HomeMy WebLinkAboutSmuggler Superfund - Blood Lead Exposure to young children 1998 Univ of Concinnati Final Reportw
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BLOOD LEAD SURVEILLANCE AND EXPOSURE OF
YOUNG CHILDREN TO ELEVATED SOIL LEAD AT
THE SMUGGLER SUPERFuNiD SITE, AsWEN CO.
FINAL REPORT '
Prepared by: The University of Cbreinriiti
Prepared for: Pith County, FeteOh eirt ,
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October, 199$ ` A �
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EMARONMEWAL HEALTH
ASPEN J PITKfN
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TABLE OF CONTENTS
Page
I. Executive Summary
II. Workplan
1.0 Background................................................5
2.0 Study Objectives ............................................. 6
�« 3.0 Rationale .................................................. 6
3.1 Health Effects of Elevated Blood Lead 6
3.2 Benefits of an Independent Lead Study ..................... 8
4.0 Study Design ............................................... 9
4.1 Overview ............................................. 9
4.2 Sample Size ........................................... 9
4.3 Sampling Frame ....................................... 11
4.4 Selection of Study Participants .............................. 11
4.5 Activities Proposed for Fall, 1996 ............................ 13
4.6 Activities Proposed for Fail, 1997 ............................ 13
4.7 Timetable for the study ................................... 13
5.0 Methods..................................................14
5.1 Review of Protocol for Census .............................. 14
5.2
Overview of Protocol for Residential Environmental
Sample Collection ......................................
14
nA
5.2.1 Hiring and Training of Environmental Technicians ............
17
5.2.2 Environmental Survey in Temporal Order of Events ...........
17
5.3
Overview of Protocols for Environmental Sample Collection
18
5.3.1 Interior Household Surface Dust ........................
18
5.3.2 Handwipe Sample Collection ..........................
18
5.3.3 Exterior Surface Dust and Soil .........................
19
5.3.4 Quality Assurance Plan for Environmental Samples ............
19
v 5.4
Environmental Sample Analyses .............................
19
5.4.1 Environmental Sample Analysis Reference Methods ............
19
5.4.2 Acid Digestion for Analysis by Atomic Absorption ...........
20
5.5
Overview of Protocol for Blood Collection, Lead Analysis
and Quality Control .....................................
20
5.5.1 Sample Collection ................................
21
5.5.2 Sample Analysis .................................
21
5.5.3 Quality Assurance Plan for Blood Lead Analysis ............
21
5.6
Overview of Protocol for Clinic Interviews ......................
21
5.7
Data Management Procedures ..............................
22
5.8
Data Analysis.........................................
23
5.8.1 Descriptive Statistics ..............................
23
5.8.2 Inferential Techniques .............................
23
5.9
Reporting of Results from the Blood Lead and Residential
Environmental Survey ...................................
,
23
III.
Results and Discussion
6.0
Blood Lead Levels.......................................
24
6.1 Influence of Age...................................
24
6.2 Impact of Altitude/Hematocrit on Blood Lead .................24
6.3 Comparison with Previous Surveys ......... ..............
24
7.0
Environmental Lead Levels.................................
25
8.0
Hand Lead as an Exposure Indicator ...........................
25
9.0
Comparison of `96 and `97 Lead Exposure Data ...................
26
IV.
Summary of Results and Conclusions................................34
V.
References.................................................
35
VI.
Appendices
A.
Biological Sample Collection Protocol
B.
Consent Forms
C.
Data Collection Forms
D.
Individual Result Report Forms
E.
Environmental Sample Collection Protocol
F.
Influence of Altitude on Hematocrit, Blood Lead
and Body Lead Burden
G.
Aspen Individual Data Listing for 1996 and 1997
H.
Project Investigator and Key Personnel
I. Executive Summary
In the early 1980's elevated levels of lead were found in residential areas in and around the
Smuggler Trailer Court. In 1986, the site was placed on the Superfund National Priorities List.
i In 1990, the Agency for Toxic Substances and Disease Registry conducted a blood lead study to
examine the impact of environmental lead exposure on residents of the area. This survey found
no evidence of excessive lead exposure at that time. However, the number of children residing
in the area was quite small. Therefore concerned parties had limited confidence in making
assurances to the community that the true risk was low and would remain so in the future. The
Smuggler Mountain Technical Advisory Committee reviewed these data in 1993 and recommended
a two year blood lead assessment be conducted to confirm that there were no remaining excessive
health risks at the site. A legal consent decree stipulating the guidelines under which such an
assessment should be performed was agreed upon by EPA and Pitkin County. The University of
Cincinnati was retained by Pitkin County to conduct a follow-up study beginning in October,
1996. The main objectives of the study were:
to re-evaluate lead exposure following recent remedial actions which included
capping the berm and limited soil removal,
to assess the transfer of lead from soil to the interior of homes
to estimate the relative importance of various exposure pathways
to identify any children with blood lead levels equal to or above 10 µg/dl
Properties/homes in and around the Smuggler Trailer Court were randomly selected to yield a
geographically representative sample. In addition all families with children less than 84 months
of age were invited to participate in the study. A total of 40 properties were evaluated and 18
individuals, including 14 children less than 84 months old, were screened for possible blood lead
elevation.
Blood lead screening results reaffirmed the low blood lead levels previously reported for children
at this site. Their average blood lead was 2.7 ,cg/dl (range = 1.5 to 5.9 µg/dl) which is identical
to that reported in the most recent national survey. Sixty blood samples collected from young
children between 1990 and 1997 have yielded a maximum blood lead level of 8.4µg/dl, i.e., none
have exceeded 10 µgldl which is the EPA and Centers for Disease Control level of concern.
Elevated levels of lead in soils and street dusts were detected and 43 percent of the children
surveyed in 1996 had unusually high levels of lead in dust recovered from their hands. Apparently
some of the children are coming in contact with these elevated sources of lead in soil and dust but
it is having little or no significant impact on their blood lead levels.
Repeated blood lead monitoring of young children in the area with 40 of the most contaminated
sites at the Smuggler NPL site showed no increase in blood lead levels over the national
background level of about 2.7 µg/dl.
4
II. Workplan
1.0 Background
The Smuggler Mountain site, located one mile northeast of the city of Aspen, CO., Pitkin County,
has historically been an area of le4d and silver mining and milling. The mines, once a source of
employment for the surrounding community are now inactive and essentially abandoned. These
mining activities generated tailings and waste which were intermixed with native soil and spread
across areas where residential development eventually took place.
The Hunter Creek Condominiums, Smuggler Trailer Court and the Centennial Condominiums
were all constructed on top of and adjacent to surrounding tailing and waste piles. In the early
1980's elevated levels of lead and cadmium were found in these residential areas within and
surrounding the city. In 1984 the site was proposed for the Superfund National Priorities List
(NPL) and in 1986 placed on the Superfund List.
Much controversy exists regarding the risk to human health from metals in soil. In particular,
there is uncertainty regarding the bioavailability of metals present in mining waste, and therefore
uncertainty regarding human exposure. In several studies conducted in mining and milling
communities, correlation has been demonstrated between soil lead and blood lead of young
children. Weak indirect correlations have also been seen, where in soil lead is correlated with
house dust lead and house dust lead is correlated with blood lead.
The Smuggler Mountain Technical Advisory Committee in 1993 suggested a two year blood lead
(PbB) assessment should be conducted to confirm that there were no remaining excessive health
risks at the site. A soil bioavailability study conducted by EPA indicated a higher than expected
bioavailability of 35 percent, further substantiating the need for this assurance. Finally, a legal
consent decree stipulating the guidelines under which such an assessment should be performed was
agreed upon between EPA and Pitkin County.
�1
2.0 Study Objectives
The specific purpose of this investigation was to access lead exposure and low blood lead in
children residing at the Smuggler NPL site in Aspen, CO. Data were used to develop a final
remedial action that Drotects long-term health at the site. Secondarily, the amount of lead
transferred from the soil into the interior of the residences was assessed to estimate the relative
importance of exposure pathways.
The main objectives of the study were as follows:
.v
1. To re-evaluate lead exposure following recent remedial actions at the
site (e.g., capping the berm) and to estimate future childhood exposure
to yard -soil lead.
2. To identify any children with elevated blood lead levels (> 10 ,ugldl).
3.0 Rationale
3.1 Health Effects of Elevated Blood Lead
Children are known to be particularly susceptible to lead poisoning. Lead has been shown to
cause developmental problems in children when they are exposed to high enough concentrations
of lead over long enough periods of time. The effects are most pronounced for prenatal exposure
and for young children whose bodies are developing rapidly.
The toxicity of any substance depends on the magnitude, duration, and route of exposure.
Magnitude of exposure must be based not on the total concentration of substance present, but on
the concentration of bioavailable substance present. To be bioavailable, the substance must be
present in a chemical form which can be readily transported into and absorbed by the body. There
must also be a pathway present for transfer from the environment to the child, i.e., the substance
must be accessible. Primarily for these reasons, there is considerable uncertainty related to the
health effects of lead from mine tailings.
Previous studies conducted at other mining and milling sites have demonstrated that blood lead
levels of populations living in areas with elevated soil lead concentrations are no higher than those
of other populations in the United States. Several studies have been performed in the past several
years that have not shown a strong correlation between soil lead levels and blood lead levels in
children at these sites. A previous study of children residing near the Smuggler Mountain site,
where the average soil lead concentration was 1,370 mg/kg (ranging from 135 - 11,676 mg/kg),
found the arithmetic mean blood level to be 3.0 µg/dl. That study, conducted by the Agency for
Toxic Substances and Disease Registry and the Colorado Department of Health, found no
association between lead -containing mining wastes in soil and blood lead levels. Similarly, in
Butte, Montana (Bornschein et al. 1992), children who lived at residences with high soil lead
T
concentrations (ranging from 2,500 - 8,500 mg/kg) had average (geometric mean) blood lead
levels of 3.5 tzg/dl. Finally, in a 1989 study in Midvale, Utah (Bornschein et al. 1991), children's
average blood lead levels were 5.2 pg/dl, where concentrations of lead in residential surface soils
obtained in the study conducted by the University of Cincinnati ranged from 58 to 666.5 mg/kg.
. The most accepted method of measuring actual exposure to and uptake of lead in children's bodies
is through use of blood lead measurements. Several other methods, such as bone lead, can also
be used; however, there are problems with the other methods, such as the difficulty in obtaining
samples. A difficulty with blood lead measurements lies in their interpretation. Blood lead levels
rise and fall as exposures rise and fall; but since lead is retained in various body compartments for
differing lengths of time, a single measurement reflects both current and long-term exposure.
Despite this concern, the data show that if a child is exposed chronically to lead sources, blood
lead levels do provide a useful indication of lead exposure over the preceding months.
According to ATSDR, blood lead levels can provide information regarding the relative level of
exposure at more remote time periods (ATSDR, 1988). Repeat blood sampling over time, such
as takes place in prospective childhood lead studies (Bornschein, et al 1985) has revealed a high
degree of intercorrelation among repeat sampling. In fact, blood lead levels in 6.5 year olds are
correlated (r = 0.72) with lead exposures occurring five years earlier (Hawk and Schroeder et al,
1985; Mushak, 1989). This issue has also been examined in the Cincinnati Lead Study. Blood
lead measurements were made at three month intervals in over 300 children. For children over
one year of age, the correlation between their blood lead level at a randomly selected age (between
1 year and 6 years of age) and a blood lead obtained one year later is r=0.81. The correlation
between this randomly selected blood lead value and their average blood lead from birth to five
years of age is also 0.81. Blood lead measurements even reflect to some extent the level of lead
exposure incurred during the fetal period.
The geometric mean blood lead obtained in a large sample is a reflection of past and current
exposures of the average child in the community. Studies which have reported changes in blood
lead levels following some form of intervention report rather slow changes in blood lead. For
example, Succop et al (1987) estimated the half life of blood lead for 27 month old children
following a change of residence from a high lead to a low lead residential environment. The
estimated half life was found to be 11 months. Thus if a 27 month old child had a blood lead of
10 µg/dl and then moved to totally lead-free housing, his expected blood lead would be 5 jig/dl
after 11 months. If new housing was not totally lead free, the child probably would not reach 5
pg/dI. A recent examination of epidemiological and toxicokinetic evidence (Karam et al., 1993)
indicates that under relatively constant exposure conditions, blood lead measurements in a
population of young children at a site are stable over time.
A major advantage of measuring blood lead levels is that the Centers for Disease Control (CDC)
in Atlanta have established action levels which can be used to judge the results of blood lead
measurements. Specifically, the CDC has established 10 ,ug/dl (micrograms per deciliter) as the
level above which some concern is warranted. Blood lead levels above 15 µgldl are cause for
active intervention to locate and eliminate lead sources and/or pathways. Average blood lead
7
levels in children exposed to background levels of lead in air, water, and food typically range from
3 to 6 µg/dl. Although any single blood lead measurement above these values might be cause for
some action, blood lead studies are typically evaluated on a statistical basis. If 95 percent of the
population exhibits blood lead measurements below 10 µgldl, a significant community wide
problem is not generally considered to be present.
3.2 Benefits of an Independent Lead Study
A well-designed blood lead study in conjunction with an environmental lead survey provides the
best means of identifying lead -related health risks in a community. This independent study
conducted in the Smuggler Trailer Court area provided the information needed for a quantitative
assessment of potential risks to human health. It provided the site specific data required for use
with the uptake/biokinetic (UBK) model which EPA uses to predict blood lead concentrations in
a given population based on environmental lead concentration data and assumptions regarding lead
intake and absorption. Benefits of conducting the study included the identification of actual health
hazards, obtaining site-specific data for use in the EPA blood lead model, improving the scientific
database on lead bioavailability, and providing a community service.
