EPA/600/R-17/394 | September 2017
www.epa.gov/homeland-security-research
United States
Environmental Protection
Agency
&EPA
Assessment of Solution Application
Methods for Decontamination of Surfaces
Contaminated with Pesticides
Office of Research and Development
Homeland Security Research Program

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Assessment of Solution Application Methods
for Decontamination of Surfaces Contaminated
with Pesticides
Lukas Oudejans, Ph.D.
National Homeland Security Research Center
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, NC 27711
Barbara Wyrzykowska-Ceradini, Ph.D.,
Eric Morris, and
Alexander Korff
Jacobs Technology, Inc.
Research Triangle Park, NC 27709

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Disclaimer
The U.S. Environmental Protection Agency (EPA), through its Office of Research and Development's
(ORD's) National Homeland Security Research Center (NHSRC), funded and managed this investigation
through Contract No. EP-C-15-008, work assignments (WAs) 1-074 and 2-074 with Jacobs Technology,
Inc. (Jacobs). This report has been peer and administratively reviewed and has been approved for
publication as an Environmental Protection Agency document. It does not necessarily reflect the views of
the Environmental Protection Agency. No official endorsement should be inferred. This report includes
photographs of commercially available products. The photographs are included for purposes of illustration
only and are not intended to imply that EPA approves or endorses the product or its manufacturer. EPA
does not endorse the purchase or sale of any commercial products or services.
Questions concerning this document or its application should be addressed to the principal investigator:
Lukas Oudejans, Ph.D.
Decontamination and Consequence Management Division
National Homeland Security Research Center
Office of Research and Development
U.S. Environmental Protection Agency
Mail Code E343-06
109 T.W. Alexander Drive
Research Triangle Park, NC 27711
Telephone No.: (919) 541-2973
E-mail Address: Oudeians.Lukas@epa.gov

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Acknowledgments
This research effort is part of the U.S. Environmental Protection Agency's (EPA's) Homeland Security
Research Program (HSRP) to evaluate decontamination cleanup procedures in the context of
remediation of building material surfaces contaminated with pesticides. Understanding the multifactorial-
way interactions between surface, pesticide, and decontaminant is critical for optimization of time- and
cost-effective decontamination approaches. The results of this work would inform responders,
governments, and health departments in their guidance development for remediation recommendations to
the general public.
This effort was directed by the principal investigator from the Office of Research and Development's
(ORD's) NHSRC, with support of a project team consisting of staff from across EPA. The contributions of
the following individuals have been a valued asset throughout this effort:
EPA Project Team
Lukas Oudejans, ORD/NHSRC (PI)
Paul Lemieux, ORD/NHSRC
Deborah McKean, Region 8
Kirsten Keteles, National Enforcement Investigations Center
Amy Mysz, Region 5
Alex Sherrin, Region 1
Larry Kaelin, Office of Land and Emergency Management (OLEM)/Consequence Management
and Advisory Division (CMAD)
Jacobs Technology Inc. Team
Abderrahmane Touati
Barbara Wyrzykowska-Ceradini
Eric Morris
Alexander Korff
U.S. EPA Technical Reviewers of Report
Richard Rupert, Region 3
Joseph Wood, ORD/NHSRC
U.S. EPA Quality Assurance
Eletha Brady-Roberts, ORD/NHSRC
Ramona Sherman, ORD/NHSRC
U.S. EPA Editorial Review
Joan Bursey

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Executive Summary
The U.S. Environmental Protection Agency (EPA) Homeland Security Research Program's
(HSRP's) purpose is to protect human health and the environment from adverse impacts of environmental
contamination (including terrorist incidents) by investigating the effectiveness and applicability of
remediation technologies for environmental response. Within the HSRP, EPA's National Homeland Security
Research Center (NHSRC) conducts research needed to identify methods and equipment that can be used
for decontamination of building surfaces contaminated with chemicals, including toxic industrial chemicals or
materials and chemical warfare agents (CWAs). This study focused on the laboratory-scale evaluation of
several decontamination cleanup procedures (DCPs) in the context of a remediation of building surfaces
contaminated with pesticides.
Pesticide misuse incidents for controlling bed bugs and other insects in indoor environments
continue to occur. These incidents include pesticide products not registered by the U.S. Environmental
Protection Agency (EPA) for indoor use or approved pesticide products that are improperly applied and/or
applied at concentrations that exceed the approved labeled rates. The bed bug epidemic is expected to
result in a growing number of pesticide misuse incidents. State and local agencies and EPA regional offices
are often called on to assist local communities in remediating homes and businesses following indoor
misapplications where pesticide levels might be unsafe.
Decontamination of surfaces contaminated with chemicals/pesticides is a complex process that
involves a combination of chemical and physical interactions between target contaminants, decontaminated
materials/surfaces, decontaminant, and, if applicable, also the cleaning media used to deliver the
decontaminant [1,2], Understanding these multifactorial interactions is critical for optimizing time- and cost-
effective decontamination approaches. Currently, there are no standard cleaning procedures to reduce
pesticide levels in affected structures. Field decontamination and cleaning practices vary widely, and there
is no agreement on cleanup and remediation procedures for the wide range of pesticides and surfaces
encountered, especially for indoor misuse or overuse situations.
In this study, decontamination testing was performed on a nonporous reference building material
(stainless steel coupon, 12 x 12 inch surface area) coated with chemical films of malathion
(organophosphorus pesticide) and carbaryl (carbamate pesticide) at a level of hundreds of milligrams per
square meter (mg/m2). Contaminated surfaces were cleaned using a commercially available solution
(EasyDECON® DF200; active ingredient activated hydrogen peroxide, H202) or a concentrated germicidal
bleach solution. Solutions were applied using various application techniques (spraying, wiping/scrubbing
and rolling-on). DCPs were tested in single- and multistep configurations; the single-step method had only
one application of contaminant followed by an one-hour dwell time of the decontaminant with the
contaminated surface. The multistep method used the same decontaminant applied twice with a cumulative
dwell time between decontaminant and contaminated surface of 28 hours (second application four hours
after first application). After the desired processing times were reached, test surfaces were rinsed with
deionized water and dried overnight. This process is similar to field remediation approaches where residual
decontaminant is rinsed off a surface.
Post-decontamination sampling of surfaces was performed using wipes dampened (semi-saturated)
with isopropyl alcohol. Following sampling, wipes were then sonicated in hexane at ambient temperature for
15 minutes. Resulting extracts were analyzed by gas chromatography/mass spectrometry (GC/MS).
Decontamination efficacy (DE) for each chemical-DCP combination was calculated using the means of
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chemical mass recovered from the surfaces of replicate test (decontaminated) coupons and the associated
set of positive control (not decontaminated) coupons. No characterization of liquid runoff was performed for
spray-on DCPs. Additionally, evaluations of the chemical transfer from the contaminated nonporous material
to cleaning media and chemical dissipation from selected surfaces were performed to provide an initial
estimate of how mechanical removal and natural indoor environmental attenuation processes only may
have contributed to the overall decontamination effectiveness.
The results of the various decontamination processes were variable, depending upon the chemical,
decontamination agent, and cleaning technique that was utilized. The decontamination solution with the
greatest reduction of pesticide surface concentration was the activated hydrogen peroxide formulation,
EasyDECON® DF200. This formulation resulted in nondetectable surface levels of malathion (or < 0.54
mg/m2) and a corresponding decontamination efficiency or DE rate of > 99.7%; this DE rate was calculated
by comparison with pre-decontamination surface loading of hundreds of mg/m2. EasyDECON® DF200
offered a high decontamination rate for carbaryl as well, with DE ranging from 94.8% to > 97.2% (initial
surface loading of hundreds of mg/m2). Only 13% of the test samples treated with various EasyDECON®
DF200-based application procedures showed detectable levels (>5.4 mg/m2) of carbaryl with a highest
average residual surface concentration of 11 mg/m2. EasyDECON® DF200 did not damage stainless steel
and caused no visible material incompatibilities, with post-drying residue easily removable with a final post-
decontamination water rinse.
All concentrated germicidal bleach-based DCPs reduced the malathion contamination from
hundreds of mg/m2 to nondetectable levels (< 0.54 mg/m2), with > 99.7% DE for malathion. For similar
surface concentrations of carbaryl, a maximum average decontamination efficacy of 95% was observed for
one multistep decontamination process, namely, the procedure that used a large industrial-grade synthetic
cleaning sponge that allowed the highest surface loading of decontaminant among tested procedures.
Other bleach-based decontamination procedures had DEs ranging from 63% to 83%, rendering the carbaryl
surface level to an average surface concentration of 30 to 66 mg/m2. In addition to a somewhat poorer
decontamination performance compared to EasyDECON® DF200, concentrated germicidal bleach caused
corrosion and discoloration on the stainless steel surface.
One of the most important considerations when selecting a decontaminant and associated
application method is the ability of such DCP to decrease the chemical burden to levels that are considered
safe for re-entry without specialized protective equipment, and ultimately for re-occupation of a building. The
laboratory determined DEs provide an assessment of the potential of these decontaminants and associated
application methods to reduce the chemical loading on the surface under controlled conditions of the test
(material, decontaminant, decontamination method, starting surface concentration of the chemical
contaminant, etc.). A DE does not provide information whether a safe level of residual chemical is left on the
surface. Here, human-health based screening levels were used for the calculation of risk-based cleanup
thresholds for malathion and carbaryl, similarly to how these would be established during an actual
response. Since there are no EPA regulatory values for surface cleanup goals, risk-based cleanup goals are
determined on a site- and situation-specific basis. The method referenced here is based upon the
information presented in "World Trade Center Indoor Environment Assessment: Selecting Contaminants of
Potential Concern and Setting Health-Based Benchmarks" [3], It is important to note that these
recommendations are not legally binding on any U.S. EPA program and should be interpreted as
suggestions that program offices or individual exposure assessors can consider and modify as needed.
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For malathion, the estimated child and adult, noncancer, nonporous material surface cleanup
thresholds using a conservative target hazard quotient (THQ) [4] of 0.1 are 0.3 and 1.7 mg/m2, respectively.
These threshold values are lower (for child) and higher (for adult) than the non detectable (< 0.54 mg/m2)
malathion surface concentrations. Decontamination with bleach or EasyDECON® DF200 using any of the
DCPs tested here would have led to acceptable residual pesticide levels for adults. The quantification limit
for malathion in this study is too high to determine whether the surface cleanup threshold for a child would
have been reached with either decontaminant.
For carbaryl, the noncancer child human health risk-based cleanup threshold for nonporous
surfaces and using a conservative THQ=0.1 was estimated to be 1.5 mg/m2 (8.5 mg/m2 for a human adult).
When using EasyDECON® DF200, one of the thirty test samples across all DCPs resulted in approximately
two times higher residual surface concentrations than the derived noncancer child human health risk-based
cleanup threshold for nonporous surfaces (11 mg/m2). For bleach, only the multistep DCP4 (use of a
cleaning sponge on the surface) reduced carbaryl levels to an average level of <10 mg/m2, which is still
above the human-health (child and adult) risk-based cleanup thresholds for nonporous surfaces. In this
laboratory study, the use of germicidal bleach resulted in residual carbaryl surface concentrations that
always exceed the estimated health risk-based cleanup threshold values.
The supplemental tests on the natural indoor attenuation of selected pesticides showed slow
dissipation (e.g., high persistence) of carbaryl and malathion from nonporous surfaces, with a less than
twenty percent reduction of surface chemical loading observed after 46 hours of post-contamination contact
time. A more permeable, semi-porous substrate initially evaluated in this study, painted drywall, showed a
high permeation-based uptake of malathion and carbaryl, with surface concentration of target pesticides
decreased by approximately 90% (as compared to analogous surface-bound levels reported for nonporous
materials). Therefore, no further surface decontamination studies were conducted with the drywall coupons
due to the lack of effective sampling methods for such semi-porous contaminated materials. Extraction of
the pesticide from this material into an organic solvent was considered but not deemed practical considering
the size (12x12 inches) of the coupons.
The results from the "chemical uptake by cleaning media"-tests suggest that effectiveness of
evaluated DCPs should be attributed mostly to chemical reactivity of the decontaminants. However,
selected cleaning processes, especially the processes with high liquid decontaminant volume, can remove
contamination solely by water via mechanical scrubbing and/or wiping steps. The transfer of contaminant to
liquid waste was minimal for DCPs with mechanical removal steps, with a maximum of 10% of the total
amount of chemical transferred to runoff.
IMPACT OF STUDY
This study demonstrated that chemical neutralization-based processes that employ a more
technologically advanced formula of oxidizers (e.g., EasyDECON® DF200), including addition of activators
and/or surfactants, was more advantageous than bleach for surface decontamination of stable and water-
insoluble pesticides. In addition, EasyDECON® DF200 was less damaging to sensitive surfaces than bleach
and resulted in less post-decontamination waste, thereby offering an economic advantage. The addition of a
mechanical cleaning step, especially one that delivers a high surface loading of solution, is desirable for
remediation of challenging chemicals, as it showed reduction of contamination even while using non-
chemically active cleaning solutions like water. The natural attenuation of high concentration pesticides
under ambient indoor environmental conditions does not provide an expedient reduction of chemical films
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from nonporous substrates. The low post-contamination surface concentration observed for semi-porous
materials after a 30 min contact time was attributed to significant (more than 90%) permeation of pesticides
into subsurface layers of the semi-porous test materials, potentially causing reduced susceptibility of
absorbed chemicals to non-invasive/non-destructive decontamination technologies.
LIMITATIONS OF STUDY
This study involved the determination of the efficacy of various decontamination applications at a
bench scale level and should lead to further research that would address the following elements that were
excluded in this effort:
•	With the emphasis on the determination of the efficacy towards neutralization of the targeted
pesticide, this effort did not address the possible formation of toxic decontamination byproducts,
which is important considering the use of malathion as one of the targeted pesticides that may
degrade to malaoxon, an oxidation byproduct of equal or higher toxicity than malathion.
•	All materials were clean and prepared specifically for this study. Hence, the study did not address
the impact of dirt and grime or imperfections on the decontamination efficacy when cleaning these
surfaces.
•	Pesticides are typically applied using their commercially available technical formulation. The
presence of, e.g., water and co-solvents in such formulations may alter the fate and transport of
these pesticides, especially into a semi-porous material. However, it is likely that the
decontamination efficacy against the neat pesticide applied here as a thin film can be extrapolated
to the decontamination efficacy of the same pesticide in a technical solution, especially when such
a solution has dried after application of the pesticide product.
•	Calculation of the decontamination efficacy assumes equal sampling efficiencies of the
chemical/pesticide prior to decontamination (positive control) and post-decontamination (test
coupon). A lower sampling efficiency at low surface concentrations may bias the calculated
decontamination efficacies high.
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Table of Contents
Disclaimer	ii
Acknowledgments	iii
Executive Summary	iv
Figures 	x
Tables 	xii
Acronyms and Abbreviations	xiv
1.0.	Introduction	1
1.1.	Project Objectives	1
2.0. Experimental Approach	3
2.1.	Test Facility	3
2.2.	Experimental Design	3
3.0. Materials and Methods	4
3.1.	Preparation of Test Coupons	4
3.2.	Target Chemicals	4
3.3.	Contamination of Coupons	5
3.4.	Test Setup	7
3.5.	Method Development Tests	8
3.5.1.	Sampling and Extraction for Surface Samples	8
3.5.2.	Optimization of Chemical Delivery to Surface Samples	9
3.5.3.	Persistence and Uptake of Chemicals by Test Coupon Materials	11
3.5.4.	Chemical Uptake by Cleaning Media and Transfer to Liquid Effluents	12
3.6.	Decontamination Tests	13
3.6.1.	Preparation of Decontamination Solutions	13
3.6.2.	Decontamination Procedures	14
3.6.2.1.	Cleaning Media	14
3.6.2.2.	Test Matrix	19
4.0 Sampling and Analysis Methods	22
4.1.	Sample Process Design for Single- and Multistep Testing	22
4.2.	Surface Sampling and Extraction Methods	26
4.3.	Liquid and Solid Waste Sampling and Extraction Procedures	28
4.4.	Preparation of Samples for Analysis	29
4.5.	Instrumental Analysis	29
4.6.	Data Reduction Procedures	34
4.6.1.	Chemical Concentration in Extract Calculations	34
4.6.2.	Decontamination Cleanup Efficacy Calculations	34
5.0. Results	36
5.1.	Persistence and Uptake of Chemicals by Nonporous and Semi-Porous Materials	36
5.2.	Surface Decontamination Efficacy	39
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5.3.	Residual Pesticides and Cleanup Thresholds 	46
5.4.	Transfer of Pesticide to Cleaning Media and Liquid Waste	48
6.0. Quality Assurance/Quality Control	51
6.1.	Test Equipment Calibration	51
6.2.	Data Quality Results for Critical Measurements	51
7.0. Summary	53
References	55
Appendix A: Supporting Information	57
Appendix B: Wipe Sampling Procedure	71
Appendix C: Method Development for Liquid Waste Extraction	75
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Figures
Figure 2-1. General experimental scheme and timeline	3
Figure 3-1. Master Performance Pro dual-action gravity-feed airbrush	6
Figure 3-2. Contamination spray pattern	6
Figure 3-3. Airbrush application of a malathion solution on stainless steel and chemical film post-
application	7
Figure 3-4. Stainless steel and painted drywall coupon assembly readied for testing	7
Figure 3-5. Assembled test setup with nebulization shield placed around test box	9
Figure 3-6. Hand-held pressurized sprayer	14
Figure 3-7. Cleaning-grade hand-held spray bottle	15
Figure 3-8. Absorbent cleaning cloth	15
Figure 3-9. Perforated synthetic wash sponge	16
Figure 3-10. Paint roller cover	16
Figure 3-11. DCP1 through DCP5 application of decontaminant using various cleaning media and
resulting appearance of the TC surface	18
Figure 4-1. Day 0 experimental design and sample flow for single- and multistep DCPs: contamination of
coupons and surface sampling of PCs	22
Figure 4-2. Day 1 experimental design and sample flow for single-step DCPs: application of
decontaminant and water rinse	23
Figure 4-3. Day 1 experimental design and sample flow for multistep DCPs: application and re-application
of decontaminant	24
Figure 4-4. Day 2 experimental design and sample flow for single-step DCPs: surface sampling of TCs.25
Figure 4-5. Day 2 experimental design and sample flow for multistep DCPs: application of water rinse... 26
Figure 4-6. Day 3 experimental design and sample flow for multistep DCPs: surface sampling and
extractions of TCs and PB	26
Figure 4-7. Example of surface wipe sampling of stainless steel in horizontal orientation	27
Figure 5-1. Malathion surface concentration overtime on nonporous material, stainless steel	36
Figure 5-2. Carbaryl surface concentration overtime on nonporous material, stainless steel	37
Figure 5-3. Malathion surface concentration overtime on semi-porous material, painted drywall	38
38
Figure 5-4. Carbaryl surface concentration overtime on semi-porous material, painted drywall	38
Figure 5-5. Malathion decontamination efficacy (%±SD) for single- vs multistep DCPs	44
Figure 5-6. Carbaryl decontamination efficacy (%+SD) for single- vs multistep DCPs	44
Figure 5-7. Appearance of the material surface after multistep treatment with bleach (A) and EasyDecon®
DF200 (B)	45
Figure 5-8. Post cleanup surface concentrations of malathion versus calculated human health risk-based
cleanup thresholds - THQ: target hazard quotient	47
Figure 5-9. Post cleanup surface concentrations of carbaryl versus calculated human health risk-based
cleanup thresholds - THI: target hazard index	48
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Figure 5-10. Expended cleaning materials generated during decontamination of an approximate area of
12 ft2 using three types of cleaning media	49
Figure 5-11. Malathion post-cleanup surface, liquid and solid waste amounts for all mechanical cleaning
media; % contribution calculated based on 1A LOQ	50
Figure 5-12. Carbaryl post-cleanup surface, liquid and solid waste amounts for all mechanical cleaning
media; dashed bars - no quantification, % contribution calculated based on 1A LOQ	50
Figure B-1. Folding wipe for sampling the first wiping pathway (horizontal)	71
Figure B-2. Horizontal wiping pathway	72
Figure B-3. Folding wipe for sampling the second wiping pathway (vertical)	72
Figure B-4. Vertical wiping pathway	72
Figure B-5. Folding wipe for sampling the third wiping pathway (diagonal)	73
Figure B-6. Diagonal wiping pathway	73
Figure B-7. Folding wipe for sampling the fourth pathway (perimeter)	74
Figure B-8. Perimeter wiping pathway	74
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Tables
Table 3-1. Specifications of building materials	4
Table 3-2. Physical and chemical properties of malathion and carbaryl	5
Table 3-3. Experimental parameters for surface contamination, wipe sampling and extraction optimization
tests	8
Table 3-4. Chemical surface loading of PCs (decontamination tests)	10
Table 3-5. Samples for persistence and uptake of chemical by test material	12
Table 3-6. Uptake of chemical by cleaning media and transfer to liquid effluent test	13
Table 3-7. Decontamination solutions	13
Table 3-8. Average surface loadings of decontaminant solutions and water rinses for different cleaning
media	17
Table 3-9. Test Matrix for Malathion Decontamination Testing	20
Table 3-10. Test Matrix for Carbaryl Decontamination Testing	21
Table 4-1. Wiping media, wetting solvent, and wetting solvent volume for surface sampling	27
Table 4-2. Instrumental parameters and conditions for GC/MS analyses of malathion (EMSL Analytical,
Inc.)	30
Table 4-3. Instrumental parameters and conditions for GC/MS analyses of carbaryl (EMSL Analytical,
Inc.)	31
Table 4-4. Instrumental parameters and conditions for GC/MS analyses of carbaryl (EPA OSL)	31
Table 4-5. QC checks for instrumental analyses performed by subcontracting laboratory	32
Table 4-6. The initial and continuing laboratory proficiency results	33
Table 5-1. Malathion and carbaryl surface concentrations on stainless steel and painted drywall over
three contact times tested	36
Table 5-2. Single- and -multistep bleach decontamination test results for malathion on stainless steel.... 40
Table 5-3. Single- and -multistep EasyDECON® DF200 decontamination test results for malathion on
stainless steel	41
Table 5-4. Single- and -multistep bleach decontamination test results for carbaryl on stainless steel	42
Table 5-5. Single- and -multistep EasyDECON® DF200 decontamination test results for carbaryl on
stainless steel	43
Table 6-1. Instrument Calibration Frequency	51
Table 6-2. Acceptance Criteria for Critical Measurements and Corresponding Test Results	52
Table A-1. Experimental parameters for malathion decontamination with bleach (single-step procedure.... 58
Table A-2. Experimental parameters for malathion decontamination with bleach (multistep procedure) ..59
Table A-3. Experimental parameters for carbaryl decontamination with bleach (single-step procedure	60
Table A-4. Experimental parameters for carbaryl decontamination with bleach (multistep procedure)	61
Table A-5. Experimental parameters for malathion decontamination with EasyDECON® DF200 (single-step
procedure	62
Table A-6. Experimental parameters for malathion decontamination with EasyDECON® DF200 (multistep
procedure)	63
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Table A-7. Experimental parameters forcarbaryl decontamination with EasyDECON® DF200 (single-step
procedure	64
Table A-8. Experimental parameters for carbaryl decontamination with EasyDECON® DF200 (multistep
procedure)	65
Table A-9. Calculated risk-based surface cleanup thresholds for malathion and carbaryl	66
Table A-10. Concentration of malathion in cleaning media (solid waste), liquid waste, and post- cleanup
surface concentration - all mechanical cleaning media (DCP deployed using water only)	69
Table A-11. Concentration of carbaryl in cleaning media (solid waste), liquid waste, and post-cleanup
surface concentration - all mechanical cleaning media (DCP deployed using water-only)	70
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Acronyms and Abbreviations
AChE	acetylcholinesterase
BL	bleach, blank
°C	degrees centigrade
CC	continuous calibration
cm	centimeters)
CMAD	Consequence Management and Advisory Division
COC	chain of custody
COTS	commercial-off-the-shelf
CS	control spike
CT	contact time
DCP	decontamination cleanup procedure
DE	decontamination efficacy
df	film thickness
Dl	deionized
DQI	data quality indicator
DT	dwell time
DUP	duplicate injection
EC	end check
EPA	U.S. Environmental Protection Agency
ft	foot / feet
GC	gas chromatography or gas chromatographic
GC/MS	gas chromatography/mass spectrometry
h	hour(s)
HPLC	high performance liquid chromatography
HSRP	Homeland Security Research Program (EPA)
ICAL	initial calibration
ICV	Initial Calibration Verification
in	inch
IPA	isopropyl alcohol
IS	internal standard
ISO	International Organization for Standardization
LCS	laboratory control spike
LCSD	laboratory control spike duplicate
LOQ	limit of quantitation
m	meter(s)
m1	square meter(s)
mg	milligram(s)
min	minute(s)
mL	milliliters)
mm	millimeters)
NCP	National Contingency Plan
NHSRC	National Homeland Security Research Center
NIOSH	National Institute for Occupational Safety and Health
NIST	National Institute of Standards and Technology
OLEM	Office of Land and Emergency Management

