September 2006
Environmental Technology
Verification Report
ABRAXIS LLC
ORGANOPHOSPHATE/CARBAMATE SCREEN KIT
Prepared by
Battelle
Battelle
I he Business of Innovation
Under a cooperative agreement with
V8* trr\ U.S. Environmental Protection Agency
ET1/ET1/ET1/
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September 2006
Environmental Technology Verification
Report
ETV Advanced Monitoring Systems Center
Abraxis LLC
ORGANOPHOSPHATE/CARBAMATE SCREEN KIT
by
Stephanie Buehler
Raj Mangaraj
Amy Dindal
Zachary Willenberg
Karen Riggs
Battelle
Columbus, Ohio 43201
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Notice
The U.S. Environmental Protection Agency (EPA), through its Office of Research and
Development, has financially supported and collaborated in the extramural program described
here. This document has been peer reviewed by the Agency. Mention of trade names or
commercial products does not constitute endorsement or recommendation by the EPA for use.
11
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Foreword
The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the
nation's air, water, and land resources. Under a mandate of national environmental laws, the
Agency strives to formulate and implement actions leading to a compatible balance between
human activities and the ability of natural systems to support and nurture life. To meet this
mandate, the EPA's Office of Research and Development provides data and science support that
can be used to solve environmental problems and to build the scientific knowledge base needed
to manage our ecological resources wisely, to understand how pollutants affect our health, and to
prevent or reduce environmental risks.
The Environmental Technology Verification (ETV) Program has been established by the EPA to
verify the performance characteristics of innovative environmental technology across all media
and to report this objective information to permitters, buyers, and users of the technology, thus
substantially accelerating the entrance of new environmental technologies into the marketplace.
Verification organizations oversee and report verification activities based on testing and quality
assurance protocols developed with input from major stakeholders and customer groups
associated with the technology area. ETV consists of six environmental technology centers.
Information about each of these centers can be found on the Internet at http://www.epa.gov/etv/.
Effective verifications of monitoring technologies are needed to assess environmental quality
and to supply cost and performance data to select the most appropriate technology for that
assessment. Under a cooperative agreement, Battelle has received EPA funding to plan,
coordinate, and conduct such verification tests for "Advanced Monitoring Systems for Air,
Water, and Soil" and report the results to the community at large. Information concerning this
specific environmental technology area can be found on the Internet at http://www.epa.gov/
etv/centers/centerl .html.
in
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Acknowledgments
The authors wish to acknowledge the support of all those who helped plan and conduct the
verification test, analyze the data, and prepare this report. Many thanks go to Battelle's
Hazardous Materials Research Center for providing the facilities for and personnel capable of
working with chemical warfare agents. We sincerely appreciate the contribution of drinking
water samples from the Metropolitan Water District of Southern California (Paul Rochelle and
Melinda Stalvey), the New York Department of Environmental Protection (Virginia Murray),
and Orange County Utilities, Orlando, Florida (Theresa Slifko and Liza Robles). We would also
like to thank Armah de la Cruz (U.S. EPA, National Exposure Research Laboratory), Ricardo
DeLeon (Metropolitan Water District of Southern California), Yves Mikol (New York City
Department of Environmental Protection), and Helen Schurz Rogers (Centers for Disease
Control and Prevention National Center for Environmental Health) for their careful review of the
test/QA plan and this verification report.
IV
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Contents
Page
Notice ii
Foreword iii
Acknowledgments iv
List of Abbreviations vii
Chapter 1 Background 1
Chapter 2 Technology Description 2
Chapter 3 Test Design 4
3.1 Introduction 4
3.2 Test Samples 4
3.2.1 PT Samples 5
3.2.2 DW Samples 6
3.2.3 QC Samples 7
3.2.4 Operational Factors 7
3.3 Verification Schedule 8
3.4 Test Procedure 8
3.4.1 Test Sample Preparation and Storage 8
3.4.2 Test Sample Analysis Procedure 8
3.4.3 Drinking Water Characterization 9
Chapter 4 Quality Assurance/Quality Control 11
4.1 Sample Chain-of Custody Procedures 11
4.2 QC Samples 11
4.3 Equipment/Calibration 13
4.4 Characterization of Stock Solutions 13
4.5 Audits 14
4.5.1 Performance Evaluation Audit 14
4.5.2 Technical Systems Audit 15
4.5.3 Audit of Data Quality 15
4.6 QA/QC Reporting 15
4.7 Data Review 15
Chapter 5 Statistical Methods and Reported Parameters 17
5.1 Accuracy 17
5.2 False Positive/False Negative Rates 17
5.3 Precision 18
5.4 Potential Matrix and Interferent Effects 18
5.5 Operational Factors 18
Chapter 6 Test Results 19
6.1 Accuracy 20
6.2 False Positive/False Negative Rates 20
6.3 Precision 28
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6.4 Potential Matrix and Interferent Effects 28
6.4.1 Interferent PT Samples 28
6.4.2 DW Samples 29
6.5 Operational Factors 29
6.5.1 Technical Operator 29
6.5.2 Non-Technical Operator 30
Chapter 7 Performance Summary 32
Chapters References 39
Figures
Figure 2-1. Abraxis LLC, Organophosphate/Carbamate Screen Kit 2
Figure 6-1. Side View of PPE Worn by Non-Technical Operator 31
Figure 6-2. Testing of the OP/C Screen Kit with the Non-Technical Operator Wearing PPE 31
Tables
Table 3-1. Lethal Dose of Target Contaminants 5
Table 3-2. Performance Test Samples 6
Table 3-3. Drinking Water Samples 7
Table 3-4. ATEL Water Quality Characterization of Drinking Water Samples 10
Table 4-1. Reference Methods for Target Contaminants and Interferents 12
Table 4-2. Performance Evaluation Samples and Percent Difference 15
Table 4-3. Summary of Data Recording Process 16
Table 6-1. Contaminant-Only PT Sample Results 21
Table 6-2a. VX False Positive/Negative Results 22
Table 6-2b. GB False Positive/Negative Results 23
Table 6-2c. GD False Positive/Negative Results 24
Table 6-2d. Aldicarb False Positive/Negative Results 25
Table 6-2e. Dicrotophos False Positive/Negative Results 26
Table 7-1. VX Summary Table 33
Table 7-2. GB Summary Table 34
Table 7-3. GD Summary Table 35
Table 7-4. Aldicarb Summary Table 36
Table 7-5. Dicrotophos Summary Table 37
vi
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List of Abbreviations
ACh-E
AMS
ASTM
ATC
ATEL
Ca
DI
DPD
DTNB
DW
ECD
EPA
ETV
GB
GC
GD
HAZWOPER
HOPE
HMRC
ICP
ID
kg
L
LC
LD50
LOD
LRB
MB
Mg
mg/L
mL
MS
acetyl cholinesterase
Advanced Monitoring Systems
American Society for Testing and Materials
acetylthiocholine
Aqua Tech Environmental Laboratories, Inc.
calcium
deionized
diethyl-p-phenylene diamine
5,5'-dithio-bis(2-nitrobenzoic acid)
drinking water
electron capture detection
U.S. Environmental Protection Agency
Environmental Technology Verification
sarin
gas chromatography
soman
Hazardous Waste Operations and Emergency Response
high density polyethylene
Hazardous Materials Research Facility
inductively coupled plasma
identification
kilogram
liter
liquid chromatography
lethal dose for half of test subjects
limit of detection
laboratory record book
method blank
magnesium
milligram per liter
milliliter
mass spectrometry
vn
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|j,g/L microgram per liter
uMHO micromho
NaOH sodium hydroxide
NDR negative differential resistance
ng nanogram
NTU nephelometric turbidity unit
OP organophosphate
OP/C organophosphate/carbamate
PE performance evaluation
PPE personal protective equipment
PT performance test
QA quality assurance
QC quality control
QMP quality management plan
RPD relative percent difference
SCBA self-contained breathing apparatus
SM standard method
SOP standard operating procedure
ISA technical systems audit
Vlll
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Chapter 1
Background
The U.S. Environmental Protection Agency (EPA) supports the Environmental Technology
Verification (ETV) Program to facilitate the deployment of innovative 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.
ETV works in partnership with recognized testing organizations; with stakeholder groups
consisting of buyers, vendor organizations, and permitters; and with the full participation of
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 or laboratory tests (as appropriate), collecting and analyzing data, and preparing
peer-reviewed reports. All evaluations are conducted in accordance with rigorous quality
assurance (QA) protocols to ensure that data of known and adequate quality are generated and
that the results are defensible.
The EPA's National Exposure Research Laboratory and its verification organization partner,
Battelle, operate the Advanced Monitoring Systems (AMS) Center under ETV. The AMS Center
recently evaluated the performance of the Abraxis LLC, Organophosphate/Carbamate (OP/C)
Screen Kit in detecting chemical agents, carbamate pesticides, and organophosphate pesticides in
drinking water. Enzymatic test kits were identified as a priority technology category for
verification through the AMS Center stakeholder process.
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Chapter 2
Technology Description
The objective of the ETV AMS Center is to verify the performance characteristics of
environmental monitoring technologies for air, water, and soil. This verification report provides
results for testing the OP/C Screen Kit. Following is a description of the OP/C Screen Kit, based
on information provided by the vendor. The information provided below was not verified in this
test.
The Organophosphate/Carbamate Screen Kit is an in vitro enzymatic test used to detect a wide
range of organophosphates (including thiophosphate) and carbamates in water and other
environmental matrices. The test is a qualitative, colorimetric assay (modification of the Ellman
method) for the detection of organophosphates and carbamates that is based on their inhibition of
the enzyme acetyl cholinesterase (ACh-E). ACh-E hydrolyzes acetylthiocholine (ATC), which
reacts with 5, 5'- dithio-bis(2-nitrobenzoic acid) (DTNB) to produce a yellow color that is read at
405 or 450 nanometers. Depending on their concentrations, OP or C compounds present in a
sample will inhibit ACh-E and therefore color formation will be reduced or absent.
