THE ENVIRONMENTAL TECHNOLOGY VERIFICATION
PROGRAM
xvEPA
U.S. Environmental Protection Agency
ETV Verification Statement
TECHNOLOGY TYPE: QUALITATIVE SPOT TEST KIT
APPLICATION: LEAD-BASED PAINT DETECTION
TECHNOLOGY NAME: LeadAVERT™ Test Kit
COMPANY: Silver Lake Research
ADDRESS: PO Box 686 PHONE: (626) 359-8441
Monrovia, CA 91017
WEB SITE: http:// www.silverlakeresearch.com
E-MAIL: mgeisberg@silverlakeresearch.com
The U.S. Environmental Protection Agency (EPA) supports the Environmental Technology Verification (ETV)
Program to facilitate the deployment of innovative or improved environmental technologies through
performance verification and dissemination of information. The goal of the ETV Program is to further
environmental protection by accelerating the acceptance and use of improved and cost-effective technologies.
ETV seeks to achieve this goal by providing high-quality, peer-reviewed data on technology performance to
those involved in the design, distribution, financing, permitting, purchase, and use of environmental
technologies. Information and ETV documents are available at www.epa.gov/etv.
ETV works in partnership with recognized standards and testing organizations, with stakeholder groups
(consisting of buyers, vendor organizations, and permitters), and with individual technology developers. The
program evaluates the performance of innovative technologies by developing test plans that are responsive to
the needs of stakeholders, conducting field and laboratory tests (as appropriate), collecting and analyzing data,
and preparing peer-reviewed reports. All evaluations are conducted according to rigorous quality assurance
(QA) protocols to ensure that data of known and adequate quality are generated and that the results are
defensible.
This verification test was conducted under the U.S. EPA through the ETV program. Testing was performed by
Battelle, which served as the verification organization. This verification test was conducted in response to the
call of the Renovation, Repair, and Painting (RRP) rule for an EPA evaluation and recognition program for test
kits that are candidates to meet the false positive and negative goals of this rule. Per the RRP rule, a test kit
should have a demonstrated probability (with 95% confidence) of a false negative response less than or equal to
5% of the time for paint containing lead at or above the regulated level, 1.0 mg/cm2 and a demonstrated
probability (with 95% confidence) of a false positive response less than or equal to 10% of the time for paint
containing lead below the regulated level, 1.0 mg/cm2. Battelle evaluated the performance of qualitative spot
test kits for lead in paint. This verification statement provides a summary of the test results for Silver Lake
Research LeadAVERT™ Test Kit.
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TECHNOLOGY DESCRIPTION
Following is a description of the LeadAVERT™ Test Kit technology, based on information provided by the
vendor. The information provided below was not verified in this test
The LeadAVERT™ Test Kit is an antibody-based test for the detection of lead in paint samples. The test uses
specific monoclonal antibodies that recognize and bind to lead atoms extracted from paint with a weakly acidic,
low-toxicity extraction solution. The antibodies are incorporated in a competitive immunoassay in a lateral-
flow test strip format, so that the entire immunoassay is contained in a small test strip activated by the flow of
sample. Results are read visually as blue lines appearing in the result window of the test strip. The
LeadAVERT™ Test Kit is calibrated to give a "positive" or "negative," relative to the 1 mg/cm2 standard for
lead based paint.
The LeadAVERT™ Test Kit is provided as a 20-test package, and includes all components necessary to run the
test: a reusable stencil to trace a specific area of paint, disposable test vials, an extraction solution in a dropper
bottle, and a container of 20 single-use test strips. Paint is removed from the traced area into the test vial, and
the extraction solution is added to the vial. After 3 minutes, the test strip is placed into the vial, and allowed to
run for 10 minutes. Results are read by comparing the intensity of two blue lines appearing in the "result
window" of the test strip. The entire procedure is completed in less than 15 minutes and requires no power
sources or instrumentation.
The LeadAVERT™ Test Kit package is a container of approximately 5" X 8" X 1.5". Recommended storage is
at room temperature (50-86°F / 10-30°C). The 20-test LeadAVERT™ Test Kit has a suggested retail price of
$39.95 (as of May 2010).
VERIFICATION TEST DESCRIPTION
This verification test of the LeadAVERT™ Test Kit was conducted January through June 2010 at the Battelle
laboratories in Columbus, Ohio. This timeframe included testing of the test kit and also completion of all ICP-
AES and QC analyses.
Qualitative spot test kits for lead in paint were evaluated against a range of lead concentrations in paint on
various substrates using performance evaluation materials (PEMs). PEMs were 3-inch by 3-inch square panels
of wood (pine and poplar), metal, drywall, or plaster that were prepared by Battelle. Each PEM was coated with
either white lead (lead carbonate) or yellow lead (lead chromate) paint. The paint contained lead targeted at 0.3,
0.6, 1.0, 1.4, 2.0, and 6.0 mg/cm2. These lead concentrations were chosen with input from a stakeholder
technical panel based on criteria provided in EPA's lead Renovation, Repair, and Painting (RRP) rule and to
represent potential lead levels in homes. Paint containing no lead (0.0 mg/cm2) was also applied to each
substrate and tested.