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OP
organophosphorus/organophosphate
ORD
Office of Research and Development (EPA)
OSL
Organic Support Laboratory (EPA)
oz
ounce(s)
Pa
Pascal
PB
procedural blank (coupon)
PC
positive control (coupon)
psi
pounds per square inch (pressure)
PTFE
polytetrafluoroethylene
QAPP
quality assurance project plan
QC
quality control
RH
relative humidity
RLV
reporting limit verification
RPD
relative percent difference
RSD
relative standard deviation
RTP
Research Triangle Park
SB
solvent blank
SD
standard deviation
TAT
turnaround time
TC
test coupon (contaminated and decontaminated)
THI
target hazard index
M9
microgram(s)
WA
work assignment

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1.0.	introduction
Pesticide misuse incidents for controlling bed bugs and other insects in indoor environments have
increased. These incidents include pesticide products not registered by the U.S. Environmental Protection
Agency (EPA) for indoor use or approved pesticide products that are improperly applied and/or applied at
concentrations that exceed the labeled rates. The bed bug epidemic is expected to result in a growing
number of pesticide misuse incidents. State and local agencies and EPA regional offices are often called on
to assist local communities in remediating homes and businesses following indoor misapplications where
pesticide levels might be unsafe. Currently, there are no standard cleaning procedures to reduce pesticide
levels in affected structures. Field decontamination and cleaning practices vary widely, and there is no
agreement on cleanup and remediation procedures for the wide range of pesticides and surfaces
encountered, especially for indoor misuse or overuse situations.
This report discusses the deployment of one-step and multistep cleaning procedures for
decontamination of a standard reference material (stainless steel) contaminated with two common
pesticides (malathion and carbaryl). Decontamination Cleanup Procedures (DCPs) tested used low-tech or
specialized oxidizing decontaminants (concentrated household germicidal bleach or hydrogen peroxide-
based EasyDECON® DF200), applied in various ways. DSPs ranged from spray-on application of the
decontaminant to application in combination with mechanical/physical removal (scrubbing). The goal of this
project is to provide field remediation specialists with more information on the effectiveness of various
decontamination solutions and related application methods for cleaning indoor surfaces contaminated with
pesticides.
1.1.	Project Objectives
The purpose of this project was to provide responding agencies with information on the
effectiveness of several decontamination and cleanup methods for high levels of pesticides on several
building materials. This research built on previous efforts under U.S. Environmental Protection Agency's
(EPA's) Homeland Security Research Program (HSRP) that determined conditions that led to effective
cleanup of building materials using specialized and commercial-off-the-shelf (COTS) cleaning products. This
work evaluated selected decontamination solution application methods that are being used in the field in
response to the misuse or overuse of pesticides.
This work had three primary objectives:
1.	Develop DCPs that are easily deployable in the field and can be used for remediation of indoor
building material surfaces contaminated with pesticides.
2.	Determine the feasibility and effectiveness of proposed approaches by measuring post-
decontamination surface pesticide residue concentrations in comparison to the mass of
pesticide on the positive control (non-decontaminated) coupons. The post-decontamination
surface pesticide concentrations would then be compared to derived health-based threshold
values.
3.	Compare remedial effectiveness of single step vs multistep protocols using specialized and
COTS cleaning media (e.g., wipes, sponges, cloths).
The secondary objectives were as follows:
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1.	Provide information on uptake of chemicals by various sampling media used for cleaning as
well as on the transfer of residual chemical to liquid effluents (decontamination solutions or
water rinses).
2.	Provide initial information on the amount of solid and liquid secondary waste generated from
various cleaning protocols.
3.	Assess (qualitatively) the impact of the decontaminant and application method on the material
4.	Compare residual pesticide levels post-decontamination against estimated cleanup threshold
levels
Results from this study characterize the performance versus practicality of different cleanup
techniques and remediation methods. This information will assist in creating guidelines for selection of the
best standardized approaches for remediation of pesticides in indoor environments.
2

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2.0.	Experimental Approach
2.1.	Test Facility
The experimental work was performed at the EPA's facilities in Research Triangle Park (RTP), NC.
Instrumental analyses of target chemicals in extracts and control samples were performed by an external
accredited chemical analysis laboratory (EMSL Analytical, Inc., Cinnaminson, NJ, USA) and by the in-house
EPA Organic Support Laboratory (OSL), located in RTP, NC.
2.2.	Experimental Design
This study evaluated five different approaches to deliver two types of decontaminants (concentrated
germicidal bleach and EasyDECON® DF200) to indoor nonporous and semi-porous surfaces (stainless
steel and painted drywall) that were contaminated with malathion or carbaryl. The decontaminant delivery
approaches consisted of spraying, scrubbing, rolling on, or wiping of the decontamination product, and
combinations thereof. For each procedure, a rinse step was incorporated (at various dwell times) after the
decontamination was completed as to remove residual decontaminant from a surface and to define the
decontamination time for the surface. A reapplication of decontaminant was tested as well for multiday
DCPs. The surface sampling of post-decontamination residual pesticides was performed after completion of
an overnight (24 h) drying step for each procedure. The schemes and general timelines for the single and
multistep test approaches are shown in Figure 2-1. Details of each cleanup procedure are described in
Sections 3.6.2 and 4.1. The sampling of a single set of positive controls (PCs) at a 30 min contact time (CT)
was based on the minimal dissipation of target chemicals observed during method development for CTs up
to 46 h (see Section 5.1)
¦	Preparation (cleaning) of coupons
¦	Preparation of pesticide solutions
¦	Contamination of coupons
¦	Sampling of PC; CT = 30 minutes (min)
•	At CT = 24 hour (h), application of decontamination solution to all test coupons: TCt1 and TCT2/3
•	At DT1 =1 h, application of rinse of TCt1 coupons, then allow overnight drying
•	At DT2 = 4 h, reapplication of decontaminant to TCT2/3 coupons; overnight dwell time
¦	After overnight drying, wipe sampling of TCt1 coupons and Day 2 extractions
¦	At DT3 = 24 h, application of rinse to TCT2/3, then allow overnight drying
¦	After overnight drying, wipe sampling of TCT2/3 coupons and PB and Day 3 extractions
¦	Preparation of samples for analysis and shipping of samples for analysis by subcontracting laboratory
PC - Positive control; CT - Contact time (time the chemical is in contact with a material surface); DT - Dwell time (time the
decontaminant is in contact with the material surface contaminated with pesticide; TCn - material test (decontaminated) coupon (TC)
for one application of decontaminant at DT 1 = 1 h; TCT2x - material test coupon for two applications of decontaminant at dwell times
DT2 =4 h plus DT3 = 24 h (equals 28 h); PB - Procedural blank
Figure 2-1. General experimental scheme and timeline.
3

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3.0. Materials and Methods
3.1. Preparation of Test Coupons
Two building materials (stainless steel and painted drywall) were selected for evaluation of cleanup
procedures (Table 3-1). Stainless steel was a reference material, selected for inertness and minimal
porosity and considered a good model for optimization of sampling approaches. Stainless steel was also
considered a surrogate for nonporous building surfaces. Painted drywall was selected as representative of a
semi-porous, permeable (painted/sealed) building material. The building material specifications are given in
Table 3-1. Due to substantial difficulties with recovery of target chemicals from the painted drywall surface
(results are described in Section 3.5.2.), this material was not subsequently used in decontamination tests.
Research that addresses phenomena specific to the (significant) chemical transfer into porous/semi-porous
materials and the efficiency of various decontamination methods for neutralization of chemicals that are
partially absorbed into a semi-porous building material (surrogate) is in progress.
Table 3-1. Specifications of building materials
Material
Description
Manufacturer/
Supplier Name/Location
Coupon Size,
L x W (in)
Material Preparation
Stainless
steel
Multipurpose stainless steel
(48 x 48 in), type 304, #2B
mill (unpolished), 0.036 in
thick
McMaster-Carr, Douglasville, GA,
USA
14x14*
Cut into coupons and remove any
lubricant/grease from shearing
with acetone. Wipe dry.
Immediately before use, remove
particles and dust by wiping clean
with acetone and then water.
Wipe dry.
Painted
drywall
1/2 in x 4 foot (ft) x 8 ft drywall
panel primed with KILZ®
latex primer and painted with
premium 100%acrylic latex
interior flat paint in white
National Gypsum Company,
Charlotte, NC, USA/ Lowe's,
Mooresville, NC, USA; KILZ® Latex
Primer, Masterchem Industries, Santa
Ana, CA, USA; Behr, Santa Ana, CA,
USA/Home Depot, Atlanta, GA, USA
14x14*
Cut into coupons. Remove
particles by wiping clean with
water and wipe dry.
* Actual test area was center 12x12 inches (in) or 929 cm2
Stainless steel coupons were cut to the correct length and width from larger sheets using heavy-
duty power hydraulic shears. Painted drywall panels were pre-cut to desired dimensions using a table saw.
The edges were finished using two-inch joint tape and joint compound applied over the tape using a putty
knife. After the joint compound cured, any rough spots were removed using a sanding block. Coupons were
then primed, sanded and painted using latex-based primer and 100% acrylic latex interior flat paint (Table 3-
1). All coupons were cleaned prior to testing using procedures described in Table 3-1.
3.2. Target Chemicals
The pesticides used to evaluate DCPs were malathion and carbaryl. Malathion is an
organophosphorus (OP) insecticide widely used in agriculture, outdoor pest control, and residential
landscaping. Carbaryl is a carbamate insecticide that is commonly used in gardens, commercial agriculture,
and forestry. Both insecticides have been misused indoors in improper responses related to the current bed
bug epidemic.
A malathion analytical standard was purchased from Chem Service (Chem Service, Inc., West
Chester, PA, USA; product # N-12346-500MG; purity: 99.5%). A carbaryl analytical standard was
purchased from Sigma-Aldrich (Sigma-Aldrich Co. LLC, St. Louis, MO, USA; product # 32055-250MG;
4

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purity 99.9%). The relevant physical and chemical properties of malathion and carbaryl are summarized in
Table 3-2.
Table 3-2. Physical and chemical properties of malathion and carbaryl
Property*
Malathion
Carbaryl
CAS Registry Number
121-75-5
63-25-2
Molecular weight
330.4
201.2
Formula
C10H19O6PS2
C12H11NO2
Density (g/cm3) at 20 °C
1.23
1.20
Physical form at 20 °C
Liquid
Solid
Vapor pressure
4.0x10-5 mm Hg at25°C
1.5x10-6 mm Hg at 25 °C
Solubility in water
0.143 g/L
0.04 g/L
Log Kow
2.36-2.89
2.36
*Data from https://oubchem.ncbi.nlm.nih.ciov (last accessed September 2017)
The target surface chemical concentrations in this study were based on field studies on wipe
sampling of indoor household surfaces after the misuse of malathion and carbaryl in residences, which have
shown a maximum concentration of 4.46 and 24.2 micrograms per square centimeter (pg/cm2) for malathion
and carbaryl, respectively; the concentration targets per 12 in x 12 in test area on each coupon were then
approximately 4 and 24 milligrams (mg) per surface area of 929 cm2, yielding theoretical contamination
levels in tens to hundreds of milligrams per square meter (mg/m2) range. Chemicals were applied onto the
test coupon (TC) as a chemical film using an airbrush-based application method described in Section 3-3.
3.3. Contamination of Coupons
Pesticide solutions were applied to coupon materials using an airbrush tool to form a thin film of
chemical on the coupon surface. Solutions were prepared using procedures developed in previous research
efforts [5] by dissolution of neat chemicals in organic solvents. Briefly, neat chemicals were dissolved in high
performance liquid chromatography (HPLC)-grade solvent to produce a mg/mL concentration nebulization
solution, then mixed using a vortex mixer and finally mixed via sonication for approximately 30 seconds.
Malathion was dissolved in ethanol at 6 mg/mL, and carbaryl was dissolved in acetone at 8 mg/mL. The
concentrations and volumes of nebulization solutions were delivered experimentally to allow deposition of
the chemical amount at the target surface concentration levels (Section 3.5.2). The optimized nebulization
methods accounted for losses related to overspray and settling of the chemical cloud on the walls of the
spraying shield, as well as losses of airborne chemical solutions due to high air flow in the chemical hood;
the latter effect was mitigated but not completely removed by the use of a nebulization (or spraying) shield
(Figure 3-5 in Section 3.5.2).
The accuracy and precision of preparation of spiking solutions was assessed for each experimental
batch by analysis of control spike (CS) samples (see Section 4.5 for results of analyses of control spikes).
TCs were cleaned using acetone and water and wiped dry, then contaminated with target chemicals using
the procedure described below.
5

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Figure 3-1. Master Performance Pro dual-action gravity-feed airbrush.
A Master Performance Pro dual-action gravity-feed airbrush with a 0.2-millimeter (mm) nozzle (Item
No. MAS G-233-SET, TCP Global, San Diego, CA), shown in Figure 3-1, was used for the thin-film
application of malathion and carbaryl solutions onto the surface of the coupons. This airbrush tool is
equipped with solvent-resistant needle packing and can be used with organic solvents.
The air supply was regulated using the airbrush compressor air pressure regulator gauge equipped
with a water trap moisture filter, with the pressure regulator set to 25 pounds per square inch (psi). Prior to
each use, the airbrush tool was purged with 5 milliliters (ml.) of the target solvent (ethanol for malathion and
acetone for carbaryl). Then, the airbrush barrel was filled with 5 ml_ of pesticide solution (malathion in
ethanol at 6 mg/mL or carbaryl in acetone at 8 mg/mL). A clean coupon was placed inside a plastic spraying
shield, and pesticide solution was sprayed onto the coupon surface using slow sweeping motions; spraying
started at the top left corner of the coupon and continued from left to right/top to bottom in a swiping motion,
as shown in Figure 3-2
Figure 3-2. Contamination spray pattern.
The spraying pattern was replicated until the reservoir was empty. Start and stop time of spraying
was recorded. Figure 3-3 shows the application of the chemical solution onto the stainless steel surface
(left) and the chemical film visible on the coupon surface post-application (right - the example shown is the
malathion chemical film).
6

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Figure 3-3. Airbrush application of a maiathion solution on stainless steel and chemical film post-application.
After nebulization of the chemical was completed, each contaminated coupon was gently
transferred horizontally by holding onto the edges into an individual pre-cleaned test box (dimensions: 18 in
x 18.75 in x 6.25 in; Stor-N-Slide square box with lid, product # 491530; IRIS USA, Inc., Pleasant Prairie,
Wl, USA) to allow for a simulated (indoor) weathering period/contact time; weathering was performed under
normal ambient laboratory conditions of approximately 22 °C and 25% relative humidity (RH) (averages
typical for early winter/spring months when testing was performed). Test boxes were cleaned using
laboratory-grade detergent solution, then v/iped with acetone and water and wiped dry.
3.4. Test Setup
Method development (Section 3.5) and decontamination testing (Section 3.6) were performed in a
chemical safety hood. Each contaminated coupon was placed in an individual pre-cleaned test box
(specifications and cleaning procedures in Section 3.3). Coupons were stored in closed test boxes during
the simulated weathering pre-decontamination phase to reduce evaporation due to the high air flow
conditions inside the chemical safety hood. Immediately prior to decontamination, contaminated stainless
steel coupons were placed horizontally on pre-cleaned latex spacers to allow collection of liquid waste.
Contaminated painted drywall coupons for vertical orientation (most common orientation in indoor setting)
testing were secured in pre-cleaned custom-made coupon holders. Figure 3-4 shows examples of stainless
steel and painted drywall coupon assemblies readied for horizontal or vertical testing.
Figure 3-4. Stainless steel and painted drywall coupon assembly readied for testing.
7

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Details of each decontamination procedure that was tested are given in Sections 3.6.2. and 4.1.
During the post-decontamination phase (dwell time of 1 h to 28 h, followed by a rinse step and overnight
drying [24 h]), coupons were stored in the chemical hood in open test boxes (Section 4.1 discusses
experimental details of single- and multistep experimental procedures, including procedure-specific
processing and drying times). After drying, coupons were sampled using methods described in Section 4.2.
3.5. Method Development Tests
3.5.1. Sampling and Extraction for Surface Samples
For surface sampling and wipe extraction efficacy tests, all test surfaces were coated with solutions
of target chemicals using the procedure described in Section 3-3 and placed in the same type of pre-
cleaned test box that was used during the decontamination testing. After a short contact time of the
chemical (CT=30 minutes (min) with the surface, wipe samples were collected and extracted using the
procedures described in Section 4.2.
The wetting solvent used for sampling optimization was isopropyl alcohol (IPA) (certified ACS,
Fisher Chemical, Waltham, MA; product # Ah16-4 UN1219), and this solvent was selected based on
previous research efforts [6] over dichloromethane as IPA is less prone to evaporation and is less
destructive to the surface. The wetting solvent volume was 3 mL per wipe (Cotton Twill wipes, MG
Chemicals Ontario, Canada; Part No. 829-4x4), resulting in semi-saturation of the wipe. Post-sample
collection, wipes were extracted and prepared for analysis as described in Section 4.4. Each test set
consisted of three TCs and one procedural blank; there was one solvent blank and one control spike sample
per test day per chemical. Initial optimization of surface sampling was performed in the horizontal orientation
only. The test matrix is shown in Table 3-3.
Table 3-3. Experimental parameters for surface contamination, wipe sampling and extraction
optimization tests
Chemical/Test Material
Target
Chemical
Concentration
(mg)a
Wiping
Medium
Typeb
Number of
Wipes per
Coupon0
Wetting
Solvent
Type
Volume
(mL)
Extractio
Solvent
Type
i
Volume
(mL)
Malathion/stainless steel
4
Cotton twill wipe
3
Isopropyl alcohol
3
Hexane
50
Malathion/painted drywall
4
Cotton twill wipe
3
Isopropyl alcohol
3
Hexane
50
Carbaryl/stainless steel
24
Cotton twill wipe
3
Isopropyl alcohol
3
Hexane:Acetoned
50
Carbaryl/pai nted drywall
24
Cotton twill wipe
3
Isopropyl alcohol
3
Hexane:Acetoned
50
aPer test area of 12 in x 12 in (929 cm2)* See Section 4.1 for detailed product information,c Three wipes per coupon collected and extracted as
a composite sample,d 10:1 v/v
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3.5.2. Optimization of Chemical Delivery to Surface Samples
Three rounds of airbrush delivery method optimization for malathion and carbary! were performed.
Optimization to reach target surface concentrations involved changing the concentration of the nebulization
solution and airbrush fill volume (3 to 36 mg/mL at 4 to 8 mL fill volume), as well as introduction of a
nebulization shield that prevented disruption of the nebulization cloud during airbrush application, as shown
in Figure 3-5.
Figure 3-5. Assembled test setup with nebulization shield placed around test box.
After three rounds of method optimization (data not shown), malathion results for the nonporous
reference material (stainless steel) were within project-specific acceptance criteria of 60-140% of the target
surface concentration target with an average recovery of 4.7 ± 0.30 mg per coupon (target concentration = 4
mg ± 1.6 mg per coupon). Meanwhile, the average recovery of carbaryl (at 95 ± 15.2 mg) was
approximately four times higher than the surface concentration target of 24 ± 9.6 mg per coupon. The
elevated surface delivery rate/surface concentrations for carbaryl could have been due to higher settling
rates (compared to malathion). Nebulized carbaryl solutions were observed to have formed prominent
(visible) clouds with airborne-particulate-like characteristics that, after settling, were producing powder-like
surface chemical films. In comparison, the malathion chemical clouds seemed to have the finer translucent
chemical droplet characteristics and ultimately formed an oily sheen film on the surface. Additional method
optimization for the carbaryl delivery amount was not performed due to the project time constraints. The
concentration of carbaryl in the nebulization solution was subsequently reduced from 36 mg/mL to 8 mg/mL
to account for the higher recovery of carbaryl, and the solution with the lower concentration was then used
in follow-on decontamination testing without further optimization of the target surface concentration.
Importantly, optimized methods resulted in chemical surface concentrations at the desired milligrams per
square meter (mg/rrr) level (Section 3-2) for both pesticides (results are provided in Table 3-4).
Results for chemical surface loading of stainless steel positive control coupons (from test-day-
specific batches of decontamination test samples) are given in Table 3-4, below. These results indicate that
the optimized airbrush nebulization method provided a reproducible delivery of high-surface-concentration
(pesticide) chemical films on a nonporous material, characterized by low intra- and inter-test variability
(relative standard deviation [RSD] < 30%) for the reference nonporous material (stainless steel).
9

