EPA/600/R-00/029

February 2000

Dermal Transfer Efficiency of 

Pesticides from New, Vinyl Sheet

Flooring to Dry and Wetted Palms

by

Jackie M. Clothier

Southwest Research Institute

San Antonio, Texas 78228

Contract Number 68-DO-0049

Work Assignment Manager

Robert G. Lewis

Human Exposure & Atmospheric Sciences Division

National Exposure Research Laboratory

Office of Research and Development

U.S. Environmental Protection Agency

Research Triangle Park, NC 27711
ii

Notice

The U.S. Environmental Protection Agency through its Office of Research and Development

funded and managed the research described here under contract 68-D5-0049 to ManTech

Environmental Technology, Inc., and ManTech’s subcontract 96-0049-01 to Southwest Research

Institute. It has been subjected to the Agency’s peer and administrative review and has been

approved for publication as an EPA document. Mention of trade names or commercial products does

not constitute endorsement or recommendation for use.
iii

Foreword

The National Exposure Research Laboratory, Research Triangle Park, North Carolina,

conducts intramural research in the chemical, physical, and biological sciences. This research is

intended to characterize and quantify ambient air pollutant levels and the resulting exposures of

humans and ecosystems; to develop and validate models to predict changes in air pollution levels; to

determine source–receptor relationships affecting ambient air quality and pollutant exposures; and

to solve problems relating to EPA's mission through long-term investigation in the areas of

atmospheric methods, quality assurance, biomarkers, spatial statistics, exposure assessment, and

modeling. The laboratory provides support to Program and Regional offices and state and local

groups in the form of technical advice, methods research and development, quality assurance, field

monitoring, instrument development, and modeling for quantitative risk assessment and regulation.

The laboratory also collects, organizes, manages, and distributes data on air quality, human and

ecosystem exposures and trends for the Program and Regional offices, the Office of Research and

Development, the scientific community, and the public.

The information in this research report was obtained using existing methods, as well as

methods that were developed specifically for this study, to determine the transfer efficiencies of

pesticide residues on vinyl floor covering to dry and wetted human skin. This information is needed

for better the understanding of the bioavailability of residential pesticide residues and assessments of

the potential for human exposures to pesticides used around the home.

Gary J. Foley

Director

National Exposure Research Laboratory

Research Triangle Park, NC 27711
iv

Abstract

This report presents results of a study to determine the transfer efficiencies from sheet vinyl flooring

to human skin of three pesticides commonly used for residential indoor insect control. Formulations

of the insecticides chlorpyrifos, pyrethrin I and piperonyl butoxide were applied to new, sheet vinyl

flooring by broadcast spray and allowed to dry for four hours. Deposition coupons were used to

estimate initial surface loadings and the PUF Roller was to measure dislodgeable residues. After the

4-hour drying period, adult volunteers performed hand presses (left and right hands, palm only) with

either dry or wetted skin. Water and the participant’s own saliva were used as wetting agents.

Transfer efficiencies for wetted palms were 2.5 to 3.5 times higher than those for dry palms. The

mean (six presses) transfer efficiencies for chlorpyrifos were 5.22% for water-wetted (W), 4.38% for

saliva-wetted (S), and 1.53% for dry skin (D). Similar transfer efficiencies were measured for

piperonyl butoxide: W - 4.8%, S - 4.1%, and D - 1.4%. Transfer efficiencies for pyrethrin I were

about twice as high as those for the other two pesticides: W - 11.9%, S - 8.9%, and D - 3.6%. 
v

Contents

Section Page

Figure .............................................................. v

Tables ............................................................. vi

 1. Introduction .......................................................... 1

 2. Conclusions and Recommendations ........................................ 1

 3. Experimental Methods .................................................. 2

3.1 Informed Consent ................................................ 2

3.2 Test Procedures .................................................. 2

 3.2.1 Palm Moistening Procedure .................................. 2

3.2.2 Palm Press and Wipe Procedure ............................... 3

3.2.3 PUF Roller Method ......................................... 3

3.2.4 Broadcast Application of Formulated Mixture ..................... 4

 4. Experimental Design ................................................... 4

4.1 Field Procedures ................................................. 5

4.2 Sample Extraction and Analysis ...................................... 6

4.3 Data Evaluation .................................................. 6

 5. Results and Discussion .................................................. 6

5.1 Data Quality .................................................... 6

5.2 Single Press Transfer of Pesticides from New, Treated Vinyl Sheet Flooring to

Human Palm .................................................... 6

5.3 Moistened and Dry Palm Transfer Efficiency ............................ 7

5.4 Transfer of Pesticides from New, Treated Vinyl Sheet Flooring to Polyurethane 

Foam (PUF) Rings ................................................ 7

 6. References ........................................................... 8

Figure

 1 Scaled layout for palm press, PUF roller, and deposition coupon sampling on one

4-ft. × 5-ft. section of treated vinyl showing location of samples collected for Day 0

and Blocks 1L, 1R, and 2 on Days 1 and 2 ................................... 9
vi

Tables

Number Page

 1 Ratio of Moistened to Dry-Palm Transfer Efficiencies of Pesticides from One Press

onto New, Vinyl Sheet Flooring Treated by Broadcast Application (Mean ± Std.