E:?
4.0 Study Design
4.1 Overview
The study employed a cross-sectional design. Environmental and biological measurements were
made for each child and his/her resident. Environmental sampling occurred be in and around
: residences occupied by study participants. Additional environmental samples were taken from
20% of the homes within the site to establish the possibility of an exposure pathway. Regression
techniques were used to relate blood lead measurements to environmental lead measures.
The study contained the following components:
• Demographic survey
• Environmental Survey
• Environmental Media Sampling
• Blood Sampling and Analysis
• Hand Wipe Analysis
• Data Analysis and Interpretation
• Report Preparation
• Community Outreach
• Response to Participants
r EPA, the State of Colorado, and the Aspen/Pitkin County Environmental Health Department
participated in development of the work plan and protocol review. A key component to the
success of the project was the participation of the local agencies and community leaders.
Participation by the local environmental health department and the support of community leaders
encouraged resident participation.
4.2 Sample Size
One of the study objectives was to estimate the community mean blood lead for children less than
or equal to 84 months of age. If a community geometric mean of 2µg/dl and a geometric standard
deviation of the blood lead distribution of 1.7 µg/dl is assumed, then a sample size of 10 will yield
an estimate of the geometric mean blood lead with a precision range of 1.3 µg/dl (95 % confidence
limits = 1.5 - 2.8). Note that reference to precision is an estimate of the error of the population
mean, not reference to analytical precision. The number of children in this neighborhood is
limited, thus a less precise estimate of the mean blood lead for this neighborhood was detained .
However, it was still possible to identify individuals at risk due to elevated blood lead levels.
Thus sampling in a low population area is still warranted. See Table 4.2.1 for precision estimates
for other size samples.
Table 4.2.1: 95 Percent Confidence Limits for a Geometric Mean Blood Lead of 4 ,ug/dl
and Various Sam le Sizes
Estimated Geometric
Sample
95 % Confidence*
Mean Blood Lead
Size
Limits of the Estimate
10
1.5-2.8
2 µg/dl
25
1.7-2.4
50
1.8-2.3
100
1.8-2.2
200
1.9-2.1
10
2.9-5.4
4 µg/dl
25
3.3-4.8
50
3.5 -4.5
100
3.7-4.4
-
200
3.8-4.2
10
4.4-8.1
6 µgldl
25
5.0-7.2
50
5.3-6.8
100
5.5-6.5
200
5.6-6.3
*Thus calculation assumes a geometric
standard deviation of the mean of 1.7 µg/dl.
10
4.3 Sampling Frame
Study participants consisted of children, less than or equal to 84 months of age, currently residing
in the study area selected. Study enrollment was voluntary. Pregnant women and mothers nursing
young infants were invited to have their lead levels checked. Since the number of pregnant or
lactating women was limited, obtaining a highly precise estimate of the mean and distribution of
blood lead levels for these groups was not possible.
This study did not employ a control group selected from outside the proposed study area. By
definition, a control group should be identical to the study group in all aspects considered relevant
to the key outcome variable, e.g., blood lead, with the exception of the key independent variables
(environmental lead measures). The multivariate nature of the childhood lead exposure mitigates
against finding true control groups. There is considerable uncertainty regarding soil lead
concentrations in any potential control area. The Smuggler area has been influenced by milling
and mining operations at various times during the past 100 years. Soils may have become
contaminated to a largely unknown degree and in ill-defined patterns as a result of these activities.
Furthermore, working parents may have carried metal contaminants home in the form of dust on
their clothing, shoes, or automobiles. This could result in the contamination of residential units
scattered throughout the area. Thus, it is impossible to select a control area with any certainty that
it is not also contaminated to some extent. Selection of a control area in the absence of good
g ° residential environmental lead data could result in a spuriously high estimate of background blood
lead levels. Most importantly, the purpose of the study was not simply to demonstrate that the
average blood lead in a study area is significantly different from a "control" area. Rather, child -
specific lead sources in each study area were measured and statistically modeled to determine the
relative impact of these sources on the blood lead of residents. Estimates of the impact of various
independent variables (soil lead, exterior and interior dust lead, etc.) were developed using
regression techniques.
4.4 Selection of Study Participants
Since the study area was confined and the number of children small (n=14), a door-to-door
census was not undertaken. Study participation was strictly voluntary following a description
of the study and signing of an agreement to participate (see Consent Form - Appendix B).
Residents living outside the proposed study area were not actively recruited. However, if they
requested a blood lead screening test, they were not refused, nor were residents living in the study
area who did not have children less than seven years old and who had not been selected for
' environmental sampling. See Figure 4.4.1- Map of Study Area. In addition to actively recruiting
families with young children an effort was made to obtain a spatially representative sample of
homes for residential lead assessments. To this end, every fifth homeowner on each street was
requested to participate. If he or she declined, an adjacent homeowner was approached. This
procedure yielded a sample of 38 homes distributed across the study area. Two families living
near the trailer court also requested that their homes be sampled.
11
4.5 Activities Proposed for Fall, 1996
The survey planned for the fall of 1996 consisted of a full census of the trailer court in order to
identify all age eligible children. A spatially stratefied random sample of mobile homes was
selected for full environmental sampling. In addition, all families with at least one age eligible
child, were recruited into the study. As result of this strategy, 40 of 136 homes were targeted for
sampling, including 10 homes with 14 children.
4.6 Activities Proposed for Fall, 1997
Sampling in 1997 was restricted to 8 homes with age eligible children tested in 1996.
Environmental samples were restricted to floor dust, and hand dust. Blood samples were collected
on children previously tested plus several sibs not tested in 1996.
4.7 Timetable for the Study
The study was conducted in October of 1996 and October of 1997 and took approximately one
week to complete. The following is the overall project schedule:
Activily
Timing
Develop Work Plan and QA Plan
Aug. -Sept., 1996
Meet with Local Health Dept.
April, 1996
Invite EPA Input
Aug., 1996
Finalize Survey Forms and Questionnaire
Sept., 1996
Complete Sampling Protocols
Sept., 1996
Organize Field Office
Sept., 1996
Conduct Demographic Survey and Environmental
Sept. -Oct., 1996
Sample Collection
Conduct Error Checking and Data Entry
Oct., 1996
Collect and Analyze Blood Samples
Sept. -Nov., 1996
Enter Biological and Environmental Results
Dec., 1996
Communicate Results to Participants
Jan., 1997
Communicate Results to Community
May, 1997
Conduct Follow-up Blood and Dust Survey
Sept. 1998
Prepare Report
1998
Submit Final Report
Oct. 1998
13
5.0 Methods
5.1 Review of Protocol for Census
Two, two -member teams were used in the collection of demographic and environmental data. All
technicians underwent thorough training on methods used to obtain reliable and complete data.
Appointments were made for each environmental visit. In the event no one was home, the teams
made at least three additional attempts to contact the resident on different days and times of day.
The following information was obtained by interview during the visit:
1. Current address.
2. Names and ages of all children under six years of age residing at the residence.
3. Pregnant and/or nursing mothers.
4. Duration of residence at current address.
5. Prior address and duration of residency.
6. Type, age and condition of current housing.
5.2 Overview of Protocol for Residential Environmental Sample Collection
The environmental survey was designed to sample the various media which might contribute to
a child's lead exposure from a variety of non -household and household sources. The media
sampled included household interior surface dust, exterior surface dust, and soil. Details of
methods development and application in other metal exposure situations can be found in Que Hee
et al., 1985; Clark et al., 1985; Bornschein et al., 1985; Bornschein et al., 1986; Bornschein et
al., 1989, Butte -SBDOH and UCDEH, 1992, Leadville, 1992 and Bingham Creek, 1994. The
principle variables of interest and their units are listed in Table 5.2.1. (Also see Appendix E -
Environmental Sample Collection Protocol - for more detail).
Figure 5.2.1 shows the type and location of samples collected at each residence.
14
Table 5.2.1: Key Variables Measured during the Aspen, CO. Study*
Name - Type Units
Residential interior surface dust lead
Residential exterior surface dust at entry
Soil lead - house perimeter
House type (and condition)
House Age
Dust loading
Social and Demographic Variables:
Socio-economic status (Hollingshead 4 -factor)
Child's age
Age squared (quadratic term)
Duration of residency
Parental lead -related occupations
Parental lead -related hobbies
Frequency of child's mouthing behaviors
Indoor/Outdoor activity distribution
Outcome Variable:
Blood lead
Handdust lead
Continuous
Continuous
Continuous
Discrete
Continuous
Continuous
Continuous
Continuous
Continuous
Continuous
Discrete
Discrete
Discrete
Continuous
Continuous
Continuous
µg/g or µglcm2
µg/g or µg/cm2
ILglg
years
mg/cm2
months
months2
months
hours
µg/dl
µg
*These represent the major variables of concern. However, many other factors will be measured
and can be found on data collection forms in Appendix C.
15
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5.2.1 Hiring and Training of Environmental Technicians
Two member teams were used for the collection of environmental samples and the interview of
residents for the study. These technicians were University employees who had previous
experiences in field -related activities such as this study. Training of this staff occurred the week
prior to the start of the field study.
All environmental technicians were uniformly trained in the collection of all types of
environmental samples. Training occurred in each of the following areas.
1. Project orientation, field office organization, data recording, and safety issues.
2. Soil and exterior dust collection and exterior layout sketching.
3. Interior dust collection and floor plan drawing.
4. Hand dust collection.
5. Blood collection
During sample collection, a typical survey required a team to collect both interior and exterior
samples. During inclement weather, when it is not possible to collect exterior dust and soils
samples, the teams collected interior samples. As weather conditions changed and it became
possible to collect exterior samples, the teams made arrangements to collect exterior samples.
Initial appointments to survey study homes were made from Cincinnati. Once on site, teams were
provided with addresses, names, and all necessary sampling materials. All team members were
provided with temporary staff identification badges.
5.2.2 Environmental Survey in Temporal Order of Events:
Environmental surveys required 60 to 120 minutes to conduct. Surveys were carried out by a team
in the following order:
1. Introduction and preliminary residential walk-through.
2. Interview of parent (Form 12) and child activities questionnaire.
3. Collection of blood from any eligible children or by request.
4. Sketch of interior floor plan and selection of sampling sites.
S. Interior surface dust sample collected (one composite floor dust sample).
b. Inspection and sketch of layout of exterior.
17
7. Collection of exterior soil cores and exterior dust samples (entry and street).
8. Collection of hand dust wipes.
9. Closing comments to family.
5.3 Overview of Protocols for Environmental Sample Collection
5.3.1 Interior Household Surface Dust
interior surface dust was sampled using a small vacuum pump to obtain dust from measured areas
(Que Hee et al, 1985). The lead content of the dust was expressed as both µgig (weight content)
and tcg/m' (area content). The relative dustiness of the residence was expressed as weight of dust
collected per unit area.
A composite sample was obtained from three measured areas (625 sq. cm each) in the residence.
These areas were meant to represent areas frequented by the children. The areas were:
1. A floor area directly inside of the main entry to the residence.
2. A floor area in the most frequently occupied room (usually living room or kitchen).
3. A floor area in the child's bedroom.
Field duplicates were collected at 23 percent of the residences ( n=9).
5.3.2 Handwipe Sample Collection
Collection of the hand -dust samples was done at the conclusion of each visit to a residence.
Preliminary data indicate that hand dust equilibrates with a given environment within two hours.
Therefore, the location and activities of the children immediately preceding the testing are
important and were noted.
The person collecting the hand -dust samples wore disposable gloves and cleaned his/her own
hands with a disposable wipe from a separate container of wipes kept for this purpose before
touching the gloves or other equipment. Once the gloves were put on, they were cleaned well,
using additional clean wipes. For each residence, where one or more child's hands were sampled,
a field blank was taken. This was done in the following manner. Six wipes were removed from
the container, handled to simulate wiping a child's hands and then placed in a single bag and
submitted for analysis.
Dust on children's hands was sampled by wiping each hand of the child with three separate
commercial Wet -Wipes. All surfaces of the hand, front and back, up to the wrists, were wiped
18
thoroughly with each of the three wipes. The wipes from each child were composited in a single
sealable bag for transport to the laboratory. The total quantity of lead was reported in µg/pair of
hands.
The materials used to collect hand -dust were as follows: a commercially available wipe which
contains a number of ingredients was used (Walgreen's Brand Wet -Wipes). A polypropylene, zip
loc bag was used to contain the sample. Fisher Scientific Disposable Latex gloves are worn.
5.3.3 Exterior Surface Dust and Soil
Two types of samples were obtained, representing different surface conditions. Soil cores of 2
cm depth were taken in grassy areas. A composite sample of soil cores were taken from grassy
yards adjacent to a residence i.e. from the front, back and sides, with 8 to 12 samples per
composite. Cores were taken at approximately equal spacings along the sides of the building, at
a distance of one meter (3 feet) from the building wall. Small lot sizes and fences in some
neighborhoods precluded taking building perimeter samples at a distance of one meter on some
properties. Composite surface dust samples were taken with a vacuum apparatus on paved areas,
and other hard surfaces near building entries, e.g., at front and rear entrance Field duplicates
were collected at 23 percent of the sample sites.
5.3.4 Quality Assurance Plan for Environmental Samples
Details of the quality control plan for environmental samples, including sample custody and
specific routine procedures to assess data precision, accuracy and completeness are found in a
separate document: "Blood Lead Surveillance and Exposure of Young Children to Elevated Soil
Lead at the Smuggler Superfund Site, Aspen, CO. Quality Assurance Plan".