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Table 3-4. Chemical surface loading of PCs (decontamination tests)
Chemical
Malathion
Carbaryl
Material
Stainless steel
IDa
mg/coupon
mg/m2
mg/coupon
mg/m2
Bleach Decontamination Tests DCP1 and DCP2 [Batch #1]
PC-1
14.0
151
18.6
201
PC-2
14.5
156
22.6
243
PC-3
16.0
172
12.8
138
Average (n=3)
14.8
160
18.0
194
SD
1.0
11.2
4.9
53.0
%RSD
7%
27% |
Bleach Decontamination Tests DCP3, DCP4 and DCP5 [Batch #2]
PC-1
15.5
167
19.3
208
PC-2
20.0
215
19.1
205
PC-3
18.0
194
20.4
220
Average (n=3)
17.8
192
19.6
211
SD
2.3
24.3
0.74
7.9
%RSD
13%
4% |
EasyDECON® DF200 Decontamination Tests DCP1 and DCP2 [Batch #3]
PC-1
13.0
140
19.0
204
PC-2
15.5
167
14.9
160
PC-3
15.0
161
19.8
213
Average (n=3)
14.5
156
17.9
193
SD
1.3
14.2
2.6
28.2
%RSD
9%
15% |
EasyDECON® DF-200 Decontamination Tests DCP3, DCP4 and DCP5 [Batch #4]
PC-1
10.0
108
18.2
196
PC-2
12.0
129
21.6
232
PC-3
17.5
188
18.7
201
Average (n=3)
13.2
142
19.5
210
SD
3.9
41.8
1.8
19.4
%RSD
29%
9% |
aDCP 1 through 5-Decontamination Cleanup Procedure; see Tables 3-2 and 3-3 for experimental
details. PC-positive control coupon; (1-3)- replicate sample number; SD = Standard deviation; RSD =
Relative standard deviation.
The analysis of airbrush application results performed by different personnel suggests that there is
an operator-related variation between tests. Here, the method development tests discussed in the first
paragraph of this section were performed by a different cross-trained analyst than the decontamination test-
10

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related PC contamination results in Table 3-4. This change in analyst resulted in unexpected significant
changes in amounts delivered to the surface via the airbrush. However, this change was not consequential
in terms of reaching the overall surface target threshold of milligrams per square meter (mg/m2). The
differences in surface loadings could be due to varying the distance of the airbrush tip from the coupon
surface, the ergonomic work-space arrangements (analyst sitting versus standing during application), or the
analyst-preferred (allowing best dexterity while maintaining safety) position of the chemical hood sash
(theoretically affecting the airflow around the nebulization shield). The position of the sash in this study was
at an operationally safe level to protect the breathing zone of the analysts, but the sash was not set to a
specific level or controlled throughout the entire testing. Other factors not yet identified could have
contributed to variation in surface loading. The results suggest that the nebulization procedure for inter-
related test subsets/batches should be performed by the same analyst and under the same operational
conditions in the chemical hood (e.g., using a fixed position of the safety sash, frequent calibration of the
flow/face velocity, etc.). Additionally, the intra-personnel cross-comparison checks should be completed
prior to experiments that are to be performed by multiple analysts.
The recovery of malathion from painted drywall during the method development tests was 0.42 ±
0.12 mg per coupon (or 9% of the chemical amount recovered from stainless steel). The recovery of
carbaryl from painted drywall was 11% of the recovery from stainless steel (10.9 ± 1.96 mg per coupon).
These lower recoveries from painted drywall may have been due to migration of the pesticide solution into
the semi-porous painted drywall material, with the consequent inaccessibility of the target chemical for
surface wipe sampling and potentially the reduced susceptibility of permeated chemicals to
decontamination. Similar low recoveries from semi-porous materials have been reported for OP chemical
warfare agents [6], Therefore, decontamination testing was not performed on painted drywall material.
There is a continued need for the development of (wipe) sampling methods that can sample and/or extract
(residual) chemical agent from a semi-porous material. As mentioned earlier, the phenomena of the
chemical permeation into semi-porous materials and optimization of decontamination strategies for
permeated persistent chemicals are currently being studied under a separate research effort.
3.5.3. Persistence and Uptake of Chemicals by Test Coupon Materials
As described in the previous section, the CT for the pesticides ranges from 25 h (single step DCP;
CT = 24 h plus DT1 =1 h) to 52 h (multistep DCP; CT = 24 h plus DT2 = 4 h plus DT3 = 24 h). The
evaporation and/or other losses (e.g., indoor UV light-related degradation) were not expected to be
significant as previous research [7] demonstrated that both carbaryl and malathion are highly persistent on
stainless steel surfaces. However, some amount of pesticide was expected to transfer into the semi-porous
test materials during the chemical-surface CT.
Independent tests for the persistence and uptake of the chemicals by the test materials were
executed prior to the decontamination testing to verify whether a single time point could function as a single
set of PCs. PCs would be spiked at the same time as the test coupons. However, extraction by wipe
sampling would occur at a different CT that would consider the workload on Day 1 and Day 2 of each test.
The persistence and uptake tests consisted of several measurements of the surface concentration of the
pesticides taken after 30 min, 24 h, and 48 h (Table 3-5). The latter time was reduced to 46 h due to
constraints in the work schedule. Each test consisted of three sets of three TCs and one PB. All PBs were
sampled only at total contact time corresponding to the maximum contact time for this study (46 h).
11

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Coupons were contaminated in the horizontal position, and tests were performed in the horizontal and
vertical orientations for stainless steel and painted drywall, respectively.
Table 3-5. Samples for persistence and uptake of chemical by test material
Chemical/Surface
Contact Time

30 min
24 h
46 h
Malathion/stainless steel
TC = 3
TC = 3
TC = 3, PB = 1
Malathion/painted drywall
TC = 3
TC = 3
TC = 3, PB = 1
Carbaryl/stainless steel
TC = 3
TC = 3
TC = 3, PB = 1
Carbatyl/pai nted drywall
TC = 3
TC = 3
TC = 3, PB = 1
TC- test coupon, PB- procedural blank.
Each set of TCs was contaminated with the chemical using the procedure described in Section 3.3.
The coupons were then placed in the same type of pre-cleaned transparent test box that was used during
the decontamination testing; boxes remained closed in the same manner as during the pre-decontamination
phase of testing to mitigate the effect of high air flow and air exchange rates in the chemical safety hood, as
the ventilation rates in the chemical hood were not considered representative of normal air
exchange/ventilation rates in indoor settings. After the prescribed CT (Table 3-5) was completed for each
set of coupons, sampling and extraction of the coupons took place following the procedures described in
Sections 4.1 and 4.2. Samples were prepared for analysis as described in Section 4.2. Results of the tests
for uptake of chemical by test material are given in Section 5.1.
3.5.4. Chemical Uptake by Cleaning Media and Transfer to Liquid Effluents
Physical removal of chemicals from the test material surfaces was expected for scrubbing-, wiping-
and to a lesser extent, roll-on-based approaches using cloths, sponges, and paint rollers (DCPs 3, 4, and 5
described in Section 3.6.2). For these DCPs, the uptake of chemical by the cleaning media (from the
reference material, stainless steel) was tested using a single-step method for a contact time of 30 minutes
(Table 3-5). The chemical uptake by cleaning media was not studied for painted drywall due to overall low
surface recovery observed for the semi-porous material as discussed in Section 3.5.2. Each test consisted
of three TCs complemented by one material- and chemical-specific PB. Tests were performed in the
horizontal orientation only. All cleaning media were pre-wetted with deionized (Dl) water to decouple
physical removal of chemicals by various types of cleaning media from the neutralizing action of the
decontaminants. The amount of water needed to saturate each sampling medium corresponded to the
wetting volume of decontaminant that had been determined prior to testing and varied from 50 to 150 mL of
water, depending on type of cleaning media (media-specific wetting volumes are given in Section 3.6.2.1).
There was no water rinse in this test.
Each set of stainless steel TCs was contaminated with pesticide using the procedure described in
Section 3.3 and then placed in the same transparent test boxes used during the decontamination testing.
Surfaces were decontaminated with water only, using procedures described in Section 3.6.2.1. The liquid
12

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run-offs were collected and extracted using procedures described in Section 4.3. After the conclusion of the
coupon cleaning, the expended cleaning media were collected (as solid waste) for extraction, and surface-
wipe samples were collected to allow determination of chemical remaining on each coupon surface after
deployment of the mechanical cleaning step. Surface samples were collected and extracted using methods
described in Section 4.2.
The test matrix for the uptake of pesticide by cleaning media and transfer to liquid effluent is given
in Table 3-6, below. Results are summarized in Section 5.3.
Table 3-6. Uptake of chemical by cleaning media and transfer to liquid effluent test
Cleaning Medium Type
Cotton Cloth
Sponge
Paint Roller
Type of Sample
Malathion/Stainless Steel

Number of Samples
Solid waste3
TC = 3, PB = 1
TC = 3, PB = 1
TC = 3, PB = 1
Liquid wasteb
TC = 1(C), PB = 1
TC = 1(C), PB = 1
TC = 1(C), PB = 1
Surface wipe0
TC = 3, PB = 1
TC = 3, PB = 1
TC = 3, PB = 1
Type of Sample
Carbaryl/Stainless Steel

Number of Samples
Solid waste3
TC = 3, PB = 1
TC = 3, PB = 1
TC = 3, PB = 1
Liquid wasteb
TC = 1(C), PB = 1
TC = 1(C), PB = 1
TC = 1(C), PB = 1
Surface wipe0
TC = 3, PB = 1
TC = 3, PB = 1
TC = 3, PB = 1
8 Expended cleaning media;b Composite sample of run-offs collected during cleaning;c Wipe samples collected post-cleaning;
three wipes per coupon collected and extracted as a composite sample (C); TC- test coupon, PB- procedural blank
3.6. Decontamination Tests
3.6.1. Preparation of Decontamination Solutions
Decontaminants used in this study have proven efficacious for both malathion and carbaryl in
previous research efforts [7], General information and properties of decontamination solutions are given in
Table 3-7.
Table 3-7. Decontamination solutions
Solution
Manufacturer/Supplier Name/Location
Active Ingredient
pH Range
EasyDECON® DF200
Envirofoam Technologies, Pooler, GA,
Hydrogen peroxide
9.6-9.7

USA/lntelagard, Lafayette, CO, USA


Clorox® concentrated germicidal bleach
The Clorox® Company, Oakland, CA
Hypochlorite ion/
11-12
(8.25%sodium hypochlorite)

hypochlorous acid

Fresh batches of EasyDECON® DF200 solution were prepared daily through proportional mixing as
per the manufacturer's instructions in amounts sufficient for testing (e.g., to make 2 L of decontamination
solution, 950 mL of EasyDECON® DF200 Part 1 was mixed with 1010 mL of EasyDECON® DF200 Part 2,
and then 40 mL of EasyDECON® DF200 Part 3 was added). After mixing, the manufacturer recommends
13

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the use of the EasyDECON® DF200 Fortifier Test Kit to test the stability of the EasyDECON® DF200 final
blend. This test (a "Go/No Go" test) measures the percentage of active ingredient and instills confidence
that the decontamination solution is effective and ready to use. The ongoing evaluations that occurred prior
to use also included pH measurements of the finished blend (target pH range: 9.6-9.9). Results are
discussed in Section 6.0 (Table 6-2). Concentrated Clorox® germicidal bleach was used as is (no
preparation was needed); no evaluation of the concentrated germicidal bleach solution was performed. Dl
water was used for post-decontamination rinses.
3.6.2. Decontamination Procedures
Various decontamination cleanup procedures were evaluated for their ability to decontaminate
pesticides deposited onto test surfaces. Tested DCPs involved several cleaning techniques, including spray-
on-only methods (with no mechanical removal step) and methods that allowed a potential physical removal
of contamination by the cleaning medium (wiping/scrubbing and roll-on applications). Transfer of
contamination to the cleaning media was tested for the latter category (Section 3.5.3). For each application
method, two general decontamination approaches were tested:
1.	A simplified/expedient (single-step) approach: The chosen decontamination solution was
applied once and allowed to interact with the material for one hour. Then, test surfaces were rinsed, allowed
to dry overnight, and sampled for residual pesticides.
2.	A multi-application/multi-day (multistep) approach: The chosen decontamination solution
was applied twice within the first four hours of the decontamination process and allowed to interact with the
material for a total of 24 hours. Then, test surfaces were rinsed, allowed to dry overnight, and sampled for
residual pesticides.
3.6.2.1. Cleaning Media
Decontamination solutions were applied using commercially available equipment (hand-held
sprayer) and basic household-use supplies (cleaning-grade spray bottle, general-purpose cleaning cloth,
general-purpose cleaning sponge, and paint roller). The product information and specifications of cleaning
media that were used in this study are given below:
1. Hand-Held Pressurized Sprayer. The spray gun (MeterJet™ Gunjet Spray Gun Kit, Forestry
Suppliers, Inc., Jackson, MS, USA; Figure 3-6) used in this study can deliver a metered volume of
spray ranging from 1 to 16 mL with ± 2% accuracy. This spray gun was used successfully for
applications of numerous cleaning agents in previous research [8],
Figure 3-6. Hand-held pressurized sprayer
2. Cleaning-Grade Hand-Held Spray Bottle. A durable industrial sprayer bottle (Figure 3-7) was
purchased from a national supplier (Lowe's Companies, Inc., Mooresville, NC, USA; 32-ounce (oz)
14

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plastic spray bottle; Lowe's Item No, 366843, Model No. LOAPS30). This type of bottle is equipped
with a trigger sprayer with no adjustable spray pattern and is recommended by the manufacturer for
general household cleaning purposes, including application of concentrated formulas.
¦
A-
Figure 3-7. Cleaning-grade hand-held spray bottle.
3. Absorbent Cleaning-Grade Cloth. Cleaning-grade 100% cotton cloths (Figure 3-8), approximately
14 in x 17 in each, were purchased from a national supplier (ProLine 48-count terry towels; Lowe's
Companies, Inc., Mooresville, NC, USA; Lowe's Item No. 503439, Model No. T-99765). These
cloths are recommended by the manufacturer for multipurpose cleaning tasks. Each towel was
folded twice prior to wetting to allow better manageability during application of the decontamination
solution onto the 14 in x 14 in coupon.
TERRY
Figure 3-8. Absorbent cleaning cloth.
4. Perforated Synthetic Wash Sponge. Cleaning-grade polyurethane sponges (Figure 3-9), approxi-
mately 4.5 in x 7 in each, were purchased from a national supplier (ProLine polyurethane sponge;
Lowe's Companies, Inc., Mooresville, NC, USA; Lowe's Item No. 469322, Model No. K-56P). This
type of sponge is recommended by the manufacturer for multipurpose cleaning tasks. The sponge
product specifications were inspected for any added ingredients/additives prior to use; no additional
additives were noted. Sponges were precut in half using a precision blade pre-cleaned with ethanol
to allow easy folding for the subsequent large-volume extraction step (described in Section 4.3).
15

-------
fluTugg
Figure 3-9. Perforated synthetic wash sponge.
5. Paint Roller. Polyester regular paint roller covers and rollers (Figure 3-10), approximately 9 in
each, were purchased from a national supplier (Blue Hawk, Lowe's Companies, Inc., Mooresville,
NC, USA; Lowe's Item No. 299909, Model No. 1838181). This type of paint roller (with a 3/8 in nap)
is recommended by the manufacturer for use on smooth surfaces. Compatible roller handles were
purchased separately. Paint rollers were precut in half using a precision blade pre-cleaned with
ethanol to allow easy folding for the subsequent large-volume extraction step (described in Section
4.3).

¦amw'
ni!
Figure 3-10. Paint roller cover.
Decontaminant and water rinses were applied using step-specific cleaning media (Table 3-9 and 3-
10). The surface of the coupon was always cleaned using horizontal (left to right) overlapping strokes that
were applied from top to bottom of each coupon. Twenty rriL of decontaminant or water was pre-loaded for
pressurized sprayer application, based on a 20 x 1 mL spray pattern. Following daily calibrations with Dl
water, spray bottles were preloaded with 100 mL, and 20 mL of solution was delivered onto each coupon.
For other cleaning media, wetting volumes were delivered experimentally to allow a uniform saturated (but
non-dripping) wetting. The media wetting volumes were determined gravimetrically by weighing each dry
cleaning medium and then weighing the wetted medium again, before application onto the coupon surface.
A 100 mL of solution was used per sponge, 150 mL of solution was used per cotton cloth, and 50 mL of
solution per paint roller (pre-cut in half). All cleaning media were pre-loaded prior to testing and placed in
individual plastic bags, and bags were closed to avoid non-specific decontaminant losses. The
EasyDECON® DF200 pre-loaded cotton cloths heated significantly (~38 °C), and there was unidentified gas
build-up prompting venting of plastic bags prior to deployment. There were no other incompatibilities
observed between cleaning media and decontaminants.
Decontamination testing (spiking, decontamination application, and wipe sampling) was conducted
by one laboratory support person to iimit inter-personal variance. Decontamination technique vigor (i.e.,
media application pressure and velocity) mimicked typical household cleaning.
The consequent surface loadings (amount of decontaminant or rinse applied onto each coupon)
were determined gravimetrically by weighing each test box before and after application. Accuracy of the
scale was sufficient, to measure an absolute mass change of 1 g, an equivalent of approximately 1 mL of
16

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liquid decontaminant or water rinse. The average decontaminant and water (rinse) surface loading volumes
for each cleaning medium are given below in Table 3-8. Sample-specific results are given in Appendix A,
Tables A-1 through A-8.
Table 3-8. Average surface loadings of decontaminant solutions and water rinses for different
cleaning media.
Type of Decontarninant
Pressurized
Sprayer
Spray
Bottle
Cotton
Cloth
Cleaning
Sponge
Paint
Roller

Surface Loading per Test Coupon*

mL
±SD
mL
±SD
mL
±SD
mL
±SD
mL
±SD
Concentrated Germicidal Bleach
18.2
NA
18.7
0.83
3.41
0.43
24.7
6.7
4.2
1.4
EasyDECON® DF200
16.9
NA
17.3
0.73
6.02
1.58
22.3
8.7
6.3
3.8
Water rinse
20.0
NA
20.4
0.6
3.82
2.50
17.1
8.2
7.1
5.2
Calculated from gravimetic measurements of pre- and post-applications and specific gravities of decontaminants; for pressurized sprayer,
application was based on a 20 x 1 mL spray volume following daily calibrations with Dl water.
SD: Standard Deviation; NA: Not Applicable
Other test-specific experimental parameters for the single- and multistep procedures (contact times
for chemical weathering, dwell times for decontaminant processing) are given in Appendix A in Tables A-1
through A-8.
Figure 3-11 shows examples of decontamination solution application using different cleaning
procedures and post-application appearance of test surfaces (immediately post-application of
decontaminant). Examples shown are for EasyDECON® DF200 applications.
17

-------

1/*	1
/
(
/I
Figure 3-11. DCP1 through DCP5 application of decontaminant using various cleaning media and resulting
appearance of the TC surface
18

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3.6.2.2. Test Matrix
The decontamination test matrix is shown in Tables 3-9 and 3-10. Three decontaminated TCs were
used for each chemical for single- and multistep methods, three PC coupons per test per cleaning medium
(coupons contaminated with chemical that did not undergo decontamination), and one PB (coupon not
spiked with chemical that will undergo decontamination in the horizontal orientation). Additionally, one
control spike sample was prepared per test day to check for nominal concentration of spiking solution as
well as for ongoing laboratory proficiency testing; this sample was prepared as a direct spike of chemical
solution to hexane, at a level corresponding to 100% of the target surface concentration of chemical
expected in the final extract. Test matrices for malathion and carbaryl decontamination testing are
summarized in Tables 3-9 and 3-10, respectively; and sample process design for single- and multistep
testing is given in Section 4.1. Decontamination test results are given in Section 5.2.
19

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Table 3-9. Test Matrix for Malathion Decontamination Testing
Test ID
Procedure
Surface
Orientation
Decontaminant
Application of
Decontaminant
Water Rinse #1
Reapplication of
Decontaminant
Water Rinse #2
DCP1S-MA-SS-BL-PS-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Pressurized sprayer 1
Pressurized sprayer 2
No
No
DCP1S-MA-SS-BL-PS-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Pressurized sprayer 1
No
Pressurized sprayer 1
Pressurized sprayer 2
DCP1S-MA-SS-ED-PS-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Pressurized sprayer 1
Pressurized sprayer 2
No
No
DCP 1S-MA-SS-ED-PS-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Pressurized sprayer 1
No
Pressurized sprayer 1
Pressurized sprayer 2
DCP2S-MA-SS-BL-SB-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Spray bottle 1
Spray bottle 2
No
No
DCP2S-MA-SS-BL-SB-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Spray bottle 1
No
Spray bottle 1
Spray bottle 2
DCP2S-MA-SS-ED-SB-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Spray bottle 1
Spray bottle 2
No
No
DCP2S-MA-SS-ED-SB-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Spray bottle 1
No
Spray bottle 1
Spray bottle 2
DCP3S-MA-SS-BL-RG-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted cloth 1
Wetted cloth 2
No
No
DCP3S-MA-SS-BL-RG-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted cloth 1
No
Wetted cloth 1
Wetted cloth 2
DCP3S-MA-SS-ED-RG-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Wetted cloth 1
Wetted cloth 2
No
No
DCP3S-MA-SS-ED-RG-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Wetted cloth 1
No
Wetted cloth 1
Wetted cloth 2
DCP4S-MA-SS-BL-SP-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted sponge 1
Wetted sponge 2
No
No
DCP4S-MA-SS-BL-SP-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted sponge 1
No
Wetted sponge 1
Wetted sponge 2
DCP4S-MA-SS-ED-SP-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Wetted sponge 1
Wetted sponge 2
No
No
DCP4S-MA-SS-ED-SP-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Wetted sponge 1
No
Wetted sponge 1
Wetted sponge 2
DCP5S-MA-SS-BL-PR-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted paint roller 1
Wetted paint roller 2
No
No
DCP5S-MA-SS-BL-PR-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted paint roller 1
No
Wetted paint roller 1
Wetted paint roller 2
DCP5S-MA-SS-ED-PR-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Wetted paint roller 1
Wetted paint roller 2
No
No
DCP5S-MA-SS-ED-PR-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Wetted paint roller 1
No
Wetted paint roller 1
Wetted paint roller 2
MA-malathion; BL-bleach; ED-EasyDECON® DF200; DCP 1 to 5-Decontamination Cleanup Procedure 1 to 5; PS-pressurized sprayer; SB-spray bottle; RG-cotton chth; SP- sponge; PR-paint roller; S/ M-single or -multistep procedure.
20

