola was welcome to be tested. In the December
testing event, 7 participants were tested (5 children and 2 women). None of the participants had
blood lead levels (BLL) greater than 5 µg/dL. All participants were notified of their results by
phone and were sent a letter that provided the results of the testing as well as recommendations
on how to reduce exposure to lead in soil both outside and inside the home.
For the August 2017 event, ATSDR completed a more comprehensive recruitment effort that
invited all eligible Iola residents to participate and raised awareness of lead issues in Iola.
Recruitment included sending an informational postcard to all homes with soil lead greater than
400 mg/kg followed by door-to-door recruitment at the homes. Outreach also included raising
awareness of lead issues in Iola by providing information on lead to local physicians, daycares,
and schools, and by hanging posters detailing the testing event at key locations around the
community. As with the December testing event, all eligible residents of Iola were welcome to
be tested. In the August event, 54 participants were tested: 36 children and 18 women. One child
younger than 6 years old had a BLL greater than 5 µg/dL. The parent was notified of the results
by phone and retesting was recommended. All participants were provided a letter with their
results that also outlined recommendations for reducing exposure to soil both inside and outside
the home.
The EI results in Iola indicated that the median BLL for children aged birth to 11 years were
approximately two to three times higher compared to what would be expected based on the
National Health and Nutrition Examination Survey (NHANES) data [birth to 5 years: 1.35 µg/dL
for Iola (0.74 µg/dL for NHANES); 6-11 years: 1.5 µg/dL for Iola (0.53 µg/dL for NHANES)] .
The BLL results for older children (12 to 19 years) and female adults tested in Iola were
comparable the NHANES data for those age groups. NHANES represents the median BLL for
people in the general U.S. population.
Residents of Iola have a higher potential for exposure to lead given elevated concentrations of
lead in soil: average of 333 mg/kg in Iola [EPA 2018] compared to 21 mg/kg lead for
background soil in Kansas [Smith et al. 2014]. In addition, the majority of homes in the
community were built prior to 1978, when lead was allowed in paint. An additional risk factor
for the Iola community is an elevated level of poverty (27% of residents below the poverty line)
[American Fact Finder 2018]. All participants tested had measurable lead in the blood (level of
detection = 0.07 µg/dL) and BLLs were higher in children as compared to adults. The EI results
indicating that children have higher blood lead than adults are consistent with the increased
absorption of lead by children compared to adults [Bearer 1995] and the higher potential for
children to have contact with contaminated soil and lead paint due to outside play and mouthing
activities in young children. The results of the questionnaire administered to participants
documented the amount of time that participants spent outside and mouthing activity of the
children.
The results of the EI are limited since they are only applicable to the individuals tested and
cannot be generalized. The results do not provide information to determine when the exposure
occurred or the specific source of exposure. Given the age of homes in Iola, lead in paint, indoor
air and drinking water may be significant contributors to potential lead exposure.
Recommendations
EPA is in the process of removing lead-contaminated soils in Iola and installing seed or sod to
provide grass cover in residential yards. ATSDR supports the remedial actions taken by EPA that
will result in lower exposure of the Iola community to lead. ATSDR recommends primary
prevention efforts to avoid exposure to lead in soil. Therefore, ATSDR supports the following
public health actions:
1. Try to prevent exposure to potentially contaminated soil outside the home during outdoor
activities.
2. Try to prevent exposure to potentially contaminated soil inside the home, e.g, tracking
soil into the home that becomes indoor dust.
3. Take additional measures to protect children younger than 6 years of age by ensuring that
painted surfaces are maintained to reduce exposure to lead paint and practicing good
hygiene to reduce exposure to soil and dust.
4. Educate health professionals about the impact on the community of past smelting
activities and the importance of reducing lead exposure and conducting appropriate lead
testing.
Background and Purpose of the Exposure Investigation
Iola is the county seat of Allen County and is located along the Neosho River in southeastern
Kansas. In the 2010 census, the population of Iola was 5,875 (Appendix A). Smelting operations
resulted in lead contamination of soil at both residential and commercial locations in Iola
(Appendix B). Lead exposure may also result from lead in house paint since the majority of the
homes in Iola (77%) were built before 1978, when lead was allowed in house paint (Appendix
A).
Environmental Sampling Data
The Kansas Department of Health and Environment (KDHE) was involved in sampling and
cleanup activities starting in the 1990’s. EPA began testing soil in Iola in 2005 at residential
homes, daycare facilities, schools, and commercial areas. Maximum concentrations of lead in
soil were 2,290 mg/kg in residential yards and 6,433 mg/kg at commercial properties. In 2015,
the mean level for lead in soil in Iola prior to remediation was 333 mg/kg (median 223 mg/kg)
[EPA 2015]. This value represents all samples taken by EPA in Iola from a database of soil data
using on-site XRF (X-ray fluorescence) and laboratory analysis. The data consist of 17,550 soil
lead results from 3,540 unique properties (residential, commercial, and vacant lots). The samples
were taken by separating the yards into quadrants and analyzing up to four samples per yard. In
addition, driplines (the location where rain runs off a roof onto the ground) were analyzed where
appropriate. The soil sampling data used to evaluate a potential correlation between BLL tested
for the EI and soil levels reflect the maximum soil concentration found at the home of the
participant.
EPA’s soil testing indicates that soil lead levels in Iola are well above the mean background level
of 21 mg/kg in Kansas [Smith et al. 2014]. Appendix B provides a historical map of the Iola area
and EPA results for lead in soil prior to remediation. Bioaccessibility studies for soil in Iola
indicate that the bioavailability of lead in soil and dust was estimated at 31% [EPA 2016].
EPA has divided the site into three categories called operable units (OUs). EPA often portions a
site into smaller units, or OUs, to assist in site management and ultimate cleanup at a site. The
criteria for the categorization into OUs are described in Table 1.
Table 1. EPA Operational Units (OUs) in Iola, KS
OU
Criteria
Remedial Action
OU-00
1. Residential properties with soil lead
greater than 800 mg/kg,
2. High Impact sensitive population
areas such as schools and daycares
where composite sample results
exceed 400 mg/kg,
3. Residential properties with soil lead
between 400 and 800 mg/kg where
a child with a BLL greater than 10
µg/dL resides. BLL from any
testing, including the EI, may be
used by EPA to identify these
residential locations.
479 properties identified to date
129 residential properties
remediated in 2005-2006
Two emergency removal actions
were completed at Iola schools in
2005 (maximum soil level of
5,500 mg/kg)
Approximately 250 residential
properties were remediated
between September 2015 and
August 2017.