The OP/C Screen Kit is supplied with
freeze-dried ACh-E and ATC in dropper
bottles. Both are reconstituted with
diluents supplied in the OP/C Screen Kit.
The oxidizer solution is prepared by taking
200 microliters (|iL) of the oxidizer and
placing it into the dropper bottle
containing the oxidizer diluent. All other
reagents are ready to use and supplied in
color-coded dropper bottles. A 5-minute
incubation follows the oxidation of
controls and samples. After adding
neutralizer and Ach-E, an incubation of 15
to 30 minutes is required; and after adding
the ATC (substrate) and DTNB
(chromagen), a 30-minute incubation is
required. Color development is curtailed
by adding stop solution. The tubes are
read in a colorimeter at 405 or 450 nanometers. Not supplied is a colorimeter capable of
reading 405 or 450 nanometers; however, samples can also be read by visually comparing the
sample to the negative control.
Figure 2-1. Abraxis LLC, Organophosphate/
Carbamate Screen Kit System
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The OP/C Screen Kit contains 20 tubes with assay buffer, two test tubes (one to be used for the
negative control and ATC diluent and the other for the ACh-E diluent). Dropper bottles with
color-coded caps contain the freeze dried ATC and Ach-E and ready-to-use solutions of oxidizer
diluent, neutralizer, chromagen (DTNB), and stopper solution. Also included are two 4-milliliter
(mL) amber vials that contain the oxidizer and positive control (5 parts per million diazinon in
deionized water). There are two 3-mL transfer pipettes and 22 exact-volume 100-jiL disposable
pipettes included in the kit. The assay incubations are performed at 70±20° F (21 ±7° C).
The box containing the OP/C Screen Kit is 17 by 10.5 by 9.5 centimeters and can be used as a
work station. The price of the OP/C Screening Kit (20 tests) is $180, not including the
colorimeter.
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Chapter 3
Test Design
3.1 Introduction
Enzymatic test kits, generally designed to be handheld and portable, detect the presence of
chemical agents, carbamate pesticides, and/or OP pesticides by relying on the reaction of the
cholinesterase enzyme. Under normal conditions, the enzyme reacts as expected with other
chemicals present in the test kit. The activity of the enzyme is inhibited, however, by chemical
agents, carbamate pesticides, and OP pesticides. The effects of this inhibition will then generally
lead to a color change, indicating the presence or absence of these compounds.
The objective of this verification test was to evaluate the ability of the OP/C Screen Kit to detect
chemical agents, carbamate pesticides, and OP pesticides in drinking water. This verification test
assessed the performance of the OP/C Screen Kit relative to
• Accuracy
• False positive and negative rates
• Precision
• Potential matrix and interference effects
• Operational factors (operator observations, ease of use, and sample throughput).
3.2 Test Samples
This test evaluated the ability of the OP/C Screen Kit to detect VX, sarin (GB), and soman (GD)
(chemical agents); aldicarb (carbamate pesticide); and dicrotophos (OP pesticide) in performance
test (PT) and drinking water (DW) samples. Quality Control (QC) samples were also included as
part of the test matrix to ensure the integrity of the test. Contaminants were tested individually,
and stock solutions of each contaminant were prepared separately in American Society for
Testing and Materials (ASTM) Type II deionized (DI) water. Samples were prepared in the
appropriate matrix using these stock solutions and analyzed on the same day. To minimize the
loss of analytes to hydrolysis, contaminant stock solutions prepared in DI water were made on a
daily basis. Chemical agent stock solutions were prepared twice daily, once in the morning and
once in the afternoon. Aliquots of each stock solution were diluted to the appropriate
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concentration using volumetric glassware and volumetric or calibrated pipettes. In some cases,
reference solutions were prepared in ASTM Type IIDI water using the stock solutions used to
prepare the test samples. In other cases, the actual stock solutions were submitted for
concentration confirmation by the respective reference analysis (Table 4-1). Aqua Tech
Environmental Laboratories, Inc. (ATEL) of Marion, OH performed the physiochemical
characterization for each type of DW sample along with reference analyses of the interferent
solutions. All other reference analyses were performed at Battelle.
3.2.1 PT Samples
PT samples were prepared separately in ASTM Type II DI water for each contaminant. The first
type of PT samples consisted of ASTM Type II DI water spiked with the contaminant at five
different concentrations: the lethal dose concentration given in Table 3-1 for each contaminant,
along with dilutions at approximately 10, 100, 1,000, and 10,000 times less than the lethal dose.
The contaminants were added individually to each spiked sample. The lethal dose of each
contaminant was determined by calculating the concentration at which 250 milliliters (mL) of
water is likely to cause the death of a 70-kilogram (kg) person based on human oral LDso (lethal
dose for half of the test subjects) data.(u) Human oral LD50 data were not available for aldicarb,
so rat oral LD50 data were used instead.(3) Each concentration level for the PT samples was
analyzed in triplicate.
In addition to the contaminant-only PT samples described above, a second type of PT sample
was a potential interferent sample. Three replicates of each interferent PT sample were analyzed
to determine the susceptibility of the OP/C Screen Kit to these commonly found interferents in
DW. One interferent PT sample contained calcium (Ca) and magnesium (Mg) from carbonates
spiked into ASTM Type II DI water, and the other contained humic and fulvic acids isolated
from the Elliot River (obtained from the International Humic Substances Society) spiked into
ASTM Type II DI water. Each interferent mixture was prepared at two concentration levels: near
the upper limit of what would be expected in drinking water (250 milligrams/liter (mg/L) total
concentration for Ca and Mg, 5 mg/L total concentration for humic and fulvic acids) and at a
mid-low range of what would be expected (50 mg/L total concentration for Ca and Mg, 1 mg/L
total concentration for humic and fulvic acids). These spiked interferent levels were confirmed
through analysis of aliquots by ATEL. Also, each contaminant was added to these samples,
along with the potential interferent, at a concentration consistent with a lOx dilution of the lethal
dose. The resulting samples were analyzed in triplicate. Table 3-2 lists the PT samples analyzed
in this verification test for each contaminant.
Table 3-1. Lethal Dose of Target Contaminants
Contaminant
(common name)
VX
GB (sarin)
GD (soman)
aldicarb
dicrotophos
Oral Lethal Dose
Concentration
2.1 milligrams/liter (mg/L)
20 mg/L
1.4 mg/L
260 mg/L
1400 mg/L
Contaminant Class
Chemical agent
Chemical agent
Chemical agent
Carbamate pesticide
Organophosphate pesticide
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Table 3-2. Performance Test Samples
Type of PT
Sample
Sample Characteristics
Concentrations
Contaminant-
only
Contaminants in DI Water
VX: 2.1 to 0.00021 mg/L
GB:20to0.002mg/L
GD: 1.4 to 0.00014 mg/L
aldicarb: 260 to 0.026 mg/L
dicrotophos: 1400 to 0.14 mg/L
Contaminants in 1 mg/L humic
and fulvic acids
Interferent
Contaminants in 5 mg/L humic
and fulvic acids
Contaminants in 50 mg/L Ca
and Mg
Contaminants in 250 mg/L Ca
and Mg
VX: 0.21 mg/L
GB:2mg/L
GD: 0.14 mg/L
aldicarb: 26 mg/L
dicrotophos: 140 mg/L
3.2.2 DWSamples
Table 3-3 lists the DW samples analyzed for each contaminant in this test. DW samples were
collected from four geographically distributed municipal sources (Ohio, New York, California,
and Florida) to evaluate the performance of the OP/C Screen Kit with various DW matrices.
These samples varied in their source, treatment, and disinfection process. All samples had
undergone either chlorination or chloramination disinfection prior to receipt. Samples were
collected from water utility systems with the following treatment and source characteristics:
• Chlorinated filtered surface water source
• Chlorinated unfiltered surface water source
• Chlorinated filtered groundwater source
• Chloraminated filtered surface water source
Approximately 175 liters (L) of each of the DW samples were collected in pre-cleaned,
translucent, low-density polyethylene containers. After sample collection, an aliquot of each
DW sample was sent to ATEL to determine the following water quality parameters:
concentration of trihalomethanes, haloacetic acids, total organic halides, Ca and Mg, pH,
conductivity, alkalinity, turbidity, organic carbon, and hardness. All DW samples were
dechlorinated prior to their use with sodium thiosulfate pentahydrate to prevent the degradation
of the target contaminants by chlorine. The dechlorination of the DW was qualitatively
confirmed by adding a diethyl-p-phenylene diamine (DPD) tablet to an aliquot of DW. If the
water did not turn pink, the dechlorination process was successful. If the water did turn pink,
additional dechlorinating reagent was added and the dechlorination confirmation procedure
repeated. Each DW sample was analyzed before addition of contaminant, as well as after
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fortification with each individual contaminant at a single concentration level (lOx dilution of the
lethal dose). Aliquots of each contaminant stock solution were diluted with DW samples to the
appropriate concentration. Each sample was tested in triplicate.