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Table 3-10. Test Matrix for Carbaryl Decontamination Testing
Test ID
Procedure
Surface
Orientation
Decontaminant
Application of
Decontaminant
Water Rinse #1
Reapplication of
Decontaminant
Water Rinse #2
DCP1S-CA-SS-BL-PS-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Pressurized sprayer 1
Pressurized sprayer 2
No
No
DCP1S-CA-SS-BL-PS-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Pressurized sprayer 1
No
Pressurized sprayer 1
Pressurized sprayer 2
DCP1S-CA-SS-ED-PS-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Pressurized sprayer 1
Pressurized sprayer 2
No
No
DCP 1S-CA-SS-ED-PS-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Pressurized sprayer 1
No
Pressurized sprayer 1
Pressurized sprayer 2
DCP2S-CA-SS-BL-SB-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Spray bottle 1
Spray bottle 2
No
No
DCP2S-CA-SS-BL-SB-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Spray bottle 1
No
Spray bottle 1
Spray bottle 2
DCP2S-CA-SS-ED-SB-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Spray bottle 1
Spray bottle 2
No
No
DCP2S-CA-SS-ED-SB-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Spray bottle 1
No
Spray bottle 1
Spray bottle 2
DCP3S-CA-SS-BL-RG-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted cloth 1
Wetted cloth 2
No
No
DCP3S-CA-SS-BL-RG-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted cloth 1
No
Wetted cloth 1
Wetted cloth 2
DCP3S-CA-SS-ED-RG-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Wetted cloth 1
Wetted cloth 2
No
No
DCP3S-CA-SS-ED-RG-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Wetted cloth 1
No
Wetted cloth 1
Wetted cloth 2
DCP4S-CA-SS-BL-SP-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted sponge 1
Wetted sponge 2
No
No
DCP4S-CA-SS-BL-SP-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted sponge 1
No
Wetted sponge 1
Wetted sponge 2
DCP4S-CA-SS-ED-SP-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Wetted sponge 1
Wetted sponge 2
No
No
DCP4S-CA-SS-ED-SP-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Wetted sponge 1
No
Wetted sponge 1
Wetted sponge 2
DCP5S-CA-SS-BL-PR-1
S
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted paint roller 1
Wetted paint roller 2
No
No
DCP5S-CA-SS-BL-PR-4/24
M
Stainless steel
Horizontal
Concentrated germicidal bleach
Wetted paint roller 1
No
Wetted paint roller 1
Wetted paint roller 2
DCP5S-CA-SS-ED-PR-1
S
Stainless steel
Horizontal
EasyDECON® DF200
Wetted paint roller 1
Wetted paint roller 2
No
No
DCP5S-CA-SS-ED-PR-4/24
M
Stainless steel
Horizontal
EasyDECON® DF200
Wetted paint roller 1
No
Wetted paint roller 1
Wetted paint roller 2
CA—carbaryl; BL-bleach; ED-EasyDECON® DF200; DCP 1 to 5-Decontaminatbn Cleanup Procedure 1 to 5; PS-pressurized sprayer; SB-spray bottle; RG-cotton chth; SP- sponge; PR-paint roller; S/ M-single or -multistep procedure.
21

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4.0 Sampling and Analysis Methods
4.1. Sample Process Design for Single- and Multistep Testing
A multiday sample process/experimental design was used for each DCP test. The sample process
for single- and multistep decontamination testing is shown in Figures 4-1 through 4-6, respectively. Each
decontamination test was accompanied by collection of reference (non-decontaminated) PC coupons. A PB
was tested for each DCP deployed using the multistep method. The wipe sampling and extraction methods
are summarized in detail in Section 4.2.
Day 0:
Positive Controls
Weathering
wit itit tut
^
¦
¦ ¦ ¦
4 4 4
m m ¦.
Single-Step DCP Test Coupons
TC-2	TC-3
Multi-Step DCP Test Coupons + DCP Procedural Blank
TC-2	TC-3

4 4
4
4
4
Weigh Test
boxes
Add 50 mL of
extraction solvent
to extraction jars
i
[
I
*
Step 1. Contaminate TC and PC coupons:
5 mL of malathion or carbaryl solution nebulized
onto the surface of each coupon using air-brush
method; allow 30 min-long weathering of PCs.
Step 2a. Sample PCs:
Sample each PC with cotton twill wipes wetted
with 3 mL of solvent (3 wipes per coupon)
Step 2b. Allow weathering ofTCs:
Place each TC coupon in a clean secondary
container and weigh the test box; store closed in
thelume hood for 24 hours.
Step 3. Place the PC sampling twill wipes in
60m L jars. Add 50mL ofhexane or 10:1 (\/\^
hexane:acetone and sonicate for 15 min.
Transfer extract to storage yal.
Figure 4-1. Day 0 experimental design and sample flow for single- and multistep DCPs: contamination of
coupons and surface sampling of PCs.
22

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Day 1:
Single-Step DCPand rinse
Weigh
Test
boxes
TC-1 V
TC-2 \
TC-3
Prepare decontamination solution:
•	EasyDecon: permanufacturer instructions; preform a Go/No-go test and pH assessment.
•	Bleach: used as is.
Prepare decontamination solution and rinse application media:
•	Spray Gun: Calibrate and fill tank with solution
•	Spray Bottle: Fill bottle with -1 OOmL of solution
•	Sponge: Place sponge in bag and wet with 100mLofsolution
•	Cotton Rag: Place rag in bag and wet with 150mL of solution
•	Paint roller: Cut roller into two pieces with saw. Place roller in bag and wet with 50mL of solution
Weigh
Test
boxes
Weiqh
Test
boxes
TC-1 -
TC-2 V
Apply
decontamination
solution
Allow processing in the
chemical hood in open test
boxes(DT=1h)
Apply
water rinse
Allow drying in the chemical hood
in open test boxes(DT=24h)
I
\
I
Step 1. Apply decontamination solution
Open test boxes and apply media specific
decontamination solution. Weigh boxes.
Step 2. Allow processing:
Open boxes in chemical hood and allow to
process for DT=1 hour, Weigh boxes
Step 3. Apply water rinse:
Apply water rinse using same application
method asdecon application. Weigh boxes.
I
Step 4. Allow drying:
Allow drying in chemical hood for 24 hours.
Figure 4-2. Day 1 experimental design and sample flow for single-step DCPs: application of decontaminant
and water rinse.
23

-------
Day 1:
Multi-Step DCP Step 1 and 2
Weigh
Test
boxes
Prepare decontamination solution:
•	EasyDecon: per manufacturer instructions; preform a Go/No-go test and pH assessment.
•	Bleach: used as is.
Prepare decontamination solution and rinse application media:
•	Spray Gun: Calibrate and fill tank with solution
•	Spray Bottle: Fill bottle with -100mL of solution
•	Sponge: Place sponge in bag and wet with 100mL of solution
•	Cotton Rag: Place rag in bag and wet with 150mL of solution
•	Paint roller: Cut roller into two pieces with saw. Place roller in bag and wet with 50mL of solution
TC-1 >
TC-2 *
PB-1
Weigh
Test
boxes
Weigh
Test
boxes
TC-1 \
TC-2 V
TC-3
Apply
decontamination
solution
Allow processing in the
chemical hood in open test
boxes (DT=4h)
Reap plication of
decontamination
solution
Allow processing in the
chemical hood in open test
boxes (DT=24h)
I
I
\
Step 1, Apply decontamination solution
Open test boxes and apply media specific
decontamination solution. Weigh boxes.
Step 2. Allow processing:
Allow to process for DT=4 hours. Weigh
boxes.
Step 3. Re-application of decon solution:
Re-apply decontaminant using same
application method as decon application.
Weigh box.
Step 4. Allow overnight processing:
Allow to process for DT=24 hours. Weigh
boxes.
Figure 4-3. Day 1 experimental design and sample flow for muitistep DCPs: application and re-application of
decontaminant.
24

-------
Day 2:
Single-Step DCP Sampling
TC-1 V
TC-2 %
TC-3
X3 Wipes
Add 5D mL of
extraction solvent
to extraction jars

H ffl
A i L
1 ' i r
in ii



a
c
i a
\
4 \
a ¦
\
\
Step 1. WipeTCs with cotton twill wipes
wetted with 3 mL of solvent (3 wipes)
Step 3. Place twill wipes in 6QmL jars. Add
50mL of hexane or 10:1 hexane:acetoneand
sonicate for 15 min. Transfer extracts to
storage vial
Figure 4-4. Day 2 experimental design and sample flow for single-step DCPs: surface sampling of TCs.
25

-------
Day 2:
Mufti-Slap OCP rinsa
Wt*gh
Test
boxes
TC-1 \
TC-2 V
TC-3
W«»gh
Test
bo*#*
\
I I
Appty watarrinsa
Weatfeervhie open m fuma
hood Tor 24 hours
i
Sttp 1 *#*t ran*#
Weajh *.«ti».«es Appty water rmse ussrg urne
SCfltC4tor> rrHhTCl 3$ «Md
decomarwnalion Weigh test toies
Step 4. Alow crying
Alow d>y»"«) m tMmscai hoed for 24 tart
TM %
TC-2 %
Figure 4-5. Day 2 experimental design and sample flow for multistep DCPs: application of water rinse.
Day 3:
MulLi'SSep DCP Sampling
TM >
TC-3 >
XIWmi
te-j *
*
m

1
i
¦
I
¦ 11
i

& 1

%
0
3
0
Siep I WptTt* *9- ccfflont*i «npe»
«*at4 3 fH. Of |,3 wet* I
S6«3 FVKriwJ ftlc*ti^«yr*C|Prt to
SCri. o< **xan* or 10 1 xtirY* I^V)
*-$ VrKtb} 5gO& nul T'injV MT^ie !?
V£>'ir)t v *
Ml KtrLof
fts*«*»c&ofi?irt
Figure 4-6. Day 3 experimental design and sample flow for multistep DCPs: surface sampling and extractions
of TCs and PB.
4.2. Surface Sampling and Extraction Methods
This section summarizes types of wiping media, wetting solvents, and amount of wetting solvents
for all material-chemical combinations that were used for collection of pre- and post-decontamination
surface wipe samples, including PBs. The wipe sampling and extraction procedure was previously
evaluated for malathion and carbaryl. The procedure was recently evaluated for concentrations that are
typically seen in pesticide misuse applications [7], where the wetting solvent and its volume were optimized
for high concentrations of malathion and carbaryl (4 and 24 mg, respectively, per 12 by 12-in test area).
Wipe sampling methods were optimized prior to testing as described in Section 3.5.1. Table 4-1
26

-------
summarizes types of wiping media, wetting solvents, and amount of wetting solvent for all material-pesticide
combinations.
Table 4-1. Wiping media, wetting solvent, and wetting solvent volume for surface sampling
Chemical/Surface
Wiping Medium
Number of
Wipes
Wetting Solvent
Wetting Solvent
Volume*
Malathion/stainless steel
Cotton twill wipe
3
Isopropyl alcohol
3mL
Malathion/painted drywall
Cotton twill wipe
3
Isopropyl alcohol
3mL
Carbaryl/stainless steel
Cotton twill wipe
3
Isopropyl alcohol
3mL
Carbaryl/painted drywall
Cotton twill wipe
3
Isopropyl alcohol
3mL
*volume of wetting solvent per wipe
Each wipe was deployed using a four-step process consisting of a series of horizontal (Step 1,
Figure 4-7), vertical (Step 2, Figure 4-7), diagonal (Step 3, Figure 4-7) and perimeter (Step 4, Figure 4-7)
wiping strokes, where the wipe was folded over after each step (with contaminated side always inward). The
detailed procedure (presented in Appendix B) is based on an internal miscellaneous operating procedure for
wet wipe sampling of coupons. Figure 4-7 shows examples of wipe sampling on a horizontal reference
material (collection of first wipe out of a total of three used for sampling shown).
Figure 4-7. Example of surface wipe sampling of stainless steel in horizontal orientation.
After completion of sampling, three wipes resulting from wiping each coupon were placed in a pre-
cleaned 60- or 100-mL wide-mouth extraction jar with polytetrafluoroethylene (PTFE)-lined lids, for
composite extraction. Each jar received 50 ml_ of hexane (Optima™, HPLC/spectrophotometry, gas
chromatography/mass spectrometry (GC/MS) and pesticide residue analysis grade, Fisher Chemical,
product # H 303-4 UN1208), was capped and was transferred to the sonicator. Note that the hexane term
27

-------
refers to the mixture, as purchased, of n-hexane (45-60%), hexane (isomers) (15-40%) and cyclohexane
(3%). Wipe samples were extracted via sonication for 15 minutes. After extraction was completed, a 15-mL
aliquot of the extract was transferred to a 20-mL glass vial and refrigerated at 4 °C ± 2 °C until further
processing. The remainder of the sample extract was managed as laboratory waste. Sample preparation for
instrumental analysis is described in Section 4.4.
4.3. Liquid and Solid Waste Sampling and Extraction Procedures
This section summarizes the liquid waste (runoff) and solid waste (expended sponges, cloths and
paint rollers) sampling, and procedures used during tests for chemical uptake by cleaning media and
transfer to liquid effluents (described in Section 3.5.3).
Target chemicals from the liquid waste samples (generated in simulated DCP3, DCP4 and DCP5
procedures in which water was used instead of decontaminants; test procedure described in Section 3.5.3)
were extracted using a simplified liquid-liquid extraction procedure following the modified extraction
procedure described in EPA Method 3571 (Extraction of Solid and Aqueous Samples for Chemical Agents)
[9], The method performance for liquid-liquid extraction of water samples containing malathion was
optimized under other ongoing research efforts. A detailed summary of the method is given in Appendix C.
Good recoveries were observed for low concentrations (0.05 jjg/mL) of malathion from non-preserved and
preserved (with L-ascorbic acid, ethylenediaminetetraacetic acid) and non-pH-adjusted, and pH-adjusted
(with trisodium salt of potassium dihydrogen citrate) water-waste matrix spike samples (100% ± 15% SD
and 125% ± 3.9% SD, respectively; n=3 for treated and non-treated samples, respectively).
The above extraction method was checked for carbaryl recovery using Dl water samples spiked
with carbaryl at 0.2 |jg/ml_. Carbaryl degrades rapidly at pH > 7, with a half-life of approximately 10-17 days
at pH of 7 down to three hours for pH of 9 at 25 °C [10], If the aqueous samples containing carbaryl were at
pH > 7, they should be acidified to pH 4-5 with 0.1 N chloroacetic acid [11], In this study, the uptake by
cleaning media and transfer to liquid effluent experiments were performed using Dl water (pH less than 7);
there were no concerns about accelerated degradation of carbaryl. The recovery of carbaryl from (non-pH-
adjusted) control samples was 109% ± 1.7% SD (n=3). During testing, the pH of the liquid waste samples
collected was checked immediately after liquid waste samples were collected (recorded pH range was 4.0-
4.5, depending on the type of cleaning procedure/simulated DCP).
After determination of waste volume for each type of runoff collected (DCP3, DCP4 and DCP5),
liquid waste samples were transferred to a clean extraction vial, and an equal volume of hexane was added
to each sample (1:1 v/v liquid waste:hexane). Each sample was manually shaken for one minute. After the
aqueous and hexane layer separated, the entire hexane layer was carefully collected using a Pasteur
pipette and placed into a 15 mL test tube with graduated markings. The total extract volume was recorded.
The simulated liquid waste extracts did undergo dilution prior to analysis. One mL of hexane extract was
transferred into a 1.8 mL pre-labeled gas chromatographic (GC) amber glass screw-top vial. Samples were
refrigerated after preparation and remained refrigerated until prior to shipment to the subcontracting
laboratory for analysis. In addition, a 10 mL aliquot of the remaining extract was transferred to a 12 mL vial
and archived under the same conditions at 4 °C ± 2 °C.
Solid waste samples (expended sponges, cleaning cloths and paint rollers) were extracted using a
modified procedure that was optimized for extraction of cotton wipes from sampling (Section 4.2). The
modifications include the following:
28

-------
1.	Extraction solvent volume was increased tenfold to perform large volume extraction, with 1000
mL beakers used instead of small extraction jars. Each beaker was filled with 500 mL of hexane for
extraction of malathion, or hexane:acetone (10:1, v/v) for extraction of carbaryl.
2.	Due to the large volume of samples, the extraction time was extended to 30 minutes. The level of
the extraction solvent was marked using a permanent marker. The beakers were covered with
aluminum foil (Heavy Duty Aluminum Foil, Food Service Foil 627; Reynolds Consumer Products,
Lake Forest, IL, USA). The temperature of the water in the sonic bath was monitored and noted in
the laboratory notebook every five minutes, with some heating of the water bath observed (highest
recorded temperature after 30 minutes of sonication was 34.6 °C from the initial temperature of 20.7
°C at the beginning of extraction). The resulting losses in extraction solvent following sonication
were compensated by adding solvent to return to the same marked level. No losses were more than
10% for the large-volume extraction procedure. The evaporation-related losses of pesticides were
not systematically studied or monitored (e.g., by use of labeled pre-extraction surrogates spiked into
samples prior to extractions), but were considered to be negligible due to the minimal evaporation
rate and low volatility of the target pesticides.
Immediately after extraction was completed, the entire extract was quantitatively poured into
another clean beaker. After the aqueous layer separated from the organic layer, samples were prepared for
analysis. Due to the high volume of extraction solvent, most of the samples did not undergo dilution prior to
analysis. Only a small subset of samples, those analyzed for carbaryl by the EPA OSL (Section 4.5), were
diluted in hexane to concentrations that aligned with the dynamic GC calibration range (100-5000 ng/mL)
and spiked with Internal Standard (IS)/surrogate mix. For non-diluted samples, one mL of hexane extract
was taken from each secondary beaker and transferred into a 1.8-mL pre-labeled amber glass screw top
GC vial and prepared for shipment to the subcontracting laboratory for analysis. Samples were then
refrigerated prior to shipment to the subcontracting laboratory for analysis. In addition, a 10 mL aliquot of the
remaining extract was transferred to a 12 mL vial and archived at 4 °C ± 2 °C.
4.4.	Preparation of Samples for Analysis
Extracts generated from extraction of wipes (Section 4.2) and liquid and solid wastes (Section 4.3)
were prepared for analysis in 1,8-mL amber glass GC vials. Depending on the type of sample, extracts
underwent up to 20-fold dilution. An aliquot of raw extract was drawn using an appropriate size micropipette
and added to a GC vial filled with a premeasured amount of hexane (e.g., 50 microliters (|jL) of sample and
950 |jL of hexane, for a 20-fold dilution). The control spike samples were also diluted up to 20-fold. Other
extracts (PCs from non-reference (painted drywall) material, all decontaminated TCs, blanks, and liquid
waste extracts) were submitted to the subcontracting laboratory as is. A 1000-|jL aliquot of sample was
drawn from each extract using an electronic pipette and added to the GC vial. If analytical results were
outside calibration range, the analytical laboratory performed necessary dilutions and reported dilution
factors along with quality control (QC) data. The samples were refrigerated at 4 °C ± 2 °C or below prior to
shipment. All shipments were accompanied by the chain of custody (COC) form and were inspected by the
analytical laboratory upon receipt.
4.5.	Instrumental Analysis
Instrumental analyses were performed using modified National Institute for Occupational Safety and
Health (NIOSH) Method 5600 [12] by an accredited subcontracting laboratory, EMSL Analytical, Inc.
29

-------
(Cinnaminson, NJ, USA). Sample extracts were analyzed by means of GC/MS. Malathion was detected
using ions of mass 93, 125 and 173 (quantitation with ion of mass 173). Carbaryl was detected using ions of
mass 115 and 144; additionally, the ion of mass 144 of a positively identified thermo degradation product, 1-
naphthalenol, was also reported (quantitation with combined response for parent compound and degradation
product). The quantitation of carbaryl by the EPA OSL was also performed by GC/MS but under different
instrumental conditions. The EPA OSL did not observe thermo degradation of carbaryl/formation of 1-
naphthalenol. The quantitation of carbaryl was done using isotope dilution, with labeled carbaryl-13C6 (CLM-
4682-1.2, Cambridge Isotope Laboratories, Inc., Tewksbury, MA, USA) as internal standard and
phenanthrene-D10 as a surrogate compound (ERS-020-1.2ML, Internal Standards Mixture, Sigma-Aldrich Co.
LLC, St. Louis, MO, USA). The instrumental parameters and conditions for GC/MS analyses for both analytes
are given in Tables 4-2 through 4-4. Analysis by the EPA OSL was limited to carbaryl samples associated
with the chemical uptake tests described in Section 3.5.3.
Table 4-2. Instrumental parameters and conditions for GC/MS analyses of malathion (EMSL
Analytical, Inc.)
Parameter
Description/Conditions
Instrument
Agilent 6890 Gas Chromatograph equipped with Agilent 5973 Mass Selective Detector (Agilent
Technologies, Santa Clara, CA, USA)
Autosampler
Agilent 7683 Automatic Sampler (Agilent Technologies, Santa Clara, CA, USA)
Column
Rtx®-5Sil MS w/5 m Integra-Guard® column, 30 m x 0.25 mm I.D., 0.25 |jm film thickness; part no.
13623-124 (Restek Corporation, Bellefonte, PA, USA)
GC column program
100 °C initial temperature, hold 0 min, 15 °C/min to 250 °C, hold 5 min
Carrier gas flow rate
1.0 mL/min
Injection volume/type
1.0 [jL/splitless
Inlet temperature
250 °C
MS source temperature
230 °C
MS transfer line
270 °C
30