As part of the quality assurance plan for this study, 23 percent of the homes surveyed were
randomly selected for resurvey. One or more randomly selected homes were resurveyed each day
during the environmental assessments. Upon completion of the routinely scheduled survey, the
survey team at the preselected house undertook a complete resampling of the home. Since
sampling teams were randomly assigned to survey homes, different teams conducted the resample
each day. A comparison of data from initial versus repeat sampling at those homes yielded a
measure of the reproducibility of the environmental data.
5.4 Environmental Sample Analyses
The interior dust, exterior dust, soil and handwipe samples were fowarded to the Hematology and
Environmental Laboratory at the University of Cincinnati for analysis. These samples were
analyzed by atomic absorption spectroscopy (AA). Details for the analysis of these samples were
found in "The Hematology and Environmental Laboratory's Quality Assurance Plan" which is
available upon request.
5.41 Environmental Sample Analysis Reference Methods
Environmental samples were analyzed by atomic absorption (AA) or (XRF). Method validation
19
includes cross checks with inductively coupled plasma emission spectroscopy (ICP) or AA.
Unless otherwise noted, the methods were consistent with EPA Test Methods for Evaluating Solid
Waste Vol. IA: Laboratory Manual, Physical/Chemical Methods.
Method 3020 & 3050 Preparation of samples for total metal determination by graphite
furnace AA (3020) direct aspiration AA (3050) or 1CP (3050).
Method 5010 & 2000 Basic analytical methods for analysis by inductively coupled plasma
atomic emission spectroscopy (6010) or atomic absorption (2000).
Method 7420 & 7421 Lead analysis by direct aspiration (7420) or graphite furnace (7421).
5.4.2 Acid Digestion for Analysis by Atomic Absorption
Weigh an aliquot of 100 mg sieved, dried soil or dust into a tared, acid -washed 100 ml beaker.
Add 25 ml 7N HNO3, cover and digest gently at 95' degrees C for two hours, stirring
occasionally. if excessive foaming occurs, remove from the heat periodically until foaming
subsides. Maintain at least 25 ml in the beaker by adding 7 N HNO3 as necessary.
Cool. Filter through a plastic funnel with Whatman No. 54 filter paper into a 100 ml beaker.
Rinse filter and labware with IN HNO3 to effect a quantitative transfer. Place the covered samples
on a hot plate and take down to dryness at 95°C. Add 3 ml of 1N HNO3 to redissolve arsenic.
Gently heat on hot plate for 5-10 minutes. Cool. Pour the sample into 10 ml cylinder. Add 3
rinsings of the original sample beaker to the cylinder. Dilute to 10 ml volume.
This portion of the sample was delivered to the Analytical Laboratory for GFAAS analysis.
Samples were diluted with 1.0 M nitric acid to bring the sample concentration within the linear
range of the instrument. After samples were analyzed, the lead concentration was calculated and
the results reported in ppm.
5.5 Overview of Protocol for Blood Collection, Lead Analysis and Quality Control
Whole blood samples was collected by a trained pediatric phlebotomist for the analysis of lead and
hematocrit. For these analyses, a maximum of 2 ml of blood was obtained by using venipuncture
blood collection techniques. One person was designated to oversee the collection and record
keeping of these samples, make the necessary preparations for analyses, and be sample custodian.
20
5.5.1 Sample Collection
Venipuncture samples were drawn using a 23 gauge butterfly apparatus attached to a 6 ml
disposable syringe. Blood was immediately dispensed into a K3EDTA containing pediatric
vacutainer tube by insertion of the needle through the top of the tube. The tube itself was then
inverted several times to mix the anticoagulant. All blood sample collection equipment was
prescreened for possible lead contamination.
5.5.2 Sample Analysis
All samples were analyzed for lead in triplicate using anodic stripping voltommetry (ASV).
Analyses were conducted at the University of Cincinnati using the method of Roda et al., 1988.
Quality control samples prepared in the Cincinnati laboratory were included in all analytical runs.
These samples consisted of human blood samples with lead content determined by isotope
dilution -mass spectrometry, the definitive lead method. Samples whose duplicate lead values
differed by more than 3 gg/dl were reanalyzed. This occurred in less than 2 percent of the
samples.
5.5.3 Quality Assurance Plan for Blood Lead Analysis
Details of the quality control plan for blood lead analysis including sample custody and specific
routine procedures to assess data precision, accuracy and completeness can be found in the "Blood
Lead Surveillance and Exposure of Young Children to Elevated Soil Lead at the Smuggler
Superfund Site, Aspen, CO. Quality Assurance Plan and The Hematology and Environmental
Quality Assurance Plan" which are available upon request. (Also see Appendix G - Overview
of Blood Lead QC Plan - for more details.)
5.6 Overview of Protocol for Clinic Interviews
Staff involved in interviewing parents were experienced interviewers who had undergone specific
training with respect to the questions and information being sought for this study.
Examples of information obtained during the interview include the following:
1. Parental occupation and education.
2. Recent major renovation at current or prior address (if during last twelve months).
3. Frequency of childhood habits such as mouthing behavior and pica.
21
4. Use of tailings or mine waste as fill material at any site on the residential lot.
5. Lead -related hobbies or occupations.
5. Time spent at day care centers or secondary residences.
7. Time spent at community playgrounds.
Many other questions were asked and examples can be found in Appendix C.
5.7 Data Management Procedures
Numerous procedures were utilized for insuring the validity of the collected data. Staff were
trained in appropriate procedures for completing forms. One member of the research team
completed the form, while a second member reviewed the form for errors. Forms used for this
survey can be found in Appendix C. The forms were then forwarded to the data auditor who
verified the legibility and completeness of the entries. Forms were then delivered to the data entry
personnel. Data were be entered into Macintosh PC's for storage and preliminary analysis. Data
was be entered and re -checked twice, each time by a different staff member.
Computerized data files were pre-processed (checked) for certain types of data entry errors. A
computer program was used to check the accuracy of identification information (subject
identification number; data; child's age in months; etc.), presence of possible missed entries, and
completeness of the file.
The pre-processed data were then entered into the permanent (disk) data base and were
concatenated with any data already resident to the data base. A range check was performed to
locate serious entry errors.
A printout of the newly entered data was then provided to each of the project personnel who
initiated the paper forms. Reviews of the newly entered data for each form type was then
performed, and any errors in the data residing in the permanent data base corrected. All changes
to the permanent data base were thoroughly documented.
Before major statistical analyses were performed on any of the data, univariate analyses of the
frequency distributions was reviewed. These descriptive statistics provide valuable information
for choosing the best variable specification (transformation of the observed frequency distribution,
e.g. log, square root, etc.) for each variable in the data base. The techniques also aided in
discovering possible spurious outliers or errors that were not identified by one of the previously
mentioned data entry procedures.
22
5.8 Data Analysis
5.8.1 Descriptive Statistics
The frequency distribution of blood lead and the environmental data was plotted for visual
inspection. Frequency histograms revealed that the distributions of lead in blood and lead in
environmental samples were distributed log -normally. Blood lead and environmental lead data
were transformed to their natural log equivalent and estimates of the sample geometric mean and
geometric standard deviation obtained. These distributions were compared to available national
norms (Mahaffey et al., 1982); National Health and Nutrition Examination Survey III - expected
summer, 1993; and The Centers for Disease Control Guidelines (Preventing Lead Poisoning in
Young Children, 1991) and other surveys. Simple bivariate correlations among the exposure
variables, covariates, confounders and dependent variables were then calculated.
5.8.2 Inferential Techniques
The small sample size in both the 1996 and 1997 precluded rigorous hypotheses testing due to low
statistical power. Therefore it was not possible to derive exposure pathway models or carry out
even simple multiple regression analyses. Analyses were limited to simple t-tests and correlations.
5.9 Reporting of Results from the Blood Lead and Residential Environmental Survey
Parents of the children tested were notified in writing of the blood lead results. Interior surface
dust lead and exterior soil core lead concentrations were provided to families in summary reports
prior to the public release of the final report. Forms used to report individual results to parents
can be found in Appendix D.
23
III. Results and Discussion
6.0 Blood Lead Levels
6.1 Influence of Age
There were a total of 14 children less than 84 months of age living in the Smuggler Trailer Court
at the time of this study. All of these children from 10 families participated. In addition, 30 other
families living in or near the trailer court participated in the environmental screening phase of this
study. The average blood lead among the young children was 2.7 µg/dl (range = 1.5 to 5.9
,ug/dl). Older siblings and adults had comparably low blood lead levels (see Table 6.1).
A resurvey of these children in 1997 found that the average blood lead had fallen to 2.1 µg/dl
(range = 1.3 to 2.9 µg/dl). Individual data for both 1996 and 1997 are reported in Appendix G.
There was no significant age trend among children less than 84 months of age.
6.2 Impact of Altitude/Hematocrit on Blood Lead
Many sites in this country, where children are exposed to waste from mining, milling and/or
smelting activities, are located at high elevations in the western U.S. Aspen, CO at an elevation
of 7,981 feet above sea level, is such a community. At these high elevations, the body responds
to the lower oxygen concentration by producing more red blood cells in order to increase the
ability of the blood to carry oxygen. This has consequences for the distribution of lead in the
body, as well as for how we interpret the health consequences of a given level of lead in the body.
About 95 percent of all lead in blood is bound to red blood cells. As the percentage of red blood
cells in whole blood (hematocrit) increases, the number of binding sites for lead increases. Thus,
the higher the hematocrit, the higher the blood lead concentration, even though the amount of lead
bound to a single red blood cell remains the same. To illustrate the impact of this effect, assume
two identical children, with identical lead exposures. One child lives at sea level with a hematocrit
of 35 percent and a blood lead of 8.5 Mcg/dl, the other living in Aspen at 7,981 ft. would have a
hematocrit of 42 percent and a blood lead of 10.2 µg/dl (20 % higher). Health scientists interpret
a blood lead of 10 µgldl as being a level of concern based on numerous developmental studies
carried out in communities at or near sea level, where children have hematocrits of about 35 %.
We do not know if chronic blood lead levels of 10 ,ug/dl in children living at high elevation pose
the same risk as that which has been studied at sea level. Conversely, children with chronic
anemia have lower hematocrits (30-35 %) and might be at greater risk than would otherwise be
inferred from a chronic blood lead level of 8 or 9 µg/dl. Physiologically based pharmacokinetic
modeling might shed some light on this issue (see Appendix F).
6.3 Comparison with Previous Surveys
It is informative to compare the 1996 and 1997 blood lead surveys with previous surveys
conducted at this site, as well as with a recent national survey. The ATSDR conducted a
comprehensive assessment in 1990. That survey of 28 children less than 6 years old found no
children with blood lead levels above 10 jg/dl, while the group average was 2.6µg/dl. This low
average blood lead level was unexpected given the high levels of lead in soil and exterior dust.
24
There were no recent national survey data available in 1990 and this value of 2.6 µg/dl was
thought to be far below the national average. In 1992, the University of Cincinnati retested
children from two families. Again the blood lead levels were quite low. No further systematic
survey took place until 1996-97. The results of the earlier surveys and the current surveys are
shown in Table 6.3. As can be seen, the average blood lead level remains low. In 1994, the
results of a national survey were released (Pirkle et al. 1994). These results indicated that the
children living in the Smuggler Trailer Court were in fact typical of young children participating
in the NHANES III survey.
1 7.0 Environmental Lead Levels
Environmental data collected during the 1996 survey are presented in Table 7.1. Two trends are
apparent: (1) homes surrounded by soils with lead greater than 1000 ppm have higher levels of
lead in entry dust and floor dust than other categories of soil lead and (2) soils and street dust lead
y have higher concentrations of lead than exterior entry dust which is in turn higher than the interior
floor dust. The floor dust lead loadings and exterior entry dust lead loadings are substantially
lower than the proposed EPA/HUD standard of 50 µglft' or 540 µglm2. The highest observed
floor dust lead loading was 367 µg/m' found in unit #3 in 1996. Street dust lead and entry dust
lead loadings were also highest at this unit, 4784 and 202 µghn , respectively. The child residing
in this unit was 29 months old and had the highest observed blood lead of 5.9 µg/dl.
Despite the high soil lead and street dust lead levels, children's blood lead levels are low and
stable over time, perhaps in part due to the very low levels of lead in floor dust. It should be
noted that these mobile homes contain no lead paint and are well maintained.
Table 7.2 illustrates the degree of association among various sources of lead in the environment
and indicators of lead exposure, i.e., hand dust lead and blood lead. Correlation among
environmental sources is high as was expected based on previous studies at similar sites. The
environmental sources were not significantly associated with hand dust lead or blood lead. This
is due to the small sample size and lack of statistical power. The correlations are positive and of
a strength similar to that seen at other sites. It is likely that if more children lived at this site and
participated in the survey it would have been possible to demonstrate that lead in soil and dust was
having a small but measurable impact on children's blood lead level. Children living in homes
with soil lead above 1000 ppm appear to have blood Ievels which average about 0.5 µg/dl higher
than children exposed to less than 1000 ppm.