Table 3-3. Drinking Water Samples
Drinking Water Sample Description
Water
Utility
Columbus, Ohio
(OH DW)
New York City, New
York (NY DW)
Orlando, Florida
(FL DW)
Metropolitan Water
District of Southern
California (CA DW)
Water
Treatment
chlorinated
filtered
chlorinated
unfiltered
chlorinated
filtered
chloraminated
filtered
Source
Type
surface
surface
ground
surface
Contaminant Concentrations
VX: 0.21 mg/L
GB: 2.0 mg/L
GD: 0.14 mg/L
aldicarb: 26 mg/L
dicrotophos: 140 mg/L
3.2.3 QCSamples
QC samples included method blank (MB) samples consisting of ASTM Type IIDI water and
positive and negative control samples, as provided with each OP/C Screen Kit. Positive and
negative control samples were prepared and used according to the protocol provided by the
vendor. One set each of duplicate positive and negative control samples were tested with each
kit. All MB QC samples were exposed to sample preparation and analysis procedures identical
to the test samples. The MB samples were used to ensure that no sources of contamination were
introduced in the sample handling and analysis procedures. At least 10% of the test samples
(seven samples for each contaminant) were MB samples. For samples involving GD, only five
MB samples were run. The test samples and MB samples were analyzed blindly by the operator
in that the samples used for analysis were prepared by someone other than the operator and were
marked with non-identifying numbers.
3.2.4 Operational Factors
3.2.4.1 Technical Operator
All of the test samples were analyzed by a technical operator who was trained by the vendor.
Operational factors such as ease of use and sample throughput were evaluated based on
observations recorded by the technical operator and the Verification Test Coordinator.
Operational factors were noted during the laboratory portions of the verification test. These
observations are summarized to describe the operational performance of the OP/C Screen Kit in
this verification.
3.2.4.2 Non-Technical Operator
A subset of the samples was also tested by a non-technical operator using the OP/C Screen Kit.
The non-technical operator was someone with little to no laboratory experience who would be
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representative of a first responder. For this test, the non-technical operator was a State of Ohio
certified firefighter with Hazardous Waste Operations and Emergency Response (HAZWOPER)
training. The non-technical operator was trained in the use of the OP/C Screen Kit by another
Battelle staff person who was trained by the vendor. Because many of the contaminants being
tested are highly toxic and unsafe to be handled outside of a special facility, MB samples and
non-toxic positive and negative control samples were analyzed as part of the operational factors
assessment. The positive and negative control samples were provided by the vendor and prepared
and used according to the vendor's protocol as described in the previous section. Because no
samples spiked with the contaminants of interest were used, only the operational aspects of the
OP/C Screen Kit were evaluated with the non-technical operator. As the OP/C Screen Kit may be
used by first-responders, its performance was evaluated under simulated first-response
conditions by having the operator dressed in a Level B protective suit, neoprene latex gloves,
boots, and a self-contained breathing apparatus (SCBA). The operator had prior experience
working in personal protective equipment (PPE). One set of MB samples was also tested without
the use of PPE. Ease of use from the perspective of the operator was documented both with and
without the PPE.
3.3 Verification Schedule
The verification test of the OP/C Screen Kit took place from November 2005 through February
2006 at Battelle facilities in Columbus and West Jefferson, Ohio.
3.4 Test Procedure
3.4.1 Test Sample Preparation and Storage
All testing for this verification test was conducted within Battelle laboratories. Aldicarb and
dicrotophos samples were tested at Battelle's Columbus laboratories, while VX, GB, and GD
samples were tested at Battelle's Hazardous Materials Research Center (HMRC) facility in West
Jefferson, OH. Appropriate safety guidelines associated with each laboratory were followed
throughout the verification test. Samples were prepared fresh each day from stock solutions in
either DI water, an interferent matrix, or a DW matrix. Sample solutions were prepared to the
specified concentration based on the concentration of the stock solution, which was confirmed
through reference analysis. Test solutions were prepared in 1L quantities such that appropriate
aliquots (100 |j,L) of the sample preparation could be used for each test sample. Triplicate
samples of 100 |jL each were taken from the same sample preparation. Each sample was placed
in its own container and labeled only with a sample identification number that was also recorded
in a laboratory record book (LRB) along with details of the sample preparation.
3.4.2 Test Sample Analysis Procedure
Before testing with the OP/C Screen Kit could begin, three reagents that were included in the kit
had to be prepared: ACh-E, the oxidizer, and the substrate (ATC). Using a 3mL transfer pipette,
2 mL of the Ach-E diluent was transferred from the test tube to the ACh-E dropper bottle, which
contained freeze-dried ACh-E. The bottle was then mixed by shaking it moderately. The ACh-E
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solution was allowed to sit for at least 15 minutes to allow the ACh-E to go into solution. To
prepare the oxidizer, 200 |jL of the oxidizer was added to the appropriate dropper bottle and
mixed. To prepare the substrate, 2 mL of substrate diluent were added to the appropriate dropper
bottle and mixed.
The test tubes supplied with the OP/C Screen Kit were labeled. Then 100 |jL of the control
solution or the test sample was added to the appropriate test tubes. Two drops of the oxidizer
were then added to each test tube and the tubes were shaken. The tubes were then allowed to
incubate at room temperature for five minutes. Two drops of neutralizer were then added to each
test tube and the tubes were shaken. Next, two drops of the ACh-E solutions were added to each
test tube, the tubes were shaken, and the tubes were then allowed to incubate at room
temperature for 30 minutes. After 30 minutes, two drops of the ATC substrate solution were
added to each test tube and the tubes were shaken. Then, two drops of chromogen were added to
each test tube, the tubes were shaken and then allowed to incubate for 30 minutes. Finally, two
drops of the stopping solution were added to each tube to stop the reaction. Each tube was then
placed in the colorimeter (Hach Company) provided by the vendor and the reading was recorded.
The color of the sample was also recorded on the data sheet.
To determine if the sample was positive or negative, a percent inhibition had to be calculated for
each sample (see Chapter 6). A sample was considered positive if it had reduced color
development when compared to the negative control. Specifically, 20% or more inhibition of the
color, obtained through the inhibition calculations, indicated a positive sample. Less than 20%
inhibition indicated a negative or non-contaminated sample.
Per the kit instructions, duplicate samples were run for each test sample. Positive and negative
controls were also run with each batch of samples. A batch consisted of up to 8 samples. Each
of the dropper bottles used in the test was color-coded to coincide with the instructions. Actual
solution names are presented here instead of the colors used in the kit instructions.
3.4.3 Drinking Water Characterization
An aliquot of each DW sample, collected as described in Section 3.2.2, was sent to ATEL to
determine the following water quality parameters: turbidity; concentration of dissolved and total
organic carbon; conductivity; alkalinity; pH; concentration of Ca and Mg; hardness; and
concentration of total organic halides, trihalomethanes, and haloacetic acids. Table 3-4 lists the
characterization data from the four water sample types used in this verification test. Water
samples were collected and water quality parameters were measured by ATEL in June 2005,
while verification testing was tested with the DW between November 2005 and February 2006.
The time delay between collection and testing was due to the fact that the water samples were
collected for use during a separate ETV test conducted prior to this one. Because of this, an
aliquot of each DW was tested by ATEL again in January 2006 to verify some of the parameters
with the most potential to change over time. Note that dissolved organic carbon was not retested
as this result was verified by the total organic carbon results, additionally the total organic
halides and calcium and magnesium were not verified as there was no reason to expect a change
in these parameters. The concentrations of most water quality parameters were similar; however,
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there was a decrease in levels of volatile compounds such as trihalomethanes and haloacetic
acids over this time-period.
Table 3-4. ATEL Water Quality Characterization of Drinking Water Samples
Parameter
Turbidity
Dissolved
Organic Carbon
Total Organic
Carbon
Specific
Conductivity
Alkalinity
pH
Calcium
Magnesium
Hardness
Total Organic
Halides
Trihalomethanes
Haloacetic Acids
Unit
NTU(a)
mg/L
mg/L
uMHO(c)
mg/L
mg/L
mg/L
mg/L
ug/L
ug/L/
analyte
ug/L/
analyte
Method
EPA180.1(4)
SM5310(5)
SM5310(5)
SM2510(5)
SM 2320(5)
EPA 150.1(6)
EPA200.8(7)
EPA200.8(7)
EPA 130.2(8)
SM 5320(5)
EPA 524.2(9)
EPA 552.2(10)
Columbus,
OH
(OH DW)
2005
0.1
2.1
2.1
572
40
7.6
33
7.7
118
220
74.9
32.8
2006
0.6
NA
2.3
602
44
7.4
NA
NA
107
NA
16.6
<6.0
New York
City, NY
(NY DW)
2005
1.1
1.1
1.6
84
14
6.9
5.6
1.3
20
82
39.0
39.0
2006
1.3
NA
4.1
78
12
6.8
NA
NA
26
NA
23.1
<6.0
Orlando, FL
(FL DW)
2005
0.5
1.6
1.7
322
142
8.5
8.8
43
143
300
56.4
34.6
2006
0.1
NA
2.1
325
125
7.6
NA
NA
130
NA
41.8
<6.0
MWD (b), CA
(CA DW)
2005
0.1
2.9
2.5
807
71
8.0
45
20
192
170
39.2
17.4
2006
0.2
NA
2.7
812
97
7.9
NA
NA
182
NA
24.1
<6.0
(a) NTU = Nephelometric turbidity unit.
(b) MWD = Metropolitan Water District of Southern California
(iMHO = micromho
10
-------
Chapter 4
Quality Assurance/Quality Control
QA/QC procedures were performed in accordance with the quality management plan (QMP) for
the AMS Center(11) and the test/QA plan(12) for this verification test.
QC procedures as noted in the reference methods or laboratory's operating procedures were
followed in confirming analyses of stock or reference solutions of contaminants and interfering
compounds and in characterizing the DW. The reference methods for this verification test are
listed in Table 4-1. A summary of the QC samples and acceptance criteria associated with each
method is presented in Table 7 in the test/QA plan.(12)
4.1 Sample Chain-of Custody Procedures
Sample custody was documented throughout collection, shipping, and analysis of the samples.