-------
Table 4-3. Instrumental parameters and conditions for GC/MS analyses of carbaryl (EMSL
Analytical, Inc.)
Parameter
Description/Conditions
Instrument
Agilent 6890 Gas Chromatograph equipped with Agilent 5973 Mass Selective Detector (Agilent
Technologies, Santa Clara, CA, USA)
Autosampler
Agilent 7683 Automatic Sampler (Agilent Technologies, Santa Clara, CA, USA)
Column
Rtx®-MS5 column, 30 m x 0.32 mm I.D., 0.50 |jm df; part no. 13439 (Restek Corporation, Bellefonte,
PA, USA)
GC column program
100 °C initial temperature, hold 0 min, 15 °C/min to 250 °C, hold 5 min
Carrier gas flow rate
1.0 mL/min
Injection volume/type
1.0 [jL/splitless
Inlet temperature
225 °C
MS source temperature
230 °C
MS transfer line
270 °C
Table 4-4. Instrumental parameters and conditions for GC/MS analyses of carbaryl (EPA OSL)
Parameter
Description/Conditions
Instrument
Thermo Trace 1300 Gas Chromatograph GC ISO™ Mass Spectrometer (Thermo Fisher Scientific, Inc.,
Waltham, MA, USA)
Autosampler
AS/A11310 Autosampler (Thermo Fisher Scientific, Inc., Waltham, MA, USA)
Column
DB-5,20 m x 0.25 mm I.D., 0.25 |jm df; part no. 13439 (Agilent, Santa Clara, CA, USA)
GC column program
80 °C initial temperature, 20 °C/min to 150 °C, 4 °C/min to 190 °C, 30 °C/min to 300 °C, final hold 2
min
Carrier gas flow rate
1.3 mL/min
Injection volume/type
1.0 [jL/splitless
Inlet temperature
150 °C
MS source temperature
200 °C
MS transfer line
200 °C
For EMSL Analytical, Inc., the calibration range of 1-100 jjg/mL for both analytes (seven-point
calibration curve; 1-10-20-40-60-80-100 jjg/mL) was used for initial calibration, with reporting limit
verification (RLV) and initial calibration verification (ICV) analyses performed at lowest and mid-calibration
level, respectively, prior to each analytical run. Due to instabilities in response of the 1 |jg/ml_ carbaryl
standard, this standard was excluded from calibration and average response factor calculations (six-point
curve was run prior to analysis, and quantitation was performed using two five-point curves depending on
sample concentration: 10-20-40-60-80 ug/mL (low-concentration curve, used for analysis of decontaminated
samples and blanks) and 20-40-60-80-100 ug/mL (high-concentration curve used for analysis of non-
decontaminated samples and control spikes at 100% target concentration). Additionally, analysis of the
laboratory control sample (LCS) and the laboratory control sample duplicate (LCSD) was performed prior to
each batch of samples. A continuous calibration standard at concentration mid-level was analyzed every ten
samples, with a calibration end check performed at the end of each analytical run. Additional QC samples
included duplicate injections of test samples and analysis of laboratory blanks. Samples with results below
31

-------
the lowest calibration point (i.e., 1 jjg/mL) were reported as less than the limit of quantitation (
-------
Table 4-6. The initial and continuing laboratory proficiency results
Target Chemical
Spike Control A
100% Target Concentration,
No Coupon*; n=5
Spike Control B
10% Target Concentration,
No Coupon*;n=5
Solvent Blank

Accuracy and Precision

EMSL Analytical, Inc.
Malathion (initial)3
95.0%±2.5%SD; RSD=2.6%
79.5%±3.1 % SD; RSD=3.9%
-------
4.6. Data Reduction Procedures
4.6.1.	Chemical Concentration in Extract Calculations
The GC/MS concentration results (|jg/mL) were converted to total mass of chemical per sample (mg
per sample) by multiplying by the extraction solvent volume and dilution factor (if applicable):
Ms = CsxVexDfx1000	(1)
where:
Ms = mass of chemical in sample (mg)
Cs = concentration (|jg/mL) from an individual replicate sample
VE = extraction solvent volume (mL)
DF = sample dilution factor prior to analysis (if any)
The percent recovery of the chemical from the QC samples (e.g., control spikes) was calculated
against theoretical chemical amount spiked into solution:
%Rqc = Cqc/(Vsp x SqA/j/Dp) x 100% (2)
where:
%Rqc = percent recovery for an individual QC sample (versus theoretical)
CQC = concentration (|jg/mL) from an individual replicate QC sample
VSp = volume of spike (mL)
Sc = concentration of chemical in spiking solution (8 mg/mL for carbaryl or 6 mg/mL for
malathion)
VT = total sample volume (mL)
Dp = sample dilution factor prior to analysis (if any)
The chemical mass (Ms) results used for decontamination efficacy calculations were not adjusted
for QC sample recovery (%Rqc).
4.6.2.	Decontamination Cleanup Efficacy Calculations
The decontamination cleanup efficacy was calculated using the mean of the chemical mass
recovered from the replicate TC and the mean chemical mass recovered from the associated set of PCs.
DE = (1 - xTCn/ xPCn) x 100% (3)
34
-------
where:
DE = mean decontamination efficacy (%)
xTCn = mean of chemical amount remaining on replicate TC (decontaminated) coupons (mg)
xPCn = mean of chemical amount remaining on replicate PC (non-decontaminated) coupons
(mg)
The mean decontamination efficacy along with the standard deviation was calculated as cumulative
decontamination efficacy (or resulting from application of all three procedural steps for each test). The
standard deviation of the efficacy was calculated by propagation of error using the standard deviation of the
average mass of agent remaining on the TCs and on the PCs. If the average mass of remaining agent on
the TC was found to be below the LOQ, the efficacy was calculated using the LOQ value and reported as
"greater than" this calculated value.
35
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5.0.	Results
5.1.	Persistence and Uptake of Chemicals by Nonporous and Semi-Porous
Materials.
The results for the persistence and uptake of chemicals by nonporous and semi-porous materials,
(experimental approach described in Section 3.5.2) for three chemical-surface-contact times tested (CTmin =
30 min, CTmid = 24 h, CTmax = 46 h) are given in Table 5-1, below.
Table 5-1. Malathion and carbaryl surface concentrations on stainless steel and painted drywall
over three contact times tested

Stainless Steel
Painted Drywall
Contact
Times
Mean
±SD
%RSD
Mean
±SD
%RSD

mg/m2
mg/m2
Malathion
CTmin=30 min
50.2
3.5
7.0%
4.5
1.3
28%
CTmid=24 h
59.4
4.0
6.7%
3.4
0.50
15%
-C
CO
ii
E
I—
o
46.5
6.6
14%
4.1
0.47
11%
Carbaryl
CTmin=30 min
1010
120
12%
117
21.1
18%
CTmid=24 h
1040
51.4
4.9%
125
37.3
30%
-C
CO
ii
E
I—
o
898
11.4
1.3%
98.4
7.7
7.9%
so
~S)
E
.2 60
"'H
Malathion surface concentration on nonporous material overtime
(CT=30 min to 46 hours)
a>
o
c
o
o
0)
o
3
CO
i
40
20
0 4 S 12 16 20 24 20 32 36 40 44 40
CT (hours)
Figure 5-1. Malathion surface concentration overtime on nonporous material, stainless steel.
36
-------
No significant surface dissipation of target chemicals from nonporous materials was observed
during 24 hours; the average concentration of malathion and carbaryl at CTmid was actually slightly higher
than chemical film surface concentration measured for CTmin subsets (Table 5-1). The decrease of malathion
and carbaryl concentration observed between 24-h and 46-h contact times (Table 5-1, Figure 5-1) was,
however, statistically significant (p<0.05 and p<0.01, respectively).
E
o>
E
£
O
'•M
5
£
0)
O
£
O
o
0)
o
1=
3
<0
Carbaryl surface concentration on nonporous material overtime
(CT=30 min to 46 hours)
1200
1100
1000
900
800
12 16 20 24 28 32
CT (hours)
36
40
44
48
Figure 5-2. Carbaryl surface concentration overtime on nonporous material, stainless steel.
The low dissipation rates of target pesticides from reference stainless steel material, <20%
reduction of chemical surface concentration for approximately two-day contact times are in line with
pesticide stability on nonporous surfaces reported in other laboratory and field studies addressing short and
long-term building surface persistence of semivolatile compounds with low vapor pressures [13], The nerve
agent VX, an OP compound structurally similar to malathion, was recently reported to be short-term stable
on a stainless steel surface contaminated with chemical at a level of milligrams per square meter, with
surface loadings reduced by average 11 and 24 percent at 24 and 72 hours post-contamination [14], For
comparison, vapor pressures, which are associated with the volatility of a chemical, of VX and malathion at
25 °C are 0.117 Pascals (Pa) and 0.0053 Pa, respectively [15], Carbaryl has a lower volatility than
malathion (0.00020 Pa) [15] and hence, is even less prone to evaporation-related losses; the literature-
reported evaporation-related dissipation of the carbaryl (applied to a soil surface) was estimated to be less
than 1% after 50 days post-application [16], It should be emphasized that pesticide degradation in indoor
environments is likely to be accelerated by moisture, sunlight and/or microorganisms, similar to the
degradation in the outdoor environment [17], None of these factors was contributing to pesticide breakdown
on the clean and relatively inert surfaces used in this laboratory study.
37
-------
Analysis of surface concentrations of target pesticides from a representative semi-porous material
(painted drywall) was performed in parallel to testing of the nonporous stainless steel (results are in Table 5-
1 and are summarized in Figures 5-3 and 5-4). The results indicated that uptake of target chemicals
occurred rapidly, with only approximately ten percent of the chemical mass remaining on the surface after
30 minutes post-application (as compared to the equivalent reference material subset; Table 5-1). Over
time, the surface-available fraction of the chemical remained relatively constant and did not show a
statistically significant surface dissipation trend (Figures 5-3 and 5-4).
8.0
O)
E
o 6.0
§ 4.0
c
o
o
<1> 2.0
o
£
3
« 0.0
Malathion surface concentration on porous material overtime
(CT=30 min to 46 hours)
12 16 20 24 28 32 36 40 44 48
CT (hours)
Figure 5-3. Malathion surface concentration overtime on semi-porous material, painted drywall.
Carbaryl surface concentration on porous material overtime
£
O)
E
c
o
c
o
o
c
o
o
-------
The rapid uptake of persistent organic chemicals is often reported in the context of chemical
transport and fate prior to decontamination [2,14], Since the goal of this study was optimization of
decontamination procedures, the decontamination experiments for semi-porous materials were not
performed, due to uncertainties in the mechanism of action of decontaminants against permeated chemical
agents, including a potential reverse transport of contaminants to the material surface post-decontamination.
Studies investigating optimization of decontamination procedures for neutralization of chemical agents
absorbed into semi-porous building materials, including possible optimization of decontamination solution
delivery methods to subsurface layers of semi-porous materials, are ongoing under a different research
effort.
5.2. Surface Decontamination Efficacy
Test-specific results of residual surface contamination present on stainless steel before and after
decontamination with single- and multistep DCPs, as well as procedure-and-chemical-specific percent
decontamination efficacy (%DE; calculated per Section 4.6.2) results are given in Table 5-2 through 5-5.
Figures 5-6 and 5-7 summarize overall %DE (±SD) for all DCPs used for cleanup and neutralization of both
target chemicals on the reference material.
39
-------
Table 5-2. Single- and -multistep bleach decontamination test results for malathion on stainless steel
Malathion with Bleach



Decontaminated
Coupons

Positive
Control;

Procedural
Decontamination
Cleaning media
Method
ID
Mean
±SD
%RSD
Mean
SD
%RSD
Blank
Efficacy



mg/m2
mg/m2
mg/m2
%
SD
Pressurized sprayer
Single-step
MA-BL-DCP1-PS-S
<0.54
NA
NA



<0.54
>99.7
NA
Pressurized sprayer
Multistep
MA-BL-DCP1-PS-M
<0.54
NA
NA
192
24
13%
>99.7
NA
Spray bottle
Single-step
MA-BL-DCP2-SB-S
<0.54
NA
NA
<0.54
>99.7
NA
Spray bottle
Multistep
MA-BL-DCP2-SB-M
<0.54
NA
NA



>99.7
NA
Cleaning cloth
Single-step
MA-BL-DCP3-RG-S
<0.54
NA
NA



<0.54
>99.7
NA
Cleaning cloth
Multistep
MA-BL-DCP3-RG-M
<0.54
NA
NA



>99.7
NA
Cleaning sponge
Single-step
MA-BL-DCP4-SP-S
<0.54
NA
NA
160
11
7%
<0.54
>99.7
NA
Cleaning sponge
Multistep
MA-BL-DCP4-SP-M
<0.54
NA
NA
>99.7
NA
Paint roller
Single-step
MA-BL-DCP5-PR-S
<0.54
NA
NA



<0.54
>99.7
NA
Paint roller
Multistep
MA-BL-DCP5-PR-M
<0.54
NA
NA



>99.7
NA
MA-malathion; BL-bleach; DCP1 to 5-Decontamination Cleanup Procedure 1 to 5; PS-pressurized sprayer; SB-spray bottle; RG-cotton cloth; SP- sponge; PR-paint roller; S-single-step procedure; M-
multistep procedure; < or > values - calculated based on LOQ
40
-------
Table 5-3. Single- and -multistep EasyDECON® DF200 decontamination test results for malathion on stainless steel
Malathion with EasyDECON® DF200



Decontaminated Coupons
Positive Controls
Procedural Blank
Decontamination
Cleaning Media
Method
ID
Mean
±SD
%RSD
Mean
SD
%RSD
Efficacy



mg/m2
mg/r
n2
mg/m2
%
SD
Pressurized sprayer
Single-step
MA-ED-DCP1-PS-S
<0.54
NA
NA



<0.54
>99.7
NA
Pressurized sprayer
Multistep
MA-ED-DCP1-PS-M
<0.54
NA
NA
156
14
9.1%
>99.7
NA
Spray bottle
Single-step
MA-ED-DCP2-SB-S
<0.54
NA
NA
<0.54
>99.7
NA
Spray bottle
Multistep
MA-ED-DCP2-SB-M
<0.54
NA
NA



>99.7
NA
Cleaning cloth
Single-step
MA-ED-DCP3-RG-S
<0.54
NA
NA



<0.54
>99.7
NA
Cleaning cloth
Multistep
MA-ED-DCP3-RG-M
<0.54
NA
NA



>99.7
NA
Cleaning sponge
Single-step
MA-ED-DCP4-SP-S
<0.54
NA
NA
142
42
29%
<0.54
>99.7
NA
Cleaning sponge
Multistep
MA-ED-DCP4-SP-M
<0.54
NA
NA
>99.7
NA
Paint roller
Single-step
MA-ED-DCP5-PR-S
<0.54
NA
NA



<0.54
>99.7
NA
Paint roller
Multistep
MA-ED-DCP5-PR-M
<0.54
NA
NA



>99.7
NA
MA-malathion; ED-EasyDECON® DF200; DCP1 to 5-Decontamination Cleanup Procedure 1 to 5; PS-pressurized sprayer; SB-spray bottle; RG-cotton cloth; SP- sponge; PR-paint roller; S-single-
step procedure; M-multistep procedure;  values - calculated based on LOQ
41
-------
Table 5-4. Single- and -multistep bleach decontamination test results for carbaryl on stainless steel
Carbaryl with Bleach



Decontaminated Coupons
Positive Controls
Procedural Blank
Decontamination
Cleaning media
Method
ID
Mean
±SD
%RSD
Mean
SD
%RSD
Efficacy



mg/m2
mg/r
n2
mg/m2
%
SD
Pressurized sprayer
Single-step
CA-BL-DCP1-PS-S
59
12
21%



<5.4
63%
19%
Pressurized sprayer
Multistep
CA-BL-DCP1-PS-M
43
8.8
20%
178
49
27%
76%
21%
Spray bottle
Single-step
CA-BL-DCP2-SB-S
66
6.2
9.4%
<5.4
63%
18%
Spray bottle
Multistep
CA-BL-DCP2-SB-M
30
12
39%



83%
24%
Cleaning cloth
Single-step
CA-BL-DCP3-RG-S
52
11
21%



<5.4
73%
6.3%
Cleaning cloth
Multistep
CA-BL-DCP3-RG-M
33
26
81%



83%
14%
Cleaning sponge
Single-step
CA-BL-DCP4-SP-S
44
27
61%
194
7.3
3.8%
<5.4
77%
14%
Cleaning sponge
Multistep
CA-BL-DCP4-SP-M
9.1
3.8
41%
95%
4.1%
Paint roller
Single-step
CA-BL-DCP5-PR-S
47
9.1
19%



<5.4
76%
5.5%
Paint roller
Multistep
CA-BL-DCP5-PR-M
34
11
32%



82%
6.4%
CA-carbaryl; BL-bleach; DCP1 to 5-Decontamination Cleanup Procedure 1 to 5; PS-pressurized sprayer; SB-spray bottle; RG-cotton cloth; SP- sponge; PR-paint roller; S-single-step procedure; M-
multistep procedure; < or > values - calculated based on LOQ
42
-------
Table 5-5. Single- and -multistep EasyDECON® DF200 decontamination test results for carbaryl on stainless steel
Carbaryl with EasyDECON® DF200



Decontaminated Coupons
Positive Controls
Procedural Blank
Decontamination
Cleaning Media
Method
ID
Mean
±SD
%RSD
Mean
SD
%RSD





mg/m2
mg/m2
mg/m2
%
SD
Pressurized sprayer
Single-step
CA-ED-DCP1-PS-S
5.9
0.54
9.1%



<5.4
96.9%
14%
Pressurized sprayer
Multistep
CA-ED-DCP1-PS-M
<5.4
NA
NA
193
28
14.6%
>97.2%
NA
Spray bottle
Single-step
CA-ED-DCP2-SB-S
<5.4
NA
NA
<5.4
>97.2%
NA
Spray bottle
Multistep
CA-ED-DCP2-SB-M
<5.4
NA
NA



>97.2%
NA
Cleaning cloth
Single-step
CA-ED-DCP3-RG-S
<5.4
NA
NA



<5.4
>97.4%
NA
Cleaning cloth
Multistep
CA-ED-DCP3-RG-M
<5.4
NA
NA



>97.4%
NA
Cleaning sponge
Single-step
CA-ED-DCP4-SP-S
<5.4
NA
NA
210
19
9.2%
<5.4
>97.4%
NA
Cleaning sponge
Multistep
CA-ED-DCP4-SP-M
<5.4
NA
NA
>97.4%
NA
Paint roller
Single-step
CA-ED-DCP5-PR-S
10.9
7.4
68%



<5.4
94.8%
9.4%
Paint roller
Multistep
CA-ED-DCP5-PR-M
<5.4
NA
NA



>97.4%
NA
CA-carbaryl; ED-EasyDECON® DF200; DCP 1 to 5-Decontamination Cleanup Procedure 1 to 5; PS-pressurized sprayer; SB-spray bottle; RG-cotton cloth; SP- sponge; PR-paint roller; S-single-
step procedure; M-multistep procedure;  values - calculated based on LOQ
43
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Malathion decontamination with bleach and EasyDECON® DF200:
decontamination efficacy (%+SD) for single- vs. multistep DCPs
>99.7%	>99.7%	>99.7%	>99.7%	>99.7%
100%
80%
60%
LU
Q
40%
20%
0%
Legend: BL-bleach; ED-EasyDECON® DF200; DCP 1 to 5-Decontamination Cleanup Procedure 1 to 5;
Dashed columns-single-step procedure; Solid columns-multistep procedure; > - calculated based on LOQ
Figure 5-5. Malathion decontamination efficacy (%±SD) for single-vs multistep DCPs
DCP1
DCP2
DCP3
DCP4
DCP5
Carbaryl decontamination with bleach and EasyDECON® DF200:
decontamination efficacy (%+SD) for single-vs. multistep DCPs
120%
97%
83%
95%
100%
DCP1	DCP2	DCP3	DCP4	DCP5
Legend: BL-bleach; ED-EasyDECON® DF200; DCP 1 to 5-Decontamination Cleanup Procedure 1 to 5;
Dashed columns-single-step procedure; Solid columns-multistep procedure; > - calculated based on LOQ
Figure 5-6. Carbaryl decontamination efficacy (%+SD) for single-vs multistep DCPs
44
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Decontamination test results indicate that chemical surface films of malathion were prone to
chemical neutralization with DE > 99.7% for both decontaminants and all types of DCPs deployed. This
observation is in line with literature data on oxidation efficacy of OP pesticides, suggesting that OP
pesticides undergo relatively rapid chemical oxidation and/or hydrolysis in the presence of various forms of
aqueous chlorine (hypochlorous acid, HOCI; hypochlorite ion, OCI") and hydrogen peroxide (H202) [18,19], It
should be emphasized that malathion, like many of the commercially available OP pesticides, is a lipophilic
phosphorothionate (with one thione moiety (P=S) and three -OR groups attached to a phosphorus atom); its
respective oxidized analogs are more polar, characterized by a phosphorus oxygen double bond (P=0),
which actually makes the compounds more potent acetylcholinesterase (AChE) inhibitors [18], These toxic
oxidation by-products of OPs, or so-called oxon transformation products, were not analyzed in this study,
but based on the literature data, formation of oxo-organophosphates (e.g., diazoxon, maloxon) from
organothiophosphates (e.g., malathion) is higher for hypochlorite (NaOCI)- than for hydrogen peroxide
(H202)-induced reactions [19], In addition to the theoretically higher potential for formation of oxons, bleach-
based procedures deployed in this study have shown consistent - and very severe - material
incompatibilities with stainless steel, causing irreversible damage to the treated surfaces. No material
incompatibilities were observed for EasyDECON® DF200. The residue observed after drying out of
EasyDECON® DF200 was most likely caused by the cationic surfactant (benzalkonium chloride) used in
this formulation, and was easily removed by rinsing with water. Figure 5-7 shows the stainless steel material
within an hour after the completion of the multistep decontamination treatment with bleach and
EasyDECON® DF200 and rinse.


