United States Prevention, Pesticides EPA712-C-96-209
Environmental Protection and Toxic Substances February 1996
Agency (7101)
&EPA Occupational and
Residential Exposure
Test Guidelines
OPPTS 875.1200
Dermal Exposure—
ndoor
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INTRODUCTION
This guideline is one of a series of test guidelines that have been
developed by the Office of Prevention, Pesticides and Toxic Substances,
United States Environmental Protection Agency for use in the testing of
pesticides and toxic substances, and the development of test data that must
be submitted to the Agency for review under Federal regulations.
The Office of Prevention, Pesticides and Toxic Substances (OPPTS)
has developed this guideline through a process of harmonization that
blended the testing guidance and requirements that existed in the Office
of Pollution Prevention and Toxics (OPPT) and appeared in Title 40,
Chapter I, Subchapter R of the Code of Federal Regulations (CFR), the
Office of Pesticide Programs (OPP) which appeared in publications of the
National Technical Information Service (NTIS) and the guidelines pub-
lished by the Organization for Economic Cooperation and Development
(OECD).
The purpose of harmonizing these guidelines into a single set of
OPPTS guidelines is to minimize variations among the testing procedures
that must be performed to meet the data requirements of the U. S. Environ-
mental Protection Agency under the Toxic Substances Control Act (15
U.S.C. 2601) and the Federal Insecticide, Fungicide and Rodenticide Act
(7U.S.C. I36,etseq.).
Final Guideline Release: This guideline is available from the U.S.
Government Printing Office, Washington, DC 20402 on The Federal Bul-
letin Board. By modem dial 202-512-1387, telnet and ftp:
fedbbs.access.gpo.gov (IP 162.140.64.19), internet: http://
fedbbs.access.gpo.gov, or call 202-512-0132 for disks or paper copies.
This guideline is also available electronically in ASCII and PDF (portable
document format) from the EPA Public Access Gopher (gopher.epa.gov)
under the heading "Environmental Test Methods and Guidelines."
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OPPTS 875.1200 Dermal exposure—indoor.
(a) Scope—(1) Applicability. This guideline is intended to meet test-
ing requirements of the Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) (7 U.S.C. 136, et seq.\
(2) Background. The source material used in developing this har-
monized OPPTS test guideline are OPP guidelines 230 and 233. This
guideline should be used with OPPTS 875.1000.
(b) Estimation of dermal exposure by passive dosimetry—(1) Con-
struction of dermal exposure pads and storage envelopes of exposed
pads—(i) Dermal exposure pads for sprays. Pads to be used for estimat-
ing dermal exposure to sprays are to be constructed from papermaking
pulp or a similar material, referred to as a-cellulose, approximately 1 mm
thick. A good grade of a-cellulose will absorb a considerable amount of
spray without disintegrating. Further, it should not typically require
preextraction to remove substances that interfere with residue analysis.
This should be determined before using such pads in exposure tests.
Acetanier P-FA, produced by ITT Rayonier, Inc., Chemical Cellulose Sales
Department, 1177 Summer St., Stamford, CT 06904, has been found to
be satisfactory for this use. It is available only in 500 Ib bales, but 4 Ib
samples of 10 inch square sheets are available at no charge (shipping not
included) if an investigator wishes to compare it to other potential dermal
dosimeter materials before choosing an appropriate pad material. Another
material, which is satisfactory and more readily available in small lots,
is preparative chromatography paper (17 Chrom) available in sheets from
Whatman, Inc., 9 Bridewell Place, Clifton, NJ 07014. The large sheets
available form the manufacturer are cut into approximately 4 inch
(10.2 cm) squares which are stapled to a protective backing of glassine
paper or aluminum foil. Glassine powder-weighing paper precut into
4 inch (10.2 cm) squares is produced by Schleicher and Schuell, Inc., and
is available through most laboratory supply companies. The glassine paper
or aluminum foil backing prevents contamination of the exposure pad by
material deposited on the subject's clothing during a previous spraying.