Sample chain-of-custody procedures were in accordance with ASAT.I-009-DRAFT, Standard
Operating Procedure for Sample Chain of Custody. The chain-of-custody forms summarized the
samples collected and analyses requested and were signed by the person relinquishing samples
once that person had verified that the custody forms were accurate. The original sample custody
forms accompanied the samples; the shipper kept a copy. Upon receipt at the sample destination,
sample custody forms were signed by the person receiving the samples once that person had
verified that all samples identified on the custody forms were present in the shipping container.
4.2 QC Samples
The QC measures for the reference methods included the analysis of a MB sample with the
analyses of the reference or stock solution. MB samples were analyzed to ensure that no sources
of contamination were present. If the analysis of an MB sample indicated a concentration above
the minimum detection limit for the confirmatory instrument, contamination was suspected. Any
contamination source(s) were corrected, and proper blank readings were achieved, before
proceeding with the analyses. In general, a matrix spike or laboratory fortified spike sample was
also analyzed. Average acceptable recoveries for these samples were between 70 and 150%.
Samples outside of the acceptable range were generally flagged and rerun once the QC
acceptance criteria had been met. QC samples were run with every batch of 1 to 20 samples.
Specific QC samples and acceptance criteria associated with each method can be found in the
appropriate reference (Table 4-1).
11
-------
Table 4-1. Reference Methods for Target Contaminants and Interferents
Target
Analyte/Interferent
VX
GB (sarin)
GD (soman)
aldicarb
dicrotophos
calcium (Ca)
magnesium (Mg)
Humic and fulvic
acids
Reference Method
(Instrumentation)
Battelle Internally
Developed Method (LC-MS)
HMRC-IV-1 18-05 (13)
(GC-MS)
HMRC-IV-1 18-05 (13)
(GC-MS)
SOP for Analysis of Water
Sample Extracts for Type 1
Analytes by Liquid
Chromatography/Mass
Spectrometry (14) (LC-MS)
SOP for Extracting and
Preparing Water Samples for
Analysis of Dicrotophos,
Mevinphos, and
Dichlorovos (15) (GC-MS)
EPA 200.8 (7)(ICP-MS)
EPA 200.8 (7)(ICP-MS)
Standard Method 53 10 (5)
Combustion Infrared NDR
Number of
Observations
10
4
4
2
2
4
1
1
1
1
Expected
Concentrations
(mg/L)
2.1
20.0
1.4
26.0
260
140
1400
125
125
1.0
Average
Measured
Concentration
(mg/L) ± SD
2.1±0.1
17.0 ±1.4
1.7 ±0.05
34
303
157 ± 24
1326
140
130
0.9
Recovery
(%R) ± SD
101 ±5
85 ±7
121 ±4
123 ±7 (a)
108 ± 17 (a)
112
104
90
a> Average of two concentration levels.
QC samples as provided with the OP/C Screen Kit were also run per the vendor's instructions,
and MB samples were run as part of the verification test (Section 3.2.3). At least seven MB
samples were run with each set of chemical agent and pesticide samples except for GD, for
which only five MB samples were run. For the pesticides, 17 MB samples were tested with
aldicarb samples while 16 MB samples were tested with dicrotophos samples. Seven out of
17 and one out of 16 MB samples were positive for aldicarb and dicrotophos, respectively.
There was no indication of contamination despite positive MB results on days when those
samples were run. Eight MB samples were run with the GB sample set. All but one MB
12
-------
returned a negative result. The positive GB MB sample had only a 23% inhibition and a pale
yellow color. Only five MB samples were run for GD, and three out of five were positive. In
one case, the pair of duplicates had significantly different colorimeter readings such that one of
the duplicates was negative and one was positive. The average was negative. This discrepancy
is believed to be related to issues regarding the colorimeter's reproducibility (see Chapter 6).
Other samples tested in the same sample set as this MB produced no unexpected results, though
the colorimeter readings for all but on set of duplicate samples in this sample set were
significantly different from each other. Three of the seven MB samples tested with the VX
sample set were positive. One sample was run in the same batch as two unspiked interferent PT
sample replicates with positive results. However, other samples in that batch did not show signs
of contamination. There were also no indications of contamination in sample batches where
other positive MB samples were found for the chemical agent samples, despite the positive MB
results.
4.3 Equipment/Calibration
The instruments used for the reference analyses were calibrated per the standard reference
methods being used to make each measurement or the standard operating procedures (SOPs) of
the analysis laboratory. Instruments used in the reference analyses for this test included gas
chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-
MS), pH electrodes, inductively coupled plasma-mass spectrometry (ICP-MS), and gas
chromatography with electron capture detector (GC-ECD). All calibrations were documented by
Battelle in the project laboratory record book (LRB). Calibration of mass spectrometers involved
a 4- to 8-point calibration curve covering the range of concentrations of the reference solutions to
be analyzed. Calibration of each reference instrument was performed as frequently as required by
the reference method guidelines.
The vendor provided the Battelle technical operator with instructions on how to properly
maintain components of the OP/C Screen Kit requiring calibration, namely the colorimeter. The
colorimeter was calibrated at the beginning of each day of testing.
Pipettes used during solution preparation were maintained and calibrated as required by Battelle
SOPs (i.e., minimum of every 6 months). Pipettes were checked and either recalibrated or
replaced if they were dropped over the course of testing. Pipettes supplied as part of the OP/C
Screen Kit were used according to the vendor's instructions and could not be calibrated.
4.4 Characterization of Stock Solutions
During testing, aliquots of the stock solutions used for sample preparation were submitted for
concentration confirmation via the respective methods. The results, along with the reference
methods, are listed in Table 4-1. Averages and associated standard deviations are given in cases
where more than two samples were tested. Recovery (%R) is calculated by the following
equation:
S~1
— xWO 0)
A
13
-------
where C is the measured concentration (or average measured concentration if more than one
sample was tested) and^4 is the expected concentration of the contaminant or interferent in
solution. For aldicarb and dicrotophos, aliquots at two different concentration levels were
confirmed through reference analysis. The %R, listed in Table 4-1, represents the average of the
%R across both concentration levels for those compounds. Table 4-1 shows that %R values
ranged from 85% to 123% across all analytes and interferents.
Contaminant stock solutions were prepared and tested individually. Interferent stock solutions
contained multiple analytes in the same solution (e.g., calcium and magnesium or humic and
fulvic acids together). Up to four aliquots of each stock solution were analyzed over the course
of the verification test. In the case of VX, extra aliquots were analyzed and all were reported in
Table 4-1. Aliquots were preserved or extracted on the day of preparation and stored as
prescribed by the standard method.
4.5 Audits
4.5.1 Performance Evaluation Audit
The concentration of the standards used to prepare the samples fortified with contaminants and
potential interfering compounds was confirmed by analyzing standards prepared in ASTM Type
IIDI water from two separate commercial vendors using the reference methods noted in
Table 4-1. The standards from one vendor were used during the verification test, while the
standards from the second vendor were used exclusively to confirm the accuracy of the standards
from the first vendor.
Given the security requirements and lack of alternate sources for the chemical agents (VX, GB,
and GD) used in this verification test, PE audits were not performed for these contaminants. PE
audits were done for all remaining compounds when more than one source of the contaminant or
potential interfering compounds was available. PE audits were performed only on compounds
used to prepare test samples and not on any solutions supplied as part of the OP/C Screen Kit.
Agreement of the standards within 25% (percent difference) was required for the measurements
to be considered acceptable. The percent difference (%D) between the measured concentration of
the PE sample and the nominal concentration of that sample was calculated using the following
equation:
M
%D = —xlOO (2)
f\_
where Mis the absolute value of the difference between the measured and the expected
concentration, and^4 is the expected concentration. The results of the PE samples are given in
Table 4-2. All %D values calculated were within the 25% acceptable tolerance.
14
-------
Table 4-2. Performance Evaluation Samples and Percent Difference
Contaminant
aldicarb
dicrotophos
Ca
Mg
Expected
Concentration
(ng/mL)
50
1000
1000
1000
Measured
Concentration
(ng/mL)
57
1103
890
990
Percent
Difference
(%)
14
10
11
1
4.5.2 Technical Systems A udit
The Battelle Quality Manager conducted technical systems audits (TSAs) in November 2005
(11/01, 11/11, 11/16, 11/18), December 2005 (12/01, 12/29), and January 2006 (01/30) to ensure
that the verification test was performed in accordance with the AMS Center QMP,(11) the test/QA
plan,(12) published reference methods, and any SOPs used by Battelle. As part of the audit, the
Battelle Quality Manager reviewed the reference methods, compared actual test procedures to
those specified or referenced in the test/QA plan, and reviewed data acquisition and handling
procedures. The Battelle Quality Manager also observed testing in progress and the reference
method sample preparation and analysis, inspected documentation, and reviewed the LRBs used
to record testing results. The Battelle Quality Manager also checked calibration certifications and
conferred with Battelle staff. Observations and findings from this audit were documented and
submitted to the Battelle Verification Test Coordinator for response. No major findings were
reported from the audits. The records concerning the TSA are permanently stored with the
Battelle Quality Manager.
4.5.3 Audit of Data Quality
At least 10% of the data acquired during the verification test was audited. The Battelle Quality
Manager traced the data from initial acquisition, through reduction and statistical comparisons, to
final reporting. All calculations performed on the data undergoing the audit were checked.
4.6 QA/QC Reporting
Each assessment and audit was documented in accordance with Section 3.3.4 of the AMS Center
QMP.(11) Once the assessment report was prepared, the Battelle Verification Test Coordinator
responded to each potential problem and implemented any necessary follow-up corrective action.
The Battelle Quality Manager ensured that follow-up corrective action was taken. The results of
the TSA were sent to the EPA.