Figure 5-7. Appearance of the material surface after multistep treatment with bleach (A) and EasyDecon®
DF200 (B).
Carbaryl had an average %DE ranging from 63% to > 97.4%, depending on type of DCP and
decontaminant applied. The overall higher decontamination rates were observed for EasyDECON® DF200
(94.8% to >97.4%), compared to average 63% to 95% DE offered by (concentrated germicidal) bleach. This
is in line with literature data on carbamates, and aromatic carbamates, like carbaryl, are not especially prone
to oxidation by various chlorine-based oxidants at neutral and alkaline pH, especially at a low concentration
of decontaminant [17], Activated hydrogen peroxide formulas, however, are efficacious for oxidation of
carbamates. Hydrogen peroxide in EasyDECON® DF200 is activated by addition of so-called booster -
diacetin (glycerol diacetate). The O-bonded acetyl group of the activator reacts with strongly nucleophilic
hydroperoxy anions (OOH~) to yield peroxygenated species; the peroxygenated species (0=0) is a more
efficient oxidizer than hydrogen peroxide alone [20], The EasyDECON® DF200 decontaminant has an
additional advantage in terms of neutralization of carbaryl that is relatively insoluble in water - the addition of
so-called solubilizing agent: a quaternary ammonium compound (n-alkyl-C12.i6-N,N-dimethyl-N-benzyl
ammonium chloride) [20], This cationic surfactant "wets-out" (water-insoluble) contamination by suspending
45
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it in a micelle and enhances solubility and availability of carbaryl chemical film to the oxidizing action of
activated hydrogen peroxide [19], It is important to re-emphasize that carbaryl does undergo fast hydrolysis
in aqueous alkaline solutions [10], Both decontaminants in this study have an alkaline pH (Table 3-7) that
should theoretically aid decontamination, especially for multistep procedures with no mechanical removal
step (DCP1 and DCP2). Carbaryl decontamination tests showed the same type of bleach-stainless steel
material incompatibilities as described above for malathion and were characterized by severe corrosion of
the polished surface of the stainless steel material (as shown in the example of Figure 5-3).
The experimental results demonstrated that, in the case of chemicals that are not very soluble in
aqueous solutions, the multistep procedures offered better cleanup efficacy. The re-application step appears
be particularly important for DCPs that did not include the mechanical removal step, i.e., for spray-on DCP1
and DCP2. The re-application of decontaminant resulted in a statistically significant increase in carbaryl
decontamination efficacy for non-pressurized spray applications (i.e., for multi- versus single-step DCP2,
p<0.01). For methods with a mechanical removal step (DCP3, DCP4 and DCP5), the contribution of a
mechanical removal step to overall decontamination was studied for each type of cleaning medium and
indicated that mechanical cleaning is less vital to overall decontamination effectiveness than chemical
neutralization; results are discussed in Section 5.4.
5.3. Residual Pesticides and Cleanup Thresholds
The measured DEs for the evaluated DCPs provide information on the reduction in chemical
loading on a surface under controlled laboratory conditions. These DEs provide decision makers with
information whether these approaches should be considered in a site specific incident. The other main
consideration of any DCP is to decrease the chemical burden to levels that are considered safe for re-entry
without specialized protective equipment and ultimately for re-occupation of a building. A direct comparison
of residual surface concentrations in the laboratory experiment could be made against an actionable level.
However, it does not have a real relevance to a field response clearance goal which would be site and
situation specific. Here, the residual surface concentration levels were compared to surface cleanup goals
solely as to identify whether a DCP would have been considered successful in reaching a clearance
threshold value. It should not be construed that these DCPs will achieve such cleanup level as derived for
an actual contamination situation. These cleanup level recommendations are not legally binding on any U.S.
EPA program and should be interpreted as suggestions that program offices or individual exposure
assessors can consider and modify as needed. Currently, there are no EPA regulatory values for surface
cleanup goals. According to the National Contingency Plan (NCP) [21], risk-based cleanup goals are
determined on a site- and situation-specific basis. In this study, human health-based screening levels were
used for calculation of risk-based cleanup thresholds. The method referenced here for the derivation of risk-
based cleanup goals is based upon the information presented in the World Trade Center Indoor
Environment Assessment: Selecting Contaminants of Potential Concern and Setting Health-Based
Benchmarks [3],
The noncancer risk-based cleanup thresholds were calculated based on various toxicological data,
including hazard reference doses for oral and dermal exposures for a child (body weight 15 kilos) and adults
(body weight 80 kilos), at assumed 365-day residential exposure scenarios [4] and a conservative target
hazard quotient (THQ) of 0.1 [4], Further details on the risk-based surface cleanup threshold calculations
are provided in Appendix A. The calculated surface cleanup thresholds (for semi-porous and nonporous
materials) are given in Table A-9 in Appendix A.
46
-------
Figures 5-8 and 5-9 show post-cleanup surface concentrations of malathion and carbaryl against
calculated human health risk-based cleanup thresholds. For malathion, both decontaminants showed
reduction of malathion on the surface below the calculated cleanup threshold for adults, independent of the
DCP used (Figure 5-8). The calculated cleanup threshold for a child was lower than the quantification limit in
this study and could therefore not be met. As mentioned before, the chemical analysis of the wipes did not
assess whether either decontamination process led to the formation of the toxic byproduct malaoxon which
was beyond the scope of this study. A separate cleanup threshold calculation would be required to assess
the impact of a detectable amount of such toxic decontamination byproduct.
^ 2.50
O)
E
Post cleanup surface concentrations of malathion
vs human health based cleanup thresholds
~ Single Step DCP HMuIti step DCP
noncartcer, nonporous, adult, THQ-O.l
¦ : ~ i
n on cancer, nonporous', child, THQ=0.1
DCP1 DCP2 DCP3 DCP4 DCP5 Dcp1 DCP2 DCP3 DCP4 DCP5
Concentrated germicidal bleach	EasyDECON® DF200
Figure 5-8. Post cleanup surface concentrations of malathion versus calculated human health risk-based
cleanup thresholds - THQ: target hazard quotient[4]
In the case of carbaryl, only the EasyDECON® DF200 formulation offered cleanup efficacy allowing
reduction of the surface chemical burden below the health risk-based threshold for adults (Figure 5-9); only
13% of the test samples treated with the various EasyDECON® DF200-based DCPs showed detectable
levels (>5.4 mg/m2) of carbaryl, with one out of thirty total test samples reporting approximately two times
higher than the noncancer child human health risk-based cleanup threshold for nonporous surfaces (Table
A-9). Here again, the calculated carbaryl cleanup threshold for a child was lower than the quantification limit
in this study and could therefore not be met. The only bleach-based DCP that reduced carbaryl levels close
the human-health (adult) risk-based cleanup threshold for nonporous surfaces was the multistep DCP4.
This procedure used a large industrial grade cleaning sponge that allowed the highest surface loading of
contaminant among tested procedures, on average, approximately 25 mL of bleach per coupon test area of
approximately 929 cm2, or the equivalent of almost 270 mL of bleach per m2. Other bleach-based DCPs,
with average computed DEs ranging from 63% to 83%, reduced the carbaryl surface levels to average
47
-------
concentrations of 30 to 66 mg/m2, which are well above the calculated noncancer adult human health risk-
based cleanup threshold for nonporous surfaces (8.5 mg/m2). Consequently, additional decontamination
approaches would be required if bleach was selected to cleanup this nonporous material.
Post cleanup surface concentrations of carbaryl
vs human health based cleanup thresholds
80
70
60/
/5 0
E j
|> 40
30
20
10
0
DCP1 DCP2 DCP3 DCP4 DCP5 DCP1 DCP2 DCP3 DCP4 DCP5
Concentrated germicidal bleach	EasyDECON® DF200
Figure 5-9. Post cleanup surface concentrations of carbaryl versus calculated human health risk-based
cleanup thresholds - THQ: target hazard quotient[4]
5.4. Transfer of Pesticide to Cleaning Media and Liquid Waste
While considering the overall inter-method decontamination effectiveness for field applications, it is
important to answer questions on how mechanical cleaning contributes to the removal of the target chemical
from a contaminated surface. In addition to a better understanding of the neutralization versus mechanical
removal paradigms, the analysis of the chemical residue in expended materials provides insight on the
necessity of additional remediation strategies of solid waste prior to disposal. Mechanical removal steps of a
contaminant certainly offer an advantage in terms of achieving optimal decontamination efficacy, but
mechanical removal of contaminant also leads to generation of large amounts of contaminated solid waste.
Figure 5-10 shows the amount of expended cleaning material generated during decontamination of an
approximate area of 12 ft2, used in decontamination experiments under this project (four samples per each
type (3) of cleaning medium; 3 TCs and 1 PB per test plus cleaning media used for water rinses).
: i
non-scancer, non-porous, adult
non-cancet^tjon-porous, child, THQ=0.%*¦
%•
~Single step DCP ¦ Multi step DCP
n i
48
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V
Figure 5-10. Expended cleaning materials generated during decontamination of an approximate area of 12 ft2
using three types of cleaning media
It is also important to consider a possible transport of chemicals to liquid waste, mostly in the
context of the immobilization of a chemical/pesticide to a more labile, potentially hazardous, contamination
form, and the consequent need for development of proper procedures for handling and disposal of post-
decontamination liquid waste. The initial estimates on chemical transfer to solid and liquid waste were
performed using testing procedures described in Sections 3.5.3 and 3.5.4. The chemical-specific results of
cleaned surface area are given in Appendix A (Table A-10 and A-11) and depicted in Figures 5-11 and 5-12.
These tests were conducted without proper PCs as the purpose was to measure the relative distribution of
pesticides across surface, media, and liquid effluent, not the absolute concentration in comparison to
amount applied. The PC values for malathion and carbaryl in Figures 5-11 and 5-12, respectively, are the
best estimates of the amount of pesticide applied to the coupon (derived from values in Table
The post-cleaning concentrations (with a single-step DCP deployed using water only) show that no
significant removal of malathion or carbaryl was provided by the mechanical removal step only; the average
concentration of the pesticide present on test surfaces post-cleaning was from 29 to 37 and from 83 to 190
mg/rrr for malathion and carbaryl, respectively. This concentration is in the pre-decontamination surface
concentration range (Table 3-4). The highest relative transfer to cleaning media was observed forsimulated-
DCP4 deployed with a sponge, followed by a cloth. No malathion or carbaryl was detected on paint rollers.
No carbaryl was detected in the liquid waste from paint roller-based DCP5.
49
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8.0
7.0
6.0
q. 5.0
£
TO
w 4.0
m 3.0
£
2.0
1.0
0.0
Malathion: postcleanupsurfaceand liquid & solid waste amounts - all
mechanical cleaning media (water only)
Sponge
Cloth
Paint roller
PC (surface wipe)
~ Solid waste ¦ Liquid waste ¦ Surface concentration (post-cleaning)
Figure 5-11. Malathion post-cleanup surface, liquid and solid waste amounts for all mechanical cleaning
media; % contribution calculated based on 1A LOQ
24.0
22.0
20.0
18.0
16.0
14.0
12.0
10.0
8.0
6.0
4.0
2.0
0.0
Carbaryl: postcleanupsurfaceand liquid & solid waste amounts-all
mechanical cleaning media (water only)
Sponge
Cloth

Paint roller
PC (surface wipe)
¦ Solid waste ¦ Liquid waste ¦ Surface concentration (post-cleaning)
Figure 5-12. Carbaryl post-cleanup surface, liquid and solid waste amounts for all mechanical cleaning
media; dashed bars - no quantification, % contribution calculated based on % LOQ
These results suggest that effectiveness of the tested DCPs with decontaminants (Section 5.3)
should be attributed mostly to chemical reactivity of the decontaminants, but some cleaning media,
especially those characterized by high-liquid decontaminant loading, can take up contaminant via
mechanical wet-scrubbing and/or wiping steps. The transfer of the contaminant to liquid waste was minimal
for DCPs with mechanical removal steps, with a maximum 10% of the total amount of chemical recovered
transferred to runoff.
50
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6.0.	Quality Assurance/Quality Control
6.1.	Test Equipment Calibration
All equipment was verified as calibrated at the time of use. Calibration of instruments was done at
the frequency shown in Table 6-1. In case of any deficiencies, instruments were adjusted to meet calibration
tolerances and/or recalibrated prior to testing. In the case of the GC/MS instrument, any initial calibration
deficiencies were noted. The GC/MS was recalibrated prior to analysis. If the calibration tolerances for
continuous calibration were not met, the GC/MS was recalibrated and affected samples were re-analyzed.
Table 6-1. Instrument Calibration Frequency
Equipment
Calibration/Certification
Expected Tolerance
Results
Thermometer
Compare to independent NIST thermometer (a thermometer that is
recertified annually by either NIST or an ISO-17025 facility) value once per
quarter.
±1 °C
100%
Stopwatch
Compare to official U.S. time @ time.gov every 30 days.
± 1 min/30 days
100%
Micropipettes
Certified as calibrated at time of use. Recalibrated by gravimetric evaluation
of performance to manufacturer's specifications every year.
±5%
100%
Scale
Certified as calibrated at time of use. Calibration verified yearly by the AEMD
Metrology Laboratory.
± 1 g
100%
pH meter
Three-point calibration using NIST-traceable buffer solutions immediately
prior to testing.
± 0.1 pH units
100%
Graduated cylinder
Certified by manufacturer at the time of use.
± 1 mL
100%
Solvent dispenser
Certified by manufacturer at the time of use. Re-checked volume delivered
using graduated cylinder prior to use.
± 1 mL
100%
GC/MS
6- to 7- point calibration prior to analysis; continuous calibration prior to each
analytical run; re-calibrate when continuous calibration fails acceptance
criteria and/or after system maintenance; details in Section 4.5.
± 20% at mid-point
Carbaryl: 100%>*
Malathion: 100%b
NIST = National Institute of Standards and Technology; ISO = International Organization for Standardization;a malathion decontamination
experiments; continuous calibration results: 76-123% at mid-point; average RPD: ±18%;b carbaryl decontamination experiments; continuous
calibration results: 80-112% at mid-point; average RPD: ±9.2%
6.2. Data Quality Results for Critical Measurements
The following measurements have been deemed critical to accomplishing part or all of the project
objectives:
Initial and post-cleaning surface concentration of malathion and carbaryl in the wipe sampling
extracts as determined by GC/MS.
Contact time and dwell time.
Hydrogen peroxide concentration and pH of EasyDECON® DF200 decontamination solution prior
to each test.
Volume of decontaminant (cleaning solution) and rinse water applied.
Mass of liquid waste (runoff and rinsate).
Mass of solid waste (DCP 3 through DCP 5 only).
Volume of extraction solvent.
51
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The data quality indicators (DQIs) for test measurements are provided in Table 6-2. The limited
number of results/tests that were not within acceptance criteria (as determined in the project specific QAPP)
were not indicative of any systematic error introduced into the experimental results and do not change the
general findings of this study.
Table 6-2. Acceptance Criteria for Critical Measurements and Corresponding Test Results
Critical Measurement
Target Value and Acceptance
Criteria
Results
Contact/weathering time
30 min ± 1 min
All contact times (CTs) within 30 min ± 1 min from spiking;
test-specific results are in Appendix A, Tables A-1 through A-
8
Dwell time (decontamination
interaction time) or rinse drying time
30 min-46 h ± 5 min
All dwell times (DTs) within acceptance criteria; test-specific
results are in Appendix A, Tables A-1 through A-8
Delivery of target surface
concentration of chemical*
80-120% of target
The mean spike controls for decontamination tests were 115
± 20% SD for malathion and 69% ± 16% SD for carbaryl
with coefficients of variation <30% between tests (both
chemicals); results are in Table 4-6.
Recovery of chemical from positive
control
60-140% of theoretical target, 30%
coefficient of variation for identical
test set
All tests had <30% coefficient of variation for non-
decontaminated samples resulting from identical test set**;
test-specific results for positive control coupons are in Table
3-4.
Recovery of chemical from
decontaminated TCs
<30% coefficient of variation for
identical test set
6 out of 40 tests had >30% coefficient of variation for
decontaminated samples resulting from identical test set;
test-specific results are in Table 5-1 through 5-4
Procedural blank
< 5% of the analyte amount
recovered from the positive
control.
All procedural blank samples within acceptance criteria; all
reported 
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7.0. Summary
After comparing the decontamination efficiencies of the single- and multistep decontamination and
cleanup procedures deployed onto reference nonporous material (stainless steel), the data indicate the
following:
(a)	The specialized decontamination formula tested (activated hydrogen peroxide-based,
EasyDECON® DF200) had high decontamination effectiveness against the selected pesticides tested in this
study: >99.7% DE for malathion and 94.8% to > 97.2% DE for carbaryl. Post-decontamination residual
levels of both contaminants were lower than a human-health risk-based cleanup threshold for adults as
developed for this study. Human-health risk-based cleanup threshold for a child may not have been
reached due to the quantification limits for both contaminants in this study.
(b)	The off-the-shelf decontaminant (concentrated germicidal bleach) had > 99.7% DE for
malathion, and 63% to 83% DE for carbaryl. Only one DCP (multistep DCP 4 applied by sponge) rendered a
residual surface concentration for carbaryl near the project-specific human-health risk-based cleanup
threshold for adults. Human-health risk-based cleanup threshold for a child for carbaryl were not reached
while for malathion this threshold may not have been reached due to the higher quantification limit for
malathion in this study.
(c)	The higher solubility in water was linked to generally higher decontamination efficacy observed
for malathion. For less water-soluble carbaryl, the addition of surfactant (benzalkonium chloride) in
EasyDECON® DF200 formula was considered to influence the performance of EasyDECON® DF200-
based DCPs positively.
(d)	The natural attenuation of pesticides was confirmed to occur on nonporous materials after 24-
hours post-contamination, with significant (>90%) and rapid (within 30-minutes post-contamination)
permeation transfer observed on semi-porous material surfaces for both chemicals. These results indicated
that further studies are needed for optimization of decontamination procedures for neutralization of chemical
agents absorbed into semi-porous building materials, including potential modification of the decontamination
solution.
(e)	The solid and liquid waste generated when using only water was confirmed to be contaminated
with the applied pesticides, with generation rates of chemical mass per cleaned area reaching tens of
milligrams per m2; the rate of chemical transfer to waste seemed to be mostly related to type of cleaning
media used and to a lesser extent, chemical solubility in water. The long-term chemical reactivity of
decontaminants in liquid and solid and treatment methods for neutralization of contaminated waste were,
however, not addressed in the present study.
The results of this study confirm that decontamination and cleanup methods should be selected
based on the reactivity of the chemical agent-active ingredient/ingredients of the decontaminant chemical,
as well as the ability of the decontaminant to physically remove the chemical agent on the surface of the
material. Such targeted DCPs should ideally consider the physical and chemical properties (e.g., water
solubility) of the chemical agent as well as the potential of the chemical to migrate/permeate into semi-
porous or porous materials. The multiple cleanup decontamination modes tested in this study were good
candidate DCPs for neutralization of high pesticide burdens from nonporous surfaces. Further studies on
optimization of decontamination strategies of porous or semi-porous surfaces are currently underway.
53
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This project was a bench scale level study with the limitations that this effort did not address the
possible formation of toxic decontamination byproducts. This omission is noteworthy considering the use of
malathion as one of the targeted pesticides that may degrade to malaoxon, an oxidation byproduct of equal
or higher toxicity than malathion. Further, all materials were clean and prepared specifically for this study;
dirt and grime may impact the efficacy. Lastly, pesticides were applied here as a neat film. This application
may deviate from the application of a technical formulation containing these pesticides.
54
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permeable layer of paint or sealant into porous subsurfaces. EPA/600/R-16/173. Office of Research and
Development. National Homeland Security Research Center. Decontamination and Consequence
Management Division. October 2016.
[15]	PubChem (2017) PubChem Compound Database https://pubchem.ncbi.nlm.nih.gov/ (last
accessed September 27, 2017)
[16]	IPCS (1994) International Programme on Chemical Safety. Environmental Health Criteria 153.
Carbaryl. http://www.inchem.org/documents/ehc/ehc/ehc153.htm (last accessed September 11, 2017).
[17]	Mulligan, C.N.; Yong, R.N. (2004) Natural attenuation of contaminated soils. Environ. Int. 30,
587-601.
[18]	Duirk, S.E.; Desetto, L.M.; Davis, G.M. (2009) Transformation of organophosphorus pesticides
in the presence of aqueous chlorine: Kinetics, pathways, and structure-activity relationships. Environ. Sci.
Technol. 43, 2335-2340.
[19]	Kralj, M.B; Trebse, P; Franko, M (2006) Oxidation as a pre-step in determination of
organophosphorus compounds by the AChE-TLS bioassay. Acta Chim. Slov. 53, 43-51
[20]	Intelagard (2017) EasyDECON® DF200. Technology and Performance Data.
https://intelagand.com/wp-content/uploads/2017/05/DF20Q-Summarv-SL.pdf (last accessed September 11,
2017).
[21]	National Contingency Plan https://www.epa.gov/emergencv-response/national-oil-and-
hazardous-substances-pollution-contingencv-plan-ncp-overview (last accessed September 27, 2017)
56
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Appendix A: Supporting Information
57
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Table A-1. Experimental parameters formalathion decontamination with bleach (single-step procedure)

Contamination
Decontamination Step
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Single-step DCP1 Hand-held pressurized sprayer
DCP1S-MA-SS-BL-PS-1-TC-1-190117
10:10:00
10:10:00
10:10:10
20.0
31
11:10:00
11:10:10
20.0
17
11:10:00
11:12:49
DCP1S-MA-SS-BL-PS-1-TC-2-190117
10:20:00
10:20:00
10:20:11
20.0
30
11:20:00
11:20:11
20.0
16
11:20:00
11:22:44
DCP1S-MA-SS-BL-PS-1-TC-3-190117
10:30:00
10:30:00
10:30:10
20.0
27
11:30:00
11:30:10
20.0
17
11:30:00
11:32:52
Single-step DCP 2 Spray bottle
DCP2S-MA-SS-BL-SB-1-TC-1-190117
10:40:00
10:40:00
10:40:10
19.6
19
11:40:00
11:40:10
20.6
18
11:40:00
11:42:48
DCP2S-MA-SS-BL-SB-1-TC-2-190117
10:50:00
10:50:00
10:50:10
20.0
19
11:50:00
11:50:11
19.7
17
11:50:00
11:52:47
DCP2S-MA-SS-BL-SB-1-TC-3-190117
11:00:00
11:00:00
11:00:11
20.0
18
12:00:00
12:00:10
20.2
16
12:00:00
12:03:01
Single-step DCP 3 Cleaning cloth
DCP3S-MA-SS-BL-RG-1-TC-1-120117
10:24:00
10:24:00
10:24:10
4.5
4.0
11:24:00
11:24:10
2.7
2
11:24:00
11:27:01
DCP3S-MA-SS-BL-RG-1-TC-2-120117
10:31:00
10:31:00
10:31:10
4.4
3.0
11:31:00
11:31:10
3.1
2
11:31:00
11:34:05
DCP3S-MA-SS-BL-RG-1-TC-3-120117
10:38:00
10:38:00
10:38:10
3.5
4.0
11:38:00
11:38:10
3.2
2
11:38:00
11:41:08
Single-step DCP 4 Cleaning sponge
DCP4S-MA-SS-BL-SP-1-TC-1-120117
10:45:00
10:45:00
10:45:10
35.7
35
11:45:00
11:45:10
16.2
15
11:45:00
11:48:20
DCP4S-MA-SS-BL-SP-1-TC-2-120117
10:52:00
10:52:00
10:52:10
32.9
31
11:52:00
11:52:10
14.7
13
11:52:00
11:55:06
DCP4S-MA-SS-BL-SP-1-TC-3-120117
10:59:00
10:59:00
10:59:10
34.8
33
11:59:00
11:59:10
7.5
5
11:59:00
12:02:18
Single-step DCP 5 Paint roller
D C P5S-MA-S S-BL- P R-1 -TC-1 -120117
11:06:00
11:06:00
11:06:10
2.8
3.0
12:06:00
12:06:10
5.1
4
12:06:00
12:08:57
D C P5S-MA-S S-BL-PR-1-TC-2-120117
11:13:00
11:13:00
11:13:10
3.7
4.0
12:13:00
12:13:10
4.2
4
12:13:00
12:16:11
D C P5S-MA-S S-BL- P R-1 -TC-3-120117
11:20:00
11:20:00
11:20:10
3.1
3.0
12:20:00
12:20:10
3.4
33
12:20:00
12:23:03
58
-------
Table A-2. Experimental parameters for malathion decontamination with bleach (multistep procedure)