(ii) Dermal exposure pads for dry residues. Pads to be used for
estimating dermal exposure to dust formulations, dried residues, and to
dust from granular formulations, are to be constructed from layers of sur-
gical gauze. A piece of heavy filter paper backing approximately 4 inch
(10.2 cm) square is overlayed with approximately 32 plies of surgical
gauze and the components are bound together with masking tape along
all four edges. The finished pad should be bound so that an area of gauze
at least 2.5 inch (6.4 cm) square is left exposed. The gauze must be
checked for material that would interfere with analysis and be preextracted
if necessary.
(iii) Storage envelopes to contain exposed pads. If exposed pads
are to be stored prior to extraction, envelopes cut from heavy filter paper
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my be used. The same white crepe filter paper that is used for backing
the dust exposure pads is suitable for this use. It is also necessary to check
the envelope for material that will interfere with analysis, since that portion
of the envelope that will be in contact with a stored exposure part must
also be extracted to obtain any residues that may have been transferred
from the pad. A 5x10 inch (12.6x25.2 cm) rectangle cut from the large
sheet of filter paper is folded once across the long dimension so that ap-
proximately 0.75 inch (2.2 cm) of the lower portion projects above the
upper portion. This projection provides a convenient space to record the
sample number of the exposed pad contained in the envelope. The filter
paper envelopes are contained in individual unwaxed sandwich bags ap-
proximately 6.5x8x1 inch (16.5x20.3x2.5 cm). The sandwich bags keep
the exposed pads within the protective envelopes and help protect against
contamination.
(2) Preparation of hand rinses, (i) Hand rinses are prepared by plac-
ing solvent in freezer bags or other plastic bags strong enough to withstand
vigorous shaking. A satisfactory bag is designed to contain 0.5 gal
(1.9 L) of frozen food. Bags less that 1 mil (0.025 mm) inch thickness
will puncture too easily to be useful. Use the heaviest available material
that is still pliable enough to be wrapped in a tight seal around the wrist.
(ii) During preliminary studies, plastic bags must be shaken with the
solvent to be used for field studies to ensure that material which may
interfere with analysis is not present. This procedure must be followed
regardless of the type of bag used.
(iii) Ethanol (95 percent) has been found to be satisfactory for the
removal of most pesticide residues without undue damage to the skin. If
the material under study is unstable or insoluble in ethanol, it may be
necessary to remove residues using a detergent solution rinse followed by
partition of the residue into a suitable solvent for analysis.
(iv) Alcohol hand rinses are prepared by placing 200 mL of 95 per-
cent ethanol in a freezer bag, performing the hand rinse, placing the bag
in a wide-mouth 1-pt Mason jar, twisting (or zipping) the top of the bag
shut to contain the solvent, and sealing the jar with a lid and a ring. A
sheet of aluminum foil inside the lid will help to prevent contamination
of the sample. Record the sample number of the hand rinse on a piece
of masking tape on the outside of the lid. The sample bottles and caps
should be labeled to avoid mix-ups. Stainless steel or other appropriate
containers may be substituted for Mason jars.
(3) Laboratory studies necessary before field studies are initiated.
The total recovery from field-fortified samples must be at least 50 percent.
Field-fortified samples should reflect the total sample monitoring and anal-
ysis process. Applicable good laboratory practices must be followed at
all times. Refer to 40 CFR 160.
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(i) Analytical procedure. The specific analytical procedure to be
used will depend on the material being studied. The procedure chosen must
be capable of quantitative detection of residues on exposure pads at a level
of 1 (ig/cm2 (less if the dermal toxicity of the material under study war-
rants a greater sensitivity).
(ii) Stability of the compound of interest on damp stored pads.
(A) Two options will be offered under paragraph (b)(4)(ii) of this guideline
on treatment of exposed pads used with sprays prior to extraction. If the
investigator elects to store exposed pads pending extraction, a study must
be documented for the stability of the material on moist exposure pads.
(B) Exposure pads are to be fortified with a pesticide product diluted
to use concentration, at approximately the levels that are expected to im-
pinge on pads during field studies. The same formulated pesticide product
which will be used in the field study must be used as spray material for
pad fortification. The pads and their protective envelopes are to be ex-
tracted and analyzed by the methods that will be employed for field stud-
ies. The time periods for storage of fortified pads should be chosen so
that the longest corresponds to the longest projected storage period for
field samples. Construction of a decay curve will allow extrapolation of
residue levels found in field samples. Results from this study can also
be used to determine the length of storage which will be acceptable for
the pesticide formulation to be monitored in the field study.