4.7 Data Review
Records generated in the verification test were reviewed before they were used to calculate,
evaluate, or report verification results. Table 4-3 summarizes the types of data recorded. The
review was performed by a technical staff member involved in the verification test but not the
15
-------
staff member who originally generated the record. The person performing the review added
his/her initials and the date to a hard copy of the record being reviewed.
Table 4-3. Summary of Data Recording Process
Data to Be Recorded
Dates, times, and
details of test events
Sample preparation
(dates, concentrations,
etc.)
Enzymatic test kit
procedures and sample
results
Reference method
sample preparation
Reference method
procedures,
calibrations, QA, etc.
Reference method
analysis results
Responsible
Party
Battelle
Battelle
Battelle
Battelle
Battelle or
subcontract
laboratory
Battelle or
subcontract
laboratory
Where
Recorded
ETV laboratory
record book or
data recording
forms
ETV laboratory
record books
ETV data sheets
and laboratory
record book
ETV laboratory
record book
Laboratory
record book or
data recording
forms
Electronically
from reference
analytical method
How Often
Recorded
Start/end of test
procedure, and at
each change of a
test parameter
When each
solution was
prepared
Throughout test
duration
Throughout
sample
preparation
Throughout
sampling and
analysis
processes
Every sample
analysis
Disposition
of Data
Used to organize and
check test results and
manually incorporated
into data spreadsheets
as necessary
Used to confirm the
concentration and
integrity of the
samples analyzed
Manually incorporated
into data spreadsheets
for statistical analysis
and comparisons
Used to demonstrate
validity of samples
submitted for
reference
measurements
Retained as
documentation of
reference method
performance
Converted to
spreadsheets for
calculations
16
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Chapter 5
Statistical Methods and Reported Parameters
The OP/C Screen Kit was evaluated for qualitative results (i.e., positive/negative responses to
samples). All data analyses were based on these qualitative results. QC and MB samples were
not included in any of the analyses.
5.1 Accuracy
Accuracy was assessed by evaluating how often the OP/C Screen Kit result was positive in the
presence of a concentration above the limit of detection (LOD). Contaminant-only PT samples
were used for this analysis. An overall percent agreement was determined by dividing the
number of positive responses by the overall number of analyses of contaminant-only PT samples
greater than the OP/C Screen Kit's LOD (see Equation 3). If the LOD was not known or
available, then all analyzed contaminant-only PT samples greater than the concentration level
where consistent negative results were obtained were used.
Accuracy (% Agreement) = # of positive contaminant only PT samples x 100 (3)
total # of contaminant only PT samples
5.2 False Positive/False Negative Rates
A false positive response was defined as a response indicating the presence of a contaminant
when the PT interferent or DW sample was not spiked with contaminant. A false positive rate
was reported as the number of false positive results out of the total number of unspiked samples
(Equation 4).
A false negative response was defined as a response indicating the absence of a contaminant
when the sample was spiked with a contaminant at a concentration greater than the OP/C Screen
Kit's LOD as defined above. Spiked PT (contaminant and interferent) samples and spiked DW
samples were included in the analysis. Contaminant-only PT samples above the OP/C Screen
Kit's LOD or the level at which consistent negative responses are obtained (when the LOD was
not known) were included in the analysis. A false negative rate was evaluated as the number of
false negative results out of the total number of spiked samples for a particular contaminant
(Equation 5).
False Positive Rate = # of positive results (4)
total # of unspiked samples
17
-------
False Negative Rate = # of negative results (5)
total # of spiked samples
5.3 Precision
Precision measures the repeatability and reproducibility of the OP/C Screen Kit's responses. The
precision of three replicates of each sample set was assessed. Responses were considered
inconsistent if one or more of the three replicates differed from the response of the other samples
in the replicate set. The precision for the OP/C Screen Kit was assessed by calculating the overall
number of consistent responses for all the sample sets. The results are reported as the percentage
of consistent responses out of all replicate sets (Equation 6).
Precision (% Consistent results) = # of consistent responses of replicate sets x 100 (6)
total # of replicate sets
5.4 Potential Matrix and Interferent Effects
The potential effect of the DW matrix on the OP/C Screen Kit's performance was evaluated
qualitatively by comparing the results for the spiked and unspiked DW samples to those for the
PT samples spiked with the contaminant at 10 times less than the lethal dose. Similarly, the
potential effect of interferent PT samples was evaluated. The results indicating the correct or
incorrect reporting of the presence of a contaminant were evaluated. The findings are reported
and discussed in Section 6.4.
5.5 Operational Factors
Operational aspects of the OP/C Screen Kit's performance such as ease of use and sample
throughput were evaluated through observations made during testing. Also addressed are the
qualitative observations of the verification staff pertaining to the performance of the OP/C
Screen Kit from both the technical and non-technical operators' perspective.
18
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Chapter 6
Test Results
The OP/C Screen Kit is a qualitative, colorimetric detection technology. The test tubes in which
the test is performed produce a color ranging from yellow (negative control) to clear (positive
control). The absorbance of the sample was read on a 450 nm colorimeter. To determine
whether or not a sample is positive, the absorbance of the sample was compared to that of the
negative control by calculating the percent inhibition. Because duplicate samples were tested for
each test and negative control sample, the average absorbance of the duplicates must first be
calculated before the percent inhibition can be determined. Percent inhibition was then
calculated using the following equation:
%inhibition =
1 sample
. control
xlOO (7)
where Lsampie is the average absorbance of the duplicate test sample and Lcontroi is the average
absorbance of the duplicate negative control samples. A sample was considered positive if it had
reduced color development when compared to the negative control. Specifically, 20% or more
inhibition of the color, obtained through the inhibition calculation, indicated a positive sample.
Less than 20% inhibition indicated a negative or non-contaminated sample. Based on these
inhibition parameters, a qualitative (positive or negative) result was recorded for each sample.
All of the test results presented in this chapter were calculated using the qualitative responses
determined for the OP/C Screen Kit.
After the completion of testing, the vendor discovered reproducibility issues with the Hach
colorimeter that was used during testing. Reproducibility is important for this test, particularly
for the negative control samples, which are used as a baseline in determining percent inhibition.
To denote the colorimeter problem, a relative percent difference (RPD) was calculated for each
pair of duplicate negative control samples. RPD was calculated using the following equation:
2x\NC,-NC2
RPD(%)= ' ' 2
xlOO (8)
where NCi and NC2 are the duplicate negative control samples. Based on the vendor's direction,
any pair of negative control samples with a RPD of >20% were flagged. The vendor indicated
that an RPD of >20% would lead to retesting for that set of samples associated with the negative
19
-------
controls. Because testing was already completed when the colorimeter problem was discovered,
suspect data were only flagged in this report. All data were used in calculating the results
presented in this chapter. Results obtained from a set of samples where the RPD was >20% are
marked accordingly in the tables 6-2a through 6-2e.
6.1 Accuracy
The accuracy results for the OP/C Screen Kit using the contaminant-only PT samples are
discussed in this section. Table 6-1 presents the accuracy results for aldicarb, dicrotophos, VX,
GB, and GD. The results for the lethal dose concentration of each contaminant are included in
the table. Results are presented for all tested concentration levels; but, by definition, only those
results above the kit's LOD are included in the calculation. The LOD for aldicarb is 0.010 mg/L.
The LOD for dicrotophos is 0.004 mg/L. Both of these LODs are below the lowest
concentration level tested for this test. Thus, all of the pesticide contaminant-only PT samples
were included in the accuracy calculations for these compounds. LODs were not available for
VX, GB, or GD. For these contaminants, only samples above the level where consistent
negative responses were obtained were used in the accuracy calculations for that contaminant.
For VX, consistent negative responses were found at a l,000x dilution of the lethal dose, or
0.0021 mg/L. Consistent negative responses were not found for GB, so all contaminant-only PT
samples were included in the accuracy calculations. For GD, consistent negative responses were
found at the lowest tested concentration level (0.00014 mg/L); thus, those PT samples were not
used in any accuracy calculations.
All concentration levels of VX and GD samples tested above the level of consistent negative
responses for each contaminant generated 3 out of 3 positive responses, resulting in 100%
accuracy for each chemical agent. All concentration levels analyzed for GB generated positive
responses for all replicates, resulting in 100% accuracy. Results for contaminant-only PT
samples containing aldicarb and dicrotophos were all positive across all concentration levels
tested resulting in 100% accuracy for both pesticides.
6.2 False Positive/False Negative Rates
Contaminant-only PT samples, interferent PT samples, and DW samples were evaluated to
determine false positive and false negative results for the OP/C Screen Kit. A false positive
response was defined as a positive result when the contaminant was not spiked into the sample.
A false negative response was defined as a negative result when the sample was spiked with a
contaminant at a concentration greater than the level where consistent negative responses were
obtained (see Section 6.1). Tables 6-2a through 6-2e present the false positive and false negative
responses for VX, GB, GD, aldicarb, and dicrotophos, respectively. The number of positive
samples out of the total replicates analyzed is presented in each table. Also presented in each
table are the RPD values for the negative controls associated with that particular set of replicates.
Only RPDs >20% are presented in the table as a means of flagging suspect data (see Chapter 6
introduction). These data were still used in the false positive/negative calculations for the table.
20
-------
Table 6-1. Contaminant-Only PT Sample Results
„ , , Concentration
Contaminant , _ ,
(mg/L)
2.1 (a)
0.21
VX 0.021
0.0021
0.00021
20(a)
2.0
GB 0.20
0.020
0.0020
14(a)
0.14
GD 0.014
0.0014
0.00014
260 (a)
26
Aldicarb 2.6
0.26
0.026
1400(a)
140
Dicrotophos 14
1.4
0.14
Positive Results
Out of
Total Replicates
3/3
3/3
3/3
0/3 (b)
0/3 (b)
3/3
3/3
3/3
3/3
3/3
3/3
3/3
3/3
3/3
0/3 (b)
3/3
3/3
3/3
3/3
3/3
3/3
3/3
3/3
3/3
3/3
Overall
Accuracy
100% (9/9)
100% (15/15)
100% (12/12)
100% (15/15)
100% (15/15)
(a) Lethal dose.