Remainder will be scheduled for
remediation
OU-01
Residential properties with soil lead
between 400 and 800 mg/kg
763 properties identified to date
To be remediated after EPA
chooses a remedy (in progress as
part of the RI/FS process)
OU-02
Commercial properties
Lead in soil will be remediated in the
future using to-be-determined criteria
Previous Blood Lead Testing
Blood testing efforts in Iola from 2006 to 2012 are shown in Table 2. The blood testing in Iola
and Allen County from 2007 to 2012 indicate 14.1% (Iola) and 14.6% (Allen County) of
children tested during that period exceeded the current CDC’s reference level for children’s
blood lead (Table 2). It should be noted that, during that timeframe, the CDC reference level was
10 µg/dL and not the current 5 µg/dL. Similar exceedances of the reference level were reported
in 2011 and 2012 in Iola (14.6% and 13.8%) and Allen County (13.2% and 15.5%) (Table 2).
The State of Kansas has not had a CDC-funded child blood lead surveillance system in place
since 2012. The Southeast Kansas Multi-County Health District (SEKMCHD) performed limited
testing in association with the Women, Infants and Children (WIC) program from 2015 to 2016
and observed that 5.6% of the children tested under the program had blood lead levels in excess
of 5 μg/dL. The sharp difference in exceedance rates between these data sets gave rise to
concerns that the WIC dataset may reflect differences in collection methods or characteristics of
the tested population (e.g., age, gender, socioeconomic class).
Because high lead levels are present in the soil in Iola, the potential for human exposure to lead
exists. The most vulnerable populations to the health effects of lead exposure include young
children with hand-to-mouth behavior, children with pica behavior, pregnant women, and
women who may become pregnant. The latter two groups are a vulnerable population because of
leads effects on the developing fetus.
Table 2. Blood Lead Testing Results in Iola, KS
Year
20072010*†‡
2011*†‡
2012*†‡
2015-2016§
Location
Total
number
tested
(<6 yrs old)
BLL results in children
(number of children)
%≥
5 µg/dL**
Allen County
total
Iola
Rest of
Allen
County
Allen County
total
Iola
574
5 to <10 µg/dL
64
≥10 µg/dL
20
14.6%
391
183
43
21
12
8
14.1%
15.8%
144
14
5
13.2%
96
11
3
14.6%
Rest of
Allen
County
48
3
2
10.4%
Allen County
total
Iola
Rest of
Allen
County
181
24
4
15.5%
116
65
13
11
3
1
13.8%
18.5%
Iola (WIC)
160
9
0
5.6%
* [KDHE 2018] Kansas Department of Health and Environment. 2018. Personal communication between Farah
Ahmed and Spencer Williams, ATSDR, February 1, 2018.
†
The number sampled for Allen County includes the number for Iola plus the number for the rest of Allen
County. The numbers reflect individual children and do not include followup testing, if completed.
‡
Statistics for the data from KDHE and SEKMCHD for Allen County and Iola include capillary samples >5
μg/dL that were not later tested by venous sample. Of 21 capillary samples from Iola children subjected to
confirmation by venous sampling from 2007-2010, only 2 were found to not represent an elevated blood lead
level finding. All elevated blood lead level findings subjected to venous sampling in 2011 and 2012 were
confirmed. Statistics for 2007-2010 treat children tested in different years as independent samples.
§
[SEKMCHD 2016] 2016. Southeast Kansas Multi-County Health Department. Personal communication
between Chardel Hastings and Spencer Williams, ATSDR, October 17, 2016.
** The value of 5 µg/dL was selected because it is the CDC reference level based on the 97.5% BLL for
children 1 to 5 years of age.
Abbreviations: KS = Kansas; BLL = Blood Lead Level; WIC = Women, Infants and Children; µg/dL =
micrograms of lead per deciliter of blood
Risk Factors for Lead Exposure in Iola
In addition to the potential exposure to contaminated soil, people living in the area have multiple
factors associated with increased risk of lead exposure. The census tract has a large percentage of
homes built before 1978 (77%) that may have lead-based paint and lead pipes that may impact
drinking water [U.S. Census Bureau 2010] (Appendix A). In addition, approximately 27% of
residents in Iola were below the poverty line in 2015 [American Fact Finder 2018] (Appendix
A). Poverty is an additional risk factor for increased BLL [Dixon et al. 2009, Jones et al. 2009,
Bernard et al. 2003].
Agency Roles
A number of activities are conducted during an EI. ATSDR, the lead agency for the EI,
collaborated with EPA, the KDHE, the SEKMCHD, and the CDC National Center for
Environmental Health (NCEH) Division of Laboratory Sciences (DLS) to complete these
activities. The roles of each agency are described in Table 3.
Table 3. Exposure Investigation Activities and Agency Roles
Activity
EI protocol and
PRA/OMB submittal
Agency
ATSDR
Agency Role
Completed the EI protocol which included Fact
Sheets, Flyers, Posters, Questionnaire, Parental
Permission, Consent and Assent Forms,
Sampling and Analysis Plan
Submitted the Paperwork Reduction Act (PRA)
forms to the Office of Management and Budget
(OMB) for approval to administer the
questionnaire and consent forms. This package
also included an Institutional Review Board
(IRB) exemption since the EI is not considered
to be research.
Identification of
properties based on
soil lead levels
EPA
Provided information regarding soil lead levels
and the status of remediation at residential
homes in Iola in order to identify a mailing list
for recruitment materials.
Provided ATSDR
with BLL for children
in Iola
KDHE and
SEKMCHD
Participant
recruitment
ATSDR, EPA
Blood sample
collection
ATSDR
December 2016: identified homes with ≥ 800
mg/kg in soil that had not been remediated.
August 2017: identified all homes with ≥ 400
mg/kg in soil.
Both state agencies provided ATSDR with BLL
data for children in Iola. The agencies will
continue to engage the community regarding
potential lead contamination in Iola.
Conducted door-to-door recruiting and
scheduled appointments.
Administered parental permission/assent/consent
forms to participants and their parent/guardian.
Hired licensed phlebotomists to draw blood from
participants.
Blood sample
analysis
NCEH/DLS
Used approved laboratory methods to analyze
biological samples for lead and provide results to
ATSDR.
Table 3. Exposure Investigation Activities and Agency Roles
Activity
Reporting of results
Agency
ATSDR
Agency Role
Prepared and mailed letters with results to all
participants.
Contacted the participants in the EI who had
BLL greater than 5 µg/dL to recommend
followup with their physician.
Evaluated data and prepared the Exposure
Investigation (EI) report.
Abbreviations: ATSDR, Agency for Toxic Substances and Disease Registry; EPA, Environmental Protection
Agency; KDHE, Kansas Department of Health and Environment; SEKMCHD, Southeast Kansas Multi-County
Health Department; NCEH/DLS, National Center for Environmental Health/Division of Laboratory Services
Methods
The methods used to identify and recruit participants, collect blood samples, and perform
laboratory analyses are provided below.
Criteria for Participation
Participants were recruited in Iola for the EI based on the following criteria:
Children younger than 6 years of age
Women who are pregnant or of childbearing age
Siblings of children younger than 6 years of age at the parent’s request
In Iola in 2010, there were 489 children 6 years of age and younger and 1,140 females of
childbearing age (aged 15-44 years) [U.S. Census Bureau 2010] (Appendix A).