8.0 Hand Lead as an Exposure Indicator
The hand dust lead data presented in Table 7.1 was surprisingly high given the low blood lead
levels seen in the children. In 1996 six of 14 children tested had hand dust lead levels above 10
µg. There is no standard for hand dust lead. However, studies by the University of Cincinnati
indicate that hand dust lead greater than 10 Ag/pair of hands is likely to be associated with a blood
lead level above 10 µg/dl in young children. Table 8.1 shows average hand dust lead and blood
lead levels and their correlation at sites investigated by the University of Cincinnati. In general,
as average hand dust lead increases, average blood lead increases. However, the data from Aspen
appear to be anomolous. Based on a group average hand dust level of 8.8 µg (Table 7. 1), average
25
blood lead levels would be expected to average 10-11 µgldl. Instead the average blood lead level
in 1996 was 2.7 µgldl, a level which is usually associated with average hand dust lead levels of
2-3 µg. The correlation between hand dust lead and blood lead was also weaker than expected in
1996 (r=0.20). A review of records indicated that several children were sampled immediately
prior to leaving home for preschool and several others were sampled immediately after returning
home from preschool. This is not the normal protocol which calls for children to be sampled after
remaining indoors for about one hour. The necessary deviation from protocol might have
introduced a greater than normal amount of variability in hand dust lead, thereby reducing the
association with blood lead.
u These data clearly indicate that the children living in the Smuggler Trailer Court have come in
contact with lead in dust and soil near their homes. However, this exposure is not resulting in the
expected blood lead elevations, either due to a low hand-to-mouth activity or a dietary condition
which is reducing lead absorption. In either case, there is no evidence that lead in soil and dust
is causing elevation in blood lead levels which pose a health threat.
9.0 Comparison of `96 and `97 Lead Exposure Data
Table 9.1 summarizes the change in exposure levels which were observed between the 1996 and
1997 surveys. This analysis is based on 13 children in 8 homes which participated in both
surveys. Floor dust lead, hand lead and blood lead all declined in the second year of the survey.
The hand dust and blood lead levels declined by about 25 percent, while floor dust lead
concentrations (ppm) and loading (µg/m) declined by about 45 percent. The blood lead and dust
lead concentrations declines were small but statistically significant.
26
Table 6.1
Blood Lead Levels (ug/dl)
Smuggler Mountain Site (1996),
Table 6.2
Hematocrit Levels (%)
N
Geometric
Mean
GSD
Mininum
Maximum
less than 36 mo.
4
2.57
1.80
1.5
5.9
36 mo. - 84 mo.
10
2.80
1.35
1.5
4.3
less than 84 mo.
14
2.73
1.46
1.5
5.9
7 yr. - 18 yr.
2
2.24
1.12
2.1
2.4
greater than 18 yr.
2
2.57
1.79
1 1.7
1 3.9
Table 6.2
Hematocrit Levels (%)
27
N
Artithmetic
Mean
S.D.
Mininum
Maximum
less than 36 mo.
4
40.5
2.89
37
44
36 mo. - 84 mo.
10
42.3
2.45
39
46
less than 84 mo.
14
41.8
2.61
37
46
7 yr. - 18 yr.
2
41.5
0.71
41
42
greater than 18 yr.
2
49.5
0.71
49
50
27
Table 6.3
Comparison of Aspen Surveys with Recent National Blood Lead
Survey Data (Pirkle et al. 1994)
'Pirkle, J.L., Brody, D.J., Gunter, E.W., Kramen, R.A., Paschal, D.C., Flegal, K.M.,
Matte, T. D. (1994). The decline in blood lead levels in the United States: The National
Health and Nutrition Examination Surveys (NHANES). Journal of the Amer. Med. Assoc.
272:284=291.
bresample of 3 children tested in 1990 and one child born since 1990
28
Average Blood Lead
% Greater than 10 ,ug/dl
NHANES III:
1-5 yr. olds (N = 2392)a
2.7 ggl dl
4.4%
Aspen Surveys:
1990 (N = 28)
2.6
0
1992 (N = 4)a
3.3
0
1996 (N = 14)
2.7
0
1997 (N = 14)
2.1
0
'Pirkle, J.L., Brody, D.J., Gunter, E.W., Kramen, R.A., Paschal, D.C., Flegal, K.M.,
Matte, T. D. (1994). The decline in blood lead levels in the United States: The National
Health and Nutrition Examination Surveys (NHANES). Journal of the Amer. Med. Assoc.
272:284=291.
bresample of 3 children tested in 1990 and one child born since 1990
28
Table 6.4
1990 versus 1996-97 Aspen Blood Lead Survey
acategories based on soil lead characterization obtained in earlier surveys and shown
on Pitkin Co. GIS map dated 4/16/96.
29
Average
% Greater than
Blood Lead
10 ,u /dl
1990 ATSDR Study
Soil Lead less than 500 ppm (N = 9)
3.6
0
Soil Lead 500-1000 ppm (N = 14)
2.4
0
Soil Lead greater than 1000 ppm (N =4)
3.9
0
1996 U.C. Study'
Remediated Soils (N = 5)
2.5
0
Low Lead Soils (N = 4)
2.9
0
Partial Soil > 1000 ppm (N = 0)
--
--
All Soil > 1000 ppm (N = 5)
3.3
0
1997 U.C. Study
Remediated Soils (N=7)
2.0
0
Low Lead Soils (N=3)
1.9
0
Partial Soil >I 000 ppm (N=0)
--
--
All Soil > 1000 ppm (N = 4)
1 2.5
1 0
acategories based on soil lead characterization obtained in earlier surveys and shown
on Pitkin Co. GIS map dated 4/16/96.
29
Table 7.1
1996 Aspen Data Summary'
Property Type'
'All values reported as geometric means
'Categories based on soil lead characterization obtained in earlier surveys
and shown on Pitkin Co. GIS map dated 4116196.
30
All
Partial
Abated
Low
All
Soil Lead
Soil Lead
Soils
Soil
Properties
> 1000
> 1000
Lead
Ppm
PPm
SamleT pe
Units
n=17
n=11
n=5
n=7
n=40
Foundation Soil
916
446
337
262
540
PPM
Street Dust
ppm
812
322
322
127
423
Street Dust
Lead Loading
�cglm2
599
252
273
106
320
Exter. Entry
Dust Lead
Conc.
ppm
521
257
86
245
300
Exter. Entry
Dust Lead
Loading
uglm2
227
62
59
132
120
Floor Dust
Lead Conc.
ppm
365
188
148
194
239
Floor Dust
Lead Loading
4g/m2
153
74
69
63
91
Floor Dust
Loading
mg/m2
420
393
477
322
383
Hand Dust
,ig
11.7
---
6.0
10.0
8.8
Blood Lead (N)
4gldl
3.03(5)
---
2.41 (5)
2.81 (4)
2.73 (14)
'All values reported as geometric means
'Categories based on soil lead characterization obtained in earlier surveys
and shown on Pitkin Co. GIS map dated 4116196.
30
Table 7.2
Correlations Among Environmental Lead Sources and
Indicators of Children's Lead Exposure (1996 Survey)
*statistically significant (p C .05)
41997 survey r=.36; p=0.19
'1997 survey r=.41; p=0.13
31
Exterior Entry
Dust
Floor Dust
(ppm)
Hand Dust
(ppm)
Blood
Lead
(ug/dl)
Foundation
Soil
—(PPM)
.67*
.58*
-.10
.28
Street Dust
.56*
.50*
.17
•37
Entry Dust
-
.61 *
.35
.32
Floor Dust
-
-
• 23
.42a
Hand Dust
-
-
-
20'
*statistically significant (p C .05)
41997 survey r=.36; p=0.19
'1997 survey r=.41; p=0.13
31
Table 8.1
Comparison of Average Hand Lead and Blood Lead Levels
of Children < 36 Months of Age at Different Sites
eN=14; p=.46 ep=0.13
32
Hand Lead
Blood lead
Age
Correlation
Gig)
,u dl
(months)
r
Sandy, Utah
(1994)
2.3
3.2
18.5
0.08
Bingham Creek, Utah
(1994)
2.7
1.5
20.9
0.23
Magna, Utah
(1994)
3.1
4.2
16.5
0.47
Telluride, CO
(1986)
3.3
6.8
22.0
0.43
Aspen, CO
(1996)
< 36 mo. (N=4)
4.7
2.6
24.1
.20"
36-84 mo (N=10)
11.2
2.8
66.2
Aspen, CO
(1997)
36-95 mo (N=14)
5.4
2.1
69.8
0.41b
Cincinnati Soil Lead
Abatement Study
(1989-1991)
5.7
10.0
19.4
0.41
Cincinnati Child
Development Study
(1982-1985)
6.4
11.0
13.8
0.56
Trail, B.C.
(1992)
8.9
11.0
20.6
0.28
eN=14; p=.46 ep=0.13
32
TABLE 9.1
Comparison of `96 and `97 Aspen Exposure Data
'N=13
bN=8
`based on homes and children with two consecutive measures (N=8)
33
Geom. Mean
Decline'
Variable units
1996
1997
Aviz.
%v
value
PbB (pg/dl)'
2.8
2.1
-0.7
25
.03
PbH (µg)a
7.1
5.4
-2.1
28
.59
PbD (ppm)b
160
115
-85
43
.04
PbD (µg/M2)b
61
43
-38
47
.12
'N=13
bN=8
`based on homes and children with two consecutive measures (N=8)
33
IV. Summary of Results and Conclusions
1) Blood lead screening reaffirmed the low blood lead levels previously
reported for children at the Smuggler Mountain site (mean blood lead =
2.7 µgldl in 1996 and 2.1 µg/dl in 1997) .
2) Blood lead levels at the Smuggler site are comparable to levels obtained in
a recent national survey (NHANES III) of 2400 children
3) 60 blood samples, collected between 1990 and 1997 yielded a maximum
blood lead level of 8.4 ,ug/dl, i.e. none exceeded the CDC level of concern
4) 13 children sampled in both 1996 and 1997 revealed that the average blood
lead levels are not only low, but stable within individuals (average decline
_ -0.7 µg/dl)
5) 20 percent of 46 exterior dust samples contained lead greater than 1000
ppm and 20 percent of 40 floor dust samples contained lead greater than
500 ppm
6) 43 percent of children tested had unusually high levels (> 10 µg) of lead in
dust recovered from their hands, indicating contact with lead from soil and
dust
7) Homes with lower residential soil lead levels had lower levels of lead in
exterior entry dust and interior dust
8) Although elevated environmental lead levels are present at this site and
children are in contact with this lead, repeated screening of these children
shows no impact of this exposure on blood lead levels of children at the
site.
34
V. References
Agency for Toxic Substances and Disease Registry (1988) . The Nature and Extent of Lead
Poisoning in Children in the United States: A Report to Congress. U.S. Dept. Health and
p Human Services. Doc. No. 99-2966.
Bornschein, R.L., Succop, P., Dietrich, K. N., Clark, C.S., Que Hee, S., and Hammond,
P.B., 1985. The influence of social and environmental factors on dust lead, hand lead and
blood lead levels in young children. Environ. Res. 38:108-118.
Bornschein, R.L., Succop, P.A., Krafft, K.M., Clark, C.S., Peace, B., and Hammond,
P.B., 1986. Exterior surface dust lead, interior house dust lead and childhood lead
exposure in an urban environment. Trace Substances in Environ. Health. 11:322-332.
Bornschein, R.L., Clark, C.S., Grote, J., Peace, B . , Roda, S . , and Succop, P., 1989.
Soil Lead -Blood Lead Relationship in a Former Lead Mining Town. In: Proceedings of
the Lead in Soil: Issues and Guidelines Monograph. Society of Geochemistry and Health.
Bornschein, R., S. Clark, W. Pan, et al., 1990. Midvale community lead study. Final
Report. University of Cincinnati, Department of Environmental Health, Cincinnati, OH.
Bornschein, R.L., Clark, C.S., Pan, W. and Succop, P., 1991. Midvale community lead
study. Soc. Geochem. Health Chem. Spec. Bioavail. 3:149-162.
Bornschein, R.L., Clark, C.S. et al. 1992. Butte -Silver Bow Department of Health and
University, Department of Environmental Health. The 1990 Butte -Silver Bow County
Environmental Health Lead Study Final Report.
Chaney, R.L., 1991. Soil lead chemistry in relation to bioavailability of lead in soil and
dust. In: Proc. Symp. Bioavailability and Dietary Uptake of Lead. R. Cothem and R.W.
Elias (eds.). Research Triangle Park, NC.
Clark, C.S., Bornschein, R.L., Succop, P.A., Que Hee, S., Hammond, P.B., and Peace,
B., 1985. Condition and type of housing as an indicator of potential environmental lead
exposure and pediatric blood lead levels. Environ. Res. 38:46-53.
Karam, H.S., Beck, B.D., Goodman, G., and Steele, M.J., 1993. The Value of Blood
Lead Measurements in Children in Estimating Past, Present, and Future Exposures to
Lead: Application to Risk Management Decisions at Superfund Sites. Society of
Toxicology Annual Meeting, 1993.
35
Mahaffey, K. R., Annest, J. L., Roberts, J. and Murphy, R.S., 1982. National estimates
of blood lead levels: United States 1976-1980 - New England J. Med. 307:573-579.
Mushak, P. (1989) Biological monitoring of lead exposure in children: overview of
selected biokinetic and toxicological issues. In Lead Exposure and Child Development.
v. Smith, M.A., Grant, L.D. and Sors, A. I. (eds.) Kluwer Academic Publishers, Boston,
p. 129-145.
O'Flaherty, E., 1993. Physiologically -based models for bone seeking elements. IV.
Kinetics of lead deposition in humans. Tox. Appl. Pharmacol. 118:16-29.
Pirkle, J.L., Brody, D.J., Gunter, E.W., Kramer, R.A., Paschal, D.C., Flegal, K.M.,
Matte, T.D., 1994. The decline in blood lead levels in the United States. The National
Health and Nutrition Examination Surveys (NHANES). J. Am. Med. Assoc. 272:284-
291.