(b) Not used in accuracy calculations because samples are at or below LOD or level or consistent negative responses.
21
-------
Table 6-2a. VX False Positive/Negative Results
Sample Type
Contaminant-
only PT samples
Interferent PT
samples (d)
DW samples (d)
Matrix
DI water
DI water
DI water
1 mg/L humic and
fulvic acids
1 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
50 mg/L Ca and Mg
50 mg/L Ca and Mg
250 mg/L Ca and
Mg
250 mg/L Ca and
Mg
OHDW
OHDW
CADW
CADW
FLOW
FLOW
NYDW
NYDW
Concentration
(mg/L)
2.1(c)
0.21
0.021
Blank
0.21
Blank
0.21
Blank
0.21
Blank
0.21
Blank
0.21
Blank
0.21
Blank
0.21
Blank
0.21
False Positive Rate
False Negative Rate
Positive Results
Out of
Total Replicates (a)
3/3
3/3
3/3
2/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
1/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
3/24
0/33
RPD of Negative
Controls Associated
with Sample ^
37%
23%
37%
69%
28%
30%
69%
88%
37%
88%
(a) Boxed results indicate false positive responses.
(b) RPD provided only when >20%, indicating suspect data, according to vendor, because of colorimeter lack of
reproducibility.
(c) Lethal dose.
(d) Only one set of unspiked DW and PT interferent samples were run for VX, GB, and GD.
22
-------
Table 6-2b. GB False Positive/Negative Results
Sample Type Matrix
DI water
DI water
Contaminant-
only PT DI water
samples DI water
DI water
1 mg/L humic and
fulvic acids
1 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
5 mg/L humic and
Interferent PT fulvic acids
samples (d) 50 mg/L Ca and
Mg
50 mg/L Ca and
Mg
250 mg/L Ca and
Mg
250 mg/L Ca and
Mg
OHDW
OHDW
CADW
CA DW
DW
samples(d) FL DW
FLOW
NYDW
NYDW
False Positive Rate
False Negative Rate
(a) Boxed results indicate false positive
Concentration
\m& )
20(c)
2.0
0.20
0.020
0.0020
Blank
2.0
Blank
2.0
Blank
2.0
Blank
2.0
Blank
2.0
Blank
2.0
Blank
2.0
Blank
2.0
responses.
Positive Results
Out of
Total Replicates (a)
3/3
3/3
3/3
3/3
3/3
2/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
1/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
3/24
0/39
(b) RPD provided only when >20%, indicating suspect data, according to vendor, because
reproducibility.
(c) Lethal dose.
(d) Only one set of unspiked DW and PT interferent samples
RPD of Negative
Controls Associated
with Sample ^
61%
30%
61%
69%
30%
88%
88%
of colorimeter lack of
were run for VX, GB, and GD.
23
-------
Table 6-2c. GD False Positive/Negative Results
Sample Type Matrix
DI water
Contaminant- DI water
only PT
, DI water
samples
DI water
1 mg/L humic and
fulvic acids
1 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
5 mg/L humic and
Interferent PT fulvic acids
samples (d) 50 mg/L Ca and
Mg
50 mg/L Ca and
Mg
250 mg/L Ca and
Mg
250 mg/L Ca and
Mg
OHDW
OHDW
CADW
CA DW
DW
samples(d) FL DW
FLOW
NYDW
NYDW
False Positive Rate
False Negative Rate
(a) Boxed results indicate false positive
Concentration
(m& )
L4oo
0.14
0.014
0.0014
Blank
0.14
Blank
0.14
Blank
0.14
Blank
0.14
Blank
0.14
Blank
0.14
Blank
0.14
Blank
0.14
responses.
Positive Results
Out of
Total Replicates (a)
3/3
3/3
3/3
3/3
2/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
1/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
3/24
0/36
(b) RPD provided only when >20%, indicating suspect data, according to vendor, because
reproducibility.
(c) Lethal dose.
(d) Only one set of unspiked DW and PT interferent samples
RPD of Negative
Controls Associated
with Sample ^
69%
43%
30%
46%
43%
88%
46%
88%
of colorimeter lack of
were run for VX, GB, and GD.
24
-------
Table 6-2d. Aldicarb False Positive/Negative Results
Sample Type
Contaminant-
only PT
samples
Interferent PT
samples
DW samples
Matrix
DI water
DI water
DI water
DI water
DI water
1 mg/L humic and
fulvic acids
1 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
50 mg/L Ca and
Mg
50 mg/L Ca and
Mg
250 mg/L Ca and
Mg
250 mg/L Ca and
Mg
OHDW
OHDW
CADW
CADW
FLOW
FLOW
NYDW
NYDW
False Positive Rate
False Negative Rate
Concentration
(mg/L)
260 (c)
26
2.6
0.26
0.026
Blank
26
Blank
26
Blank
26
Blank
26
Blank
26
Blank
26
Blank
26
Blank
26
Positive Results
Out of
Total Replicates (a)
3/3
3/3
3/3
3/3
3/3
1/3
3/3
2/3
3/3
0/3
3/3
1/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
4/24
0/39
RPD of Negative
Controls Associated
with Sample ^
131%
22%
22%
28%
131%
72%
28%
28%
72%
23%
79%
23%
79%
40%
40%
71%
40%
71%
71%
(a) Boxed results indicate false positive responses.
(b) RPD provided only when >20%, indicating suspect data, according to vendor, because of colorimeter lack of
reproducibility.
(c) Lethal dose.
25
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Table 6-2e. Dicrotophos False Positive/Negative Results
Sample Type
Contaminant-
only PT
samples
Interferent PT
samples
DW samples
Matrix
DI water
DI water
DI water
DI water
DI water
1 mg/L humic and
fulvic acids
1 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
5 mg/L humic and
fulvic acids
50 mg/L Ca and
Mg
50 mg/L Ca and
Mg
250 mg/L Ca and
Mg
250 mg/L Ca and
Mg
OHDW
OHDW
CADW
CADW
FLOW
FLOW
NYDW
NYDW
Concentration
(mg/L)
1400 (c)
140
14
1.4
0.14
Blank
140
Blank
140
Blank
140
Blank
140
Blank
140
Blank
140
Blank
140
Blank
140
False Positive Rate
False Negative Rate
Positive Results
Out of
Total Replicates (a)
3/3
3/3
3/3
3/3
3/3
0/3
2/3
0/3
0/3
1/3
2/3
3/3
3/3
0/3
3/3
0/3
3/3
0/3
3/3
1/3
3/3
5/24
5/39
RPD of Negative
Controls Associated
with Sample (b)
24%
24%
24%
44%
382%
79%
382%
161%
382%
(a) Boxed results indicate false positive responses; shaded results indicate false negative responses.
(b) RPD provided only when >20%, indicating suspect data, according to vendor, because of colorimeter lack of
reproducibility.
(c) Lethal dose.
26
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For VX, GB, and GD, only one set of unspiked DW and PT interferent samples were run for all
three chemical agents. Thus, the unspiked DW and PT-interferent sample results shown in
Tables 6-2a through 6-2c are the same and from only one set of triplicate samples. For aldicarb
and dicrotophos, sets of unspiked DW and PT interferent samples were run separately for each
pesticide.
No false negative results were found for any of the contaminants except for dicrotophos. For
dicrotophos, five false negatives were found, all of which were spiked interferent PT samples.
Four negative results were obtained across the spiked humic and fulvic acid samples: three for
5 mg/L humic and fulvic acids and one for 1 mg/L humic and fulvic acids. One other negative
result was obtained for spiked 50 mg/L Ca and Mg.
False positive results were found for each contaminant. For VX, GB, and GD, three false
positive results were found: two for unspiked 1 mg/L humic and fulvic acids and one for
unspiked OH DW. Four false positive results were found for aldicarb. All were in the
interferent PT sample results. Two positive responses were obtained from the unspiked 5 mg/L
humic and fulvic acid samples. One false positive was found in the 1 mg/L humic and fulvic
acid replicates, and the other false positive occurred in the unspiked 250 mg/L Ca and Mg
interferent PT samples.
Five false positive results were generated for dicrotophos samples. All three of the unspiked
250 mg/L Ca and Mg samples were positive. One replicate of the unspiked 50 mg/L Ca and Mg
samples was positive as was one unspiked NY DW sample.
The RPD values presented in the tables indicate the difference between the duplicate negative
controls for a particular set of samples. To determine if the colorimeter's lack of reproducibility
was affecting the results, the inhibition was calculated for each sample replicate using the
duplicate negative control samples individually. This exercise was only done to gather further
information on the effect of the colorimeter; these results were not used to calculate any of the
parameters defined in Chapter 5 or generate any of the results presented in Chapter 6. For the
most part, the difference between the duplicate negative control values did not affect the
outcome of a replicate. That is, when each negative control was used individually to calculate
the inhibition for each sample, the overall qualitative results (positive or negative) were the same
as when the average of the negative controls were used. However, there were a few instances
where this was not the case.
The individual negative controls run for the sample set containing the unspiked 1 mg/L humic
and fulvic acids for the chemical agents produced different results for those replicates if the
results were calculated based on each negative control individually. Calculations based on one
negative control sample would result in two positive and one negative response for the replicate
set, the same results that using the average negative control value produced. Calculations using
the other negative control produced the exact opposite results (two negative and one positive).