Dev. of Six Replicates, %) ............................................. 10

 2 Transfer Efficiency (%) of Chlorpyrifos from New, Vinyl Sheet Flooring by Single

Press of Human Palm Which was Dry or Moistened with Water or Human Saliva ... 11

 3 Transfer Efficiency (%) of Pyrethrin I from New, Vinyl Sheet Flooring by Single

Press of Human Palm Which was Dry or Moistened with Water or Human Saliva ... 12

 4 Transfer Efficiency (%) of Piperonyl Butoxide from New, Vinyl Sheet Flooring by

Single Press of a Dry or Moistened Palm .................................. 13

 5 Transfer Efficiency (%) of Pesticides from Treated, New, Vinyl Sheet Flooring onto

PUF Roller and Dry Palm after Single Press ............................... 14

 6 Comparison of Palm Transfer Rates of Chlorpyrifos, Pyrethrin I and Piperonyl Butoxide 

from Day 3 of Experiment 6.2 Using Plush Carpet and Experiment 7 Using 

Vinyl Sheeting ...................................................... 15

 7 Design for the Transfer Efficiency Test on New, Vinyl Sheet Flooring (Task 7) ..... 16

 8 Isopropanol Gauze Palm Wipe, PUF Ring, and Deposition Coupon Blanks ........ 17

 9 Recovery of Target Analytes from Matrix Spikes ........................... 18

10 Comparison of Chlorpyrifos Transfer from New, Vinyl Sheet Flooring by Single Press 

of Human Palm (Dry and Moist) ........................................ 19

11 Comparison of Pyrethrin I Transfer from New, Vinyl Sheet Flooring by Single Press

of Human Palm (Dry and Moist) ........................................ 20

12 Comparison of Piperonyl Butoxide Transfer from New, Vinyl Sheet Flooring 

by Single Press of Human Palm (Dry and Moist) ............................ 21

13 Transfer Amount of Pesticides from Treated, New, Vinyl Sheet Flooring onto PUF

Roller and Dry Palm after Single Press ................................... 22

14 Transfer Rate of Pesticides from Treated, New, Vinyl Sheet Flooring onto PUF

Roller and Dry Palm after Single Press ................................... 23
1

Section 1

Introduction

Surface residues of pesticides in residential environments present a major potential risk for

young children. The hands of infants and toddlers are often wet with saliva from frequent hand-tomouth activity. Thus their hands may dislodge pesticide residues from surfaces more efficiently than

the dry hands of adults. Preliminary studies have shown that presses with saliva-wetted hands give

larger transfers of pesticides from new cut-pile nylon plush carpet than do presses with dry hands

(Camann et al., 1996). The consistency of pesticide transfer differences between saliva-wetted and

dry hands has been investigated for new and used cut-pile carpets. The same investigation must be

performed on vinyl flooring and grass. It is also important to determine if the pesticide transfers with

water-wetted hands are similar to those with saliva-wetted hands.

The objective of Task 7 of Work Assignment III-76 is to compare the press transfers of freshlyapplied pesticide residues from treated vinyl flooring to palms of hands which are saliva-wetted,

water-wetted, and dry. The focus is on pesticides approved for use on indoor surfaces (i.e.,

chlorpyrifos, pyrethrins, and piperonyl butoxide). For the experiment, a formulated mixture,

Dursban® plus Kicker®, is applied, since it contains all three pesticides of interest. 

This protocol describes experimentation for Task 7, in which press transfer efficiencies are

compared for a dry palm, palms wetted with human saliva (HS) and water, and a dry PUF roller onto

a section of new, vinyl sheet flooring which was recently treated with chlorpyrifos, pyrethrins, and

piperonyl butoxide.

Section 2

Conclusions and Recommendations

Considering measurement variation, one dry palm press gave essentially the same mean (n = 6)

transfer efficiency for chlorpyrifos (1.53%) and piperonyl butoxide (1.41%) with considerably higher

transfer efficiency for pyrethrin I (3.64%). The increased transfer with a moistened palm press relative

to a dry palm press is shown in Table 1 to be the same (3.4-fold) for all three pesticides when water

is the moistening agent and 2.4 to 3-fold for all three pesticides when saliva is the moistening agent.

Considerable loss of pesticide residue transfer occurs with time, possibly because of increased

adhesion to the vinyl surface. The loss is independent of dislodgeable residue method and wetting

agent. When averaging all palm wipe samples in Tables 2 through 4, losses in transfer efficiency on

the second day after application are 58.5% for chlorpyrifos, 63.5% for pyrethrin I, and 61.2% for

piperonyl butoxide. When averaging losses in PUF transfer efficiency (Table 5) very similar results

are obtained: 63% for chlorpyrifos, 54% for pyrethrin I, and 64% for piperonyl butoxide.

The acceptable use of the PUF roller as a mechanical means of approximating dermal exposure

to pesticides from floors is further supported by results of this study. Comparing the mean (n=6)

transfer efficiency of the PUF roller with dry hand presses (Table 5), the PUF roller method gives
2

between 1 and 3 times higher residue removal than a dry palm press but residue removal similar to

that achieved with moistened palms. 

When comparing transfer efficiencies of dislodgeable residue passed to palms when in contact

with pesticide-laden, new carpet (Experiment 6.1) and new, vinyl sheet flooring, the amount of

pesticide residue removed from the vinyl floor is considerably higher than that removed from the

carpet. Based on experimental design and deposition coupon loadings, both surfaces were loaded with

similar amounts of chlorpyrifos (3775 ng/cm2 vinyl and 3110 ng/cm2 carpet). However, three times

more chlorpyrifos was removed from vinyl than was removed from plush carpet with a dry or wetted

hand. For pyrethrin I, eleven times more residue was removed from vinyl with dry palms and five

times more with wetted palms than was removed from carpet. For piperonyl butoxide, two to three

times more residue was removed from vinyl with either dry or wetted palms than was removed from

carpet. This finding was expected because carpet fibers provide more surface area for the residues

to adhere. Table 6 summarizes data from application Day 3 of both Experiment 6.2 (used, plush

carpet) and Experiment 7 (vinyl). 

Section 3

Experimental Methods

3.1 Informed Consent

A protocol which described the experiment and a consent form were prepared and approved

by the Institutional Review Board of the University of Texas Health Science Center in San Antonio.

