U.S. Environmental Protection Agency
nmental Technology Verification
ETV
Portable Technologies for Measuring Lead in Dust
The U.S. EPA Environmental Technology Verification
(ETV) Program's Site Characterization and Monitoring
Technologies (SCMT) Pilot, which was operated by Oak
Ridge National Laboratory (ORNL) under an interagency
agreement with EPA, and was an element of the Advanced
Monitoring Systems (AMS) Center, has verified the per-
formance of six field screening analyzers for lead in dust.1
A technical panel of experts in lead testing, which
included representation from the U.S. Department of
Housing and Urban Development (HUD), National
Institute for Occupational Safety and Health, National
Institute of Standards and Technology, American
Industrial Hygiene Association, Massachusetts Childhood
Lead Poisoning and Prevention Program, and several EPA
offices, including the Office of Pollution Prevention and
Toxics, assisted with the design of the verification test and
the reporting of results. These portable analyzers allow
quick identification of lead levels in dust onsite and enable
the user to react to potential health risks in a timely
manner.
Technology Description and Verification Testing
The technologies verified by the ETV Program are
portable and designed to be used to analyze dust samples
in the field. The verified technologies use either X-ray
fluorescence (XRF) or anodic stripping voltammetry
(ASV). XRF allows for non-destructive analysis of a
sample. This technique uses a radioisotope source or X-ray
tube to excite lead atoms in the sample. The atoms, in turn,
emit characteristic X-rays that are detected, quantified, and
identified by the spectrometer. ASV is a destructive
analysis method. A test sample is contacted with acid to
bring lead into solution. The solution is subsequently
mixed with a buffer salt solution. Lead in the solution is
plated on and then stripped off an electrode. Each metal
will strip from the electrode at a different potential,
allowing for its identification, while the amount of current
produced is quantified and correlated to sample
concentration. Table 1 identifies the six ETV-verified
technologies and the technique used by each.
A primary objective of the ETV test was to assess whether
the participating
field portable
technologies
produced results
that were
comparable to
National Lead
Laboratory
Accreditation
Program (NLLAP)
recognized data.
During verification
testing, 160 dust
wipe samples were
A verified lead in dust analyzer analyzed. These
Environmental, Health, and Regulatory
Background of Lead at a Glance
Lead is a highly toxic metal that was used for
many years in products (e.g., as a pigment in
paint products) found in and around homes.
Lead may cause a range of health effects, such
as behavioral problems and learning
disabilities, and, at high levels of exposure, can
result in brain damage or death. Research
suggests mat the primary sources of lead
exposure for most children are deteriorating
lead-based paint, lead contaminated dust, and
lead contaminated residential soil. Children six
years old and under are most at risk because
their bodies are growing quickly.
The Centers for Disease Control and
Prevention have determined in children
elevated blood lead levels (BLLs) of 10
micrograms per deciliter or higher are
associated with adverse health effects. To
address the hazards of lead poisoning, the U.S.
Consumer Product Safety Commission banned
lead-based paint in 1978. However, homes built
prior to 1978 are still in use and may have
interior or exterior paint containing lead. In
1992, the U.S. Congress enacted the
Residential Lead-Based Paint Hazard
Reduction Act. Under this act, EPA and other
federal agencies such as HUD established
numerical standards for hazardous levels of
lead in dust for pre-1978 housing and child-
occupied facilities, required disclosure of
known lead-based paint and lead-based paint
hazards to buyers and tenants, and provided
grants for low-income families who occupy
lead-based-paint hazards in private housing.
The grants include clean-up, control, testing,
awareness, and training.
wipes contained between 2 and 1,500 micrograms
of lead per dust wipe, which is representative of
levels found in house dust wipe samples collected
using ASTM methods. The ETV Program
evaluated the technologies on the following
performance parameters: precision, accuracy,
comparability to NLLAP recognized laboratory
results, detectable blanks, false positive results,
false negative results and other parameters. Table
2 summarizes some of the performance data for
the individual verified technologies. Additional
information is available in the full verification
reports and verification summary statements which
can be found at http://www .epa.gov/etv/
verifications/vcenterl -22.html.
The ETV Program operates largely as a public-private partnership through competitive cooperative agreements with non-profit research institutes. The
program provides objective quahty-assured data on the performance of commercial-ready technologies. Verification does not imply product approval or
effectiveness. ETV does not endorse the purchase or sale of any products and services mentioned in this document.