Preventing Lead Poisoning in Young Children - A statement by the Centers for Disease
Control, 1991. U.S. Dept. Health and Human Services.
Que Hee, S.S., Peace, B., Clark, C.S., Boyle, J.D., Bornschein, R.L., and Hammond,
P.B., 1985. Evolution of efficient methods to sample lead sources such as housedust and
handdust in the homes of children. Environ. Res. 38:77-97.
Schroeder, S.R., Hawk, B., Otto, D.A., Mushak, P. and Hicks, R.E. (1985) Separating
the effects of lead and social factors on I.Q. Environ. Res. 38:144-154.
Smuggler Mountain TAC, 1993. Final Report. Smuggler Mountain Technical Advisory
Committee, Aspen, CO.
Succop, P. A., O'Flaherty, E.J., Bornschein, R. L., Clark, C. S., Krafft, K. M., Hammond,
P. B. and Shukla, R. (1987) A kinetic model for estimating changes in concentration of lead
in the blood of young children. In Lindberg, S.E. and Hutchinson, T.C. (Eds.)
Proceedings of the International Conference: Heavy Metals in the Environment, New
' Orleans, Vol. 2, 289-291.
APPENDIX A
Biological Sample Collection Protocol
Protocol for Blood Collection, Lead Analysis and Quality Control
Whole blood samples will be collected by a trained pediatric phlebotomist for the
analysis of lead and hematocrit. For these analyses, a maximum of 2 ml of blood is
obtained by using venipuncture blood collection techniques. One person is designated
to oversee the collection and record keeping of these samples, make the necessary
preparations for analyses, and be sample custodian.
Sample Collection
Venipuncture samples will be drawn using a 23 gauge butterfly apparatus attached to a
m 6 ml disposable syringe. Blood is immediately dispensed into a K3EDTA containing
pediatric vacutainer tube by insertion of the needle through the top of the tube. The
tube itself is then inverted several times to mix the anticoagulant. All blood sample
collection equipment is prescreened for possible lead contamination.
Sample Analysis
All samples will be analyzed for lead in duplicate using anodic stripping voltommetry
(ASV). Analyses will be conducted at the University of Cincinnati using the method of
Roda et al. 1988. Quality control samples prepared in the Cincinnati Laboratory will
be included in all analytical runs. These samples consist of human blood samples with
a lead content determined by isotope dilution -mass spectrometry, the definitive lead
method. Samples whose duplicate lead values differ by more than 3 [4g/dl will be
reanalyzed. This is expected to occur in less than 2 percent of the samples.
Quality Assurance Plan for Blood Lead Analysis
Details of the quality plan for blood lead analysis including sample custody and specific
routine procedures to assess data precision, accuracy and completeness will be found in
the "Blood Lead Surveillance and Exposure of Young Children to Elevated Soil Lead at
the Smuggler Superfund Site, Aspen, CO Quality Assurance Plan" and "The
Hematology and Environmental Quality Assurance Plan" which are available upon
request. (Also see Appendix I - Field and Laboratory Quality Control Results)
Overview of Protocol for Interviews
Staff involved in interviewing parents will be experienced interviewers who have
` undergone specific training with respect to the questions and information being sought
for this study.
n�
Examples of information obtained during the interview include the following:
1. Parental occupational and education.
2. Recent major renovation at current or prior address (is during last twelve
months) .
3. Frequency of childhood habits such as mouthing behavior and pica.
4. Use of tailings or mine waste as fill material at any site on the residential lot.
5. Lead -related hobbies of occupations.
6. Time spent at day care centers or secondary residences.
7. Time spent at community playgrounds.
Many other questions will be asked and specific questions can be found in Appendix C.
APPENDIX B
Consent Form
UNIVERSITY OF CINCINNATI
CONSENT TO PARTICIPATE INv A RESEARCH STUDY
Childhood Lead Exposure Study at the Smuggler Superfund Site, Aspen, CO.
Institutional Study Number
INVESTIGATOR INFORMATION:
R bell L Bomschein, Ph.D.
Principal Investigator Name
INTRODUCTION
Sponsor Study Number
51'558-0526
Telephone No. 241hr/dav-work,
Before agreeing to participate in this study, it is important that the following explanation of the
proposed procedures be read and understood. It describes the purpose, procedures, benefits, risks
discomforts and precautions of the study. It also describes alternative procedures available and
the right to withdraw from the study at any time. It is important to understand that no guarantee
or assurance can be made as to the results. It is also understood that refusal to participate in this
study will not influence standard treatment for the subject.
I, have been asked to participate in the research study under
the direction, of Sandy M. Roda and the supervision of Dr. R.L. Bomschein. Other professional
persons who work with them as study staff may assist or act for them.
I will be one of approximately 15 subjects to participate in this trial.
PURPOSE:
The purpose of this research study is to determine the amount of lead to which I and my family
are exposed. This will require the measurement of lead in my blood or my child (children),
. My home will be surveyed to determine levels of lead in
soil, dust and water in and near my home. Dust wipe's from the hands of my child (children)
will be taken and also analyzed for lead.
DURATION:
My participation in this study will last for approximately one year.
PROCEDURES:
I have been told that during the course of this study, the following will occur:
A small amount of blood, about two teaspoons will be drawn in order to permit measurements of
lead, hematocrit and blood count. I known that my child may cry for a moment when his/her
finger or arm is pricked to obtain blood for the lead measurement. There tivill be collection of
environmental samples from the inside and outside of my home. Such samples may include
indoor dust, exterior dust, water, handwipe and paint. I understand that my child (children) will
receive a small gift and I will receive a cash payment in the amount of $25 for participating in
the project.
EXCLUSION:
Families living outside the designated study area are excluded from this study.
RISKSIDISCOMFORTS:
I have been told that the study described above may involve the following risks and/or
discomforts and safeguard and or precautions to avoid them:
The risk of simple venipuncture, (sticking needle into vein to draw blood) include: commonly,
the occurrence of discomfort and/or bruise at the site of the puncture; and less commonly,
fainting, the formation of a small blood clot or swelling of the vein and surrounding tissue, and
bleeding from the puncture site. I have also been told that no risks are associated with the survey
of my residence for lead sources. I will be participating in the protocol for approximately one
year. If there is a significant variance from the stated time period, I will be notified. If I am a
woman and I am or should become pregnant, there is no risk to me or my fetus by participating
in the study.
There also may be risks and discomforts which are not yet known.
BENEFITS:
I have been told that the benefits of participating in this study may be:
Notification of blood lead levels as well as environmental lead results. Second, the health
department will be notified if high levels are found so that appropriate actions can be taken. My
family physician will also be notified if my child's blood lead level is greater than 10 Ag/di.
ALTERNATIVES:
There are no alternative procedures or course of treatment that might be available.
- NEW FINDINGS:
I have been told that I will receive any new information during the course of the study
concerning significant treatment findings that may affect my willingness to continue my
participation.
CONFIDENTIALITY:
Every effort will be made to maintain the confidentiality of my study records. The Aspen/Pitkin
Environmental Health Department will be allowed to inspect sections of my medical and
research records related to this study. The data from the study may be published; however, I will
not be identified by name. My identity will remain confidential unless disclosure is required by
law.
FINANCIAL COSTS TO THE SUBJECT:
Funds are not available to cover the costs of any ongoing medical care and I remain responsible
for the cost of nonresearch related care. Tests, procedures or other costs incurred solely for
purposes of research will not be my financial responsibility. If have questions about my
medical bill relative to research participation, I may contact Dr. R.L. Borrmschein (513-558-0526)
COMPENSATION IN CASE OF INJURY:
The University of Cincinnati Medical Center follows a policy of making all decisions concerning
compensation and medical treatment for injuries occurring during or caused by participation in
biomedical or behavioral research on an individual basis. If I believe I have been injured as a
M result of research, I will contact Dr. R.L. Bornschein (513-558-0526) or Mr. Gary Harris,
Chairperson, U.C. Medical Center Institutional Review Board (513-558-5259).
I have been told that in the EVENT OF INJURY resulting from the research procedures in which
I am to participate, no form of compensation is available. Medical treatment may be provided at
my own expense or my health care insurer (e.g., Medicare, Medicaid, Blue Cross/Blue Shield,
etc.) which may or may not provide coverage.
PAYMENTS TO PARTICIPANTS:
INSTITUTIONAL STUDY NUMBER:
SPONSOR STUDY NUMBER:
If requested by the E.P.A. all environmental data collected at my home including my
address may be reported to the appropriate E.P.A. representative.
I HAVE READ THE INFORMATION PROVIDED ABOVE. I VOLUNTARILY AGREE TO
PARTICIPATE IN THIS STUDY. AFTER IT IS SIGNED, I WILL RECEIVE A COPY OF
THIS CONSENT FORM.
Subject Signature Date
CHECK BOX IF VERBAL ASSENT
OBTAINED BY INVESTIGATOR
Legal Representative Parent Date
Signature of Person Obtaining Consent Date
Signature of Investigator Date
Witness Signature Date
APPENDIX C
Data Collection Forms
I Dwelling ID Number
FORM 01 -Housing Survey
Street No. 1 Street Name
,1. Observations: 1 -Structure occupied by residents.
2 --Cannot find address. 3=No structure on lot.
4 --Structure is vacant. 5=Structure not a dwelling.
6=Under const'n. 7=Occup'd no pp. 8-Occup'd nt veri
2. What is the full name of the head of household at this
- (dwelling)?
Family name:
First name:
3. What is the head of
household's phone number?
'4. Interviewee: What is your full name?
- Family name:
First name:
5. Interviewee: What is
your phone number?
-6. Relationship to head of household: El
1=Same, 2=Spouse, 3=Relative, 4=Other
Specify:
8 7. How long has the family lived at this address? EER
R=Refused,
X=Unknown (--Yr M), Z=>999 M
48. Do you rent, own, or lease this (dwelling)?
1 --Own, 2=Rent, 3 --Lease, 4 -Other, 5=Owns
home, not property, R=Refused, X=Unknown
9. Do you live here: 1=All year, 2=Seasonally, 0
3 --Occasionally, R=Refused, X=Unknown
10. Does the owner or manager live in this (building?
house? mobile home park?) 1=owner,
2=Manager, 3=Neither, R=Refused, X=Unknown
Apt No.
11. Please tell me the owner/manager's name?
Family name:
First name:
12. Please tell me the owner/
manager's phone number'?
13. How many children live here who are no more than
72 months of age (up to age six)?
R=Refused, X=Unknown Bom on/after 1111188
14. How many children We here who are older than socE]
and not older than 18 years of age.
15. Are there any pregnant women living here?
1=yes, 2=no, 3=possibly pregnant, 4=more than 1
R=refused, X=unknown.
16. Is there someone living here who is nursing a El
baby? 1=yes, 2=no, R=refused, X=unknown,
4=more than 1
17. Are there any other children brought into this
residence for babysitting on a regular basis?
1=yes, 2=no, R=refused, X=unknown.
18. Is there another family that lives here with you? El
19. Mailing address: P.O. Box
0
20. Mailing address: , Utah 84_ —
21. Year house was constructed:
22. Housing type: 1 mingle family, 2=multi family,
3=mobile home, 4 -double wide, 5 --business,
6=business/residence, 7=other
23. Forms completed:
1=01, 2=01 & 17, 3=01, 03, & 17
4--01, 02, 03, & 17, 5=01, 02, & 17
Call Record
Date Day of week Time Response code and explanation
Response codes: NA=no answer, H=retusea, c;=compierea, Crs=can bat;evi to apP.,
CSA=call back appt.(record appt. date/time), H=hazard to staff (dog,waming signs, hostility), B=phone busy,
INT=need interpreter (specify language)
Date of interview: ` - Interviewers: &
rllesn - -- - --
FORM 03 -Family Questionaire
Dwelling ID Number Family Name First Name
Now I have a few questions to ask about each of the people In the household.
m 1. How many adults, age 18 and older, and children, under 18 years, live here?
Adults, Children, Children, less than 72 months,
age 18 and older. between 6 and 18 years. bom on/after 1111/88.
2. Children up to 72 months, bom on or after 1111188:
No. Last Name First Name Sex Q.O.B. Race Day/Preschool
1-Al.,ti. a Amarin�n i1-:ifkor
' bex: M or r mace. YY-YY111tC, n=na1n11, --v...wq .-. .�... ....._.._-.. _ _
Day Care/Preschool: Enter name of day care or preschool if child attends, otherwise enter N=No# Applicable
3. Pregnant womardwomen:
Employment status: 1=employed full time, 2=employed part time, :s=unempioyea kiempurdr11Y1
4=unemployed homemaker, 5=full time student.
4. Nursing mothers:
No. Last Name First Name D.O.B.
5. Older siblings, 6 to 18 years:
No. Last Name First Name Sex D.O.B.
6. Other adults, 18 years and older.
No. Last Name First Name Sex
eye"
Race I Emp. Sta.