(iii) Efficiency of extraction. (A) The method chosen by the inves-
tigator to extract residues from exposure media must be studied efficiency
of extraction and this study must also be documented. The appropriate
type of exposure media must be fortified with simulated spray solution
prepared using the same formulation that will be studied in the field and
at approximately the same levels as are expected for field samples. The
mean plus or minus the standard deviation for recovery must be deter-
mined. If the lower limit of the 95 percent confidence interval is less that
70 percent, the extraction procedure is unsatisfactory unless approved by
the Agency prior to commencing the study. At a minimum, seven deter-
minations should be made to calculate the mean and standard deviation
for recovery for each fortification level tested. Studies should always be
designed so that extraction efficiencies are the highest possible.
(B) If hand rinses are to be carried out using a particular solvent
with subsequent partition into a second solvent for analysis, a study similar
to that described under paragraph (b)(3)(iii) of this guideline are to be
carried out to determine the efficiency of extraction. The same criteria
for acceptability also applies to hand rinse extractions.
(iv) Estimation of expected stability during the monitoring study.
(A) If the stability of the material of interest is unknown, or if the material
is volatile or subject to degradation, investigators must undertake and doc-
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ument a study to ascertain loss while pads are worn to determine the length
of the monitoring period and to allow for correction for residues lost from
collection devices during the monitoring period. Because no standard pro-
cedure has been developed for this type of study, it is left to the investiga-
tors to develop their own.
(B) It is recommended that collection devices be fortified with simu-
lated spray solution or dust, depending on the material being studied, at
approximately the same levels expected to occur during field studies.
These dosimeters should be exposed to weather condition similar to those
expected during field studies and for the same period of time as will be
employed in the field.
(4) Field operations—(i) Attachment of exposure pads. (A) Ac-
cording to the exposure situation, pads are to be attached to collect resi-
dues representative of those impinging on all regions of the body. Nor-
mally, a complete set of pads for each exposure period will consist of
10 to 12 pads (see paragraph (b)(3) of this guideline).
(B) The pads are attached to the outside of a worker's clothing or
skin at the following locations: Top of the shoulders, in back of the neck
just below the lower edge of the collar, on the upper chest near the jugular
notch, in back of the forearms, and in front of the thighs and lower legs.
If workers are engaged in some activity that is likely to result in extraor-
dinary exposure to regions of the body that are not well represented by
the usual pad locations, extra pads must be included to assess such expo-
sure.
(C) If the determination of actual penetration of work clothing is de-
sired in the field study, additional pads can be attached under the worker's
outer garments. Since workers often wear upper and lower outer garments
made from different types of cloth, pads should also be attached under
both garments, particularly in regions expected to receive maximum expo-
sure. Care must be taken to ensure that any pads under clothing are near,
but not covered by, pads on the outside of the clothing.
(D) If the proposed label specifies that the pesticide can only be used
by workers using protective garments, place the pads where it is possible
to assess exposure to unprotected regions. For example, if the workers
are wearing full protective suits, pads would be needed on the outside
of the garments at the back, chest, and shoulders, to assess facial, head,
and neck exposure. Additional pads will be necessary under the protective
suit at all previously specified locations to assess penetration. Inside pads
must be centered under seams as well as under unseamed material, since
seams are often areas of maximum penetration. Registrants are encouraged
to discuss exposure studies involving protective clothing with Agency per-
sonnel when developing a protocol and before submittal for approval.
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(E) Pads may be attached to the skin or clothing by using strips of
masking tape along two edges of a pad. Some investigators have utilized
specially designed harnesses or lightweight vests fitted with open-fronted
pockets to hold the shoulder, chest, and back pads. Others have simply
attached the pads on clothing with safety pins. These alternative attach-
ment methods and others have been used successfully and are acceptable.
(ii) Removal and handling of exposed pads. The procedure for han-
dling exposed pads will depend on the stability of the material being stud-
ied. If the laboratory study described under paragraph (b)(3)(ii) of this
guideline indicates that the material is stable on moist exposure pads, the
method under paragraph (b)(4)(ii)(A) of this guideline may be used. This
method is advantageous since it requires less time-consuming manipulation
of the exposed pads in the field. If the material is found to be unstable,
or if the investigator elects not to perform the stability testing with moist
pads, the method under paragraph (b)(4)(ii)(B) of this guideline are to be
employed. The latter method may also be employed by choice.