Three healthy male subjects who are supervisory employees at Southwest Research Institute

volunteered to perform the palm presses. Informed consent of each volunteer subject was obtained.

3.2 Test Procedures

An empty 7' × 7' carpeted area in a 3-room trailer on the SwRI campus was used to do the

experiment. Two 5' × 6' sections of new, Armstrong Cambray vinyl sheet flooring (A and B) were

laid over the existing carpet and attached using tape. 

3.2.1 Palm-Moistening Procedure

Each subject collected 5 mL of his own saliva in a Teflon bottle for use in moistening his palm with

HS for some of the field sampling palm presses. The salivary fluids were stored at 4EC.

A 3.5-in. × 3.5-in. (8.9-cm × 8.9-cm ) square central area of the clean bare palm of the test hand

was moistened by pressing the palm onto a polyethylene surface, which was supported by small bubble

wrap and on which 250 μL of the salivary fluid had been placed. The wetted surface was prepared by

spiking about six drops of the fluid in the central portion of a 3.5 in. (8.9 cm) diameter circular area

outlined on the underside of a polyethylene sheet. Immediately, the subject placed the palm over the wetted

area and rotated the hand with moderate pressure back and forth (to the left and to the right) about six

times to transfer and achieve a uniform coating of the fluid over the center of the palm. Within 6 to 10
3

seconds after moistening, the subject performed a single press of the moistened palm onto the test surface.

3.2.2 Palm Press and Wipe Procedure

A single press of the treated vinyl sheet was made in a reproducible manner with a palm after

receiving the designated treatment [i.e., none (dry), water-moistened, or HS-moistened]. Prior to each

daily pair of palm presses, each subject thoroughly washed his hands with soap and water. The subject

was cautioned to avoid touching any extraneous surfaces during the palm-press-and-wipe sequence.

The subject then placed a disposable powder-free latex glove over the non-test hand. The second

hand was gloved to prevent contamination while performing the moistening, press, and wipe

procedures with the first hand and to prevent the isopropanol wipe from abnormally drying the skin

of the second hand prior to its use for a hand press. The test hand was given the designated treatment,

moistening when specified as described above. A clean card-stock template (8.5-in. × 11-in. cardstock, with a 3.5-in. × 3.5-in. area cut out) was placed over the designated area to expose a 12.25

in.2 (79.2 cm2) area of vinyl. While kneeling on a cardboard mat, each subject performed one press

of the palm of the test hand, with fingers extended above the template, onto the 79.2 cm2 area of

carpet exposed through the template, for 1 sec. at a pressure of ca. 1.0 psi (6,900 Pa). After all

subjects had conducted one palm press, each performed a double isopropanol wipe of the test palm

as a modification of Geno et al. (1996a) in a clean area away from the trailer. After washing both

hands with soap and water, the glove was removed from the second hand, and a clean glove placed

over the previously tested hand. The moistening, press, and wipe procedures described above were

then repeated using the palm of the second hand.

The palm wipe procedure used two 4-in. × 4-in. Sof-Wick® 6-ply gauze dressing sponges that

had been precleaned with isopropanol and 1:1 ether:hexane. Each sponge was laced with 10 mL of

isopropanol. The subject performed a general wipe of the palm of the test hand with the first sponge.

The second sponge was used for a more thorough wipe of the entire palm. Both sponges were then

placed in a single container and 25 mL of Baxter pesticide grade methanol was added. The subjects

performed all direct handling of the sponges from preparation through placement in the sample

container, although handling via forceps was also permitted. Immediately following each palm wipe

procedure, the subject thoroughly washed his hands to remove any remaining pesticide residues.

3.2.3 PUF Roller Method

A precleaned dry PUF ring (3-in. length, 3.5-in. OD, 1.62-in. ID) was fitted onto the 3-in.

length × 1.75-in. OD cylindrical aluminum roller of the October 1992 model of the PUF roller sampler

(Camann, 1996b). From a stationary position with the PUF ring setting on aluminum foil, the roller

sampler was pushed or pulled to move the PUF ring over a 3-in. × 3-ft. (696.8 cm2) strip of vinyl

sheeting at 10 cm/sec to make one traverse. After the pass, the PUF ring was removed from the roller

for analysis.
4

3.2.4 Broadcast Application of Formulated Mixture

On both on Day 1 and on Day 3, a broadcast spray of a chlorpyrifos/pyrethrins/piperonyl

butoxide formulation was applied to the test vinyl section by licensed pest control operator following

according to label directions for light infestation flea control. The formulated emulsifiable concentrate

was composed of Dursban® Pro (EPA Registration No. 62719-166), which contained 22.5%

chlorpyrifos, and Kicker® (EPA Registration No. 4816-707AA), which contained 6.0% pyrethrins

and 60.0% technical piperonyl butoxide. It was tank-mixed at 1.33 fl. oz. (40 mL) Dursban® Pro

and 0.5 fl. oz. (15 mL) Kicker® per gallon of water, to yield 0.25% chlorpyrifos, 0.025% pyrethrins,

and 0.25% piperonyl butoxide in the aqueous spray. The mixture was applied approximately 40 cm

above the test surface at a rate of 1 gallon of diluted mixture per 1600 ft2 with a hand-held fan

broadcast nozzle attached to an air-pressurized tank. Application was performed with a smooth backand-forth motion to attempt uniform deposition.

The trailer was maximally ventilated for 2 hours after the application, by opening windows

and the door and through operation of the air conditioning or heating unit in the fresh air mode. The

windows and door were closed and air conditioning/heating returned to the normal recirculated air

mode prior to sampling for the duration of the sampling period. The surface was allowed to dry for

at least four hours before hand presses were performed.

Section 4

Experimental Design

4.1 Field Procedures

Task 7 was performed from October 27, 1998 (Day 0) through November 3, 1998 (Day 4).

