United States
Environmental Protection
Agency
Water Engineering
Research Laboratory
Cincinnati OH 45268
Research and Development
EPA/600/S2-88/033 Sept. 1988
v°/EPA Project Summary
Pesticide Exposure to Florida
Greenhouse Applicators
H. N. Nigg, J. H. Stamper, and W. D. Mahon
The exposure of pesticide applicators
in a commercial greenhouse facility was
assessed. Data were collected primari-
ly from five handgunners and a tractor
driver. A drencher was also monitored on
one occasion, as was one of the hand-
gunners when acting as an assistant to
another handgunner. The chemicals ap-
plied were fluvalinate, chlorpyrlfos,
ethazol, dlcofol, captan, and chloro-
halonil. Potential exposure was ass-
essed with exposure pads placed out-
side all clothing of the applicator. Hand-
washes and air samples, as well as pre-
and post-exposure tank mixture
samples, were also collected. Pesticide
penetration was measured with ex-
posure pads placed inside protective
clothing.
It was found useful in this study to nor-
malize all exposure assessments for
spray rate. This done, handgunner ex-
posure increased with increasing
fineness of the spray leaving the nozzle;
the tractor driver was much less exposed
than the handgunners. Ethazol pene-
trated Tyvek™* more than any other
compound tested.
This Project Summary was developed
by EPA's Water Engineering Research
Laboratory, Cincinnati, OH, to announce
key findings of the research project that
is fully documented in a separate report
of the same title (see Project Report
ordering information at back).
Introduction
The exposure of greenhouse applicators
is of current regulatory interest to the U.S.
Environmental Protection Agency. The U.S.
EPA is specifically faced with the task of (1)
assessing the potential pesticide exposure
'Mention of trade names or commercial products does
not constitute endorsement or recommendation for use.
of greenhouse applicators and (2) sug-
gesting protective clothing that is both ef-
fective and comfortable. This study is a first
step toward providing the data necessary
for evaluations by the U.S. Environmental
Protection Agency, the greenhouse in-
dustry, and pesticide manufacturers.
This study was conducted in 1985-86 at
a commercial greenhouse facility in west-
central Florida. The facility, devoted primari-
ly to growing chrysanthemums and African
violets, occupied three locations: at Parrish,
FL, and Palma Sola, FL, where handgun-
ners were monitored, and at Cortez, FL,
where a tractor driver was monitored.
Data were collected from five handgun-
ners who sprayed with either a fine spray,
a coarse spray, or pulse fogging device; the
tractor driver who pulled either a boom
sprayer or a span sprayer; a drencher; and
one of the handgunners when acting as an
assistant to a fine spray handgunner. The
chemicals applied were fluvalinate, chlor-
pyrifos, ethazol, dicofol, captan, and
chlorothalonil.
The questions this study addressed were
the following: (1) What is the potential for
dermal exposure to greenhouse pesticide
applicators? In other words, at what rate
would pesticide accumulate on the body of
an applicator, unprotected by clothing of
any kind? We term this "estimated total
body accumulation rate" (ETBAR) and
measure it in jig/hr. Also, does the ETBAR
depend upon the rate of pesticide leaving
the spray nozzle, the kind of pesticide ap-
plied, the method of application (including
type of nozzle), and/or the individual work
habits of the applicator? (2) How is the ET-
BAR distributed over the anatomy of the ap-
plicator and upon what parameters does
this distribution depend? (3) What is the ac-
cumulation rate of pesticide on the hands
of applicators? Is there a relationship be-
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tween worker hand preference (right or left)
and exposure to the right and left hands?
Does hand exposure depend upon the
pesticide effluent rate, compound applied,
application method, and/or individual work
habits? (4) What is the atmospheric con-
tamination of the pesticide in the breathing
zone of the worker as he applies the com-
pound? Does it depend upon the com-
pound, its effluent rate, or the application
method? (5) What is the penetration of
pesticide through the various types of pro-
tective clothing worn by applicators? Does
penetration depend upon the compound?
(6) How do samples of the spray mixture,
taken pre-.and post-application, compare
in pesticide concentration with that pre-
sumed to exist in the tank based on the
mixture recipe and an assumption of
thorough mixing?
The complete report addresses all of the
questions. This summary addresses the
most salient of them.
Procedure
Seven subjects were chosen for this
study on the basis of their willingness to
participate and the frequency with which
they applied compounds our laboratory was
capable of analyzing. They were instructed
to change no aspect of their normal ap-
plication routine and to wear only their
usual protective clothing. Four subjects
were male, three were female, and they
ranged in age from 23 to 44 years. Their
heights and weights were recorded, from
which their total body surface areas were
estimated. The hand preference of each
was recorded.