(A) Stable residues. Remove the tape used to attach the pad to the
test subject and also remove the protective backing from the pad. Slide
the prelabeled protective envelope just far enough out of the sandwich
bag to insert the pad, and carefully move the envelope back into the plastic
bag. Staple all bags containing exposed pads from one exposure of a single
test subject together without puncturing the area of the bag containing the
samples and store in a chest containing ice or an appropriate frozen plastic-
encapsulated gel. Refrigerate the bags until reaching the laboratory.
(B) Unstable residues. Remove the tape used to attach the pad to
the test subject. Place a template of convenient size (25 cm2 has been
employed with success) in the center of the pad and trim away the excess
material around the template. Discard the protective backing and place the
sample obtained from the center of the pad in a wide-mouth jar or other
appropriate container filled with a convenient volume of a suitable solvent.
Store this sample in the same manner as the pads with stable residues.
(iii) Hand rinses. A double hand rinse must be performed on each
hand. These rinses must be done even on workers who wore protective
gloves. A plastic bag containing an appropriate solvent is removed from
its Mason jar (or other container) and is tightly applied just below the
wrist bone. The hand is shaken vigorously in the solvent, and allowed
to drain into the bag for a few seconds, after which the bag is returned
to its container. This procedure is repeated on the same hand with a fresh
bag of solvent before performing the process on the other hand. These
rinses should also be stored under the conditions used for exposed pads
until reaching the laboratory.
(iv) Field-fortified samples and blanks. (A) Inclusion of field-for-
tified samples in a study is vital because it will allow data to be corrected
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for any residue losses that may occur during the exposure period, during
storage in the field, and during transportation to the laboratory. The need
for a study of the stability of residues on damp stored pads is eliminated
if field-fortified samples are extracted on the same day as are the samples
which have been collected.
(B) Because a standard procedure to assess losses from field-fortified
samples has not been developed, it is left to the investigator to propose
such a procedure. However, the Agency recommends the following as a
guide:
(7) Pads should be fortified at approximately the levels expected for
actual exposure samples. The fortified pads should be exposed to the
weather concurrently with the pads being worn by the workers. A member
of the monitoring team who is careful to position him or herself where
inadvertent exposure cannot occur may wear the fortified pads, or they
may be placed in a fixed location that is upwind and a sufficient distance
from the application site to avoid contamination. However, investigators
are cautioned that upwind locations can quickly become downwind loca-
tions, and such occurrences will ruin a set of fortified samples.
(2) There should be at least one field-fortified sample per worker per
monitoring period for each fortification level. These samples should be
stored and analyzed along with the exposure samples. Field blanks of ex-
posure collection media such as pads are also required in order to account
for any possible contamination which may occur while collecting, trans-
porting, or handling field samples prior to extraction in the laboratory.
Field blanks should be handled in the same manner as exposed pads.
(v) Field data collection. The type of field data that must be reported
will vary with the operation being studied. A set of data must be compiled
for each set of exposure pads and hand rinses. These data must be indexed
so that they can easily be related to any particular exposure value. Two
examples of the type of data needed in a particular exposure situation are
presented as a general guide.
(A) Agricultural applications, yards, and gardens (7) Pesticide
identification—chemical name, formulation, EPA registration number, lot
number, and type of concentrate container.
(2) Investigator's name.
(3) Description of the area—crop, plot size, and row spacing.
(4) Application data—rate, tank capacity, type of carrier, final mix
concentration, total pounds applied or mixed.
(5) Equipment data—type, model.
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(6) Weather data — relative humidity, wind speed, wind direction, and
temperature.
(7) Work activity monitored.
(8) Location of exposure pads on the subject and sample numbers
corresponding to these pads.
(9) Exposure observations — direction of travel of applicator in rela-
tion to wind direction, and any special situation observed that might alter
normal exposure, such as splashing concentrate directly on a particular
pad while filling tank.
(Iff) Exposure time — presented in such a way that total exposure can
be calculated per amount of pesticide (or other chemical) handled for the
time interval of each work activity.