The experimental design is presented in Table 7. A PUF roller traverse, a deposition coupon, and a

palm press by each subject were collected from adjacent areas termed a block. The treatment (dry,

water-moistened, or HS-moistened) applied to each palm (left or right) of the three subjects is

specified in Table 7. The layout of PUF roller traverses, deposition coupons, and palm press templates

for all samples collected on one of the sections of treated vinyl over two sampling days is shown in

Figure 1.

Six field method blanks were obtained on a day prior to the pesticide application (Day 0) by

having the three subjects perform a press of each palm using one of the three treatments (for a total

of six blank palm presses) onto designated areas of the untreated vinyl. Before the Dursban and

Kicker mixture was applied, three 4-in. × 4-in. alpha-cellulose pads backed with aluminum foil were

placed on the test area, one at the designated location in each block, as deposition coupons. The PUF

roller pass was performed where designated in a block. Then the deposition coupon in the block were

picked up from the vinyl as a sample just before the three palm presses were performed in that block.

Before the first block of field samples on Day 1 and again after the last block on Day 4, five field

spikes of the target analytes were made: three onto Sof-Wick sponge pairs simulating the three palm
5

treatments [wetted with 100 μL of a moistening fluid (when appropriate) and 20 mL of isopropanol]

and one each onto a PUF ring and a trimmed (3-in. × 3-in.) alpha-cellulose pad.

Replicate sampling commenced upon label-allowed reentry, when the vinyl was dry (defined

operationally as four hours after the application). Two blocks were sampled per day on the

application days (Days 1 and 3) and one block on the succeeding days (Days 2 and 4). Section A was

removed and section B laid down at the conclusion of Day 2 sampling. Only one press and wipe was

permitted per subject palm per day to avoid altering skin transfer characteristics and to limit acute

exposure of subjects.

A total of six replicate presses of each palm treatment were collected. Each of the three

subjects thoroughly washed his hands with dispenser soap and water, dried them, and gloved the hand

which was not to be used for pressing. After treating the palm as specified in Table 7, each subject

made one press of the treated palm onto a 79.2 cm2 area of treated vinyl through a clean cardstock

template. As specified in Table 7, each subject had a different moistening or dry treatment of the palm

of the same hand for the three palm presses onto designated areas of the vinyl comprising a block.

The double isopropanol-gauze wipe method was used to wipe the residue from the pressed palm. On

Days 1 and 3, after removing the glove, each subject had his other palm treated in the specified

manner, pressing it through a clean template onto the vinyl.

4.2 Sample Extraction and Analysis

Wipe samples were cold-shake extracted for neutral pesticides as described in Geno et al.

(1996), according to SwRI SOP 01-17-08, “Extraction of Neutral Pesticides, Acid Herbicides, and

Phenols from Isopropanol Wipes”. Extracts were cleaned through a Florisil column. The extraction

procedure involved adding terphenyl-d14 as a recovery surrogate to the sample jar, shaking for 30 min

on a mechanical shaker, then decanting the methanol, and shaking the dressing sponges twice more

for 1 min, each time with 50 mL portions of 1:1 ether:hexane. The sponges were squeezed, all solvent

fractions combined, and concentrated in a N-Evap® vessel to a final volume of 20 mL in 10% ether

in hexane. Wipe samples of dry palm presses and field and lab blanks were concentrated to a 5.0 mL

final volume in 10% ether in hexane so as to lower the detection limits of chlorpyrifos and piperonyl

butoxide to 0.10 μg/extract.

The aluminum foil backing and the 0.5-in. border was removed from each deposition coupon

to leave a 3-in. × 3-in. alpha-cellulose pad. PUF rings and 3-in. × 3-in. alpha-cellulose pads were

soxhlet-extracted with 6% ethyl ether/94% hexane. All extracts were analyzed for chlorpyrifos,

pyrethrin I, and piperonyl butoxide on a Fisons MD 800 or HP 5973 GC/MS operating in selected

ion monitoring mode according to SwRI SOP 01-17-02, “Determination of Pesticides, Acid

Herbicides, Phenols, and PAHs by GC/MS”.
6

4.3 Data Evaluation

The loadings of the three applied pesticides on the treated vinyl at the time of sampling were

estimated from the loading on adjacent deposition coupons: μg on coupon/coupon surface area (58.1

cm2). Palm press transfer rates (ng/cm2) were calculated as the amount (ng) obtained with the

isopropanol palm wipe divided by vinyl area pressed (79.2 cm2). PUF roller transfer rates (ng/cm2)

were calculated as the amount (ng) obtained from one traverse divided by the area of vinyl traversed

(696.8 cm2). The mean and standard deviation of the transfer efficiencies (%) ( = transfer rate/carpet

loading) were determined from the six replicates for each analyte and palm treatment.

Section 5

Results and Discussion

5.1 Data Quality

The amounts of chlorpyrifos, pyrethrin I and piperonyl butoxide found in the field blanks

(collected on Day 0) and the lab blanks are presented in Table 8. Essentially, no chlorpyrifos,

pyrethrin I or piperonyl butoxide was detected above the detection limit in any lab blank. All field

blanks (including two PUF rings and six isopropanol gauze wipes) showed no detectable amounts of

chlorpyrifos, pyrethrin I, or piperonyl butoxide. Therefore, adjustment of data collected on samples

from treated vinyl were unnecessary. 