Participant Recruitment
Residents that met the above criteria were recruited for the two phases of the EI as follows:
December 2016: ATSDR recruited eligible people living at residences with yard soil lead
≥ 800 mg/kg (identified by EPA) that had not been remediated to offer blood lead testing.
The residents in these homes are potentially the most highly exposed persons in the
community.
August 2017: ATSDR recruited all eligible people living in Iola for testing and provided
a comprehensive outreach program to educate the community about the potential health
impacts of lead in soil in Iola.
The goals of the EI, the recruitment efforts, and the results for each phase of the EI are presented
in Table 4:
Table 4: Goals, Recruitment Efforts and Results for the Iola EI
Testing Date
December 2016
August 2017
Goal
Test eligible children/women in Iola homes
with the highest levels of lead in soil (≥ 800
mg/kg). The goal was to provide immediate
BLL testing for those residents with the
highest potential for exposure and to provide
follow-up as needed.
Test eligible children/women in Iola homes.
In addition, provide all Iola residents with
education and awareness of lead issues in the
community
Recruitment Effort
Invited all Iola residents that met the
recruitment criteria to be tested for
BLL
Mailed 216 recruitment letters and fact
sheets to addresses with ≥ 800 mg/kg
lead in soil that had not been
remediated. Approximately 37% of
the letters were returned as
undeliverable.
Went door to door to each of the
homes that received recruitment
letters, even if they were returned, to
provide information on the testing and
make appointments for testing.
Invited all Iola residents that met the
recruitment criteria to be tested for
BLL
Provided information to the
community on the testing event,
including how to sign up, using
numerous methods
Mailed 987 recruitment postcards to
homes with ≥ 400 mg/kg lead in soil,
including those that received the
letter/fact sheet for the December
event. Approximately 30% of the
postcards were returned as
undeliverable.
Went door to door to each of the
homes that received postcards, even if
they were returned, to recruit
participants and make appointments
for testing
Provided information packets for lead
and testing information to local
physicians
Visited daycares/schools, and
religious and community
organizations in Iola and provided fact
sheets and recruitment materials
Table 4: Goals, Recruitment Efforts and Results for the Iola EI
Testing Date
December 2016
August 2017
Visited local government offices to
make them aware of testing and
provide them with fact sheets
Placed posters throughout the city in
public locations to make community
aware of testing effort
Staffed a booth at the county fair the
weekend of recruitment providing
information to fair goers
Attended the city farmer’s market to
hand out informational and recruiting
materials to citizens
Filmed a public service spot on
SeeHearIola – a local television
channel in Iola
Announced the testing in a press
release in local Iola newspaper
Results
12 appointments made for testing
7 participants tested
o 5 children (birth to 19 years)
o 2 women (20 years and older)
Approximately 100 appointments
made for testing
54 participants tested*
o 36 children (birth to 19 years)
o 18 women (20 years and older)
* - Ten participants (6 children younger than 6 years old and 4 women of childbearing age) that lived outside of Iola
were included because they reported frequent contact with the contaminated soil in Iola while visiting family. One
family recently moved outside of Iola and requested testing because they resided in Iola for many years.
Abbreviations: EI = Exposure Investigation; BLL = Blood Lead Level
Given the goals of the two EI events, information sharing and recruitment efforts for the August
2017 event were much more extensive than the December 2016 effort. Although the recruitment
effort was extensive in August 2017, it did not result in a large number of participants. The
recruitment effort, however, resulted in a greater awareness of lead issues within the community
and in the surrounding area. Area physicians were provided information regarding potential
effects of lead in young children and pregnant women and were encouraged to share information
with their patients and recommend BLL testing. Several families that live outside Iola but spend
time in Iola (e.g., at grandparents homes, etc.) requested testing as a result of the increased
awareness of lead issues in the Iola area during the recruitment process. These participants were
included in the EI since they had exposure to lead in soil in Iola.
Biologic Sample Collection and Analytic Procedures
ATSDR administered Consent/Assent/Parental Permission forms prior to collecting the blood
samples. Blood samples were collected on December 12, 2016 and from August 3-6, 2017.
ATSDR team members collected pertinent information from the head of each household using an
Office of Management and Budget (OMB) approved questionnaire (OMB # 0923-0048). The
household questionnaire included questions on demographics, characteristics and age of
residence, and activities that might result in exposure to lead. Federal rules require that ATSDR
maintain confidentiality of the information gathered through interviews as well as the results of
laboratory tests. An adult from each household completed a questionnaire to assess potential
exposures to lead resulting from daily activities.
Blood lead sampling is the most reliable method for measuring lead exposure from all sources
[Barbosa et al. 2005]. Whole blood samples were obtained by venous puncture. A phlebotomist
(medical professional who draws blood from a vein) collected 3 milliliters (ml) of blood from
each participant who provided consent. The collection tubes and supplies were provided by the
NCEH/DLS. To maintain privacy, the samples were labeled with a unique identification number.
After collection, blood samples were maintained near 4ºC throughout the week and during
overnight shipment. Samples were delivered for analysis to the NCEH/DLS laboratory in
Atlanta, Georgia.
The NCEH/DLS laboratory performed blood lead testing in Atlanta, Georgia using NHANES
Method 2009-2010 [CDC 2009-2010] and Quality Assurance/Quality Control for lead according
to NHANES 2007-2008 [CDC 2007-2008a,b].
All participants in the EI were sent a letter that contained their BLL results and provided
information on how to reduce lead exposure both inside and outside the home.
Results
Participants in the Exposure Investigation
Sixty-one people participated in the EI: 7 people in December 2016 and 54 people in August
2017 (Table 5). Adults evaluated in the Iola EI were women 20 years of age or older. The
participants by age and gender are reported in Table 5.
Table 5. Summary of Participants by Age and Gender
Age Group
Birth to 5 years old
6 to 11 years old
12 to 19 years old
≥ 20 years old
Total number of participants with Blood Lead Testing
(n=61)
Males
Females
Total
15*
8
3
0
9*
4
2
20†
24
12
5
20
* 4 males and 2 females in this age range were from outside Iola city limits
†
4 women were from outside Iola city limits
Based on the questionnaire responses, 73% (30/41) of the child participants (aged birth to 19
years) and 100% (20/20) of the adults are non-Hispanic and identify as white. The remaining
children identified as mixed race (11/41 = 27%) including white/black, white/Hispanic or
white/native American. The majority of the participants lived in single-family homes that were
older than 1978, the year that lead-based paint was no longer manufactured. Eighty percent of
the families had lived in their homes 5 years or less. Participants were asked how often they and
their children took their shoes off before entering their home, how often they washed their hands
and cleaned their homes, and if their children exhibited mouthing or pica behavior (e.g., eating
dirt). Pica behavior was reported by the parents in approximately 23% of the children, including
the child that had the elevated BLL. They were also asked whether they regularly use items that
may contain lead, such as Mexican pottery or candy or home remedies that may contain lead.