Similarly, the individual negative controls for unspiked 250 mg/L Ca and Mg interferent PT
replicates for all chemical agent samples produced one positive and one negative result for one
of the replicates.
27
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The only other instance where using individual negative controls, as opposed to the average,
would make a difference in the overall results was for dicrotophos samples where the RPD was
382%. As with the samples outlined above, inhibition calculations conducted with one negative
control produced results exactly opposite of those found using the other negative control for all
samples in that particular sample set. In this instance, one negative control had a positive
colorimeter reading, while one had a negative colorimeter reading. The average of the two
negative controls was negative, and led to the same qualitative results as using the individual
negative control value (the same results shown in table 6-2e). Using only the positive negative
control sample led to qualitative results opposite of those given in Table 6-2e. This would mean
0/3 positive results for unspiked 250 mg/L Ca and Mg samples, 3/3 positive results for spiked
5 mg/L humic and fulvic acids, 3/3 positive results for spiked 50 mg/L Ca and Mg samples (only
one replicate was run with the suspect negative controls), and 3/3 positive results for spiked
1 mg/L humic and fulvic acid samples (only one replicate was run with the suspect negative
controls). Despite these few cases, the average of the duplicate negative controls was used to
calculate the inhibition, as indicated by the kit's protocol provided by the vendor, and because
the colorimeter issue and the calculation/criteria for acceptable negative control results were not
provided until after testing was completed.
6.3 Precision
The performance of the OP/C Screen Kit in measuring VX, GB, and GD within sets of three
replicates was consistent in 19 out of 21 samples sets (for each compound), indicating that 90%
of the samples sets showed consistent results for these contaminants. Two sets of samples were
inconsistent, the unspiked 1 mg/L humic and fulvic acids and the unspiked OH DW replicates.
Sample sets were consistent 86% of the time for aldicarb samples, where 18 out of 21 sample
sets had consistent results. Unspiked 1 mg/L and 5 mg/L humic and fulvic acid samples showed
inconsistent results as did unspiked 250 mg/L Ca and Mg replicates.
Four sets of replicates of dicrotophos samples generated inconsistent results, generating a
precision of 81% (17 out of 21 sets of samples were consistent). Two sets of spiked and two sets
of unspiked sample responses were inconsistent. Both 1 mg/L humic and fulvic acids and
50 mg/L Ca and Mg spiked with dicrotophos at 140 mg/L produced results that were not
consistent within the sample set. Unspiked 50 mg/L Ca and Mg replicates were also inconsistent
in their responses, as were unspiked NY DW samples.
6.4 Potential Matrix and Interferent Effects
6.4.1 Interferent PT Samples
The OP/C Screen Kit was able to readily and consistently detect VX, GB, GD, aldicarb, and
dicrotophos at 10 times less than the lethal dose in DI water (see Tables 6-2a - e). Across all
three chemical agents and aldicarb, all interferent PT samples spiked with the contaminant at
10 times less than the lethal dose produced positive responses. One set of spiked interferent PT
samples for dicrotophos produced consistent positive responses with the OP/C Screen Kit. All
28
-------
other spiked interferent PT samples for dicrotophos had at least one negative response, indicating
possible inhibitory effects to the OP/C Screen Kit for the interferents used in this test.
For all contaminants except dicrotophos, unspiked 1 mg/L humic and fulvic acids replicates had
at least one false positive result, further supporting the sensitivity of the OP/C Screen Kit to this
interferent. For both aldicarb and dicrotophos samples, unspiked interferent PT samples were, in
general, troublesome in three of the four unspiked sample sets for aldicarb and two of the four
unspiked sets for dicrotophos, producing at least one positive result. These results indicate
potential interferent effects for these two pesticides.
6.4.2 DWSamples
For the chemical agent sample sets, unspiked OH DW produced one positive result. For
dicrotophos sample sets, one unspiked NY DW replicate was positive. All other DW sample
results for VX, GB, GD, aldicarb, and dicrotophos were as expected. The discrepancies with OH
and NY DW samples could indicate that there could be potential confounding compounds in
these DW samples that the OP/C Screen Kit is sensitive to.
6.5 Operational Factors
6.5.1 Technical Operator
The OP/C Screen Kit was operated by one Battelle technician throughout testing with the
pesticides and by a different Battelle technician throughout testing with chemical agents.
The technicians were trained by the vendor in the operation of the test kit. Training was
conducted at Battelle for one half day by the vendor. Both technicians had extensive laboratory
experience.
The instructions provided with the kit were color-coded to aid the operator and laid out the test in
a step-by-step manner. The colors on the dropper bottles helped to guide the operator through
the testing and made using multiple test solutions easier. The caps on the sample test tubes were
difficult to remove such that the technicians had to be cautious in their removal so as not to spill
any of the buffer contained in the tubes. It also seemed that the dropper bottles did not
consistently deliver the same size droplet. The instructions indicate that the samples should
incubate for 15 to 30 minutes at various points throughout testing. However, during the initial
training phase of the verification test, it was determined that the samples had to incubate for
30 minutes to achieve the correct results. Overall, the OP/C Screen Kit was straightforward and
easy to use.
The OP/C Screen Kit needs to be refrigerated until use, and then all of the reagents must come to
room temperature before they can be used. Multiple testing solutions are required for the assay.
All of the solutions are provided with the kit. Three of the reagents used in testing must be
prepared before they can be used. One reagent (ACh-E) requires at least five minutes incubation
before it can be used, though the vendor requested that Battelle allow 15 minutes.
29
-------
Up to eight sets of duplicate samples can be tested at the same time using one OP/C Screen Kit.
Overall, it took the technical operators an average of 94 minutes to test seven samples. The
operators were able to test between one and five OP/C Screen Kits a day with four to eight
samples per kit.
6.5.2 Non-Technical Operator
Unspiked DI water samples were tested on the OP/C Screen Kit by a non-technical operator both
in and not in PPE (see Section 3.2.4). The non-technical operator was trained in the use of the
kit by a technical operator who had been trained by the vendor. The SCBA apparatus, including
the mask, was worn throughout the entire testing procedure when PPE was to be worn.
However, the operator ran the air from the SCBA only part of the time during testing to conserve
the tank. Figure 6-1 shows the full PPE as worn for this verification test. Figure 6-2 shows the
testing of the OP/C Screen Kit with PPE. Because this portion of the test was designed to
evaluate the operational aspects of the OP/C Screen Kit, the handheld colorimeter used in other
portions of this verification test was not used by the non-technical operator. Only color
observations were recorded for each MB sample. With the PPE on, all MB samples were
yellow; without the PPE, all MB samples were also yellow, indicating that the samples tested
negative when the non-technical ran the MB samples both in and out of PPE. Removing the
dropper tips for the OP/C Screen Kit dropper bottles was difficult to do in PPE. Also, when
transferring drops to the tubes during testing, it was difficult to see the drops through the SCBA
mask. The 100 |j,L pipettes supplied with the OP/C Screen Kit were slightly difficult to handle
while wearing gloves as part of the PPE, but manageable. The vendor recommends the use of a
laboratory pipettor for use in the field.
Even without PPE, removal of the caps from some of the test tubes was quite difficult for the
non-technical operator as it was for the technical operator (see 6.5.1), causing the solutions
inside to nearly spill out. Using the provided work station box to hold the samples proved to be
somewhat problematic as it was difficult to know which sample tubes had already been worked
on and which had not since the sample solution is not visible when the test tube is in the box.
Testing three MB samples in PPE using the OP/C Screen Kit took 82 minutes. Six MB samples
were tested by the non-technical operator while not wearing PPE, which took 86 minutes.
The instructions for the OP/C Screen Kit indicate that the test should be performed within a
specific temperature range (70±20° F/ 21±7° C) to achieve accurate results. Presumably this
would be difficult for a first responder in the field to control and could cause significant
problems in the ability of the kit to perform correctly, assuming there is a strong temperature
dependency. Also, the 15-30 minute incubation times that must be performed at various points
in the test would make it difficult on the operator if they had to spend that time in PPE. For all
of these reasons, the OP/C Screen Kit was felt to be not very first-responder friendly for use in
the field wearing PPE.
30
-------
Figure 6-1. Side View of PPE Worn by
Non-Technical Operator
Figure 6-2. Testing of the OP/C
Screen Kit with the Non-
Technical Operator Wearing
PPE
-------
Chapter 7
Performance Summary
The OP/C Screen Kit results for this verification test for samples containing VX, GB, GD,
aldicarb, and dicrotophos are presented in Tables 7-1 through 7-5. The results for each
contaminant are presented in a separate table. Qualitative responses for each set of sample
replicates as well as accuracy, false negatives and positives, and precision are presented in each
table. A summary of the other performance factors associated with the OP/C Screen Kit is
presented at the end of this chapter. These performance factors apply across all contaminants.
32
-------
Table 7-1. VX Summary Table
Parameter
Qualitative
Results
Contaminant-
Only PT
Samples
Interferent PT
Samples
DW Samples
Accuracy
Matrix
DI Water
Humic and Fulvic
Acids
Ca and Mg
DW
VX
Concentration
2.1mg/L(a)
0.21 mg/L
0.021 mg/L
0.0021 mg/L
0.00021 mg/L
0.21 mg/L
0.21 mg/L
0.21 mg/L
Number
Detected/Number
of Samples
3/3
3/3
3/3
0/3 (b)
0/3 (b)
6/6
6/6
12/12
100% (9 out of 9) of the contaminant-only PT samples were
positive.
False Positives
Three false positive responses were obtained. Two positive
responses were found for unspiked 1 mg/L humic and fulvic
acids. One replicate for unspiked OH DW returned a positive
result.