Recoveries of chlorpyrifos, pyrethrin I, and piperonyl butoxide from field and lab matrix

spikes of isopropanol gauze, PUF rings, and deposition coupons are given in Table 9. Recovery of

chlorpyrifos, pyrethrin I, and piperonyl butoxide from PUF rings was quantitative. The type of

moistening treatment (i.e., palms pressed dry or moistened with water or human saliva) appear to

have no effect on recovery of target compounds from gauze wipe samples. The average of six

recoveries of chlorpyrifos, pyrethrin I, and piperonyl butoxide from gauze wipe spikes was 92.8%,

112.0%, and 95.6%, respectively. Field-spiked deposition coupons show poorer recoveries, possibly

because the 0.5-in. border of the coupon was not removed prior to spiking, resulting in some loss of

target compounds when the border was removed prior to extraction. The efficiency of Soxhlet

extraction using deposition coupons in previous experiments has previously been very good as is also

demonstrated by 80-100% recoveries using laboratory matrix spikes. 

5.2 Single Press Transfer of Pesticides from New, Treated Vinyl Sheet Flooring to Human

Palm

The amounts of chlorpyrifos, pyrethrin I, and piperonyl butoxide recovered from each

deposition coupon and the calculated surface loadings on the treated vinyl during each set of palm

presses are shown in Tables 10, 11, and 12, respectively. The surface loading for Day 4 is an estimate

calculated by subtracting the coupon matrix spike from the deposition coupon which was

inadvertently spiked with pesticide. Coupon amounts indicate the broadcast application on Days 1
7

and 3 gave similar loadings of the applied pesticides to the vinyl. The amounts wiped from each

subject’s palm after it had been pressed once, while dry or wetted onto the treated vinyl are also

shown in Tables 10 through 12. The vinyl-to-palm transfer rate calculated from each palm wipe

amount is also presented in Tables 10 through 12, along with the mean and standard deviation of the

transfer rates for dry palms and each palm wetting agent. 

5.3 Moistened and Dry Palm Transfer Efficiency

Tables 2, 3, and 4 show palm wipe transfer efficiencies of chlorpyrifos, pyrethrin I, and

piperonyl butoxide using dry and wetted palms. Means and standard deviations are reported for six

samples collected over four days. However, because there appears to be an increased adhesion of the

pesticide formulation to the vinyl after 24 hours, statistical comparisons are also made between

samples collected on Days 1 and 3 (n = 4) and Days 2 and 4 (n = 2). This observation is apparent in

the amount of pesticide detected both in PUF rings and isopropanol gauze palm wipes, regardless of

moistening treatment. A similar trend occurred in dislodgeable residue studies on vinyl sheeting

conducted by SwRI in 1993 (Comparison of Methods to Determine Dislodgeable Residue Transfer

From Floors, EPA Contract 68-DO-0007). This trend is also summarized in Tables 2 through 4. 

Mean (± standard deviation) transfer efficiencies of chlorpyrifos were 5.22% ± 3.02% for

water-wetted palms, 4.38% ± 2.83% for saliva-wetted palms, and 1.53% ± 0.73% for dry palms. The

same relationship was observed for pyrethrin I and piperonyl butoxide mean transfer efficiencies:

largest for water-wetted palms, slightly less for saliva-wetted palms and substantially lower for dry

palms. The large standard deviations indicate no appreciable differences between the mean pesticide

transfer efficiencies with a saliva-moistened and a water-moistened palm. This finding suggests that

it is the wetness of the saliva rather than its stickiness/viscosity that is primarily responsible for the

enhanced pesticide transfer from a treated sheet of vinyl through contact with a saliva-wetted palm,

compared to a dry palm.

5.4 Transfer of Pesticides from New, Treated Vinyl Sheet Flooring to Polyurethane Foam

(PUF) Rings

The amounts and transfer rates of chlorpyrifos, pyrethrin I, and piperonyl butoxide recovered

from PUF rings and dry palm press hand wipes are shown in Tables 13 and 14. Transfer efficiencies

are listed in Table 5, however, because of the noticeable loss in amount of transfer from fresh to day

old treatment, efficiency measurements are also included for Days 1 and 3 compared with Days 2 and

4 for all three pesticides. PUF ring transfer efficiencies reported from the 1993 study are also

included.
8

References

Camann DE, Majumdar TK, Harding HJ, Ellenson WD, and Lewis RG. “Transfer efficiency of

pesticides from carpet to saliva-moistened hands.” In: Measurement of Toxic and Related Air

Pollutants, VIP-64, Air and Waste Management Association, Pittsburgh, PA, 532-540, 1996a.

Camann DE, Harding HJ, Geno PW, and Agrawal SR. Comparison of Methods to Determine

Dislodgeable Residue Transfer from Floors. EPA/600/R-96/089, U.S. Environmental Protection

Agency, Research Triangle Park, NC, 1996b.

Geno PW, Camann DE, Harding HJ, Villalobos K, and Lewis RG. Handwipe sampling and analysis

procedure for the measurement of dermal contact with pesticides. Arch Environ Contam Toxicol, 30,

132-138, 1996.
9

1R 1R 1R 1R

1L 1L 1L 1L

2 2 2 2

1L 1R

Note: 0 indicates location of Day 0 Field Blanks

VINYL SECTION

2

0

Figure 1. Scaled layout for palm press, PUF roller, and deposition coupon sampling on

one 4-ft. × 5-ft. section of treated vinyl showing location of samples collected

for Day 0 and Blocks 1L, 1R, and 2 on Days 1 and 2.
10

Table 1. Ratio of Moistened to Dry-Palm Transfer Efficiencies of Pesticides from

One Press onto New, Vinyl Sheet Flooring Treated by Broadcast

Application (Mean ± Std. Dev. of Six Replicates, %)

Hand Condition Chlorpyrifos Pyrethrin I

Piperonyl 

 Butoxide

Dry 1.0 ± 0.48 1.0 ± 0.61 1.0 ± 0.52

Moistened with:

Water

Human Saliva

3.4 ± 2.0

 2.9 ± 1.8

3.3 ± 2.0

 2.4 ± 1.3

3.4 ± 2.1

2.9 ± 1.9
11

Table 2. Transfer Efficiency1 (%) of Chlorpyrifos from New, Vinyl

Sheet Flooring by Single Press of Human Palm Which was

Dry or Moistened with Water or Human Saliva

Block Dry Water-Wetted

SalivaWetted

1993

Vinyl

Study2

1L

1R

2.04

1.65

6.74

7.97

1.81

4.90

2L 0.83 1.53 2.60

3R

3L

1.35

2.62

5.24

8.24

3.75

9.74

4R 0.71 1.61 3.48

No. Samples, n

Mean, 0

Std. Dev., s

6

1.53

0.73

6

5.22

3.02

6

4.38

2.83

Comparison of Wipes From Application Days 1

and 3

No. Samples, n

Mean, 0

Std. Dev., s

4

1.92

0.55

4

7.05

1.37

4

5.05

3.38

6

4.70

3.31

Comparison of Wipes From Days 2 and 4

No. Samples, n

Mean, 0

Std. Dev., s

2

0.77

0.08

2

1.57

0.06

2

3.04

0.62

6

2.05

1.04

% Loss 60 78 40 56

1 Transfer Efficiency, % = 100 × (transfer rate, ng/cm2

)/(mean surface loading,

ng/cm2)

2 Dry palm presses were conducted on 8-10-93, after pesticide application and

again the following day.
12

Table 3. Transfer Efficiency1(%) of Pyrethrin I from New, Vinyl Sheet

Flooring by Single Press of Human Palm Which was Dry or

Moistened with Water or Human Saliva

Block Dry Water-Wetted

SalivaWetted

1993

Vinyl

Study2

1L

1R

6.00

5.04

16.80

19.20

5.52

10.56

2L 1.80 3.12 6.12

3R

3L

2.24

5.78

11.09

17.70

6.72

17.70

4R 1.00 3.30 6.72

No. Samples, n

Mean, 0

Std. Dev., s

6

3.64

2.21

6

11.87

7.25

6

8.89

4.66

Comparison of Wipes From Application Days 1 and

3

No. Samples, n

Mean, 0

Std. Dev., s

4

4.76

1.73

4

16.20

3.54

4

10.13

5.49

6

5.48

1.18

Comparison of Wipes From Days 2 and 4

No. Samples, n

Mean, 0

Std. Dev., s

2

1.40

0.56

2

3.21

0.13

2

6.42

0.42

6

1.81

3.94

% Loss 70 80 37 67

1 Transfer Efficiency, % = 100 × (transfer rate, ng/cm2

)/(mean surface loading,

ng/cm2)

2 Dry palm presses were conducted on 8-10-93, after pesticide application and

again the following day.
13

Table 4. Transfer Efficiency1 (%) of Piperonyl Butoxide from New, Vinyl Sheet

Flooring by Single Press of Human Palm Which was Dry or Moistened

with Water or Human Saliva

Block Dry Water-Wetted Saliva-Wetted

1993

Vinyl Study2

1L

1R

1.84

1.64

5.63

7.16

1.84

4.76

2L 0.72 1.23 2.35

3R

3L

1.16

2.52

5.24

8.41

3.24

9.06

4R 0.59 1.42 3.11

No. Samples, n

Mean, 0

Std. Dev., s

6

1.41

0.73

6

4.85

2.95

6

4.06

2.64

Comparison of Wipes From Application Days 1 and 3

No. Samples, n

Mean, 0

Std. Dev., s

4

1.79

0.56

4

6.61

1.46

4

4.72

3.13

6

6.23

4.69

Comparison of Wipes From Days 2 and 4

No. Samples, n

Mean, 0

Std. Dev., s

2

0.66

0.09

2

1.32

0.13

2

2.73

0.54

6

2.51

1.14

% Loss 63 80 42 60

1 Transfer Efficiency, % = 100 × (transfer rate, ng/cm2

)/(mean surface loading, ng/cm2)

2 Dry palm presses were conducted on 8-10-93, after pesticide application and again the

following day.
14

Table 5. Transfer Efficiency1 (%) of Pesticides from Treated, New, Vinyl Sheet

Flooring onto PUF Roller and Dry Palm After Single Press

Summary of Pesticide Transfer Efficiency Using Dry Palm

Chlorpyrifos Pyrethrin I

Piperonyl

Butoxide

Day PUF

Dry

Palm PUF

Dry

Palm PUF

Dry

Palm

1L2

1R

2.43

7.05

2.04

1.65

4.35

10.61

6.00

5.04

2.26

8.47

1.84

1.64

2L 1.15 0.83 1.90 1.80 0.93 0.72

3R2

3L

5.40

7.64

1.35

2.62

6.55

8.69

2.24

5.78

5.21

7.70

1.16

2.52

4R 1.48 0.71 1.87 1.00 1.10 0.59

No. Samples, n

Mean, 0

Std. Dev., s

6

4.19

2.87

6

1.53

0.73

6

5.66

3.60

6

3.64

2.21

6

4.28

3.33

6

1.41

0.73

Summary of PUF Roller Transfer Efficiency Data From Application Days 1 and 3

No. Samples, n

Mean, 0

Std. Dev., s

4

5.63

2.33

4

1.92

0.55

4

7.55

2.70

4

4.76

1.73

4

5.91

2.80

4

1.79

0.56

Summary of PUF Roller Transfer Efficiency Data From Days 2 and 4

No. Samples, n

Mean, 0

Std. Dev., s

2

1.32

0.23

2

0.77

0.08

2

1.88

0.02

2

1.40

0.56

2

1.02

0.12

2

0.66

0.09

% Loss377 60 75 70 83 63

Summary of PUF Roller Transfer Efficiency Data From Day 1 of 1993 Vinyl Study

No. Samples, n

Mean, 0

Std. Dev., s

2

10.48

7.64

6

4.70

3.31

2

8.62

2.97

6

5.48

1.18

2

8.40

6.30

6

6.23

4.69

Summary of PUF Roller Transfer Efficiency Data From Day 2 of 1993 Vinyl Study

No. Samples, n

Mean, 0

Std. Dev., s

2

5.26

3.26

6

2.05

1.04

2

5.84

2.64

6

1.81

3.94

2

4.60

3.08

6

2.51

1.14

% Loss450 56 32 67 45 60

1 Transfer Efficiency, % = 100 × (transfer rate, ng/cm2

)/(mean surface loading, ng/cm2)