Two different layers of paint were applied over the leaded paint. One was a primer designed for adhesion to
linseed oil-based paint and the second coat was a typical interior modern latex paint tinted to one of three
colors: white, red-orange, or grey-black. These colors were chosen by EPA, with input from a stakeholder
technical panel, based on the potential of certain colors to interfere with lead paint test kit operations. The top-
coat paint manufacturers' recommended application thickness was used. Two coats at the recommended
thickness were applied.
The LeadAVERT™ Test Kit for lead paint was operated by a technical and non-technical operator. The
technical operator was a Battelle staff member with laboratory experience who had been trained by the vendor
to operate the test kit. The same technical operator operated this test kit throughout testing. Because this lead
paint test kit is anticipated to be used by certified remodelers, renovators, and painters, it was also evaluated by
a non-technical operator. The non-technical operator was a certified renovator with little to no experience with
lead analysis. The non-technical operator was provided the instruction manual provided by the vendor with the
test kit for training. He then viewed the materials himself to understand how to operate the test kit. He was also
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permitted to ask questions or clarifications of the vendor on the operation of the test kit. This scenario
approximated the training renovators are expected to receive under the RRP rule.
Tests were performed in duplicate on each PEM by each operator, technical and non-technical. Duplicates were
tested in succession by each operator on a given PEM. PEMs were analyzed blindly. Test kit operators were
not made aware of the paint type, lead level, or substrate of the PEM being tested. PEMs used for analysis
were marked with a non-identifying number. PEMs were not tested in any particular order. To determine
whether the substrate material affected the performance of the test kits, two unpainted PEMs of each substrate
were tested using each test kit, in the same manner as all other PEMs (i.e., per the test kit instructions). Three
PEMs at each lead level, substrate, and topcoat color were prepared for use in this test. Thus, a total of 468
painted PEMs were used in the verification test.
To confirm the lead level of each PEM used for testing, paint chip samples from each PEM were analyzed by a
National Lead Laboratory Accreditation Program (NLLAP) recognized laboratory, Schneider Laboratories, Inc.,
using inductively coupled plasma-atomic emission spectrometry (ICP-AES) as the reference method. The paint
chip samples for reference analyses were collected by Battelle according to a Battelle standard operating
procedure (SOP), which was based on ASTM El729. Lead levels determined through the reference analysis
were used for reporting and statistical analyses.
The LeadAVERT™ Test Kit was verified by evaluating the following parameters:
• False positive and negative rates - A false positive response was defined as a positive result when paint
with a lead concentration <0.8 mg/cm2 was not present. A false negative response was defined as a
negative response when paint with a lead concentration >1.2 mg/cm2 was present. Consistent with the
EPA's April 22, 2008 RRP rule, panels with lead levels between 0.8 and 1.0 mg/cm2 were not used in the
false positive analysis, and those with lead levels between 1.0 and 1.2 mg/cm2 were not used in the false
negative analysis.
• Precision- Measured by the reproducibility of responses for replicate samples within a group of PEMs.
Groups of PEMs evaluated for precision included lead concentrations and substrate material. Responses
were considered inconsistent if 25% or more of the replicates differed from the response of the other
samples in the same group of PEMs.
• Sensitivity - The lowest detectable lead level by the test kit. This parameter was identified based on the
detection results across all PEM levels and was determined based on the lowest PEM lead level with
consistent (>75%) positive responses.
• Modeled Probability of Test Kit Response - Logistic regression models were used to determine the
probabilities of positive or negative responses of the test kit at the 95% confidence level, as a function of
lead concentration and other covariates, such as substrate type, lead paint type, operator type, and topcoat
color. In order to account for the uncertainty associated with measurement error of the PEMs, the final
multivariable model for each test kit was subjected to a simulation and extrapolation (SIMEX) analysis.
• Matrix Effects - Covariate adjusted logistic regression models were used to determine whether any of the
PEMs parameters (topcoat color, substrate, operator, or lead paint type) affected the performance of the test
kit. Type III Statistics and comparison of likelihoods from logistic regression models were used to
determine the statistical significance of these factors.
• Operational Factors - Ease of use, operator bias, helpfulness of manuals, technology cost, and
sustainability metrics such as volume and type of waste generated from the use of the test kit, toxicity of the
chemicals used, and energy consumption were noted and summarized.
QA oversight of verification testing was provided by Battelle and EPA. Battelle and EPA QA staff conducted
technical systems audits, and a data quality audit of at least 10% of the test data to ensure that data quality
requirements were met. This verification statement, the full report on which it is based, and the test/QA plan for
this verification test are available at http://www.epa.gov/etv/este.html.