Contamination
Decontamination Step 1
Decontamination Step 2
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Multistep DCP 1 Hand-held pressurized sprayer
DCP1M-M A-SS-BL-PS-4/24-T C-1 -200117
8:50:00
8:50:00
8:50:10
20
23
12:50:00
12:50:10
20
18
12:50:00
12:50:11
20
21
12:50:00
12:52:48
DCP1 M-M A-SS-BL-PS-4/24-T C-2-200117
9:00:00
9:00:00
9:00:10
20
23
13:00:00
13:00:12
20
22
13:00:00
13:00:10
20
20
13:00:00
13:02:43
DCP1 M-M A-SS-BL-PS-4/24-T C-3-200117
9:10:00
9:10:00
9:10:10
20
21
13:10:00
13:10:10
20
26
13:10:00
13:10:12
20
19
13:10:00
13:12:56
DCP2M-M A-SS-BL-PS-4/24-PB-1 -200117
....
9:20:00
9:20:10
20
24
13:20:00
13:20:15
20
29
13:20:00
13:20:10
20
21
13:20:00
13:22:39
Multistep DCP 2 Spray bottle
DCP2M-M A-SS-BL-SB-4/24-T C-1 -200117
9:30:00
9:30:00
9:30:13
23.0
21
13:30:00
13:30:13
19.7
19
13:30:00
13:30:15
20.2
19
13:30:00
13:32:54
DCP2M-MA-SS-BL-SB-4/24-TC-2-200117
9:40:00
9:40:00
9:40:12
20.9
19
13:40:00
13:40:12
19.8
19
13:40:00
13:40:15
19.6
18
13:40:00
13:42:56
DCP2M-MA-SS-BL-SB-4/24-TC-3-200117
9:50:00
9:50:00
9:50:12
21.9
20
13:50:00
13:50:12
20.0
18
13:50:00
13:50:16
20.4
19
13:50:00
13:52:51
DCP2M-M A-SS-BL-SB-4/24-PB-1 -200117
....
10:00:00
10:00:12
22.1
22
14:00:00
14:00:10
20.3
20
14:00:00
14:00:13
19.7
19
14:00:00
14:02:55
Multistep DCP 3 Cleaning cloth
DCP3M-MA-SS-BL-RG-4/24-T C-1 -130117
9:00:00
9:00:00
9:00:10
3.5
2.0
13:00:00
13:00:10
3.9
3
13:00:00
13:00:10
3.7
2
13:00:00
13:03:45
DCP3M-MA-SS-BL-RG-4/24-T C-2-130117
9:07:00
9:07:00
9:07:10
3.8
3.0
13:07:00
13:07:10
4.5
3
13:07:00
13:07:10
3.3
2
13:07:00
13:09:55
DCP3M-MA-SS-BL-RG-4/24-T C-3-130117
9:14:00
9:14:00
9:14:10
4.4
3.0
13:14:00
13:14:10
4.3
4
13:14:00
13:14:10
2.9
3
13:14:00
13:17:03
DCP3M-MA-SS-BL-RG-4/24-PB-1 -130117
....
9:21:00
9:21:10
4.3
3.0
13:21:00
13:21:10
3.7
2
13:21:00
13:21:10
3.3
2
13:21:00
13:24:13
Multistep DCP 4 Cleaning sponge
DCP4M-M A-SS-BL-SP-4/24-T C-1 -130117
9:28:00
9:28:00
9:28:10
28.7
27
13:28:00
13:28:10
34.1
33
13:28:00
13:28:10
12.4
11
13:28:00
13:31:06
DCP4M-M A-SS-BL-SP-4/24-T C-2-130117
9:35:00
9:35:00
9:35:10
21.2
21
13:35:00
13:35:10
37.1
36
13:35:00
13:35:10
11.8
11
13:35:00
13:38:03
DCP4M-M A-SS-BL-SP-4/24-T C-3-130117
9:42:00
9:42:00
9:42:10
21.6
21
13:42:00
13:42:10
28.3
27
13:42:00
13:42:10
26.8
26
13:42:00
13:45:11
DCP4M-M A-SS-BL-SP-4/24-PB-1 -130117
....
9:49:00
9:49:10
32.5
32
13:49:00
13:49:10
24.0
23
13:49:00
13:49:10
8.3
8
13:49:00
13:52:02
Multistep DCP 5 Paint roller
DCP5M-MA-SS-BL-PR-4/24-TC-1-130117
9:56:00
9:56:00
9:56:10
4.0
4.0
13:56:00
13:56:10
2.4
2
13:56:00
13:56:10
1.2
4
13:56:00
13:59:01
DCP5M-MA-SS-BL-PR-4/24-TC-2-130117
10:03:00
10:03:00
10:03:10
8.4
3.0
14:03:00
14:03:10
6.1
6
14:03:00
14:03:10
3.5
3
14:03:00
14:06:00
DCP5M-MA-SS-BL-PR-4/24-TC-3-130117
10:10:00
10:10:00
10:10:10
2.6
0
14:10:00
14:10:10
2.8
2
14:10:00
14:10:10
3.4
3
14:10:00
14:12:58
DCP5M-MA-SS-BL-PR-4/24-PB-1 -130117
....
10:17:00
10:17:10
5.0
6.0
14:17:00
14:17:10
6.8
7
14:17:00
14:17:10
3.8
4
14:17:00
14:19:59
59
-------
Table A-3. Experimental parameters for carbaryl decontamination with bleach (single-step procedure)

Contamination
Decontamination Step
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Single-step DCP 1 Hand-held pressurized sprayer
DCP1S-CA-SS-BL-PS-1 -TC-1-080217
10:10:00
10:10:00
10:10:00
20
28
11:10:00
11:10:10
20
23
11:10:00
11:12:58
DCP1 S-CA-SS-BL-PS-1 -TC-2-080217
10:20:00
10:20:00
10:20:10
20
26
11:20:00
11:20:11
20
24
11:20:00
11:22:51
DCP1 S-CA-SS-BL-PS-1 -TC-3-080217
10:30:00
10:30:00
10:30:10
20
27
11:30:00
11:30:10
20
22
11:30:00
11:33:00
Single-step DCP 2 Spray bottle
DCP2S-CA-SS-BL-SB-1-TC-1-080217
10:40:00
10:40:00
10:40:10
20.7
21
11:40:00
11:40:22
20.5
18
11:40:00
11:42:51
DCP2S-CA-SS-BL-SB-1 -TC-2-080217
10:50:00
10:50:00
10:50:10
20.9
19
11:50:00
11:50:15
20.8
19
11:50:00
11:53:02
DCP2S-CA-SS-BL-SB-1 -TC-3-080217
11:00:00
11:00:00
11:00:10
19.9
19
12:00:00
12:00:35
19.5
18
12:00:00
12:02:58
Single-step DCP 3 Cleaning cloth
DCP3S-CA-SS-BL-RG-1-TC-1-150217
10:24:00
10:24:00
10:24:10
3.0
2.0
11:24:00
11:24:10
2
1
11:24:00
11:26:57
DCP3S-CA-SS-BL-RG-1-TC-2-150217
10:31:00
10:31:00
10:31:10
3.1
2.0
11:31:00
11:31:10
2.1
1
11:31:00
11:33:58
DCP3S-CA-SS-BL-RG-1-TC-3-150217
10:38:00
10:38:00
10:38:10
3.5
3.0
11:38:00
11:38:10
2.8
2
11:38:00
11:40:51
Single-step DCP 4 Cleaning sponge
DCP4S-CA-SS-BL-SP-1-TC-1-150217
10:45:00
10:45:00
10:45:10
16
15
11:45:00
11:45:10
16.9
15
11:45:00
11:47:48
DCP4S-CA-SS-BL-SP-1 -T C-2-150217
10:52:00
10:52:00
10:52:10
15.3
14
11:52:00
11:52:10
16.9
16
11:52:00
11:55:03
DCP4S-CA-SS-BL-SP-1 -T C-3-150217
10:59:00
10:59:00
10:59:10
19.7
19
11:59:00
11:59:10
14.7
14
11:59:00
12:02:59
Single-step DCP 5 Paint roller
DCP5S-CA-SS-BL-PR-1-TC-1-150217
11:06:00
11:06:00
11:06:10
5.1
5.0
12:06:00
12:06:10
5.1
4
12:06:00
12:08:56
DCP5S-CA-SS-BL-PR-1-TC-2-150217
11:13:00
11:13:00
11:13:10
6.7
6.0
12:13:00
12:13:10
3.4
3
12:13:00
12:15:52
DCP5S-CA-SS-BL-PR-1-TC-3-150217
11:20:00
11:20:00
11:20:10
4.0
4.0
12:20:00
12:20:10
2.8
2
12:20:00
12:22:49
60
-------
Table A-4. Experimental parameters for carbaryl decontamination with bleach (multistep procedure)

Contamination
Decontamination Step 1
Decontamination Step 2
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Multistep DCP 1 Hand-held pressurized sprayer
DCP1M-CA-SS-BL-PS-4/24-T C-1 -090217
8:50:00
8:50:00
8:50:10
20
22
12:50:00
12:50:10
20
27
12:50:00
12:50:10
20
23
12:50:00
12:52:43
DCP1M-CA-SS-BL-PS-4/24-T C-2-090217
9:00:00
9:00:00
9:00:10
20
24
13:00:00
13:00:10
20
26
13:00:00
13:00:10
20
21
13:00:00
13:03:07
DCP1M-CA-SS-BL-PS-4/24-T C-3-090217
9:10:00
9:10:00
9:10:08
20
24
13:10:00
13:10:10
20
24
13:10:00
13:10:10
20
22
13:10:00
13:12:55
DCP2M-CA-SS-BL-SB-4/24-PB-1 -090217
....
9:20:00
9:20:10
20
23
13:20:00
13:20:10
20
24
13:20:00
13:20:10
20
22
13:20:00
13:23:01
Multistep DCP 2 Spray bottle
DCP2M-CA-SS-BL-SB-4/24-T C-1 -090217
9:30:00
9:30:00
9:30:12
21.9
20
13:30:00
13:30:10
20.4
20
13:30:00
13:30:30
20.2
19
13:30:00
13:33:00
DCP2M-CA-SS-BL-SB-4/24-T C-2-090217
9:40:00
9:40:00
9:40:11
20.0
19
13:40:00
13:40:10
20.4
20
13:40:00
13:40:44
20.7
19
13:40:00
13:42:58
DCP2M-CA-SS-BL-SB-4/24-T C-3-090217
9:50:00
9:50:00
9:50:10
19.6
19
13:50:00
13:50:10
20.0
20
13:50:00
13:50:46
20.2
19
13:50:00
13:53:05
DCP2M-CA-SS-BL-SB-4/24-PB-1 -090217
....
10:00:00
10:00:11
20.3
19
14:00:00
14:00:33
20.7
20
14:00:00
14:00:40
21.0
19
14:00:00
14:03:04
Multistep DCP 3 Cleaning cloth
DCP3M-CA-SS-BL-RG-4/24-TC-1-160217
9:00:00
9:00:00
9:00:10
3.5
3.0
13:00:00
13:00:10
3.8
2
13:00:00
13:00:10
1.9
1
13:00:00
13:02:45
DCP3M-CA-SS-BL-RG-4/24-TC-2-160217
9:07:00
9:07:00
9:07:10
3.8
3.0
13:07:00
13:07:10
3.7
2
13:07:00
13:07:10
2.1
2
13:07:00
13:09:52
DCP3M-CA-SS-BL-RG-4/24-TC-3-160217
9:14:00
9:14:00
9:14:10
4.0
4.0
13:14:00
13:14:10
2.9
1
13:14:00
13:14:10
2.2
2
13:14:00
13:16:50
DCP3M-CA-SS-BL-RG-4/24-PB-1 -160217
....
9:21:00
9:21:10
3.5
3.0
13:21:00
13:21:10
2.9
2
13:21:00
13:21:10
2.7
2
13:21:00
13:24:00
Multistep DCP 4 Cleaning sponge
DCP4M-CA-SS-BL-SP-4/24-T C-1 -160217
9:28:00
9:28:00
9:28:10
40.3
40
13:28:00
13:28:10
31.1
30
13:28:00
13:28:10
27
26
13:28:00
13:31:00
DCP4M-CA-SS-BL-SP-4/24-T C-2-160217
9:35:00
9:35:00
9:35:10
28.5
27
13:35:00
13:35:10
19
17
13:35:00
13:35:10
15
13
13:35:00
13:37:45
DCP4M-CA-SS-BL-SP-4/24-T C-3-160217
9:42:00
9:42:00
9:42:10
21.9
21
13:42:00
13:42:10
29.6
28
13:42:00
13:42:10
15.3
16
13:42:00
13:44:51
DCP4M-CA-SS-BL-SP-4/24-PB-1 -160217
....
9:49:00
9:49:10
16.4
15
13:49:00
13:49:10
29.9
27
13:49:00
13:49:10
22.5
21
13:49:00
13:52:00
Multistep DCP 5 Paint roller
DCP5M-CA-SS-BL-PR-4/24-TC-1-160217
9:56:00
9:56:00
9:56:10
4.7
3.0
13:56:00
13:56:10
4.4
3
13:56:00
13:56:10
2.9
2
13:56:00
13:58:41
DCP5M-CA-SS-BL-PR-4/24-TC-2-160217
10:03:00
10:03:00
10:03:10
4.5
4.0
14:03:00
14:03:10
5.5
6
14:03:00
14:03:10
4.8
4
14:03:00
14:05:56
DCP5M-CA-SS-BL-PR-4/24-TC-3-160217
10:10:00
10:10:00
10:10:10
6.4
6.0
14:10:00
14:10:10
4.4
4
14:10:00
14:10:10
2.5
3
14:10:00
14:12:49
DCP5M-CA-SS-BL-PR-4/24-PB-1-160217
....
10:17:00
10:17:10
4.9
5.0
14:17:00
14:17:10
4.3
4
14:17:00
14:17:10
2.7
3
14:17:00
14:19:47
61
-------
Table A-5. Experimental parameters for malathion decontamination with EasyDECON® DF200 (single-step procedure)

Contamination
Decontamination Step
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Single-step DCP 1 Hand-held pressurized sprayer
DCP1S-MA-SS-ED-PS-24-TC-1-291216
10:10:00
10:10:05
10:10:15
20
48
11:10:00
11:10:10
20
23
11:10:00
11:13:06
DCP1S-M A-SS-ED-PS-24-TC-2-291216
10:20:00
10:20:00
10:20:19
20
37
11:20:00
11:20:13
20
18
11:20:00
11:23:09
DCP1 S-M A-SS-ED-PS-24-TC-3-291216
10:30:00
10:30:00
10:30:18
20
39
11:30:00
11:30:13
20
18
11:30:00
11:33:31
Single-step DCP 2 Spray bottle
DCP2S-MA-SS-ED-SB-24-TC-1-291216
10:40:00
10:40:00
10:40:15
20.7
18
11:40:30
11:40:43
21.7
19
11:40:00
11:43:32
DCP2S-M A-SS-ED-SB-24-TC-2-291216
10:50:00
10:50:00
10:50:15
19.8
17
11:50:00
11:50:19
21.5
18
11:50:00
11:53:28
DCP2S-M A-SS-ED-SB-24-TC-3-291216
11:00:00
11:00:00
11:00:22
20.4
21
12:00:00
12:00:16
21.2
18
12:00:00
12:03:21
Single-step DCP 3 Cleaning cloth
DCP3S-MA-SS-ED-RG-1-TC-1-050117
10:24:00
10:24:00
10:24:10
11.3
9.0
11:24:00
11:24:10
0.2
0
11:24:00
11:26:57
DCP3S-MA-SS-ED-RG-1-TC-2-050117
10:31:00
10:31:00
10:31:10
6.3
4.0
11:31:00
11:31:10
2.2
1
11:31:00
11:34:01
DCP3S-MA-SS-ED-RG-1-TC-3-050117
10:38:00
10:38:00
10:38:10
5.0
2.0
11:38:00
11:38:10
7.5
1
11:38:00
11:40:52
Single-step DCP 4 Cleaning sponge
DCP4S-MA-SS-ED-SP-1-TC-1-050117
10:45:00
10:45:00
10:45:10
16.8
16
11:45:00
11:45:10
9.0
6
11:45:00
11:47:47
DCP4S-MA-SS-ED-SP-1-TC-2-050117
10:52:00
10:52:00
10:52:10
21.0
20
11:52:00
11:52:10
19.1
18
11:52:00
11:55:00
DCP4S-MA-SS-ED-SP-1-TC-3-050117
10:59:00
10:59:00
10:59:10
22.6
20
11:59:00
11:59:10
14.5
12
11:59:00
12:02:01
Single-step DCP 5 Paint roller
DCP5S-MA-SS-ED-PR-1-TC-1-050117
11:06:00
11:06:00
11:06:10
4.8
4.0
12:06:00
12:06:10
6.4
6
12:06:00
12:08:51
DCP5S-MA-SS-ED-PR-1-TC-2-050118
11:13:00
11:13:00
11:13:10
4.3
4.0
12:13:00
12:13:10
7.6
7
12:13:00
12:15:47
DCP5S-MA-SS-ED-PR-1-TC-3-050119
11:20:00
11:20:00
11:20:10
5.6
4.0
12:20:00
12:20:10
8.6
8
12:20:00
12:23:02
62
-------
Table A-6. Experimental parameters for malathion decontamination with EasyDECON® DF200 (multistep procedure)

Contamination
Decontamination Step 1
Decontamination Step 2
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Multistep DCP 1 Hand-held pressurized sprayer
D C P1M-MA-SS- ED- PS-4/2 4-TC-1 -301216
9:00:00
9:00:00
9:00:10
20
46
13:00:00
13:00:12
20
55
13:00:00
13:00:11
20
20
13:00:00
13:03:24
D C P1M-MA-SS- ED-PS-4/24-TC-2-301216
9:10:00
9:10:00
9:10:14
20
49
13:10:00
13:10:14
20
55
13:10:00
13:10:14
20
19
13:10:00
13:13:32
D C P1 M-MA-SS- ED-PS-4/24-TC-3-301216
9:20:00
9:20:00
9:20:11
20
30
13:20:00
13:20:15
20
54
13:20:00
13:20:10
20
20
13:20:00
13:23:26
Multistep DCP 2 Spray bottle
D C P2M-MA-SS- ED-SB-4/24-TC-1-301216
9:30:00
9:30:00
9:30:16
20.3
18
13:30:00
13:30:17
20.2
19
13:30:00
13:30:16
20.3
18
13:30:00
13:33:16
D C P2M-MA-SS- ED-SB-4/24-T C-2-301216
9:40:00
9:40:00
9:40:16
20.1
17
13:40:00
13:40:18
20.1
19
13:40:00
13:40:13
20.5
18
13:40:00
13:43:16
D C P2M-MA-SS- ED-SB-4/24-T C-3-301216
9:50:00
9:50:00
9:50:19
21.2
20
13:50:00
13:50:14
19.5
17
13:50:00
13:50:17
20.3
18
13:50:00
13:53:11
DCP2M-MA-SS-ED-SB-4/24-PB-1-301216
....
10:00:00
10:00:18
20.5
19
14:00:00
14:00:14
19.7
18
14:00:00
14:00:16
20.9
17
14:00:00
14:03:09
Multistep DCP 3 Cleaning cloth
D C P3M-MA-S S- E D- RG-4/2 4-TC-1 -060117
9:00:00
9:00:00
9:00:10
7.0
3.0
13:00:00
13:00:10
5.3
1.0
13:00:00
13:00:10
9.4
1
13:00:00
13:03:15
D C P3M-MA-S S- E D- RG-4/2 4-TC-2-060117
9:07:00
9:07:00
9:07:10
4.7
3.0
13:07:00
13:07:10
4.8
3.0
13:07:00
13:07:10
2.2
2
13:07:00
13:10:05
D C P3M-MA-S S- E D- RG-4/2 4-TC-3-060117
9:14:00
9:14:00
9:14:10
3.8
1.0
13:14:00
13:14:10
7.6
5.0
13:14:00
13:14:10
1.6
1
13:14:00
13:17:09
D C P3M-MA-S S-ED-RG-4/24-PB-1-060117
....
9:21:00
9:21:10
4.7
2.0
13:21:00
13:21:10
5.3
2.0
13:21:00
13:21:10
2.1
1
13:21:00
13:24:17
Multistep DCP 4 Cleaning sponge
D C P4M-MA-SS- ED-S P-4/2 4-TC-1 -060117
9:28:00
9:28:00
9:28:10
34.4
32
13:28:00
13:28:10
12.9
11
13:28:00
13:28:10
11.4
10
13:28:00
13:31:24
D C P4M-MA-SS- ED-S P-4/2 4-T C-2-060117
9:35:00
9:35:00
9:35:10
20.4
18
13:35:00
13:35:10
8.9
7
13:35:00
13:35:10
7.4
6
13:35:00
13:38:18
DCP4M-MA-SS-ED-S P-4/24-TC-3-060117
9:42:00
9:42:00
9:42:10
29.8
27
13:42:00
13:42:10
19.2
18
13:42:00
13:42:10
5.0
4
13:42:00
13:45:08
DCP4M-MA-SS-ED-S P-4/24-PB-1-060117
....
9:49:00
9:49:10
27.2
29
13:49:00
13:49:10
13.0
10
13:49:00
13:49:10
6.8
5
13:49:00
13:52:18
Multistep DCP 5 Paint roller
D C P5M-MA-S S- E D- PR-4/2 4-TC-1-060117
9:56:00
9:56:00
9:56:10
2.5
2.0
13:56:00
13:56:10
7.1
7.0
13:56:00
13:56:10
2.9
2
13:56:00
13:59:08
D C P5M-MA-S S- E D- PR-4/2 4-TC-2-060117
10:03:00
10:03:00
10:03:10
3.3
3.0
14:03:00
14:03:10
9.9
10
14:03:00
14:03:10
3.8
4
14:03:00
14:06:06
D C P5M-MA-S S- E D- PR-4/2 4-TC-3-060117
10:10:00
10:10:00
10:10:10
2.8
3.0
14:10:00
14:10:10
6.1
5.0
14:10:00
14:10:10
6.5
5
14:10:00
14:13:21
D C P5M-MA-S S- E D- PR-4/2 4- PB-1-060117
....
10:17:00
10:17:10
2.2
2.0
14:17:00
14:17:10
7.2
6.0
14:17:00
14:17:10
7.3
6
14:17:00
14:20:03
63
-------
Table A-7. Experimental parameters for carbaryl decontamination with EasyDECON® DF200 (single-step procedure)