False Negatives
Precision
No false negative results were obtained for spiked PT and DW
samples.
90% (19 out of 21) of the sample sets showed consistent
results among the individual replicates within that set.
(a) Lethal dose.
(b) Not used in accuracy calculations because samples are at or below level of consistent negative response.
33
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Table 7-2. GB Summary Table
Parameter
Qualitative
Results
Contaminant-
Only PT
Samples
Interferent PT
Samples
DW Samples
Accuracy
Matrix
DI Water
Humic and Fulvic
Acids
Ca and Mg
DW
GB
Concentration
20 mg/L (a)
2.0 mg/L
0.20 mg/L
0.020 mg/L
0.0020 mg/L
2.0 mg/L
2.0 mg/L
2.0 mg/L
Number
Detected/Number
of Samples
3/3
3/3
3/3
3/3
3/3
6/6
6/6
12/12
100% (15 out of 15) of the contaminant-only PT samples were
positive.
False Positives
Three false positive responses were obtained. Two positive
responses were found for unspiked 1 mg/L humic and fulvic
acids. One replicate for unspiked OH DW returned a positive
result.
False Negatives
Precision
No false negative results were obtained for spiked PT and DW
samples.
90% (19 out of 21) of the sample sets showed consistent results
among the individual replicates within that set.
Lethal dose.
34
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Table 7-3. GD Summary Table
Parameter
Qualitative
Results
Contaminant-
Only PT
Samples
Interferent PT
Samples
DW Samples
Accuracy
Matrix
DI Water
Humic and Fulvic
Acids
Ca and Mg
DW
GD
Concentration
1.4mg/L(a)
0.14mg/L
0.014 mg/L
0.0014mg/L
0.000 14 mg/L
0.14 mg/L
0.14 mg/L
0.14 mg/L
Number
Detected/Number
of Samples
3/3
3/3
3/3
3/3
0/3 (b)
6/6
6/6
12/12
100% (12 out of 12) of the contaminant-only PT samples were
positive.
False Positives
Three false positive responses were obtained. Two positive
responses were found for unspiked 1 mg/L humic and fulvic
acids. One replicate for unspiked OH DW returned a positive
result.
False Negatives
Precision
No false negative results were obtained for spiked PT and DW
samples.
90% (19 out of 21) of the sample sets showed consistent results
among the individual replicates within that set.
(a) Lethal dose.
(b) Not used in accuracy calculations because samples are at or below level of consistent negative response.
35
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Table 7-4. Aldicarb Summary Table
Parameter
Qualitative
Results
Contaminant-
Only PT
Samples
Interferent PT
Samples
DW Samples
Accuracy
Matrix
DI Water
Humic and Fulvic
Acids
Ca and Mg
DW
Aldicarb
Concentration
260 mg/L (a)
26 mg/L
2.6 mg/L
0.26 mg/L
0.026 mg/L
26 mg/L
26 mg/L
26 mg/L
Number
Detected/Number
of Samples
3/3
3/3
3/3
3/3
3/3
6/6
6/6
12/12
100% (15 out of 15) of the contaminant-only PT samples were
positive.
False Positives
Four false positive responses were obtained. Three positive
responses were found across unspiked 1 mg/L and 5 mg/L
humic and fulvic acids. One positive response was found for
unspiked 250 mg/L Ca and Mg samples.
False Negatives
Precision
No false negative results were obtained for spiked PT and DW
samples.
86% (18 out of 21) of the sample sets showed consistent results
among the individual replicates within that set.
Lethal dose.
36
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Table 7-5. Dicrotophos Summary Table
Parameter
Qualitative
Results
Contaminant-
Only PT
Samples
Interferent PT
Samples
DW Samples
Accuracy
Matrix
DI Water
Humic and Fulvic
Acids
Ca and Mg
DW
Dicrotophos
Concentration
1400 mg/L (a)
140 mg/L
14 mg/L
1.4 mg/L
0.14 mg/L
26 mg/L
26 mg/L
26 mg/L
Number
Detected/Number
of Samples
3/3
3/3
3/3
3/3
3/3
2/6
5/6
12/12
100% (15 out of 15) of the contaminant-only PT samples were
positive.
False Positives
Five false positive responses were obtained. Positive
responses were found for all replicates of the unspiked
250 mg/L Ca and Mg samples. One positive response was
found for the unspiked 50 mg/L Ca and Mg samples. One
other positive response was found for unspiked NY DW.
False Negatives
Five false negative results were obtained for spiked PT and
DW samples. All three replicates of the spiked 5 mg/L humic
and fulvic acid samples and one replicate of the spiked 1 mg/L
humic and fulvic acid samples returned negative results. One
spiked 50 mg/L Ca and Mg sample was also negative.
Precision
81% (17 out of 21) of the sample sets showed consistent
results among the individual replicates within that set.
w Lethal dose.
37
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Operational Factors:
Technical Operators
The OP/C Screen Kit was operated by one Battelle technician throughout testing with the
pesticides and a different Battelle technician throughout testing with chemical agents. The
technicians were trained by the vendor in the operation of the test kit. Both technicians had
extensive laboratory experience. The instructions provided with the kit were color-coded. The
colors on the dropper bottles helped to guide the operator through the testing and made using
multiple test solutions easier. The caps on the sample test tubes were difficult to remove. It also
seemed that the dropper bottles did not consistently deliver the same size droplet. The
instructions indicate that the samples should incubate for 15 to 30 minutes at various points
throughout testing; however, during the initial training phase of the verification test, it was
determined that the samples had to incubate for 30 minutes to achieve the correct results.
Overall, the OP/C Screen Kit was straightforward and easy to use. The OP/C Screen Kit needs
to be refrigerated until use, and then all of the reagents must come to room temperature before
they can be used. Three of the reagents used in testing must be prepared before they can be used.
Up to eight sets of duplicate samples can be tested at the same time using one OP/C Screen Kit.
Overall, it took the technical operators an average of 94 minutes to test seven samples. The
operators were able to test between one and five OP/C Screen Kits a day with four to eight
samples per kit.
Non-Technical Operators
Unspiked DI water samples were tested on the OP/C Screen Kit by a non-technical operator both
in and not in PPE. The non-technical operator was trained in the use of the kit by a technical
operator who had been trained by the vendor. Removing the dropper tips for the OP/C Screen
Kit dropper bottles was difficult to do in and out of PPE. Also, when transferring drops to the
tubes during testing, it was difficult to see the drops through the SCBA mask. The 100 |j,L
pipettes supplied with the OP/C Screen Kit were slightly difficult to handle while wearing gloves
as part of the PPE. The vendor recommends the use of a laboratory pipettor for use in the field.
Using the provided work station box to hold the samples proved to be somewhat problematic as
it was difficult to know which sample tubes had already been worked on and which had not.
Testing three MB samples in PPE using the OP/C Screen Kit took 82 minutes; six MB samples
without PPE took 86 minutes. The instructions for the OP/C Screen Kit indicate that the test
should be performed within a specific temperature range (70 ± 20°F) to achieve accurate results.
Presumably, this would be difficult for a first responder in the field to control. Also, the 15-
30 minute incubations that are performed at various points during the test would make it difficult
on the operator if they had to spend that time in PPR. The OP/C Screen Kit was felt to be not
very first-responder friendly for use in the field wearing PPE.
38
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Chapter 8
References
1. U.S. Army Center for Health Promotion and Preventative Medicine, USACHPPM
Technical Guide 230, Chemical Exposure Guidelines for Deployed Military Personnel,
January 2002.
2. Gosselin et al., Clinical Toxicology of Commercial Products. 5th edition, Baltimore, MD,
1984.
3. World Health Organization, The WHO Recommended Classification of Pesticides by
Hazard and Guidelines to Classification: 2004, 2005.
4. EPA-600-R-93/100. EPA Method 180.1. Turbidity (Nephelometric), Methods for the
Determination of Inorganic Substances in Environmental Samples. 1993.
5. American Public Health Association, et al. Standard Methods for Examination of Water and
Wastewater. 19th Edition. 1997. Washington D.C.
6. EPA 600/4-79/020 Method 150.1. pH, ElectrometricMethod.. 1982.
7. EPA 600/R-94/111 Method 200.8. Determination of Trace Metals by Inductively Coupled
Plasma - Mass Spectrometry. 1994.
8. EPA 600/4-79/020 Method 130.2. Hardness, Total (mg/L as CaCO3) Titrimetric, EDTA.
1982.
9. EPA 600/R-95/131. EPA Method 524.2. Purgeable Organic Compounds by Capillary
Column GC/Mass Spectrometry. Methods for Determination of Organic Compounds in
Drinking Water, Supplement III. 1995.
10. EPA 600/R-95/131. EPA Method 552.2. Haloacetic Acids andDalapon by Liquid-Liquid
Extraction, Derivatization and GC with Electron Capture Detector. Methods for the
Determination of Organic Compounds in Drinking Water, Supplement III. 1995.
11. Quality Management Plan (QMP) for the ETV Advanced Monitoring Systems Center,
Version 5.0, U.S. EPA Environmental Technology Verification Program, Battelle,
Columbus, Ohio, March 2004.
39
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12. Test/QA Plan for Verification of Enzymatic Test Kits, Battelle, Columbus, Ohio,
September 2005.
13. Battelle, SOP HMRC-IV-118-05: Standard Operating Procedure for the Determination of
CA in Wastewater.
14. Battelle, Standard Operating Procedure for Analysis of Water Extracts for Type I Analytes
by Liquid Chromatography/Mass Spectrometry, Version 1, January 2004.
15. Battelle, Standard Operating Procedure for Extracting and Preparing Water Samples for
Analysis of Dicrotophos, Mevinphos, and Dichlorovos, Version 3, March 2005.
40
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