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VERIFICATION RESULTS
False Positive/Negative Rates: Observed false negative rates for the technical operator of the LeadAVERT™
Test Kit on PEMs with confirmed lead levels of > 1.2 mg/cm2 were 37% overall, 71% on yellow lead PEMs,
and 2% on white lead PEMs. Observed false negative rates for the non-technical operator were 56% overall,
96% on yellow lead PEMs, and 15% on white lead PEMs. Substrate and topcoat color did not appear to have
an impact, as these observed false negative rates were similar to the overall rates found for each operator.
The overall observed false positive rate for the LeadAVERT™ Test Kit on PEMs with confirmed lead levels of
< 0.8 mg/cm2 was 22% for the technical operator and 12% for the non-technical operator. Evaluation of white
lead PEMs produced the highest observed false positive rate for both operators.
Precision: Across both operators and all substrates and lead paint type, responses from the LeadAVERT™
Test Kit were inconsistent across all lead levels except 0.0 and 0.3 mg/cm2. These overall inconsistencies were
influenced by the lack of positive responses for most yellow lead PEMs.
Results from the LeadAVERT™ Test Kit indicated 100% precision on PEMs that contained no lead and 90%
precision on PEMs that contained yellow lead. The precision for yellow lead panels is indicative of the lack of
positive responses across most of these type of PEMs, including those with detectable levels of lead. The
technical operator provided results with 96% precision for the white lead PEMs, but those for the non-technical
operator were 61%.
Sensitivity: Across all lead paint types and operators, the LeadAVERT™ Test Kit did not generate consistent
positive results at any lead level. When sensitivity was evaluated by operator type, the lowest lead level for
which consistently positive results were found was 1.4 mg/cm2 on white lead PEMs, but no consistently positive
results were obtained at any lead level for yellow lead panels. Consistently positive responses were found at the
0.6 mg/cm2 lead level for the technical operator on white lead PEMs. The 0.6 mg/cm2 lead level is actually
below the lead level that should produce a positive response, so sensitivity as measured through positive
responses is actually indicating false positive associations in this case. Otherwise, the LeadAVERT™ Test Kit
as operated by the technical operator did not generate any consistently positive responses for yellow lead PEMs,
and the overall sensitivity for the LeadAVERT™ Test Kit as used by the technical operator was 6.0 mg/cm2,
above the desired 1.0 mg/cm2 lead level.
Modeled Probability of Test Kit Response: Based on the lower bound estimates of the modeled probability of
the LeadAVERT™ Test Kit, the results indicate that a false negative rate of <5% was not obtained at 1.2
mg/cm2.
Based on the upper bound estimates of the modeled probability of the LeadAVERT™ Test Kit, the technology
met the false positive criterion (<10%) at 0.8 mg/cm2 for yellow lead. Thus, a false positive rate of less than
10% would only be expected to be achieved by both the technical and non-technical operator on all substrates
with yellow lead. The lowest false positive rates (from 1.7% to 2.7%) would be expected when the non-
technical operator was using the LeadAVERT™ Test Kit to evaluate yellow lead paint on wood, drywall,
plaster, and metal.
Matrix Effect: After controlling for the significant covariates, the likelihood of a positive test result is
positively and significantly associated with: higher lead levels, testing by a technical operator, metal and plaster
substrates, and white lead. It is not significantly and positively associated with testing by a non-technical
operator, wood and drywall substrates, and yellow lead.
Operational Factors: Both the technical and non-technical operator found the LeadAVERT™ Test Kit
instructions to be clear, informative, and easy to follow. The solutions used for different steps were easily
identifiable within the kit and the storage conditions of the reagents were readily marked. All reagents came
prepared and ready to use.
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The LeadAVERT™ Test Kit came in packs of 20 strips. Each kit included a stencil, 20 square test vials, one
bottle of extraction solution, and one container of 20 test strips. The user was expected to supply a pencil (for
tracing the stencil), tape (for adhering the vial to the sampling area), a utility knife (for cutting to paint from the
sampling area), and a timer or stopwatch (for tracking the time periods noted in the instructions).
One test strip, one vial, and 11 drops of extraction solution are produced as waste for a single test.
Interpretation of the test strips for the LeadAVERT™ Test Kit was sometimes difficult. It was difficult to
discern if the two lines were equal or if one line was darker than the other in some samples. In all samples, it
was up to the discretion of the user to determine the darkness of lines on the test strip.
The LeadAVERT™ Test Kit was quick and easy to operate. Operation of the test kit took approximately 15
minutes for one sample for both the technical and non-technical operator. No power supply was needed for the
operation of the test kit.
Signed by: Sally Gutierrez - December 03, 2010
Sally Gutierrez Date
Director
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
NOTICE: ETV verifications are based on an evaluation of technology performance under specific,
predetermined criteria and the appropriate quality assurance procedures. EPA and Battelle make no
expressed or implied warranties as to the performance of the technology and do not certify that a technology
will always operate as verified. The end user is solely responsible for complying with any and all applicable
federal, state, and local requirements. Mention of commercial product names does not imply endorsement.
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