Contamination
Decontamination Step
Water Rinse
Wipe sampling
Test and
Start
Start
Stop
Amount
Waste
Start
Stop
Amount
Waste
Start
Stop
Sample ID
Time
Time
Time
Applied
collected
Time
Time
Applied
collected
Time
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Single-step DCP1 Hand-held pressurized sprayer
DCP1S-CA-SS-ED-PS-1-TC-1-250117
10:10:00
10:10:00
10:10:10
20
21
11:10:00
11:10:10
20
23
11:10:00
11:13:08
DCP1S-CA-SS-ED-PS-1-TC-2-250117
10:20:00
10:20:00
10:20:12
20
22
11:20:00
11:20:13
20
20
11:20:00
11:23:08
DCP1S-CA-SS-ED-PS-1-TC-3-250117
10:30:00
10:30:00
10:30:13
20
22
11:30:00
11:30:10
20
21
11:30:00
11:33:03
DCP2S-CA-SS-ED-SB-1-TC-1-250117
10:40:00
10:40:00
10:40:19
20.0
19
11:40:00
11:40:20
19.5
20
11:40:00
11:43:04
DCP2S-CA-SS-ED-SB-1-TC-2-250117
10:50:00
10:50:00
10:50:18
20.6
19
11:50:00
11:50:13
19.9
20
11:50:00
11:53:03
DCP2S-CA-SS-ED-SB-1-TC-3-250117
11:00:00
11:00:00
11:00:24
19.4
19
12:00:00
12:00:13
19.7
20
12:00:00
12:02:59
Single-step DCP 3 Cleaning cloth
DCP3S-CA-SS-ED-RG-1-TC-1-010217
10:24:00
10:24:00
10:24:10
8.5
7.0
11:24:00
11:24:10
1.9
1
11:24:00
11:27:02
DCP3S-CA-SS- ED-RG-1 -TC-2-010217
10:31:00
10:31:00
10:31:10
9.3
8.0
11:31:00
11:31:10
2.2
1
11:31:00
11:33:57
DCP3S-CA-SS- ED-RG-1 -TC-3-010217
10:38:00
10:38:00
10:38:10
9.0
7.0
11:38:00
11:38:10
2.5
1
11:38:00
11:40:40
Single-step DCP 4 Cleaning sponge
DCP4S-CA-SS-ED-SP-1-TC-1-010217
10:45:00
10:45:00
10:45:10
49.1
47
11:45:00
11:45:10
18.6
17
11:45:00
11:47:45
DCP4S-CA-SS-ED-SP-1-TC-2-010217
10:52:00
10:52:00
10:52:10
31.7
29
11:52:00
11:52:10
22.0
21
11:52:00
11:54:35
DCP4S-CA-SS-ED-SP-1-TC-3-010217
10:59:00
10:59:00
10:59:10
38.4
35
11:59:00
11:59:10
27.7
26
11:59:00
12:01:45
Single-step DCP 5 Paint roller
DCP5S-CA-SS-ED-PR-1-TC-1-010217
11:06:00
11:06:00
11:06:10
19.0*
19*
12:06:00
12:06:10
9.2
8
12:06:00
12:08:38
DCP5S-CA-SS-ED-PR-1-TC-2-010217
11:13:00
11:13:00
11:13:10
3.5
3.0
12:13:00
12:13:10
16.1
15
12:13:00
12:15:40
DCP5S-CA-SS-ED-PR-1-TC-3-010217
11:20:00
11:20:00
11:20:10
3.9
3.0
12:20:00
12:20:10
20.6
19
12:20:00
12:22:50
*No analytical notes on reason for the high loading; the outlier excluded from average loading calculations
64
-------
Table A-8. Experimental parameters for carbaryl decontamination with EasyDECON® DF200 (multistep procedure)

Contamination
Decontamination Step 1
Decontamination Step 2
Water Rinse
Wipe sampling
Sample ID
Start
Time
Start
Time
Stop
Time
Amount
Applied
Waste
collected
Start
Time
Stop
Time
Amount
Applied
Waste
collected
Start
Time
Stop
Time
Amount
Applied
Waste
collected
Start
Time
Stop
Time

(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
(g)
(hh:mm:ss)
Multistep DCP 1 Hand-held pressurized sprayer
DCP1M-CA-SS-ED-PS-4/24-TC-1-260117
8:50:00
8:50:00
8:50:13
20
26
12:50:00
12:50:10
20
22
12:50:00
12:50:10
20
22
12:50:00
12:53:00
DCP1M-CA-SS-ED-PS-4/24-TC-2-260117
9:00:00
9:00:00
9:00:12
20
31
13:00:00
13:00:10
20
23
13:00:00
13:00:08
20
23
13:00:00
13:02:50
DCP1M-CA-SS-ED-PS-4/24-TC-3-260117
9:10:00
9:10:00
9:10:15
20
31
13:10:00
13:10:10
20
23
13:10:00
13:10:09
20
23
13:10:00
13:12:43
DCP1M-CA-SS-ED-PS-4/24-PB-1-260117
....
9:20:00
9:20:11
20
31
13:20:00
13:20:10
20
23
13:20:00
13:20:10
20
23
13:20:00
13:22:45
Multistep DCP 2 Spray bottle
DCP2M-CA-SS-ED-SB-4/24-TC-1-260117
9:30:00
9:30:00
9:30:35
22.5
31
13:30:00
13:30:35
21.0
21
13:30:00
13:30:35
19.6
21
13:30:00
13:32:43
DCP2M-CA-SS-ED-SB-4/24-TC-2-260117
9:40:00
9:40:00
9:40:37
20.9
20
13:40:00
13:40:35
19.6
19
13:40:00
13:40:31
20.4
19
13:40:00
13:42:53
DCP2M-CA-SS-ED-SB-4/24-TC-3-260117
9:50:00
9:50:00
9:50:35
22.9
19
13:50:00
13:50:38
20.0
19
13:50:00
13:50:38
20.3
19
13:50:00
13:52:48
DCP2M-CA-SS-ED-SB-4/24-PB-1-260117
....
10:00:00
10:00:28
19.8
21
14:00:00
14:00:30
19.9
19
14:00:00
14:00:45
21.9
19
14:00:00
14:02:44
Multistep DCP 3 Cleaning cloth
DCP3M-CA-SS-ED-RG-4/24-TC-1-020217
9:00:00
9:00:00
9:00:10
8.4
6.0
13:00:00
13:00:10
8.0
6.0
13:00:00
13:00:10
3.2
3
13:00:00
13:02:45
DCP3M-CA-SS-ED-RG-4/24-TC-2-020217
9:07:00
9:07:00
9:07:10
6.6
5.0
13:07:00
13:07:10
8.1
7.0
13:07:00
13:07:10
2.0
1
13:07:00
13:09:43
DCP3M-CA-SS-ED-RG-4/24-TC-3-020217
9:14:00
9:14:00
9:14:10
8.2
6.0
13:14:00
13:14:10
8.8
6.0
13:14:00
13:14:10
2.1
1
13:14:00
13:16:48
DCP3M-CA-SS-ED-RG-4/24-PB-1-020217
....
9:21:00
9:21:10
7.4
5.0
13:21:00
13:21:10
8.3
7.0
13:21:00
13:21:10
2.0
0
13:21:00
13:23:51
Multistep DCP 4 Cleaning sponge
DCP4M-CA-SS-ED-SP-4/24-TC-1-020217
9:28:00
9:28:00
9:28:10
24.5
21
13:28:00
13:28:10
36.9
35
13:28:00
13:28:10
19.9
19
13:28:00
13:30:40
DCP4M-CA-SS-ED-SP-4/24-TC-2-020217
9:35:00
9:35:00
9:35:10
27.2
25
13:35:00
13:35:10
17.3
14
13:35:00
13:35:10
12.1
11
13:35:00
13:37:50
DCP4M-CA-SS-ED-SP-4/24-TC-3-020217
9:42:00
9:42:00
9:42:10
40.6
38
13:42:00
13:42:10
17.0
13
13:42:00
13:42:10
11.5
11
13:42:00
13:44:39
DCP4M-CA-SS-ED-SP-4/24-PB-1-020217
....
9:49:00
9:49:10
30.6
27
13:49:00
13:49:10
38.0
34
13:49:00
13:49:10
11.8
12
13:49:00
13:51:35
Multistep DCP 5 Paint roller
DCP5M-CA-SS-ED-PR-4/24-TC-1-020217
9:56:00
9:56:00
9:56:10
12.1*
12
13:56:00
13:56:10
11.4
11
13:56:00
13:56:10
8.5
14
13:56:00
13:58:50
DCP5M-CA-SS-ED-PR-4/24-TC-2-020217
10:03:00
10:03:00
10:03:10
8.2
8.0
14:03:00
14:03:10
17.7
17
14:03:00
14:03:10
10.6
10
14:03:00
14:05:52
DCP5M-CA-SS-ED-PR-4/24-TC-3-020217
10:10:00
10:10:00
10:10:10
9.1
8.0
14:10:00
14:10:10
16.9
17
14:10:00
14:10:10
9.4
9
14:10:00
14:12:35
DCP5M-CA-SS-ED-PR-4/24-PB-1-020217
....
10:17:00
10:17:10
4.6
4.0
14:17:00
14:17:10
13.6
13
14:17:00
14:17:10
7.6
6
14:17:00
14:19:41
*No analytical notes on reason for the high loading; not an outlier
65
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Table A-9. Calculated risk-based surface cleanup thresholds for malathion and carbaryl.
Malathion surface cleanup threshold (noncancer)*
Surface
(ug/100 cm2)
(mg/m2)
Child
Nonporous
2.92
0.29
Porous
14.6
1.5
Adult
Nonporous
17.0
1.7
Porous
85.1
8.5
Carbaryl surface cleanup threshold (noncancer)*
Surface
(|jg/100 cm2)
(mg/m2)
Child
Nonporous
14.6
1.5
Porous
73.1
7.3
Adult
Nonporous
85.1
8.5
Porous
426
43
*THQ = 0.1; equations for risk-based calculations are below
Risk-based surface goal for non-carcinogens:
Adopted from reference [19]:
„ r ^ i , , ^	Target hazard quotient
Risk-based Surface GoalN (juglcm~) =	[A1]
Noncancer hazard0ral + Noncancer hazard Derma]
Noncancer hazard from oral exposure:
\ j(f j) xEDxEF xMCF x STF x UC xMSA xMF xSExET
Noncancer Hazardn, =1—:—		 [A21
BWxATn x TCF
Noncancer hazard from dermal exposure:
1 RfD xEDxEFx MCF x STF xUCxCRx ABSd xET
Noncancer Hazard,			 = ^—-—		 [A3]
Dermal	BW x ATN x TCF
where:
RfDD = RfD0 x ABS GI [A4]
66
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Equation Parameters and Values
Exposure Scenario
Parameter Definition
ED	Exposure duration (years)
EF
MCF
STF
UC
MSA
MF
SE
ET
BW
Exposure frequency (days/year)
Mass conversion factor (mg/|jg)
Skin transfer factor (unitless)
Unit concentration (|jg/cm2)
Mouthing surface area (cm2/event)
Mouthing frequency (events/hour)
Saliva extraction factor (unitless)
Exposure time (hours/day)
Body weight (kg)
Industrial
25
250
0.001
0.25 nonporous
0.05 porous
1.0
45
0.5
80
Residential
6 Child
24 Adult
350
0.001
0.25 nonporous
0.05 porous
1.0
15 Child
45 Adult
39 Age Adj.
9 Child
2 Adult
3.4 Age Adj.
0.5
16
15 Child
80 Adult
59 Age Adj.
Reference
a,b,c
a,b,c
d
a,b,c
ATn
TCF
CR
Average time for noncarcinogens (years)
Time conversion factor (days/year)
Contact rate (cm /hour)
25
365
2000
6 Child
24 Adult
365
2000
a,b,c
a,b,c
b
ABSgi
ABSd
RfD0
RfDn
Gastrointestinal absorption factor (unitless)
Dermal absorption factor (unitless)
Oral reference dose (mg/kg-day)
Dermal reference dose (mg/kg-day)
Chemical-
specific
Chemical-
specific
Chemical-
specific
Calculated
1 (malathion)
1 (carbaryl)
0.1 (malathion)
0.1 (carbaryl)
0.02 (malathion)
0.1 (carbaryl)
Calculated
f
g
Eq. A4
67
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Table References:
a	U.S. Environmental Protection Agency (USEPA), 1991, Risk Assessment Guidance for Superfund,
Vol. 1: Human Health Evaluation Manual, Part B, Development of Risk-Based Preliminary
Remediation Goals. Office of Emergency and Remedial Response, Washington, DC. EPA/540/R-
92/003 https://www.epa.gov/risk/risk-assessment-guidance-superfund-rags-part-b Last
accessed October 19, 2017
b U.S. Environmental Protection Agency (USEPA), 2004, Risk Assessment Guidance for Superfund,
Vol. 1: Human Health Evaluation Manual, Part E, Supplemental Guidance for Dermal Risk
Assessment. Office of Superfund Remediation and Technology Innovation, Washington, DC.
EPA/540/R/99/005 https://www.epa.gov/risk/risk-assessment-guidance-superfund-rags-part-e
Last accessed October 19, 2017
c	U.S. Environmental Protection Agency (USEPA), 2002, Supplemental Guidance for Developing
Soil Screening Levels for Superfund Sites. Office of Solid Waste and Emergency Response,
Washington DC. OSWER 9355.4-24 https://www.epa.gov/superfund/superfund-soil-screening-
guidance Last accessed October 19, 2017
d U.S. Environmental Protection Agency (USEPA), 2003, World Trade Center Indoor Environment
Assessment: Selecting Contaminants of Potential concern and Setting Health-Based
Benchmarks. Prepared by the Contaminants of Potential Concern (COPC) Committee of the
World Trade Center Indoor Air Task Force Working Group.
http://www.epa.gov/WTC/copc studv.htm Last accessed October 19, 2017
e U.S. Environmental Protection Agency (USEPA), 2011, Exposure Factors Handbook: 2011 Edition,
Chapter 8, Body Weight Studies. Office of Research and Development, Washington, DC.
EPA/600/R-09/052F https://cfpub.epa.gov/ncea/risk/recordisplav.cfm?deid=236252 Last
accessed October 19, 2017
f	Oak Ridge National Laboratory (ORNL), 2005, Risk Assessment Information System, Oak Ridge
National Laboratory, Life Science Division, Oak Ridge, TN. https://rais.ornl.gov/ Last accessed
October 19, 2017
g U.S. Environmental Protection Agency (USEPA), 2017, Regional Screening Level Summary Tables
June 2017. https://www.epa.gov/risk/regional-screening-levels-rsls Last accessed October 19,
2017
68
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Table A-10. Concentration of malathion in cleaning media (solid waste), liquid waste, and post-
cleanup surface concentration - all mechanical cleaning media (DCP deployed using water only)
Cleaning Medium Used
Sponge
Cloth
Paint Roller
TvDe of SamDle
Malathion Concentration per Area Cleaned
(mg/m2)
Cleaning media (solid waste)
28
20
<5.4
43
13
<5.4
10
<5.4
<5.4
Mean
26.9
12.7
<5.4
±SD
16.17
7.27
NA
%RSD
60%
57%
NA
Liquid waste
4.2
4.5
1.8
4.5
3.8
1.4
7.0
5.8
2.7
Mean
5.2
4.7
2.0
±SD
1.5
1.03
0.66
%RSD
29%
22%
33%
Surface concentration post-cleaning*
34
22
44
30
32
32
36
34
35
Mean
33
29
37
±SD
3.1
6.6
6.4
%RSD
9.3%
23%
17%
*Cleaning with water only, no decontaminant.
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Table A-11. Concentration of carbaryl in cleaning media (solid waste), liquid waste, and post-
cleanup surface concentration - all mechanical cleaning media (DCP deployed using water-only)
Cleaning Medium Used
Sponge
Cloth
Paint Roller
Type of Sample
Carbaryl Concentration per Area Cleaned


(mg/m2)

Cleaning media (solid waste)
81
140
<5.4
111
32
<5.4
60
95
<5.4
Mean
84.0
89.2
<5.4
±SD
25.6
54.1
NA
%RSD
31%
61%
NA
Liquid waste
3.6
<0.11
No sample**
1.5
<0.11
0.75
2.0
<0.11
0.64
Mean
2.4
<0.11
0.69
±SD
1.1
NA
0.08
%RSD
46%
NA
12%
Surface concentration post-cleaning*
91
100
No sample**
76
336
83
115
139
82
Mean
94
190
83
±SD
20
130
0.70
%RSD
21%
66%
0.8%
*Cleaning with water-only, no decontaminant; **Due to sample mislabeling error
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Appendix B: Wipe Sampling Procedure
The details on the wipe sampling procedure are for a surface that is 12 in x 12 in. Note:
Photographs are showing hexane-based wipe sampling; for acetone sampling used in the optimized method
in this study, latex gloves were worn over nitrile gloves.
This multistep sampling procedure is summarized below:
1.	Prepare sampling wipes:
•	Don disposable nitrile gloves.
•	Using forceps, remove one clean wipe from the storage container and place it on a clean
Petri dish.
•	Pipette 3 ml_ of wetting solvent (IPA, hexane, acetone, etc.) onto the center of the wipe,
cover the dish, and allow the solvent to disperse into the wipe material.
•	Proceed immediately to wipe sampling.
2.	Don a fresh pair of nitrile gloves.
3.	Grasp the wetted decontamination wipe with one hand, and use the other hand to gently fold
the wipe (Figure B-1). Do not squeeze the wipe to avoid loss of the wetting solvent.

Figure B-1. Folding wipe for sampling the first wiping pathway (horizontal).
4. Starting in the top left corner, wipe the surface horizontally, working downward, to cover the
surface completely. The horizontal wipe sampling pathway is shown in Figure B-2.
71
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r\
Figure B-4. Vertical wiping pathway.
7. Using both hands, gently refold the wipe diagonally, so that that surface used for the vertical
Figure B-2. Horizontal wiping pathway.
5. Using both hands, gently refold the wipe so that that the surface used for the horizontal wipe
sampling is now on the inside (Figure B-3).
Figure B-3. Folding wipe for sampling the second wiping pathway (vertical).
6. Starting in the bottom left corner, wipe the surface vertically, working toward the right, to
completely cover the surface. The vertical wipe sampling pathway is shown in Figure B-4,
72
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wipe sampling is now on the inside (Figure B-5).
Figure B-5. Folding wipe for sampling the third wiping pathway (diagonal).
8. Starting in the top left corner, wipe the surface diagonally, working toward the bottom right
corner, to completely cover the surface. The diagonal wipe sampling pathway is shown in
Figure 4-6.
Figure B-6. Diagonal wiping pathway.
Using both hands, gently refold the wipe so that that surface used for the diagonal wipe sampling is
now on the inside (Figure B-7).
73
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Figure B-7. Folding wipe for sampling the fourth pathway (perimeter).
9. Starting in any corner, wipe the perimeter of the coupon. The perimeter wipe sampling pathway
is shown in Figure B-8.
I
o
0
o
o
o
o
0
o
o
o
o
0
o
o
o
o
o
o
o
o
1
Figure B-8. Perimeter wiping pathway.
10. Repeat steps 1-9 for repeated wipe sampling of the same surface area.
74
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Appendix C: Method Development for Liquid Waste
Extraction
Liquid waste in this study was extracted using the modified extraction procedure described in EPA
Method 3571 (Extraction of Solid and Aqueous Samples for Chemical Agents) [8], The method-
recommended extraction solvent of 10% IPA/dichloromethane was replaced with hexane. Method
performance was demonstrated using simulated liquid waste samples (water only, no decontaminant;
addition of soap to optimize for detergent-containing samples) spiked with malathion solutions. Two target
concentrations (low and high) were tested in these matrix spike samples: 0.05 mg/mL and 5 mg/mL. There
were six samples for each target chemical-concentration combination, three with preservative (L-ascorbic
acid, ethylenediaminetetraacetic acid) added and three without preservative, accompanied by one PB, total
of twelve samples. There was one solvent blank sample (hexane). The preservation-no-preservation test
design is below:
1.	Six samples, three at 0.05 mg/L and three at 5 mg/L concentration, were preserved with L-ascorbic
acid, ethylenediaminetetraacetic acid, and pH-adjusted with the trisodium salt of potassium
dihydrogen citrate to pH 3.8 to slow alkaline hydrolysis of malathion. Metabolites of malathion
resulting from hydrolysis include malaoxon, malathion alpha and beta monoacid, diethyl fumarate,
diethyl thiomalate, 0,0-dimethylphosphorodithioic acid, diethylthiomalate, and 0,0-
dimethylphosphorothionic acid) [9],
2.	Preserved samples were each spiked with 30 |jL of 20x concentrated L-ascorbic acid,
ethylenediaminetetraacetic acid, and pH-adjusted with the trisodium salt of potassium dihydrogen
citrate solutions. Six samples, three at 0.05 mg/L and three at 5 mg/L concentration, were prepared
without preservatives. In this study, liquid preserved and unpreserved samples were extracted with
5 mL of hexane immediately after collection to avoid losses of target chemicals. Hexane extracts
were analyzed for malathion via GC/MS.
75
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vvEPA
United States
Environmental Protection
Agency
PRESORTED STANDARD
POSTAGE & FEES PAID
EPA
PERMIT NO. G-35
Office of Research and Development (8101R)
Washington, DC 20460
Official Business
Penalty for Private Use
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