2 Fresh application of pesticide made on these days

3

(Difference between means of Days 1, 3 and Days 2 , 4/mean of Days 1, 3) × 100

4

(Difference between means of Day 1 and Day 2/mean of Day 1) × 100
15

Table 6. Comparison of Palm Transfer Rates of Chlorpyrifos, Pyrethrin I and

Piperonyl Butoxide from Day 3 of Experiment 6.2 Using Plush Carpet and

Experiment 7 Using Vinyl Sheeting

Chlorpyrifos Pyrethrin I Piperonyl Butoxide

Palm Treatment

ng/cm2

from

Vinyl

ng/cm2

from

Carpet

ng/cm2

from Vinyl

ng/cm2

from

Carpet

ng/cm2

from

Vinyl

ng/cm2

from

Carpet

Dry 67.1 9.1 4.3 1.3 36.1 10.0

Water Moistened 227.8 12.3 15.4 2.2 133.5 26.4

Saliva Moistened 227.9 11.3 13.1 1.4 120.2 16.6

Surface Loading 3391 3408 118 145 2074 3158
16

Table 7. Design for the Transfer Efficiency Test on New, Vinyl Sheet

Flooring (Task 7)

Test Day

Carpet

Section

Human Palm Press,1 by Palm Treatment Dry

PUF

Roller5

Deposition

Dry Coupons 2

WaterMoistened3SalivaMoistened4

Day 1: A61L72L 3L 1 1

3R 1R 2R 1 1

Day 2: A 2L 3L 1L 1 1

Day 3: B61R 2R 3R 1 1

3L 1L 2L 1 1

Day 4: B 2R 3R 1R 1 1

Field Samples 6 6 6 6 6

Field Blanks

(Day 0: A )

1L, 3R 2L, 1R 3L, 2R 2 0

Field Spikes

(Days 1 & 4)

2 2 2 2 2

Total Samples 10 10 10 10 8

1 One press of treated palm through template onto 3.5-cm × 3.5-cm square of treated

vinyl

2 Dry palm moistened with subject’s saliva

3 One pass over 3-foot strip with dry PUF roller

4 Palm dried after washing with soap and water

5 Dry palm moistened with water

6 Fresh treatment of this vinyl section on this day, at least four hours before palm

presses

7 Subject hand (e.g., 1L = left hand of Subject 1)
17

Table 8. Isopropanol Gauze Palm Wipe, PUF Ring, and Deposition Coupon Blanks

(μg/sample)

Blanks

Matrix Chlorpyrifos Pyrethrin I Piperonyl Butoxide

Solvent Blank (PUF/Coupon)

Solvent Blank (gauze wipes)

<1.0

<0.10

<0.63

<0.063

<1.1

<0.11

Lab Coupon Blank (dry)

Lab PUF Ring Blank (dry)

Lab Gauze Blank (dry)

<2.1

<1.0

<0.10

<2.1

<0.63

<0.63

<2.2

<1.0

<0.11

Field PUF Ring Blank (dry)

Day 0 (L)

Day 0 (R)

<1.0

<1.0

<0.63

<0.63

<1.1

<1.1

Field Blank for Gauze Wipe

Dry Palm - 1L

Dry Palm - 3R

Water-Wetted Palm - 2L

Water-Wetted Palm - 1R

Saliva-Wetted Palm - 3L

Saliva-Wetted Palm - 2R

<0.10

<0.10

<0.10

<0.10

<0.10

<0.10

<0.063

<0.063

<0.063

<0.063

<0.063

<0.063

<0.11

<0.11

<0.11

<0.11

<0.11

<0.11
18

Table 9. Recovery of Target Analytes from Matrix Spikes

Matrix/Wetting Agent

Type: Day Chlorpyrifos Pyrethrin I Piperonyl Butoxide

PUF Ring 110% 119% 140%

Deposition Coupon1

Lab

Field:Day 1

Field:Day 4

91%

75%

65%

106%

87%

57%

84%

90%

55%

Gauze2 (Dry)

Lab

Field:Day 1

Field:Day 4

91%

97%

97%

73%

132%

105%

90%

103%

97%

Gauze/Water

Field:Day 1

Field:Day 4

91%

84%

119%

92%

97%

84%

Gauze/Human Saliva

Field:Day 1

Field:Day 4

97%

91%

125%

99%

103%

90%

1 Each coupon was spiked with 410 μg chlorpyrifos, 40 μg pyrethrin I, and 412 μg piperonyl

butoxide

2 Wetted Sof-Wick®

 sponge pairs were moistened with 250 μL of the specified fluid. Each pair

was then spiked with 15 μg chlorpyrifos, 1.5 μg pyrethrin I, and 15 μg piperonyl butoxide.
19

Table 10. Comparison of Chlorpyrifos Transfer from New, Vinyl Sheet Flooring by Single Press of Human Palm (Dry and

Moist)