School Name
Emp. Status
Date of interview: Interviewers: & Use other side of form for notes
Phase
y„
P1Vr i..1■ 11 11 1\Ifi \/\/VI1 ■ a I a lVvry
FORM 04 -Recruitment
Tag Number
Dwelling ID Number
Family Name
First Name
Resident Phone
Resident Address
Apt.#
Owner Phone
Owner Address
Owner Name
Contact Phone
Contact Name
Children under six:
# Children (under 6): # Preg. Women: # Nursing Mothers:
Name Birthdate Potty Trained
yes 1 no
yes / no
yes / no
yes 1 no
yes / no
1. Family planning to move within six months: Li 3. Permission from owner to collect exterior Li
samples:
y 1=yes, 2=no, 3 --unknown, 1=yes, 2=no, 3=unknown,
4=other (specify): 4=other (specify):
® 2. Caregiver's response to participation in 4. Caregiver's response to participation in blood
environmental sampling: collection:
1=yes, 2=no, 3 --unknown, 1=yes, 2=no, 3=unknown,
4=other (specify): 4=other (specify):
Call Record
Date Day Time Response Date Day Time Response
Environmental Schedule Record
Date Day Ttme Response Date Day Time Response
Response codes: C -completed, PC= partially completed; H=hazard to staff (dog, warning signs, hostility),
LF=Left flyer, INT=need interpreter (specify language)
Phase
FORM 45 -Interior Dust Sample Collection
.:a
Tag Number
Dwelling ID Number
Family Name
First Name
Samples collected by
Area(sgcm)
CC: N
Custody transfer.
N
Resident Phone
Resident Address
Apt.#
Owner Phone
Owner Address
Owner Name
j N
N
Sample log number - Di
QC Sample log number N
Field Blank log number N
Appointment(s):
DatedTime:
DatetTime:
DatelTme:
N N
N N
N N
Total area sampled " sq cm
Date samples collected
Surface
Samples collected by
Area(sgcm)
CC: N
Custody transfer.
N
From
QC: N
To
NA
Date
I N
Date/Time: Note: Area is calculated by muttiplying number or
grids sampled by 625 sq cm.
Subsample
Locat'n
Surface
# Grids
Area(sgcm)
Child No
1. Entry
N
V2
N
N
NA
2. Most -01 ml
I N
j N
N
NA
Bedroom 1
Bedroom 2
Bedroom 3
Location(room code): 1=Living'room, 2=Kitchen, 3=Dining room, 4=Entry hall, 5=9edroom, 6=Family room, 7=Other
Surface choices: 1=Vinyl, 2 --Carpet, 3=Wood, 4 --Painted, 5 --Concrete, 6=Other
Note: Most -utilized room is the room most -utilized by children <6 years of age.
Project staff followed Protocol SL35C: Signed: Date:
a
Use reverseside for notes.
Pre
weight
Post
weight
Net
weight
V1
N
N
N
V2
N
N
N
V3
I N
j N
N
Location(room code): 1=Living'room, 2=Kitchen, 3=Dining room, 4=Entry hall, 5=9edroom, 6=Family room, 7=Other
Surface choices: 1=Vinyl, 2 --Carpet, 3=Wood, 4 --Painted, 5 --Concrete, 6=Other
Note: Most -utilized room is the room most -utilized by children <6 years of age.
Project staff followed Protocol SL35C: Signed: Date:
a
Use reverseside for notes.
Phase
A01r-14 1 r 1 rUlr %-.Vut4 i i r-nv%JG- 1 Tag Number
FORM 08 -Exterior Dust & Soil Sample Collection
Exterior Dust Samples
Appointment(-,): Street dust samples
Date/Time:
DateMme:
DatelTime:
Exterior entry dust samples
Entry sample log number
-Xi
0 C Sample log number
N
Distance - bldg to street
feet
Subsample number
Entry -1
Entry -2
Entry -3
Entry location
Texture
Surface type
Number of grids
Texture
Total number of grids
Street surface type
Number of grids
Driveway surface type
Total nun-tber of grids
Entry location: 1=Front, 2=Lett siae, j=mignt slue, 4=11ear
Surface type: 1 --Concrete, 2=Asphaft, 3=Brick,
4=Hardpack, 5=Gravel, s=Other, 7=No drive
Texture: 1=Rougtvbroken, 2=Smooffilintact
Sample location descriptions:
Street sample log no.
- Y1
Q C Sample log no.
N
Subsample number
Street -1
Street -2
Sample location
Surface type
Texture
Number of grids
Total number of grids
Street surface type
Driveway surface type
Location: 1=Intersection or onve ana -,trees
2=intersection of walk and street
Exterior dust samples
Date of collection
Samples collected by
Custody transfer
From
To
Date
Entry 1:
Entry 2:
Entry 3:
Street 1:
Street 2:
Project staff followed protocol SL08C: Signed: Date:
Phase
Dwelling ID Number
AW -CIM / t'l 1 MIN LruuV4 1 I i
FORM 10 -Environmental Questionaire
Family Name
First Name
Date of Interview: I Interviewer. I
��* =_: .1 - =1
1. Type of structurelbuilding (rate entire building):
1=Apartments below grade, 2=Apartments on grade,
3=Apartments above grade, 4=Single family, 5 --Single
family with apartments, 6=Duplex, 7= Mobile home,
8=0ther(Specify):
Questions'.
2. Lowest level of dwellingtapartmentlspace occupied ❑
by family:
B=Below grade, 1=0n grade, 2=2nd story,
3 --3rd story, etc.
3. Is there commercial or industrial space in the
building?
1=yes, 2=no, 3=unknown, R=refused
4. Is there a sandbox or play area for children on ❑
the property?
1=general play area, 2=none, 3=unknown,
4=sand box, 5 --play area & sand box
5. Do you have a flower garden at your residence?
Uyes, 2=no, 3=unknown
6. Do you have a vegetable garden at your residence?❑
- 1=yes, 2=no, 3=unknown, 4=not yet, but plan to
7. Do you grow any fruit?
1=yes, 2=no, 3=unknown
S. Do you grow food crops inside or in portable
planters:
Uinside, 2=in planters, 3 --both, 4=neither
Tag Number
9. If inside or in planters, is the soil from: ❑
1=your yard, 2=bagged soil, 3 -combination,
N=not applicable, 4=Other(Specify):
10. Do you grow anything other than beans, ❑
carrots, lettuce, cabbage, or tomatoes?
1=yes, 2=no, N=not applicable.
If yes, what?
11. Of the vegetables grown, which types have
you found difficult to grow?
12. Do you use any old insecticides or herbicides ❑
containing arsenic?
1 --yes, 2=no, 3=unknown, N=not applicable
If yes, list type and brand:
13. Has soil been hauled in and placed on ❑
your garden or yard?
1=yes, 2=no, 3=unknown, N=not applicable
If yes, where did it come from:
14. Does your child play in the garden (e.g.,
while you are working in the garden)?
1=yes, 2=no, 3=unknown, 4 --no garden
1 S. How many days per year does your family
spend away from the Aspen area?
-Continue questions on page -2-
APPENDIX D
Report Forms
Sent to Participating Families
ASPEN/PITKIN COUNTY LEAD EXPOSURE STUDY RESULTS
Family Name
Family ID Number
D., itho .if T.'nvirnnmant/rl .CmmnIP.0 C'nllortod at Your Hobe: LEAD*
Environmental
Community
Community
YOUR LEAD
Sam le Type
Units
Lead Average
Lead Range a
RESULT
Floor Dust
g/m,
0.38
0.14-1.05
Loadinge
Floor Dust Lead
ppm
239
50-757
Concentration
Floor Dust Lead
µg/mz
91
11-410
Loading'
Outside
ppm
300
61-1385
Entry Dust Lead
Concentration
Outside Entry Dust
,ug/m2
120
4-1552
Lead Loading
Street Dust Leadd
ppm
423
106-5601
Concentration
Street Dust
,ugW
320
44-4784
Lead Loading
Soil Lead
Concentration
ppm
540
115-2199
* Summary of Aspen/Pitkin County Lead Study results from 40 homes.
ppm = part per million = amount of lead per gram weight of samples
a g/m2 = grams of dust per square meter area of dust collection
µgW = micrograms of lead per square meter area of dust collection
**** = not collected or not measured
a 90% of the sample results fall within this range.
b Weight of dust collected from one square meter (about one square yard) of floor area.
° Amount of lead detected in the same one square meter sample described above. Current
Housing & Urban Development maximum acceptable level is 100 µg/ff(about 1000 µg/m).
d Dust sample collected at the street curb in front of the house.
10,
�
N
eC
Oo
x
o
ed
z
A
o
U
U
APPENDIX E
Environmental Sample Collection Protocol
I. ORGANIZATION
Environmental samples will be collected by two -person teams. Interior dust, and
administering the environmental questionnaire will be performed by an interior team; exterior
dust and soil samples will be collected by an exterior team.
Interior and exterior environmental sampling teams will visit single-family, detached
residences concurrently. When adverse weather conditions or staff availability prevent a
single visit, the exterior samples will be collected at a different time by the exterior team. In
the case of a multi -family residence, the exterior samples may be collected at a different time
from the interior samples.
Interior and exterior environmental visits will be scheduled by a project staff person.
Environmental visits will be scheduled at specified times based upon the availability of
environmental teams and the convenience and availability of the study participants. A
scheduling log book will be maintained by the staff person in charge of environmental
scheduling.
At the beginning of each day, the list of environmental visits scheduled during the day will be
given to the staff person in charge of environmental team assignments. Preparation of
collection forms and sample containers can then begin for the scheduled visits. Some
flexibility should exist in the scheduling to accommodate unexpected changes in the plans of
the study participants. Even though a telephone call will be made to remind each family of
the scheduled visit, some families may find it impossible, due to unexpected circumstances, to
keep that appointment.
The environmental sampling teams will leave, with their assignments, from the project field
office each day. Prior to lunch, dinner, and at the conclusion of the day, each team will return
to the field office to error check collection forms and transfer custody of environmental
samples to the Project Manager in charge of the field office. That Manager will retain custody
of the samples until they are shipped to the appropriate lab for analysis. At that time, custody
of the samples will be transferred to the analytical -lab personnel who will retain custody
during analysis.
For quality control, 10% of the residences will be re -sampled; duplicates of each type of
sample will be collected at these households. Residences to be treated as QC visits are
identified by random selection, prior to the scheduling of environmental visits. The
monitoring teams will alternate in the collection of the quality control samples.
II. TRAINING ENVIRONMENTAL TECHNICIANS
Two -member teams will be used for the collection of environmental samples and the
recruitment of families into the study.
Environmental technicians will be uniformly trained in the collection of all types of
environmental samples. The training will consist of demonstration, lecture, discussion, and
field practice in the following areas:
" 1. Project orientation, field office organization, data
recording, and safety issues;
2. soil and exterior dust collection;
3. interior dust collection, completion of the environmental questionnaire,
and floor plan drawing; and
III. INTERIOR ENVIRONMENTAL VISITS
Preparation for the interior environmental visit begins at the field office. The environmental
team will be given a daily assignment at the beginning of each day. Once the assignment is
received, the environmental team members will check the accuracy and completeness of the
data on each environmental sample form. The Dwelling ID Number and other idents ing
information should be identical on all the environmental forms: FORM 05, FORM 06,
FORM 08, FORM 09, and FORM 10 (see Appendix D).
After checking these items for accuracy, the environmental team will then calibrate the
sampling pump. The sampling pump should be calibrated to a flow of 2.5 liters per minute.
After the necessary calibration of equipment, the environmental monitoring team should then
use a checklist (Attachments I and II) to make certain all equipment and supplies are packed
and ready for use. At this point, the monitoring team is ready to go into the field.
The interior monitoring visit begins with an introduction to the resident of all members of the
environmental monitoring team or teams. All members should wear appropriate identification.
If the residence to be monitored is a single family, detached residence, both the interior and
exterior teams should be present. All members should be introduced to the residents along
with a short explanation of the monitoring process (see Attachment III for script). After the
introduction and the explanation, the exterior monitoring team will proceed to collect the
exterior dust and soil samples.
The interior monitoring visit can be divided into the following tasks:
1) Sketching a floor plan of the residence.
2) Collection of interior surface dust samples.
3) Administering the environmental questionnaire.
3
The most efficient way to accomplish these visits is to have one team member do the
introduction and administer the environmental questionnaire while the other team member
collects the dust samples, and sketches a floor pian.
At the completion of the collection of the interior samples, a final discussion with the resident
is appropriate. This discussion will include a "thank you" for participating in the project and
allowing the collection of samples. If there is any reason to return at a later time, that should
also be stated to the resident; and, if possible, an appointment should be scheduled. Reasons
for return visits might include the need to collect a particular sample which was unavailable at
the initial visit.
I. INTERIOR SURFACE DUST
The interior surface dust sample will consist of a composite of at least three sub -samples taken
from the following areas in the residence:
1) An area adjacent to the main entrance.
2) A floor area in the room most -utilized by the subject child.
3) A floor area in the subject child's bedroom.
Additional sub -samples may be added to the composite sample. These sub -samples will be
taken from bedrooms occupied by additional subject children.
The main entry sample is collected by placing the template on a carpeted surface immediately
inside of the entry door. If carpeting is not present in this area, the most likely place to find
an adequate surface dust loading would be the area immediately adjacent to the main entry
door. The identification of sample sites from the most frequently occupied room and the
child's bedroom will be determined partly by the floor covering present in those rooms. If the
floor is carpeted, an adequate sample can readily be collected from almost any pathway in the
room. A pathway might consist of an area immediately inside of a doorway into the room or
an obvious pathway from one side of the room to the other. In rooms where there is no
carpeting, the most likely place to find an adequate supply of surface dust would be an area
immediately adjacent to a wall. Very often on floors with hard surfaces, dust will migrate to
the edges; therefore, that is the most likely place to collect the dust.
Interior surface dust is collected by using a personal monitoring pump connected by Nalgene
tubing to a three-piece air monitoring cassette with a 0.8 micron poly cellulose acetate filter.
A collection nozzle is connected to the air monitoring cassette by means of a short piece of
Nalgene tubing. The collection nozzle is a piece of acrylic plastic tubing crimped on one end
to form an opening of approximately 1.3 by 0.1 cm. To facilitate the collection of the interior
dust sample, a template is used. The inside of the template measures 25 cm X 25 cm.