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Table 1 . Verified Portable Technologies for Measuring Lead in Dust
Vendor
KeyMaster Technologies
Monitoring Technologies International
Thermo Electron Corporation,
NITON Analyzers Business Unit
(Formerly NITON LLC)
Palintest
Verified Technology
X-Ray Fluorescence Instrument Pb-Test
PDV 5000 Trace Element Analyzer
X-Ray Fluorescence Spectrum Analyzer XLt 700 Series
X-Ray Fluorescence Spectrum Analyzer XL 700 Series
X-Ray Fluorescence Spectrum Analyzer XL 300 Series
Scanning Analyzer SA-5000 System
Technology Type
XRF
ASV
XRF
XRF
XRF
ASV
Selected Outcomes of Verified Portable Technologies for Measuring Lead in Dust
• Based on a hypothetical projection of 25% market penetration, the ETV-verified portable
measurement technologies could be deployed at up to approximately 9.5 million housing units out of an
estimated potential market of 38 million (Jacobs et al. 2002) that were built before 1978 to:
- screen for lead hazards (e.g., as part of a lead hazard screen) and assess potential risks (e.g., during a risk
assessment).
- temporarily clear residences for occupation following abatement or lead hazard control activities
followed by final clearance based on fixed site laboratory analysis.
- develop a focused and cost-effective sampling and analysis strategy provided the technology is used bv a
portable laboratory or field service and measurement organization that has been accredited by NLLAP1.
• The information provided by these technologies can assist in the reduction of lead exposure, with
associated human health and economic benefits, particularly for children. These technologies can be used to
investigate instances of elevated BLLs in children.
• ETV verification also can potentially increase acceptance and use of the portable measurement
technologies. ETV reports have been cited as a resource for promoting the use of the lead monitoring
technologies such as the XRF instruments for residential lead soil and dust testing. Previous ETV
verifications of similar technologies have assisted in the development of approved EPA methods for using
field portable measurement technologies.
1 The limitations to this assumption is explained on p. 48 of the ETV Case Studies: Demonstrating Program Outcomes. EPA/600/R-06/001. January 2006
Table 2. Performance of Verified Portable Technologies for Measuring Lead in Dust
Vendor3
A
B
C
D
E
F
Average
relative
accuracyb,%
168 to 189
88 to 93
91 to 97
107 to 119
80 to 91
97 to 101
Average
relative
precisionc,%
15 to 18
21 to 22
7 to 8
8
5 to 8
11
Rate of
false
positives
26 of 50
7 of 41
Oof 42
27 of 46
Oof 50
9 of 49
Rate of false
negatives
15 of 50
19 of 57
36 of 58
4 of 54
39 of 50
18 of 51
Comparability11
slope
0.662 to 1.060
0.885 to 1.074
0.849 to 0.936
1.1 12 to 1.206
0.839 to 0.926
0.977 to 0.995
intercept
66 to 121
-14.345 to 15.633
7.495 to 11. 262
-3.29 to 13.283
5.539 to 6.506
3.076 to 4.775
r2
0.967 to 0.989
0.988 to 0.999
0.999
0.999
0.995 to 1.000
0.999
a Because the ETV Program does not compare technologies, the performance results shown in this table do not identify the technologies
associated with each result and are not in the same order as the list of technologies in Table 1.
b A result of 100% indicates perfect accuracy relative to the tested lead concentration.
c A result of 0% indicates perfect precision.
d Comparability of the technologies to the standard test method was evaluated using linear regression analysis.
References:
U.S. EPA, ETV Case Studies: Demonstrating Program Outcomes. EPA/600/
R-06/001. January 2006 (primary source), http://www.epa.gov/etv/pdfs/
pubhcations/600r06001/600r06001pv.pdf.
U.S. EPA, ETV. http://www.epa.gov/etv.
U.S. EPA, Lead in Paint, Dust, and Soil. 06 Feb. 2007. http://www.epa.gov/
lead/index.html.
Jacobs DE, Clickner RP, Zhou JY, Viet SM, Marker DA, Rogers JW, et al.
2002. The Prevalence of Lead-Based Paint Hazards in U.S. housing. Environ-
mental Health Perspectives 110(10):A599-A606. October.
ETV Advanced Monitoring
Systems Center
Robert Fuerst, EPA,
fuerst. robert@epa. gov
Tel: (919) 541-2220
Amy Dindal, Battelle
dindala@battelle. org
Tel: (561)422-0113
EPA/600/S-07/028
August 2007
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