Deposition Dry Water Saliva

Block

Coupon

Amount

 μg

Surface

Loading

ng/cm2

Subject

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Subject 

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Subject

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Day 11

1L 317 5456 1L 6.7 84.1 2L 22 278.5 3L 5.9 74.7

1R 184 3167 3R 5.4 68.4 1R 26 329.1 2R 16 202.5

Day 2

2L 219 3769 2L 2.7 34.2 3L 5.0 63.3 1L 8.5 107.60

3R 221 3804 1R 3.6 45.6 2R 14 177.2 3R 10 126.6

Day 31

3L 173 2978 3L 7.0 88.6 1L 22 278.5 2L 26 329.1

Day 4

4R 19523356 2R 1.9 24.0 3R 4.3 54.4 1R 9.3 117.7

No. Samples, n

Mean, 0

Std. Dev., s

6

3775

895

6

57.5

26.8

6

196.8

117.8

6

159.7

93.1

1 Fresh pesticide application made on Days 1 and 3

2 Estimated amount is the difference between the field deposition coupon (inadvertently spiked with 410 μg chlorpyrifos) and field matrix spike

with 410 μg chlorpyrifos.
20

Table 11. Comparison of Pyrethrin I Transfer from New, Vinyl Sheet Flooring by Single Press of Human Palm (Dry

and Moist)

Deposition Dry Water Saliva

Block

Coupon

Amount

 μg

Surface

Loading

ng/cm2

Subject

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Subject 

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Subjec

t

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Day 11

1L 11 189.3 1L 0.50 6.33 2L 1.4 17.72 3L 0.46 5.82

1R 4.4 75.7 3R 0.42 5.32 1R 1.6 20.25 2R 0.88 11.14

Day 2

2L

3.0 51.6 2L 0.15 1.90 3L 0.26 3.29 1L 0.51 6.46

Day 31

 3R 8.1 139.4 1R 0.19 2.41 2R 0.94 11.90 3R 0.57 7.22

3L 5.6 96.4 3L 0.49 6.20 1L 1.5 18.99 2L 1.5 18.99

Day 4

4R 5.0286.1 2R 0.085 1.08 3R 0.28 3.54 1R 0.57 7.22

No. Samples, n

Mean, 0

Std. Dev. s

6

106.4

49.8

6

3.87

2.34

6

12.62

7.68

6

9.47

5.02

1 Fresh pesticide application made on Days 1 and 3

2 Estimated amount is the difference between the field deposition coupon (inadvertently spiked with 40μg pyrethrum I) and field matrix spike

with 40 μg pyrethrum I. 
21

Table 12. Comparison of Piperonyl Butoxide Transfer from New, Vinyl Sheet Flooring by Single Press of Human Palm

(Dry and Moist)

Deposition Dry Water Saliva

Block

Coupon

Amount

 μg

Surface

Loading

ng/cm2

Subject

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Subject 

Palm

Palm Wipe

Amount

μg

Transfer

Rate

ng/cm2

Subject

Palm

Palm

Wipe

Amount

μg

Transfer

Rate

ng/cm

Day 11

1L 203 3494 1L 3.6 45.6 2L 11 139 3L 3.6 45.6

1R 109 1876 3R 3.2 40.5 1R 14 177 2R 9.3 118

Day 2

2L 119 2048 2L 1.4 17.7 3L 2.4 30.4 1L 4.6 58.2

Day 31

3R 145 2496 1R 1.8 22.8 2R 8.1 102 3R 5.0 63.3

3L 96 1652 3L 3.9 49.4 1L 13 164 2L 14 177

Day 4

 4R 10021721 2R 0.91 11.5 3R 2.2 27.8 1R 4.8 60.8

No. Samples, n

Mean, 0

Std. Dev. s

6

2215

695

6

31.2

15.9

6

107.0

65.5

6

87.1

50.7

1 Fresh pesticide application made on Days 1 and 3

2 Estimated amount is the difference between the field deposition coupon (inadvertently spiked with 412 μg piperonyl butoxide) and field matrix

spike with 412 μg piperonyl butoxide. 
22

Table 13. Transfer Amount of Pesticides from Treated, New, Vinyl Sheet Flooring onto PUF Roller and Dry Palm After

Single Press

Chlorpyrifos Pyrethrin I

Piperonyl

Butoxide

Day

Deposition

Coupon

μg

PUF

 μg

Dry

Palm

μg

Deposition

Coupon

μg

PUF

μg

Dry Palm

μg

Deposition

Coupon

μg

PUF

μg

Dry Palm

μg

1L

1R

317

184

70

203

6.7

5.4

11

4.4

3.2

7.8

0.50

0.42

203

109

39

146

3.6

3.2

2L 219 33 2.7 3.0 1.4 0.15 119 16 1.4

3R

3L

221

173

127

180

3.6

7.0

8.1

5.6

4.9

6.5

0.19

0.49

145

96

71

105

1.8

3.9

4R 195 35 1.9 5.0 1.4 0.08 100 15 0.91
23

23

Table 14. Transfer Rate of Pesticides from Treated, New, Vinyl Sheet Flooring onto PUF Roller and Dry Palm After

Single Press

Chlorpyrifos Pyrethrin I

Piperonyl

Butoxide

Day

Deposition

Coupon

ng/cm2

PUF

ng/cm2

Dry 

Palm

ng/cm2

Deposition

Coupon

ng/cm2

PUF

ng/cm2

Dry 

Palm

ng/cm2

Deposition

Coupon

ng/cm2

PUF

ng/cm2

Dry

 Palm

ng/cm2

1L

1R

5456

3167

100.4

291.3

84.1

68.4

189.4

75.7

4.59

11.2

6.3

5.3

3494

1876

56.0

209.5

45.6

40.5

2L 3769 47.4 34.2 51.6 2.01 1.9 2048 23.0 17.7

3R

3L

3804

2978

182.3

258.3

45.6

88.6

139.4

96.4

7.03

9.33

2.4

6.2

2496

1652

101.9

150.7

22.8

49.4

4R 3356 50.2 24.0 86.1 2.01 1.1 1721 21.5 11.5