4
The dust sample is collected by placing the template on the identified sampling area. The
pump is then turned on and a visual check is made to make certain that the flow rate is 2.5
liters per minute. The collection apparatus is held at about a 45 degree angle to the surface
(floor) and moved from one side of the template area to the opposite. This sweeping motion in
" the same direction is repeated until the entire area has been "vacuumed" with the collection
attachment. The procedure is repeated in a direction 90 degrees from the initial direction. A
third coverage of the area is then completed in the same direction as the initial coverage. The
rate of movement from one side of the template to the other should be approximately 1.5 - 2
seconds per stroke.
As each sub -sample is collected, its location should be indicated on the floor plan which was
completed earlier. Care should be taken to note the total number of areas sampled. At the
completion of the sample collection, the dust cassette will be removed from the collection
device and the end plugs will be replaced. The dwelling ID number and the sample number
should be written on the side of the cassette with permanent ink. The FORM 05 -Interior Dust
Sampling -Residential work sheet should be completed at the time the dust sample is collected.
As part of the QC program for the Aspen study, two additional interior dust samples will be
collected at the 10% sample of QC residences. The two samples include a wet wipe and high
volume sample (HVS) , co -located with the dust sample collected with the personal monitoring
pump. The wet wipe sample will be collected according to the HUD Clearance Method
(HCM). The HVS sample will collected in a 125 ml bottle attached to a high flow rate, teflon -
coated cyclone, powered by a Dirt Devil vacuum.
2. HANDWIPE SAMPLE COLLECTION
Collection of the hand -dust samples is done at the conclusion of each visit to a residence.
Preliminary data indicate that hand dust equilibrates with a given environment within two
hours. Therefore, the location and activities of the children immediately preceding the testing
are important and should be noted.
The person collecting the hand -dust samples must wear disposable gloves. The person
collecting the hand -dust samples will clean his/her own hands with a disposable wipe from a
separate container of wipes kept for this purpose before touching the gloves or other
equipment. Once the gloves have been put on they also should be cleaned well using
additional clean wipes. For each residence, where one or more child's hands may be sampled,
a field blank is taken. This will be done in the following manner. Six wipes are removed
from the container, handled to simulate wiping a child's hands and then placed in a single bag
and submitted for analysis.
Dust on children's hands is sampled by wiping each hand of the child with three separate
5
commercial Wet -Wipes. All surfaces of the hand, front and back, up to the wrists, are wiped
a thoroughly with each of the three wipes. The wipes from each child are composited in a
single sealable bag for transport to the laboratory. The total quantity of arsenic is reported in
µg arsenic/pair of hands.
The following materials are used to collect hand -dust: a commercially available wipe which
contains a number of ingredients is used (Walgreen's Brand Wet -Wipes). A polypropylene,
zip-loc bag is used to contain the sample. Fisher Scientific Disposable Latex gloves are worn.
IV. EXTERIOR ENVIRONMENTAL VISITS
As with interior environmental visits, preparation for the collection of the exterior dust and
soil samples begins at the field office. The environmental team will be given an assignment
for the morning or the entire day. Once the assignment is received, the environmental team
members will check the accuracy and completeness of the information on the environmental
sampling forms.
After FORM 0$ -Exterior Sampling -Residential has been error checked, the checklist should be
used to make certain all equipment and supplies are packed and ready for use. At this point,
the monitoring team is ready to go into the field.
The exterior monitoring visit to a single family detached residence will begin in the same
manner as the interior monitoring visit. The team members should introduce themselves to the
residents of the property and explain the nature of the environmental sampling. If the team
goes out jointly with an interior monitoring team, then the introduction of both the exterior
and the interior teams will take place at the same time. If the exterior monitoring takes place
at a different time from the interior monitoring, then the monitoring team members should
introduce themselves and explain the nature of the environmental sample collection. As part
of this introduction, the environmental monitoring team should also thank the residents for
participating in the study.
For multi -family dwellings, no introduction is necessary unless there is an on-site manager for
the apartment building or complex. In the case of multi -family dwellings, permission to obtain
samples will have been obtained from the owner or manager prior to sending the
environmental team to the apartment complex. This information should be conveyed to the
on-site manager, if present.
Two types of environmental samples will be collected from the exterior of residences by the
exterior monitoring team. These environmental samples are soil and exterior dust. Either
sample can be collected first, but it is probably more efficient for both team members to work
on the collection of each type of sample.
T
Prior to the collection of any exterior environmental samples, a sketch will be made of the
property and building. This sketch will include such things as the perimeter of the parcel, the
location of sidewalks, the location of the house on the parcel, the location of active gardens,
and the location of bare soil areas. The sketch of the house should be a diagram of the
perimeter of the house, plus the location of entrance doors. The location of exterior dust
samples and soil samples will be indicated on this sketch.
1. EXTERIOR DUST
Two composite exterior dust samples will be collected, an entry sample and a street sample.
The entry sample is a composite sample from two separate areas. The two entry subsamples
will be collected from the front and side or rear entrances to the residence. In the case of
apartment buildings, the samples will be collected from the two entrances most likely used by
the study participants who live in that particular building.
The street composite sample will consist of a subsample collected from the intersection of the
driveway and the street curb and a subsample from the curb area closest to the sidewalk
leading the front entry of the residence. If there is no sidewalk leading from the street to the
front door, the curb area to be sampled should be the area immediately in front of the front
entry to the residence; or alternatively, the curb area closest to the front door.
The entry dust sample is collected by first selecting an area with the heaviest loading of dust
nearest to the door. The area with the heaviest loading is most commonly the intersection of
the first porch step and the sidewalk. Once the heaviest loading has been identified, the
template will be placed over an area that includes that loading and the perimeter of the
template will be drawn on the surface with the carpenter's chalk. The template is removed
and the dust is loosened, if necessary, by means of the stiff bristled brush. Once the material
is loosened, then it can be brushed into a pile within the defined area with the paint brush.
This pile is then scooped up with the scoop and the paint brush and deposited in the
appropriate sample bag. After the bulk of the material is collected in this fashion, the portable
vacuum cleaner is used to vacuum the area defined by the chalk lines.
The first step in using the vacuum is to place a piece of filter material in the collection
cassette. After the filter is in the cassette and the hose is connected to the cassette, and the
collection attachment is connected to the hose, then the vacuum can be turned on. The sample
is collected by passing the collection nozzle across the designated surface area from one side to
the other at the rate of 3 to 4 seconds for each pass along the long axis of the sample area.
Repeated passes are made at the same rate until the entire area is vacuumed one time. A
second collection is made of the same area in a direction 90 degrees to the initial direction.
The rate of movement should be the same. A third collection is made in the same direction as
the initial collection.
7
In some cases where there is an extremely high loading, it may be possible for the filter to
3 clog prior to the completion of the collection of the total sample. Visual checks of the filters
should be made occasionally during the collection process and, if it appears that the filter is
covered with dust, then it should be emptied. This is accomplished by removing the hose and
the collection cassette from the vacuum cleaner and dumping the contents of the cassette into
the sample bag without taking the cassette apart. Tapping on a hard surface will dislodge most
of the material from the filter surface. This should also be dumped into the collection bag.
Both sub -samples should be collected in this fashion.
After they are collected, the hose is cleaned in the following manner. The vacuum cleaner is
allowed to remain running and the hose is lifted into a completely vertical position above the
vacuum. With the vacuum running, the operator taps the side of the hose with the paint brush.
The hose is tapped from it's highest point to it's lowest point a total of three separate times.
This process dislodges most of the dust from the sides of the hose. After this process, the
filter cassette is dumped into the bag. The dust remaining in the collection device is brushed
into the sample collection bag by means of the paint brush. The filter surface is also brushed
into the collection bag. Additionally, the vacuum cleaner is taken apart and the interior of the
top part of the vacuum is brushed with the paint brush into the bowl of the vacuum cleaner.
The bowl is then brushed with the paint brush and any dust remaining in the bowl of the
vacuum cleaner is brushed into the sample bag. Sufficient effort must be expended to collect
and save as much of the dust from the vacuum cleaner and parts as is possible.
Once the surface dust is brushed into the sample collection bag, the vacuum cleaner is cleaned
by utilizing several wet wipes to wipe the interior of the vacuum cleaner bowl and the motor
assembly. On a dry, sunny day, the dampness remaining from using the wet wipe should air
dry rapidly. On a cool, sun -less day, the vacuum bowl may require drying with a paper
towel. Removing the moisture from the vacuum cleaner will prevent dust from the next
sample collection from adhering to the vacuum cleaner.
The final step in the collection of the exterior dust sample is the final check of the data entered
on the sample collection sheets, FORM 08 -Exterior Sampling -Residential. The monitoring
team should make certain that all of the data has been entered onto the sheets. The vacuum
and other equipment are then packed to be transported to the next sampling site.
2. SOIL COLLECTION
Soil samples will be collected with a coring device. The device may be used in either of two
ways. There is a "T" handle which can be attached to the top of the coring device which
allows the operator to push the coring tool into the ground. The coring tool can be twisted as
it is pushed into the ground to allow the cutting edge of the soil corer to cut through roots and
packed earth.
The other method of using the coring tool is to attach a hammer device to the top of the coring
tool. To utilize the coring tool in this manner, the hammer device is first attached to the top
of the coring tool and the tool is placed on the ground where the sample is to be collected.
The hammer is then raised and allowed to fall while it is guided by the operator's hands. This
method may be the most appropriate because of the compacted nature of some of the soils in
the Butte area.
At each residence occupied by a participating family, we will collect a composite soil sample
from the four sides of the residence. Three sub -samples will be collected from each side
where soil is present. The samples will be collected at a distance of three feet from the
exterior wall of the residence. Spacing along a side may depend upon the position of
sidewalks, vegetation, or other obstacles. If there is a sidewalk along an entire side of a
M house, the sample will be collected along the edge of the sidewalk which allows for the least
deviation from the designated three foot line.
These perimeter samples are collected by driving or pushing the coring tool into the ground
approximately 2 to 2 112 inches. The tool is then moved gently from side to side to Ioosen the
plug of earth. The tool is then pulled from the ground and the soil sample is pushed by means
of a pencil or finger so that the upper part of the soil plug lies between the 2 cm marks made
on the coring device. The top 2 cm of the soil sample are then cut from the core by means of
the spatula provided for that purpose. The top 2 cm are then transferred to a blue sample bag.
All 12 sub -samples are collected in this manner.
There are three additional types of samples to be collected from residential parcels. A
composite sample should be collected from bare soil areas in a yard. In addition, a composite
sample from all garden areas should also be collected. These composite samples are collected
in the same manner. There should be a minimum of twelve sub -samples for a garden area or
areas, and twelve sub -samples from any bare area or areas in a yard. For example, if there
are two bare areas in a yard, then a minimum of six sub -samples should be collected from each
bare area. If there are six bare areas in a yard, then twelve sub -samples should be collected,
two from each bare area. The same procedure is to be followed for garden areas.
The final type of soil sample collected will be the sand box or dirt play area sample, if present.
If there is sand in the sand box, a grab sample can be taken. If there is no sand in the sand
box or dirt play area, then twelve core samples will be taken.
Bare -area and sand box samples will be placed in separate white sample bags. Garden samples
will be placed in red sample bags. All sample bags will be labeled with the Dwelling ID
Number using waterproof, permanent ink.
E
EQUIPMENT CHECKLIST FOR INTERIOR RESIDENTIAL VISITS
PERMANENJ EQUIPMENT:
Sample pump with tubing
Stainless steel nozzle with tubing connector
Plastic template
Pens and pencils
Clipboard
Graph paper
Flashlight
Steel file
Watch with second hand or digital readout
PER VISIT HE
Environmental sampling forms
Dust cassettes
Water sample bottles
EQUIPMENT CHECKLIST FOR EXTERIOR RESIDENTIAL VISITS
Clipboard
Graph paper
Pens and pencils
Carpenter's crayon
Template : b" x 24"
Vacuum, hose, and nozzle
Collection cassette and filters
Scoop, paint brush, and brush
Battery pack
Rubber gloves
Dust masks
Wet wipes and paper towels
Trash bag
Soil probe
Stainless steel spatula
PER VISIT Ds
Environmental sampling forms
Bags for exterior dust and soil
INTRODUCTION TO ENVIRONMENTAL VISIT
1. Hello Ms., Mrs., Mr. l I am and this is
(etc.)
2. Thank you for agreeing to participate- in our Health Study. We
are here to collect some environmental samples. and
will collect some soil and dust samples from around the
outside of your house. The soil samples will be small plugs about
1 " x 2". Is there anyplace we cannot collect soil or gardens
where we should be especially careful?
3. and we would like to collect
some dust samples and water samples from inside the house. In
order to collect the water samples, we would like to first run the
water for three minutes and then collect a sample. Thank you.
4. will begin the water test and then make a simple sketch of
the house so that we can locate our samples. Is there anyplace
we cannot go?
5. While is doing that, I would like to ask you some
questions, would you mind?
6. Where does (do)
7. In what room does (do)
sleep?
spend the most time?
8. Which entrance to the house is used most often?
9. Administer the Environmental Questionnaire.
10. Explain urine sample collection and analysis for arsenic.
f',
APPENDIX F
Influence of Altitude on Hematocrit,
Blood Lead and Body Lead Burden
Hematocrits, the percentage of red blood cells per deciliter of whole blood, can vary among
individuals as a function of iron status (iron deficiency results in low hematocrits), age (younger
children have 15-20% lower hematocrits than adults), physiological status (pregnant women have
lower hematocrits than other adults) and elevation (hematocrits in children at high elevations,
such as Aspen, Co., are about 15%-20% higher than children living at sea level).