Studies have reported that blood lead levels may be elevated when indoor dust contains elevated
levels of lead resulting from lead based paint and the tracking of lead-containing soil into the
home [Dixon et al. 2009]. Indoor dust samples were not available for households in Iola so it was
not known what contribution lead in indoor dust, if any, would have on BLL in Iola residents.
Blood Lead Results
In 2012, CDC adopted the 97.5 percentile of the NHANES as a blood lead reference level; the
current level is 5 µg/dL. This level is based on the U.S. population of children ages 1-5 years
with BLLs in the highest 2.5% who require case management [CDC 2012a,b,c]. For this
investigation, ATSDR used 5 µg/dL of blood lead as the investigation level to identify
participants for follow-up (including children, pregnant women, and women who may become
pregnant).
One child younger than 6 years old had a BLL (6.3 µg/dL) that exceeded the investigation
follow-up level of 5 µg/dL. The child with the BLL above the reference level was reported to
play in the yard up to 6 hours per day and has exhibited pica behavior. ATSDR contacted the
family by phone and recommended that the child receive follow-up blood lead testing.
Figure 1 provides the results of the blood lead testing in Iola in December 2016 and August
2017. It also includes participants that were located outside of the Iola city limits, but were
included because they spend a lot of time in Iola and are likely exposed to contaminated soil.
Higher BLLs were observed in children as compared to adults (Figure 1). In August 2017, one
child had a BLL that exceeded the investigation follow-up level of 5 µg/dL; no adults had BLLs
greater than 5 µg/dL. Results were comparable between the December 2016 and August 2017 testing
events and between residents living within the Iola city limits and those that resided outside Iola but
were exposed to soil in Iola. In the state of Kansas, a BLL of 10 µg/dL or greater is reportable to
the state health department, therefore, no BLL for EI participants were reportable.
Figure 1
Blood Lead Levels by Age in the Iola, Kansas EI
Figure 2 and Table 6 provide the median BLL found in the Iola EI for various age groups (birth
to 5 years, 6 to 11 years, 12 to 19 years and 20 to 47 years) compared to the median BLL for the
U.S. population (NHANES) [CDC 2017]. For children up to age 19, the NHANES values are
provided for both males and females, and a female-only comparison was completed for women
of childbearing age older than 20 years old. The U.S. population (NHANES) results are provided
here primarily for context; comparisons between the EI participant results and U.S. population
(NHANES) results should be interpreted with caution for a number of reasons. The small sample
size (number of people) and demographic bias (children and female adults of child-bearing age
were preferentially recruited) of the EI participant group make statistical comparisons between
the EI results and the U.S. population inappropriate.
Figure 2
Comparison of Median BLL in Iola EI to NHANES
Table 6: Median Values and Confidence Intervals for Blood Lead Results, by Age
Age Group
Gender
Median BLL and 95%
confidence interval for
ATSDR EI results*
µg/dL
birth to 5 years
6-11 years
12-19 years
20 to 47 years
Male and female
Male and female
Male and female
Female only
1.35 (0.5–1.83)†
1.5 (0.49-2.20)†
0.67 (0.00-1.98)
0.64 (0.40-0.81)
Median BLL and 95%
confidence interval for
corresponding NHANES
results, in µg/dL
0.74 (0.68-0.80)
0.53 (0.50-0.57)
0.46 (0.42-0.50)
0.81 (0.78-0.85)
*Confidence intervals for the EI data are calculated using bootstrap methods, n=2,000, with replacement.
†
These median values are above the corresponding U.S. population (NHANES) value, however the EI has a
number of inherent limitations that make comparison difficult (e.g. the EI sample size is small, there are
methodological and demographic differences between the EI and U.S. population results). The U.S. population
results should be used primarily for context.
Abbreviations: BLL = blood lead level; BLL = Blood Lead Level; ATSDR = Agency for Toxic Substances and
Disease Registry; EI = Exposure Investigation; NHANES = National Health and Nutrition Survey (CDC 20132014 data); µg/dL = micrograms of lead per deciliter of blood.
An analysis comparing the soil lead levels in the yards of the participants (EPA data) and their
BLL reported in this EI is provided in Appendix C. For all ages and for selected individual age
groups, the relationship between BLL and measured lead in soil is statistically significant but the
effect levels are fairly low. In other words, it takes a big increase in lead in soil (1,000 mg/kg) to
produce a small increase in BLL (0.4 +/- 0.15 µg/dL). It should be noted that because of the
small sample sizes, a few very high soil lead and BLL results strongly influenced the outcome of
the analysis.
The low effect levels between BLL and measured lead in soil could be interpreted as reinforcing
the concept that there could be many different sources and pathways of exposure to lead in the
environment at the site, e.g., lead in tap water or indoor dust resulting from lead in soil and lead
paint in the home.
Lead and Health Effects
Lead is a naturally occurring metal. Typically found at low levels in soil, lead is processed for
many industrial and manufacturing applications, and it is found in many metallic alloys. Lead
was banned as an additive to gasoline in 1996 and from paint in 1978. Lead can be found in all
parts of our environment because of past and current human activities including burning fossil
fuels, mining, and manufacturing processes [ATSDR 2007]. Because of this, lead is often found
in the body at low levels. Lead exposure occurs primarily via the oral route, with some
contribution from the inhalation route. The toxic effects of lead are the same regardless of the
route of entry into the body.
Lead has no physiological value, and if it gets into the blood, lead can affect various organ
systems and be stored in the bones. Lead that is not stored in bones and teeth is excreted from the
body in urine and feces. About 99% of the amount of lead taken into the body of an adult will
leave the body in urine or feces within a couple of weeks, while about 30% of the lead taken into
the body of a child will leave the body in urine or feces [ATSDR 2007]. Lead can stay in bones
for decades. Lead can leave bones and re-enter the blood and deposit in organs under certain
circumstances: during pregnancy and lactation, after a bone is broken, and during menopause in
women due to osteoporosis [ATSDR 2007].
An elevated level of lead in a person’s blood is an indication that an exposure has occurred. In
general, BLL correlates well with adverse health effects [ATSDR 2007].
Depending on the level of exposure, lead can adversely affect the nervous system, kidney
function, immune system, reproductive system, cardiovascular system and development. Lead
exposure also affects the oxygen carrying capacity of the blood. The lead effects most commonly
encountered are neurological effects in children, and cardiovascular effects (e.g., high blood
pressure and heart disease) in adults.
The primary impacts of lead are found on infants and the fetus, therefore, this EI focused
primarily on the testing of children younger than 6 years old and women who were pregnant or
of childbearing age. The emphasis on pregnant women and children younger than 6 years is
because epidemiologic cohort studies suggest that prenatal lead exposure, even with maternal
BLLs <10 µg/dL, is inversely related to fetal growth and neurodevelopment independent of the
effects of postnatal lead exposure. Lead exposure can also cause a miscarriage. Infants and
young children are especially sensitive to even low levels of lead, which may contribute to
behavioral problems, learning deficits, and lowered IQ (intelligence quotient) [Lanphear et al.