(B) Structural pest control, greenhouse, indoor residential appli-
cations (7) Pesticide identification — chemical name, formulation, EPA
registration number, lot number, and type of concentrate container.
(2) Investigator's name.
(3) Description of area — linear feet of baseboard treated, size of
rooms.
(4) Indoor environmental conditions — ventilation, air exchange rate,
if known.
(5) Application data — rate, tank capacity, type of carrier, final mix
concentration, total pounds applied or mixed.
(6) Equipment data — type, model.
(7) Weather data — relative humidity and temperature.
Work activity monitored.
Location of pads on the subject and sample numbers correspond-
ing to these pads.
(Iff) Exposure observations — special situations observed that might
alter normal exposure, such as adjusting nozzle or rinsing hands after fill-
ing tank.
(11} Exposure time — presented in such a way that total exposure can
be calculated per amount of pesticide (or other chemical) handled for the
time interval of each work activity.
(5) Laboratory operations subsequent to exposure. As soon as the
investigator returns to the laboratory from the field, all samples held in
ice chests must be stored in a freezer pending further treatment. A sample
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history sheet is to be prepared to document laboratory operations. A con-
venient sheet of this type contains columns labeled: Sample number, date
sample was collected, date of extraction, date of analysis, and the names
of the responsible individuals for each laboratory procedure. The lower
portion of the sheet contains spaces for recording the conditions of storage
for pads and extracts, the extraction procedure employed, and the analyt-
ical procedure used. A suggested form for a sample history sheet is pro-
vided.
(i) Extraction of residues from exposed pads. (A) If exposed pads
are returned to the laboratory intact, portions of the pads along with their
protective envelopes are cut out as described under paragraph (b)(4)(ii)
of this guideline. These samples are extracted according to the procedure
that was determined as appropriate by earlier laboratory studies under para-
graph (b)(3)(iii) of this guideline. If portions of the pad were cut out and
placed in solvent in the field, no further manipulation is necessary before
extraction. The data and method of extraction are to be entered on the
sample history sheet and the extracts either analyzed immediately or stored
under appropriate conditions (under paragraph (b)(3)(iv) of this guideline)
for later analysis. If stored, the method of storage must be specified on
the sample history sheet.
(B) To reduce laboratory work, pads from opposite sides of the body
can be combined prior to extraction. However, if residue values from par-
ticular pads are needed for calculations, these pads must be extracted sepa-
rately. Examples of pads that may not be combined are those from the
chest and back and exterior pads adjacent to pads under clothing, which
will be used to estimate penetration.
(ii) Hand rinses. After returning to the laboratory, both right hand
rinses are combined into one sample. The same is true for both left hand
rinses. Entries are necessary on the sample history sheet for date and meth-
od of extraction. If the samples are to be stored, then the method of storage
must be noted.
(iii) Analysis of samples. All samples must be analyzed by the meth-
ods meeting the criteria specified under paragraph (b)(3)(i) of this guide-
line. The date and method of analysis are to be entered on the sample
history sheet. Fortified substrates should be analyzed along with exposure
samples to determine whether total recovery criteria have been met.
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DATA REPORT FORM
Exposure Sample History
Sample Series
Sample num-
ber
Date
Col-
lected
By
Date
Ex-
tracted
By
Date
Ana-
lyzed
By
Preextraction storage:
Extraction procedures:
Analysis:
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(6) Presentation of results—(i) Standard body surface areas.
(Refer to paragraph (b)(6)(i) of this guideline.) Calculation of total dermal
exposure will be performed by the Agency and are therefore not required
of the registrant. For the calculation of adult dermal exposures, the body
surface areas given in the following Table 1. will be employed by the
Agency:
Table 1. Body Surface Areas for Calculation of Adult Dermal Exposures
Region of the Body
Head (includes face)
Face
Back of Neck
Front of Neck
Chest/Stomach
Back
Upper Arms
Forearms
Hands
Thighs
Lower Legs
Feet
Surface Area of Region
(cm2)
1,300
650
110
150
3,550
3,550
2,910
1,210
820
3,820
2,380
1.310
(ii) Information for dermal exposure calculations.—(A) The der-
mal exposure for any particular body area will be the product of the body
surface area given above and the appropriate residue level expressed as
micrograms of residue per square centimeter of exposure pad
(|j,g/cm2/pad). Information must be reported so that exposure can be cal-
culated as a function of time engaged in the work activity and as a function
of the amount of chemical handled in the work activity. In some cases,
more than one pad is representative of the area exposed. For these cases,
the mean of residues found on the appropriate pads will be used. If any
pad is found to contain a level of residue that is below the limit of quan-
tification of the procedures employed, the level of residue on the pad will
be considered to be half of this limit. The body areas of interest are related
to the appropriate exposure pads in the following Table 2. Refer to para-
graph (b)(5)(i)(B) for examples of which pads should not be combined
for analysis.