Since blood lead is usually reported in units of micrograms of lead per deciliter of whole blood
and over ninety eight percent of the lead in whole blood is found in red blood cells, these changes
in hematocrit can influence reported whole blood lead concentrations and distort comparisons
with various reference groups. In order to facilitate comparisons between populations living at
different elevations or different age groups, some adjustment should be made. One approach is
to normalize all results to a common hematocrit e.g. 35% for children and 42% for adults. The
effects of such an adjustment on blood lead concentrations can be seen in Table 1. An alternative
approach involves including hematocrit as a covariate in any regression analysis involving blood
lead. The latter approach has the advantage of providing a quantitative estimate of the effect size
attributable to hematocrit, while at the same time providing improved precision in the parameter
estimates relating environmental lead to blood lead.
Of equal interest and cause for concern is the impact of variation in hematocrits on the validity of
whole blood lead as a marker of lead burden. EPA's "health protective level" of
10 pg/dl is based on studies of child development which relate whole blood lead levels to
developmental processes. The major longitudinal and cross-sectional studies, which form the
basis for EPA and CDC health guidances, were all conducted on cohorts of children living near
sea level with average hematocrits of 35%.
The question arises as to whether 10 µgldl whole blood has the same meaning with respect to
tissue lead concentrations and developmental outcomes at both sea level and at higher elevations.
In an effort to gain some insight into this questions, a physiologically based pharmacokinetic
model (O'Flaherty, 1993) was used to estimate the impact of a change in hematocrit and the
overall size of the red blood cell pool and on the lead content of the major lead pools in the body.
The model was run under two conditions, 35% and 42% hematocrits, with identical lead
exposure inputs, i.e., these model runs were simulating two children with identical exposure
histories but different size red blood cell pools. The results are shown in Table 2 (baseline
exposure) and Table 3 (elevated exposure).
The results of the modelling exercise support the hypothesis that hematocrit (altitude) can
influence blood lead concentrations in the absence of a real difference in tissue lead
concentrations or total body lead burden. For example, comparing two year olds with
hematocrits of 35% versus 42%, the child with the higher hematocrit is predicted to have a blood
lead level which is 20 percent higher while total body lead burdens, and more importantly soft
tissue lead burdens are identical. Note that a two year old child exposed to elevated levels of lead
in soil and dust sufficient to produce a blood lead of 8.2 µg/dl at sea level (hematocrit = 350/6)
would have a blood lead of 9.9 µg/dl in Aspen (hematocrit = 42%). These results from a model
simulation suggest that EPA's "health protective level" of 10 µg/dl is more conservative for
populations living at altitudes significantly above sea level. Soil clean-up levels designed to
prevent exceedences of the 10 pg/dl "health protection level" may be overly conservative. This
issue needs further study.
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Table 2
PBPK Model Inputs
Year 1 Year 2 Year 3
Food
15 µg/day
30 ,cg/day
15 ug/day
Water
5 ppb
5 ppb
5 ppb
Dust
40 ppm
40 ppm
40ppm
Soil
40 ppm
40 ppm
40 ppm
Air
.5 µg/m'
.5 Izg/m3
.5,u
Total Intake
(µg/day)
(mg/yr)
20
7.26
26
9.53
26
9.49
PBPK Model Outputs
Hematocrit (%)
35
42
Age (yrs.)
1
2
3
1
2
3
Blood (µg/dl)
3.2
2.8
2.5
3.8
3.4
3.0
Plasma (µg/dl)
.026
.023
.020
.026
.023
.020
Soft Tissue (µg/dl)
.026
.023
.020
.026
.023
.020
Bone (ppm)
2.5
2.0
1.8
2.5
2.0
1.8
Total Body Burden (mg)
1.2
1.4
1.5
1.2
1.4
1.5
Ref: E. O"Flaherty PBPK Model (See T.A.P.)
Table 3
PBPK Model Estimates of the
Impact of Change in Hematocrit, Brought About by
Differing Altitudes, on Blood Lead Concentration,
Tissue Lead Concentration and Total Body Lead Burden
PBPK Model Inputs
Vaar t Year 2 Year 3
Food
15 ug/day
30 ug/day
15 ug/day
Water
5 ppb
5 ppb
5 ppb
Dust
500 ppm
500 ppm
500 ppm
Soil
500 ppm
500 ppm
500 ppm
Air
.5 ug/m'
.5 ug/m'
.5 ug/m'
Total Intake
(ug/day)
(mg/yr.)
58
21.16
85
31.03
62
22.49
PBPK Model Outputs
Hematocrit (%)
35
42
Age (yrs.)
1
2
3
1
2
3
Blood (ug/dl)
7.6
8.2
6.0
9.0
9.9
7.1
Plasma (ug/dl)
.065
.071
.050
.065
.071
.050
Liver (ppm)
.065
.071
.050
.065
.071
.050
Bone (ppm)
4.8
5.9
4.9
4.8
59
4.9
Total Body Burden (mg)
2.3
4.1
4.1
2.3
4.1
1 4.1
Ref: E. O"Flaherty PBPK Model (See T.A.P.)
Children's (< 72 mo.) Hematocrit in Rocky Mountain Communities
Altitude
N
Arithmetic
S.D.
Min.
Max.
Mean
Leadville
10,300
317
40.8
2.61
32
49
Aspen
8,900
14
41.8
2.51
37
46
Telluride
7,800
94
40.1
2.22
35
45
Butte
203
38.5
2.52
30
51
Midvale
128
37.7
1.79
32
43
APPENDIX G
Individual Data Listing for 1996 and 1997
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APPENDIX H
Project Investigators and Key Personnel
Project Investigators and Key Personnel
Dr. Bob Bornschein
University of Cincinnati
Dr. Paul Succop
University of Cincinnati
Ms. Sandy Roda
Mr. Tom Dunlop
Pitkin Co. Environmental Health Dept.
Dr. Jerry Henningsen
Region VIII Toxicologist, U.S. EPA
Principal Investigator, responsible for
overall scientific leadership and
attainment of study goals.
Co -Investigator responsible for data
management, analysis and collaboration
in data evaluation
Site Manager responsible for
recruitment, clinic operations and
community relations and on site staff
supervision. Also Director of
Hematology and Environmental Analysis
Laboratory, responsible for the analysis
of all biological and environmental
samples and analytical quality control
Responsible for the overall liaison
between the various entities involved in
the study, and assistance in developing
study plan and its final review, and
development of any necessary post -study
follow-up.
EPA Project Toxicologist responsible for
assisting in work plan development and
review of final report.
APPENDIX I
Field and Laboratory Quality Control Results
BLOOD LEAD SURVEILLANCE AND EXPOSURE OF
YOUNG CHILDREN TO ELEVATED SOIL LEAD AT THE
SMUGGLER SUPERFUND SITE; ASPEN, COLORADO
(1997)
FIELD AND LABORATORY
QUALITY CONTROL RESULTS
PREPARED BY: The University of Cincinnati
PREPARED FOR: Pitkin County Environmental Health Department
U.S. Environmental Protection Agency, Region VM
ASPEN, COLORADO
FIELD AND LABORATORY
QUALITY CONTROL RESULTS
The quality of sample collection and analysis can be monitored by evaluating
specific quality control procedures implemented as .part of a project's sampling and
analytical plans. In the Aspen, CO Surveillance and Exposure study various types of
quality control measures were utilized to assess overall quality including the accuracy and
precision of sampling and daily laboratory activities. The following report summarizes the
results of the quality control data generated for the study samples.
Specific protocols were followed for the collection of blood and employed
techniques to ensure quality and avoid contamination of the sample. Blood collection
equipment and supplies were stored and set up in a manner to keep them free from dust
and contaminants. A thorough cleansing of the puncture site was employed to prepare the
patient for sampling. Samples were Kept refrigerated until shipped at the end of the week
of sampling to the University of Cincinnati Hematology & Environmental (H&E)
Laboratory.
The samples were immediately prepared for analysis upon arrival at the laboratory.
Blood samples were analyzed for lead by Anodic Stripping Voltammetry (ASV). All
samples were analyzed in triplicate. The Method Detection Limit for ASV in this
laboratory is 1.0 ug/dl.
A. BLOOD LEAD FIELD QUALITY CONTROL RESULTS
Aliquots of 11 samples were analyzed by the Centers for Disease Control (CDC)
after analysis by the University of Cincinnati H&E Laboratory. Individual results, the
summary statistics, and regression analysis for these samples are listed in Table 1. One of
the samples was actually a field control and the result was not included in the statistics for
the study samples.
Blood samples supplied by CDC were disguised as study samples, intermixed with
the children's samples before shipment, and analyzed by the laboratory blinded as to their
true identity. The CDC target lead concentration of these samples was 4.3 ug/dI. The
analyzed concentrations were 3.6, 4.1, 5.6, 4.9, and 5.1 ug/dl. Table 2 presents the
summary statitics for these results.
A second vacutainer of blood was collected from 8 study participants and sent to
the H&E Laboratory as a blind duplicate. The individual results and descriptive statistics
for the differences between the duplicate sample analysis are shown in Table 3.
B. BLOOD LEAD LABORATORY QUALITY CONTROL RESULTS
_ In the laboratory, different blood samples whose lead values were previously
determined by IDMS, were incorporated into the sample stream of study samples. The
purpose of these samples is to determine the accuracy of the analytical method, ASV,
relative to IDMS and to assess the precision of the method. The presence of the samples
in the analytical run was known to the technician. Results were entered onto control
charts which demonstrated that acceptable performance was achieved. The participant
blood samples were analyzed over a six day period (1018196 - 10114196) and in three
..� different analytical runs.
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Handwipe samples were obtained at two different time points from all children in
the survey and shipped back to Cincinnati for analysis. Three wipes are taken from each
hand of the child and combined as one sample. The samples are digested and analyzed by
flame -atomic absorption spectroscopy (FAAS). Field blanks are collected at each of the
residences and serve to demonstrate the possibility of contamination on field sample
collection. Due to the number of wipes per sample, laboratory blanks determine the
amount of lead actually present in wipe material and thus are subtracted from the total
lead found in each sample following analysis.
a�
There were 21 field blanks collected and analyzed. The average of the blanks was
1.31 ug of lead + 0.5991. One field control fell outside of the three standard deviation
limits of acceptability indicating possible contamination of field samples in that residence
at this time (T -0121 -0000 -1 -H1 -C1 & B 1). All laboratory reagent blanks were <1 ug and
for four analytical sets method blanks were 4.3, 3.2, 3.2, & 3.2 ug. Field controls were
also inserted into samples prior to their shipment to Cincinnati (Table 4).
Soil, Exterior dust, Interior dust, and Street dust samples were collected and then
' shipped to the University of Cincinnati Hematology & Environmental Labs for analysis.
Soil, Exterior and Street dust samples were dried and served to a particle size of 250
..
TABLE
DUPLICATE SAMPLES ANALYZED
BY
UC AND CDC
UC
CDC
(ug/dl)
(ug/dl)
1)
2.8
3.4
2)
2.8
2.4
3)
2.3
2.9
4)
3.9
3.4
5)
<1.0
2.2
6)
1.9
1.7
7)
3.2
2.4
8)
4.8
5.0
9)
5.6
4.6
10)
5.1
4.9
(QC=9.5)
8.7
N 10
10
Mean 3.34 ug/dl
3.29 ug/dl
S.D. 1.49
1.19
Median 3.0
3.2
Minimum <1.0
1.7
Maximum 5.6
5.0
Mean Difference
0.57 ug/dl
Slope
1.113
y -intercept
-0.322
Correlation
0.8897
TABLE 2
UC PERFORMANCE ON BLOOD LEAD
AUDIT FIELD CONTROLS
CDC Assigned
Concentration
4.3 u gld 1
N
5
Mean
4.66 ug/dl
S.D.
0.80
% C.V.
17%
Median
4.9
Minimum
3.6
Maximum
5.6
TABLE 3
BLOOD LEAD FIELD DUPLICATES
TABLE 4
UC PERFORMANCE ON ENVIRONMENTAL
FIELD CONTROLS
SOIL and EXTERIOR
INTERIOR DUST
HANDWIPE
DUST
% Recovery
% Recovery
% Recovery
104
93
122
98
92
117
103
89
117
102
91
114
106
86
106
101
83
106
105
112
98
114
106
119
109
96
101
N
13
6
8
Mean
104%
89%
114%
S.D.
6
4
6
TABLE 5
LABORATORY INTERNAL QUALITY CONTROL
RESULTS
SOIL and EXTERIOR
INTERIOR DUST
HANDWIPE
DUST
NIST % Recovery
NIST % Recovery
20 ug % Recovery
2710 90
2710 91
98
90
90
100
94
91
98
91
94
98
93
2711 94
97
92
96
96
2711 95
96
99
91
97
97
97
2704 87
91
91
92
1648 97
93
98
N
12
12
8
Mean
92%
94%
98%
S.D.
2
3
1
TABLE 6
CO -LOCATED ENVIRONMENTAL SAMPLE
RESULTS
SAMPLE -i
SAMPLE -Z
SOIL (ppm)
819
1040
42
41
105
78
EXTERIOR ENTRY
131
144
DUST (ppm)
245
270
110
101
1591
1921
1853
1538
187
162
EXTERIOR STREET
556
660
DUST (ppm)
250
80
88
9
813
1059
715
696
INTERIOR DUST
479
476
(ppm)
21
53
342
314
491
271
630
669
292
256