2005, Crump et al. 2013, EPA 2013]. The exact mechanism(s) by which low-level lead exposure,
whether incurred prenatally or postnatally, may adversely affect child development remains
uncertain [DHHS, 2010].
No acceptable BLL has been identified that is free from deleterious health effects in children
from 1 to 5 years of age and [CDC 2012a,b,c]. This value is the 97.5 percentile for the
distribution of blood lead levels of U.S. children 1 – 5 years old [CDC 2012 a,b,c]. Studies
conducted in pregnant women, developing fetuses, children and adults substantiate there is
sufficient evidence of health effects at BLL <5 µg/dL [Lanphear et al. 2005, Crump et al. 2013].
In Kansas, the reportable blood lead level is ≥10 µg/dL for children.
BLL should be kept as low as possible and below the level of 5 ug/dL since no safe blood lead
level in children has been identified. Young children and the developing fetus are particularly
sensitive to the effects of lead. The Pediatric Environmental Health Specialty Units (PEHSU)
provide recommendations for medical management of children exposed to lead at all BLLs
(Appendix D). CDC also provides a guide for recommended actions based on BLL
(https://www.cdc.gov/nceh/lead/acclpp/actions_blls.html).
In 2015, the National Institute for Occupational Safety and Health (NIOSH) and the
Occupational Safety and Health Administration (OSHA) also recommended that BLLs in adults
should be <5 µg/dL. (http://www.cdc.gov/niosh/topics/ables/description.html). Therefore, the
value of 5 µg/dL was used as a reference level for the women of childbearing age tested in this
EI.
It is not known for certain if lead causes cancer in humans. Rats and mice fed large amounts of
lead in their food developed kidney tumors. The U.S. Department of Health and Human Services
classifies lead as “reasonably anticipated” to cause cancer and EPA considers lead a “probable”
cancer causing substance [ATSDR 2007]. Because of the absence of any clear threshold for
some of lead’s more sensitive health effects [EPA 2013], ATSDR has not established guidelines
for a low or no risk lead intake dose.
Some characteristics contribute to susceptibility (e.g., age, race, sex) and others to vulnerability
(e.g., socio-economic status and living in older housing). Living in older housing [CDC 2013,
Bernard et al. 2003], and poverty [CDC 2013, Jones et al. 2009] and being non-Hispanic black
[Bernard et al. 2003, CDC 2013, Jones et al. 2009] are risk factors for higher blood lead levels.
In 2010, the population in the census track of Iola (Appendix A) was predominantly white (over
90%) [U.S. Census 2010]. The age of the homes and the high percentage of poverty in Iola
increases the likelihood for higher BLLs in the community. The majority of the homes (77%)
were built prior to 1978 and may contain lead paint since lead paint was sold prior to 1978.
Approximately 90% of participants reported that their homes were built prior to 1978.
Approximately 27% of the Iola community were below the poverty level in 2015 [American Fact
Finder 2018].
In this exposure investigation, the BLL in one child younger than 6 years was greater than 5
µg/dL (6.3 µg/dL). Levels such as these can adversely affect the child’s health [NTP 2012]. The
child with the BLL greater than 5 ug/dL exhibited pica behavior (i.e., eating dirt) and lived in a
home built in the 1970s, indicating it may contain lead-based paint. The BLL for all women of
childbearing age were below 5 µg/dL.
BLLs in EI participants were higher in children as compared to adults. The median BLL for EI
participants were higher than the median BLL for the U.S. population for children (aged birth to
11 years) but not for adults (Table 6 and Figure 2). The higher BLLs in children indicate that
behavior in children (e.g., hand to mouth activity, playing in dirt) likely results in higher
exposure to contaminants, including lead, in soil. Lead gastrointestinal absorption in children is
also many times higher than in adults [ATSDR 2007].
Limitations of this Exposure Investigation
All investigations have some inherent limitations. This EI has the following limitations:
The results of this EI are applicable only to the individuals tested and cannot be
generalized to other populations.
ATSDR conducted blood lead testing for a small fraction of the eligible population. This
sample size may not yield results representative of the area population.
Comparisons between the participant age groups and corresponding U.S. population age
groups should be interpreted with caution due to a number of methodological (sample
design) and demographic (gender and age) differences between the EI participant and
U.S. population groups.
ATSDR used bootstrap methods (n = 2,000 repetitions, with replacement) to calculate the
confidence intervals for the median blood lead levels; for small sample sizes (the
relatively small number of people in each age group), this method produces narrow
confidence intervals.
The results cannot be used to predict the future occurrence of disease in individuals.
Elevated blood lead indicates there was exposure to lead. However, results do not provide
information to determine when the exposure occurred.
Conclusions
ATSDR found that young children living in Iola are at increased risk of lead exposure from soil
and had elevated BLLs as compared to the background NHANES data; this exposure can harm
children’s health.
One child had a BLL greater than 5 µg/dL and five children had BLL between 3.5 and 4.1
µg/dL. No safe BLL in children has been identified, and even low lead levels can have adverse
health effects. Median (i.e., 50th percentile) blood lead levels for the youngest age groups (birth
to 5 years and 6 to 11 years) are higher than corresponding national averages.
In addition to the potential exposure to contaminated soil, people living in the area have factors
associated with increased risk of higher blood lead levels. The census tract showed
approximately 27% of Iola residents living in poverty in 2015 and a high percentage of homes
built before 1978 (77%), which may have lead-based paint (Appendix A). Studies have indicated
that these are all risk factors for higher BLLs [Dixon et al. 2009, Jones et al. 2009, Bernard et al.
2003].
Recommendations
ATSDR recommends primary prevention efforts to avoid exposure to lead wherever possible.
Therefore, ATSDR supports the following public health actions:
1. Take the following actions to prevent exposure to potentially contaminated soil outside
the home:
Cover bare soil with vegetation (grass, mulch, etc.)
Create safe play areas for children with appropriate and clean ground
covers. Consider sand boxes for children that like to dig.
Supervise children closely to modify or eliminate hand-to-mouth behavior
or intentional eating of dirt (pica behavior).
Keep children’s hands clean, wash frequently, especially before eating. Do
not eat food or chew gum when playing or working in the yard.
2. Take the following actions to prevent exposure to potentially contaminated soil inside
the home:
Remove shoes before going in the house to prevent tracking of
contaminated soil into the house.
Regularly conduct damp mopping and damp dusting of surfaces. Dry
sweeping and dusting could increase the amount of lead-contaminated
dust in the air.
Change and launder any dirty clothes separately after playing or working
outside.
Frequently bathe your pets as they could also track contaminated soil into
your home.