Four of the workers normally sprayed
with a Cornel™ handgun equipped with a
6-nozzle head and attached with a long
hose to a Myers Du-AII Spray Pump™ and
an open, 60-gal, cylindrical tank. The spray
mixture, sometimes containing several
pesticide, fungicide, fertilizer, etc. com-
pounds, was discharged from the nozzles
as a fine, nearly misty, spray. These workers
usually sprayed in completely enclosed
greenhouses. They usually wore hooded
coveralls, gloves, boots, goggles, an apron,
and a respirator. Coveralls and hoods were
made from Dupont Tyvek™ and covered
all of the body surface except the face,
hands, and feet. Both coveralls and hoods
were disposable and changed between ap-
plications. Gloves, extending to mid-
forearm; boots, extending to mid-calf; and
bibbed aprons, extending from mid-chest
(or waist, if the bib was not raised) to the
ankle, were all made of butyl rubber. Ends
of the gloves were-not sealed. Goggles
covered the eyes; respirators covered the
nose and mouth. During pulse fogging, the
respirator was replaced by a canister chin-
style gas mask.
Another worker sprayed using an en-
closed, 300-gal tank with a handgun,
equipped with a single adjustable nozzle
set to provide a coarser spray. He usually
applied in an open-sided structure with a
translucent roof. His usual protective
clothing consisted only of an apron and
boots.
The sixth subject drove a tractor that
usually pulled a boom sprayer with an
enclosed 300-gal tank; however, for several
sampling periods he pulled a span sprayer.
He applied in an open-sided structure
covered on top with Siran™ a fine net-like
fabric used to attenuate sunlight intensity
in an otherwise completely open environ-
ment. He wore no protective clothing but
did use a respirator.
One exposure was taken from the
seventh subject as she drenched. Dren-
ching was done with a nozzle that gave a
low pressure, coarse spray pattern not
unlike what an ordinary sprinkling can
would provide. It was done in an entirely
enclosed greenhouse. She wore gloves,
boots, an apron, and a respirator.
Pulse fogging was occasionally practiced
by the fine spray handgunners in their
enclosed greenhouses. The pulse fogging
device (Dramm International Inc.
Pulsfog™, Style K-6005) had an enclosed,
8-gal tank and produced a misty (droplet
size advertized at 0.03 mm) spray from a
single nozzle.
Applicators mixed and loaded their own
tanks.
Potential dermal and respiratory ex-
posure was estimated according to the pro-
cedure described by Durham and Wolfe
(Bull. Wld. Hlth. Org. 26:75-91, 1962). Ex-
posure pads were placed on the subjects
as follows: the middle of the back, the
chest, the top of each shoulder, each
forearm, each thigh, and each shin. These
pads were entirely exposed, not covered by
protective gear of any kind. If an apron or
boot covered any of the above sites, pads
were placed on the outside of the apron or
boot at the same level as described above.
Left and right pairs of outside pads
(shoulders, forearms, thighs, and shins)
were combined for extraction and analysis.
Timed exposure periods were at the con-
venience of the subject but generally lasted
about 30 min. The analytical results for
pesticide compound, uncorrected for
recovery, divided by the pad area (one or
two pads) and exposure time, give the pad
fluxes. The ETBAR was calculated from the
outside pad fluxes as follows. Estimated
fractional body surface areas were allottee
to the head and neck, front torso, back tor-
so, arms, upper legs, and lower legs using
the proportions proposed by U.S. En-
vironmental Protection Agency, which are
sex-specific. Accumulation rates to the
arms, for example, are the product of the
estimated total body surface area, the arms
fraction (14.1% male, 14.0% female), and
the outside forearm pad flux. In the same
way, upper leg accumulation rates were
estimated from thigh pad fluxes, lower leg
rates from outside shin pad fluxes, back tor-
so rates from outside back pad fluxes, and
front torso rates from outside chest pad
fluxes. The head-neck accumulation rate
was similarly derived, with the flux
estimated from the average of the outside
chest, the outside back, and twice the out-
side shoulder fluxes. These various ac-
cumulation rates were then summed to ob-
tain the ETBAR. Handwash accumulation
rates were included only if the subject wore
no hand protection. The hands' contribu-
tion can then be regarded as truly exterior
and, therefore, on the same footing as out-
side pads; otherwise, handwashes are
omitted from the ETBAR. As a practical
matter, ETBAR's were not much influenced
by the inclusion or exclusion of hand-
washes. The atmospheric pesticide con-
tamination is given and is based upon a 3
L/min intake of air by the personal air
sampler. This air sampling device is de-
signed to collect primarily vapor and does
not discriminate among particle sizes. Tank
mixture samples were taken pre- and post-
application: directly from the tank for the
tractor driver and the coarse spray hand-
gunner, and from the handgun itself for the
other applicators.
Inside pads were used only for those
subjects who wore protective gear. Inside
pads were placed immediately inside the
coverall just beneath, but not overlapping,
the outside pad at the following positions:
chest, both forearms, both thighs, and both
shins. While outside pads were without ex-
ception always exterior, inside pads were
occasionally protected by more than the
coverall: either by a rubber apron at the
chest and thighs or by rubber boots at the
shins. If no coverall was worn, inside pads
were protected only by the apron or boots.