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Table 2. Locations of Dermal Exposure Pads That Represent Different Regions of the Body
Body area of concern
Exposure pads representative of the body area
Totally unprotected head1
Face
Neck
Upper arms
Forearms
Hands
Chest .
Back ...
Thighs
Calves
Feet ....
Shoulder, chest, and back2
Chest
Chest and back
Shoulder and forearm/ upper arm
Forearm
Total of residues in the hand rinses or monitoring glovesis used with-
out regard for surface area
Chest
Back
Thigh
Shins
If necessary, total of residues in socks can be used without regard for
surface area.
1 Includes face.
2 Exposure to the head may be estimated by using the mean of the shoulder, back, and chest patch-
es, or by using a head patch.
(B) Final results must be reported in the text of the report submitted
to the Agency as the mean of the exposure per square centimeter of the
collection pad for each region of the body. These results must be corrected
for total recovery. The number of separate exposures giving rise to each
mean and the rate of the exposure must be specified. The exposure per
square centimeter of the collection pad for each region of the body for
each separate exposure must also be submitted to the Agency.
(C) Final results must include pertinent field data such as type of
application equipment, formulation, tank mix, application rate, pounds of
active ingredient handled, crop, and range of weather conditions. All as-
sumptions used in calculations must be included. Refer to OPPTS
875.1600 for complete instructions for data reporting requirements.
(7) Alternate methodology for the measurement of hand exposure.
(i) If the investigator finds that the previously described rinsing procedure
is not appropriate in a particular situation for monitoring exposure to the
hands, the use of absorbent gloves is acceptable. The use of gloves will
require that the studies described under paragraph (b)(3) of this guideline
to determine stability and extractability of residues performed prior to the
field study.
(ii) Lightweight absorbent gloves provide several advantages over
rinsing for the assessment of hand exposure. They can be changed very
quickly, trap toxicants that normally would be absorbed during the expo-
sure period, and can be used to collect residues that are insoluble in, or
are degraded by, water or ethanol. The use of gloves may also have certain
disadvantages. Gloves may absorb more material than would be retained
by the skin, thus overestimating hand exposure. Gloves often contain for-
eign materials that may interfere with low level analysis. This can be re-
duced by preextraction of gloves with an appropriate solvent.
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(iii) Two types of lightweight absorbent gloves have proven useful
for monitoring had exposure. One is a white cotton "pallbearer's" glove
and the other is a white nylon glove that is often used by handlers for
fruit packing.
(iv) Exposed gloves should be processed in the same manner as ex-
posed dermal pads. In the field, each pair of exposed gloves may either
be placed directly into a container of solvent, or into a protective envelope
inside an unwaxed sandwich bag. Upon returning to the laboratory, both
gloves in solvent or both gloves plus their protective envelope are ex-
tracted by an appropriate method.
(c) Indoor sites. For the purpose of these guidelines, indoor sites
include, but not be limited to: Homes and apartments,greenhouses, barns
and other farm buildings, commercial buildings and manufacturing facili-
ties, restaurants and food handling and processing facilities, fumigation
facilities, warehouses, railroad boxcars, schools, hospitals and other health
care facilities, and mushroom houses.
(d) Postapplication measurements. Postapplication measurements
will be required only on a case-by-case basis depending on the type of
pesticide product and its use.
(e) Number of replicates—dermal exposure. For exposure during
application, a minimum of five replicates each at a minimum of three rep-
resentative indoor sites are to be employed. It is recommended that as
many individuals as practicable be monitored.
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