3. Take additional measures to protect children younger than 6 years of age:
Ensure that painted surfaces in the home are maintained and do not have
peeling paint so children will not be exposed to lead in paint chips. Homes
built before 1978 may contain lead paint.
Supervise children closely to prevent children from eating large amounts
of dirt (i.e., pica behavior).
Practice good hygiene with frequent hand washing, especially before
meals.
Wash children’s bottles, pacifiers, and toys frequently.
Offer nutritious age-appropriate meals rich in calcium, iron and vitamin C.
Children who eat healthy diets absorb less lead.
Have eligible children evaluated in the Women, Infant and Children
(WIC) program for blood lead.
4. Educate health professionals about the following:
Impact of past smelting activities on levels of lead in soil in Iola.
Prevention or reduction of lead exposure from soil and other sources, such
as lead-based paint.
Importance of conducting blood lead screening and confirmatory venous
blood lead testing.
ATSDR has a Case Studies in Environmental Medicine (CSEM) for lead
that provides a self-instructional primer designed to increase primary
health care providers knowledge of lead to aid in patient treatment.
https://www.atsdr.cdc.gov/csem/csem.asp?csem=34&po=0
Public Health Action Plan
The Public Health Action Plan for Iola contains a description of actions completed and proposed
actions by ATSDR and EPA. The purpose of the EI is to ensure that we identify exposures that
may be of public health concern and also provide a plan of action designed to prevent or mitigate
adverse human health effects from contaminant exposure. ATSDR will follow-up on this plan to
ensure these actions are carried out.
Actions Completed
1. In December 2016, ATSDR sent each participant a letter informing them of their BLL
results and called every participating household to discuss their own or their child’s
results.
2. In September 2017, ATSDR sent each participant a letter informing them of their BLL
results and called the household with the child that had an elevated BLL.
3.
Educational materials containing information regarding impacts of lead on young
children and pregnant women were provided to physicians in the area to assist with
patient management.
4. EPA continues to remediate yard soil per their remediation plan.
Actions Proposed
1. ATSDR will conduct a public availability session after this report is released to provide
information to the public regarding how to reduce exposure to lead in soil.
2. ATSDR will be available to community leaders and physicians in Iola to continue to
provide information and recommendations regarding how to reduce exposure to lead in
Iola.
Authors
Karen Scruton, MS
Environmental Health Scientist
Science Support Branch (SSB)
Division of Community Health Investigations (DCHI)
Data Analysis and Exposure Investigation Team
Cory Kokko, MPH
Regional Representative
Region 7 ATSDR
Division of Community Health Investigations (DCHI)
E. Spencer Williams, PhD, DABT
Former Regional Director and Toxicologist (no longer with ATSDR)
Region 7 ATSDR
Division of Community Health Investigations (DCHI)
Barbara Anderson, PE, MSEnvE
Science Support Branch
Division of Community Health Investigations (DCHI)
Data Analysis and Exposure Investigation Team
Acknowledgements
ATSDR is appreciative of the ATSDR personnel who were involved in recruitment, sampling
and data analysis for the EI, including Aaron Grober, Erin Evans, Bradley Goodwin, Charlie
Grosse, Katie Pugh, Dr. Bruce Tierney, Dr. Lourdes Rosales-Guevara, Christopher Poulet,
Barbara Anderson and Rene Suarez-Soto. ATSDR also appreciates the Environmental Protection
Agency’s (EPA) assistance with the Exposure Investigation (EI), including Don Bahnke,
Melinda Luetke, Randy Schademann, Tamara Freeman, Pamela Houston, and Elizabeth Kramer.
ATSDR would also like to thank the Dr. Jennifer Lowry of the Mid-America PEHSU, Jennifer
Carpenter, Laboratory Director of the Allen Regional Hospital, and Kathleen Caldwell and Sina
De Leon from the Division of Laboratory Services (DLS) at the National Center for
Environmental Health (NCEH).
Finally, ATSDR wants to thank the community, for its participation and collaboration on this EI.
In particular, ATSDR offers its gratitude to Sid Fleming, Iola’s City Administrator, Scott
Stanley, Director of Operations for Iola’s Unified School District (257) and Judy Baker, Iola
High School Administrative Secretary.
References
American Fact Finder, online, 2018. Percent of Related Children Under 18 Years Below Poverty
Level in the Past 12 Months.
https://factfinder.census.gov/faces/nav/jsf/pages/community_facts.xhtml
[ATSDR 2007] Agency for Toxic Substances and Disease Registry. 2007. Toxicological profile
for lead (update). Atlanta: US Department of Health and Human Services; 2007.
Barbosa F, et al. 2005. A critical review of biomarkers used for monitoring human exposure to
lead: Advantages, limitations and future needs. Environmental Health Perspective, 2005,
113:1669-1674.
Bearer CF. 1995. How Are children Different from Adults?. Environmental Health Perspectives.
103 (Suppl 6): 7-12. 1995.
Bernard SM, McGeeing MA, Michael A.2003. Prevalence of Blood Lead Levels greater than 5
µg/dL Among U.S. Children 1 to 5 Years of Age and Socioeconomic and Demographic
Factors associated with Blood Lead Levels 5 to 10 µg/dL, Third National Health and
Nutrition Examination Survey, 1988 – 1994. Pediatrics 2003;112;1308.
[CDC 2007-2008a] Centers for Disease Control and Prevention. National Health and Nutrition
Examination Survey. 2007-2008a. [DLS method 1003.1] Available online at:
http://www.cdc.gov/nchs/data/nhanes/nhanes_07_08/ALB_CR_e_met_urinary_creatinine
_CX3.pdf
[CDC 2007-2008b] Centers for Disease Control and Prevention. National Health and Nutrition
Examination Survey 2007-2008b. Statist. Med. 2008; 27:4094–4106. Analysis of NIST
(National Institute of Standards Technology)
[CDC 2009-2010] Centers for Disease Control and Prevention. National Health and Nutrition
Examination Survey 2009-2010. Blood Lead Cadmium Mercury ICPDRCMS. Method
No: 3001.1 http://www.cdc.gov/nchs/data/nhanes/nhanes_09_10/pbcd_f_met.pdf
[CDC 2012a] Centers for Disease Control and Prevention. Lead (web page). 2012a. Update on
Blood Lead Levels in Children. Last Updated October 30, 2012. Available online at:
http://www.cdc.gov/nceh/lead/ACCLPP/blood_lead_levels.htm
[CDC 2012b] Centers for Disease Control and Prevention. 2012b. Low Level Lead Exposure
Harms Children: A Renewed Call for Primary Prevention: Report of the Advisory
Committee on Childhood Lead Poisoning Prevention, Centers for Disease Control and
Prevention. U.S. Department of Health and Human Services, January. Available
at: http://www.cdc.gov/nceh/lead/acclpp/final_document_010412.pdf
[CDC 2012c] Centers for Disease Control and Prevention. 2012c. CDC Response to Advisory
Committee on Childhood Lead Poisoning Prevention Recommendations in "Low Level
Lead Exposure Harms Children: A Renewed Call of Primary Prevention". Centers for
Disease Control and Prevention, June 7, 2012. Available at:
http://www.cdc.gov/nceh/lead/ACCLPP/CDC_Response_Lead_Exposure_Recs.pdf
[CDC 2013] Centers for Diseases Control and Prevention. Blood Lead Levels in Children 1-5
Years-U.S. 1999-2010 (April 5, 2013) MMWR: Morbidity and mortality Weekly Report,
62913);245-248. Available at: http://www.cdc.gov/immigrantrefugeehealth/pdf/leadguidelines.pdf
[CDC 2017] Centers for Disease Control and Prevention. Fourth Report on Human Exposure
to Environmental Chemicals, Updated Tables, (January 2017). Atlanta, GA: U.S.
Department of Health and Human Services, Centers for Disease Control and
Prevention. https://www.cdc.gov/exposurereport/
Crump KS, Van Landingham C, et al., 2013. A statistical reevaluation of the data used in the
Lanphear et al. (2005) pooled-analysis that related low levels of blood lead to intellectual
deficits in children. Crit Rev Toxicol 43:785-799.
Dixon SL, Gaitens JM, et al., 2009. Exposure of U.S. Children to Residential Dust Lead, 19992004: II. The contribution of lead contaminated dust to children’s blood lead levels.
Environmental Health Perspective 117:468-474. Available at:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2661919/
[EPA 2013] U.S. Environmental Protection Agency. 2013. Integrated Science Assessment (ISA)
for Lead (Final Report, Jul 2013). U.S. Environmental Protection Agency, Washington,
DC, EPA/600/R-10/075F, 2013. https://www.epa.gov/isa/integrated-science-assessmentisa-lead
[EPA 2015] U.S. Environmental Protection Agency. 2015. Data set provided to ATSDR Region
7 from EPA for XRF (X-ray Fluorescence) and ICP-MS (Inductively Coupled Plasma
Magnetic Spectrometry) data for Iola soil.
[EPA 2016] U.S. Environmental Protection Agency. 2016. Memorandum: Concurrence with
Proposed Plan for Former United Zinc and Associated Smelters, Operable Unit 01, Allen
County, Kansas. https://semspub.epa.gov/work/07/30286126.pdf
[EPA 2018] U.S. Environmental Protection Agency. 2018. Direct communication between
Spencer Williams, ATSDR and EPA Region 7 personnel. March to May 2018.
Jones R, Homa D, Meyer P, et al. 2009. Trends in Blood Lead Levels and Blood Lead Testing
Among U.S. Children aged 1- 5 Years, 1988-2004. Pediatrics 2009. Mar; 123(3):e376385 Available at: http://pediatrics.aappublications.org/content/123/3/e376.full.pdf+html
[KDHE 2018] Kansas Department of Health and Environment. 2018. Personal communication
between Farah Ahmed and Spencer Williams, ATSDR, February 1, 2018.
Lanphear, BP, Hornung, R et al. 2005. Low-level environmental lead exposure and children’s
intellectual function: An international pooled analysis. Environ Health Perspect 113:894899.
[NTP 2012] National Toxicology Program. Health Effects of Low-Level Lead. U.S. Department
of Health and Human Services, June 2012.
[SEKMCHD 2016] 2016. Southeast Kansas Multi-County Health Department. Personal
communication between Chardel Hastings and Spencer Williams, ATSDR, October 17,
2016.
Smith, D.B., Cannon, et al., 2014. Geochemical and mineralogical maps for soils of the
conterminous United States: U.S. Geological Survey Open-File Report 2014–1082, 386
p., https://dx.doi.org/10.3133/ofr20141082.
U.S. Census Bureau. American Community Survey, 2010. American Community Survey.
Available at: http://www.census.gov/acs/www/
Appendix A: Iola Exposure Investigation Map and Demographics
Appendix B: Site Map and Soil Lead Levels in Iola, Kansas
Appendix C: Blood Lead Levels in Iola compared to Lead Soil Levels
ATSDR conducted several analyses of the relationship between measured lead in soil in
residential yards and measured blood lead level (BLL) in residents. A linear regression across
all of the data (all age groups) indicates a statistically significant relationship between blood
lead level and maximum measured lead in soil, though the effect level is fairly low (Figure
C.1). In other words, according to the regression results, it takes a big increase in measured
lead in soil (1,000 mg/kg) to produce a small increase in BLL (0.4 +/- 0.15 µg/dL).
Results are mixed when we separate the data set into three age groups and run the same
regression analysis (Figure C.2). The BLL-lead in soil relationship is not statistically
significant for the youngest age group (birth to < 6 yrs), but it does appear to be significant for
the older age groups (6 to 18 yrs and over 18 yrs). However, both of the older age groups have
a very high (over 4,000 mg/kg) sample result for lead in soil that is likely exerting a lot of
influence or leverage over the results.
The low effect levels between BLL and measured lead in soil reinforce the concept that there
could be many different sources and pathways of exposure to lead in the environment at the
site. It is appropriate to provide recommendations that highlight best practices for reducing or
eliminating exposure to lead from any known or likely sources (e.g., lead in paint, lead in
drinking water, airborne lead).
This analysis is limited by:
the small data set available for analysis (n=50 participants with BLL and measured
lead in soil results); when we separate the data into age groups for analyses, the data
sets are even smaller.
additional risk factors for higher BLL that are not accounted for (e.g., potential
exposure to lead-based paint, potential exposure to lead in the drinking water system,
potential exposure to airborne lead).
Figure C.1: Regression and Correlation Results: All Age Groups vs. Maximum Soil Lead
Level
Figure C.2: Regression and Correlation Results: Three Age Groups vs. Maximum Soil
Lead Level
Appendix D: PESHU Recommendations for Lead
Recommendations on Medical Management of Childhood Lead Exposure and
Poisoning
No level of lead in the blood is safe. In 2012, the CDC established a new “reference value” for
blood lead levels (5 mcg/dL), thereby lowering the level at which evaluation and intervention are
recommended (CDC).
Lead level
Recommendation
< 5 mcg/dL
1. Review lab results with family. For reference, the geometric mean blood lead level for
children 1‐5 years old is less than 2 mcg/dL .
2. Repeat the blood lead level in 6‐12 months if the child is at high risk or risk changes during the
timeframe. Ensure levels are done at 1 and 2 years of age.
3. For children screened at age < 12 months, consider retesting in 3‐6 months as lead exposure
may increase as mobility increases.
4. Perform routine health maintenance including assessment of nutrition, physical and mental
development, as well as iron deficiency risk factors.
5. Provide anticipatory guidance on common sources of environmental lead exposure: paint in
homes built prior to 1978, soil near roadways or other sources of lead, take‐home exposures
related to adult occupations, imported spices, cosmetics, folk remedies, and cookware.
5‐14 mcg/dL 1. Perform steps as described above for levels < 5 mcg/dL.
2. Re‐test venous blood lead level within 1‐3 months to ensure the lead level is not rising. If it is
stable or decreasing, retest the blood lead level in 3 months. Refer patient to local health
authorities if such resources are available. Most states require elevated blood lead levels be
reported to the state health department. Contact the CDC at 800‐CDC‐INFO (800‐232‐4636)
or the National Lead Information Center at 800‐424‐LEAD (5323) for resources regarding lead
poisoning prevention and local childhood lead poisoning prevention programs.
3. Take a careful environmental history to identify potential sources of exposures (see #5 above)
and provide preliminary advice about reducing/eliminating exposures. Take care to consider
other children who may be exposed.
4. Provide nutritional counseling related to calcium and iron. In addition, recommend having a
fruit at every meal as iron absorption quadruples when taken with Vitamin C‐containing foods.
Encourage the consumption of iron‐enriched foods (e.g., cereals, meats). Some children may
be eligible for Special Supplemental Nutrition Program for Women, Infants and Child (WIC) or
other nutritional counseling.
5. Ensure iron sufficiency with adequate laboratory testing (CBC, Ferritin, CRP) and treatment
per AAP guidelines. Consider starting a multivitamin with iron.
6. Perform structured developmental screening evaluations at child health maintenance visits, as
lead’s effect on development may manifest over years.
15‐44 mcg/dL 1. Perform steps as described above for levels 5‐14 mcg/dL.
2. Confirm the blood lead level with repeat venous sample within 1 to 4 weeks.
3. Additional, specific evaluation of the child, such as abdominal x‐ray should be considered
based on the environmental investigation and history (e.g., pica for paint chips, mouthing
behaviors). Gut decontamination may be considered if leaded foreign bodies are visualized on
x‐ray. Any treatment for blood lead levels in this range should be done in consultation with
an expert. Contact local PEHSU or PCC for guidance; see resources on back for contact
information.
>44 mcg/dL
1. Follow guidance for BLL 15‐44 mcg/dL as listed above.
2. Confirm the blood lead level with repeat venous lead level within 48 hours.
3. Consider hospitalization and/or chelation therapy (managed with the assistance of an
experienced provider). Safety of the home with respect to lead hazards, isolation of the lead
source, family social situation, and chronicity of the exposure are factors that may influence
management. Contact your regional PEHSU or PCC for assistance; see resources on back for
contact information.
Document authored by Nicholas Newman, DO, FAAP, Region 5 PEHSU, Helen J. Binns, MD, MPH, Region 5 PEHSU,
Mateusz Karwowski, MD, MPH, Region 1 PEHSU, Jennifer Lowry, MD , Region 7 PEHSU and the PEHSU Lead
Working Group.
Principles of Lead Exposure in Children
•
A child’s blood lead concentration depends on their environment, habits, and nutritional status. Each of these
can influence lead absorption. Children with differing habits or nutritional status but who live in the same
environment can vary on blood lead concentration. Further, as children age or change residences, habits or
environments change creating or reducing lead exposure potential.
•
While clinically evident effects such as anemia, abdominal pain, nephropathy, and encephalopathy are seen at
levels >40 µg/dL, even levels below 10 µg/dL are associated with subclinical effects such inattention and
hyperactivity, and decreased cognitive function. Levels above 100 µg/dL may result in fatal cerebral edema.
•
Lead exposure can be viewed as a lifelong exposure, even after blood lead levels decline. Bone acts as a
reservoir for lead over an individual’s lifetime. Childhood lead exposure has potential consequences for adult
health and is linked to hypertension, renal insufficiency, and increased cardiovascular‐related mortality.
•
Since lead shares common absorptive mechanisms with iron, calcium, and zinc, nutritional deficiencies in
these minerals promotes lead absorption. Acting synergistically with lead, deficiencies in these minerals can
also worsen lead‐related neurotoxicity.
Principles of Lead Screening
•
Lead screening is typically performed with a capillary specimen obtained by a finger prick with blood blotted
onto a testing paper. Testing in this manner requires that the skin surface be clean; false positives are
common. Therefore, elevated capillary blood lead levels should be followed by venipuncture testing to
confirm the blood lead level. In cases where the capillary specimen demonstrates an elevated lead level but
the follow‐up venipuncture does not, it is important to recognize that the child may live in a lead‐
contaminated environment that resulted in contamination of the finger tip. Efforts should be made to identify
and eliminate the source of lead in these cases. Where feasible, lead screening should be performed by
venipuncture.
Principles of Iron Deficiency Screening
•
•
The iron deficiency state enhances absorption of ingested lead.
Hemoglobin is a lagging indicator of iron deficiency and only 40% of children with anemia are iron deficient.
•
Lead exposed children (≥ 5 mcg/dL) are at risk for iron deficiency and should be screened using CBC, Ferritin,
and CRP. Alternatively, reticulocyte hemoglobin can be used, if available.
•
Children with iron deficiency, with or without anemia, should be treated with iron supplementation.
Resources
•
Pediatric Environmental Health Specialty Unit
(PEHSU)Network
•
www.pehsu.net or 888‐347‐2632
•
Poison Control Center (PCC)
•
www.aapcc.org/ or 800‐222‐1222
•
Centers for Disease Control and Prevention
•
www.cdc.gov/nceh/lead/ or 800‐232‐4636
•
U.S. Environmental Protection Agency
•
www.epa.gov/lead/ or 800‐424‐5323
Suggested Reading and References:
Pediatric Environmental Health, 3rd edition. American Academy of Pediatrics, 2012.
Woolf A, Goldman R, Bellinger D. Pediatric Clinics of North America 2007;54(2):271‐294.
Levin R, et al. Environmental Health Perspectives 2008; 116(10):1285‐1293.
Baker RD, Greer FR. Pediatrics 2010;126(5):1040‐50.
Guidelines for the Identification and Management of Lead Exposure in Pregnant and Lactating Women. CDC, 2010.
CDC Response to Advisory Committee on Childhood Lead Poisoning Prevention Recommendations in “Low Level Lead Exposure Harms Children: A
Renewed Call of
Primary Prevention” June 7, 2012
This document was supported by the Association of Occupational and Environmental Clinics (AOEC) and funded (in part) by the cooperative
agreement award number 1U61TS000118‐04 from the Agency for Toxic Substances and Disease Registry (ATSDR).
Acknowledgement: The U.S. Environmental Protection Agency (EPA) supports the PEHSU by providing funds to ATSDR under Inter‐Agency
Agreement number DW‐7592301301‐0. Neither EPA nor ATSDR endorse the purchase of any commercial products or services mentioned in
PEHSU publications.
(June 2013 update)
| File Type | application/pdf |
| File Title | Microsoft Word - Iola_KS-EI Report 8_2_2018 |
| Author | Lco6 |
| File Modified | 2018-10-17 |
| File Created | 2018-08-09 |