Left and right pairs of inside pads
(forearms, thighs, and shins) were com-
bined for extraction and analysis.
Pads, handwashes, and air sampler
plugs were extracted with hexane (or a 70%
hexane-30% acetone mixture, for dicofol
only) and brought from near dryness to a
10 mL volume with hexane (2,2,4-trimethyl-
pentane, for dicofol only).
-------
All analyses were done by gas chroma-
tography using electron capture Ni63
detection.
Results and Discussion
Each exposure was an experiment unto
itself—variations existed in compounds,
compound spray rates, exposure times, ap-
plication methods, subjects, etc. No expo-
sure constituted a true replication of any
other exposure because of these confound-
ing variables that were not under our ex-
perimental control. Any grouping of data,
therefore, is somewhat artificial. Yet, in
order to draw any general conclusions,
some grouping of data into classes was re-
quired. Happily, in practice, there was lit-
tle variation in presumed spray rate (kg ac-
tive ingredient/hr) from applicators' spray
nozzles when a given subject applied a
given compound by a given method. This
suggested grouping all such individual ex-
posures together into subgroups, each
subgroup corresponding to a given sub-
ject/compound/application method, for
which the spray rate varied little from ap-
plication to application. The phrase
"presumed spray rate" suggests some am-
biguity and derives from our observation
that thorough mixing of compound was not
usually accomplished in the spray tank.
Table 1 gives the pre- arid post-spray tank
mixture analyses for concentration, ex-
pressed as percentages of the presumed
concentration. While no statistical dif-
ference existed between the pre- and post-
spray samples, the data showed that for
chlorpyrifos, ethazol, and captan (all for-
mulated as wettable powders), less than
half of the compound presumed to be leav-
ing the spray nozzle, actually was. This cir-
cumstance was less pronounced for
fluvalinate and dicofol (both formulated as
emulsifiable concentrates) and entirely ab-
sent with chlorothalonil, a wettable powder
that unaccountably appeared to be well-
mixed. It is, of course, possible that losses
of compound from the tank mixture
samples occurred during storage prior to
their being analyzed and that the
discrepancy we appear to have detected
between the tank mixture recipe and the
tank mixture itself is spurious. With this
digression as a caveat, we return to our
grouping scheme, whereby all exposures
of a given subject spraying a given com-
pound by a given method are combined.
This done, it was then evident that signifi-
cant differences in mean ETBAR, hand-
washes, and air samples existed between
subjects applying the same compound by
the same method. These differences were
not surprising, given the fact that mean
spray rates also varied among subjects.
There was a general tendency, by no
means without exception, that when large
differences in these exposure parameters
occurred, they were explainable on the
basis of mean presumed spray rate dif-
ferences. This effect was tested by obtain-
ing correlation coefficients between mean
spray rate and ETBAR, handwash, and air
sample data for each of the five work prac-
tices (drencher and assistant excluded). Of
the 15 correlation coefficients, 13 were
positive and averaged 0.629. Consequent-
ly, these three exposure parameters were
all normalized for (divided by) spray rate.
What resulted was a measure of "mg-
deposited/kg-sprayed," the time units hav-
ing cancelled out. These normalized mean
values then did not differ significantly
among subjects within a given com-
pound/application-method class, and sub-
jects were, therefore, combined in Tables
2 through 4. This non-significance among
subjects was confirmed with an ANOVA
(analysis of variance) at p < 0.05. Left and
right mean handwash data also showed no
significant differences (p < 0.05) through-
out and were summed to give "total mean
handwash" prior to the ANOVA and their
inclusion in Tables 2 through 4.
To determine whether differences exist
among compounds for the various nor-
malized parameters and application
methods given in Tables 2 through 4, a
Duncan's Multiple Range Test (p < 0.05)
was applied to each of the pesticide groups.
The few significant differences that were
found are presented in Table 5. The analy-
sis summarized in Table 5 shows that fine
spray and pulse fog handgunners were at
significantly (p < 0.05) more risk to nor-
malized ETBAR (NETBAR) contamination
by fluvalinate than from the other com-
pounds tested. The coarse spray handgun-
ner and the span spray tractor driver, both
of whom also sprayed fluvalinate, were
significantly more at risk to NETBAR
contamination from chlorothalonil and
chlorpyrifos, respectively. Regarding nor-
malized handwash contamination, the
boom spray tractor driver was significantly
more at risk from chlorpyrifos than from
fluvalinate or captan. For normalized air
sampler contamination, fine spray hand-
gunners were significantly more at risk from
ethazol than from fluvalinate, chlorpyrifos,
or dicofol; the boom spray tractor driver was
more at risk from chlorpyrifos than from
fluvalinate or chlorothalonil; the span spray
tractor driver was more at risk from chlor-
pyrifos than from fluvalinate. These dif-
ferences among compounds cannot be ex-
plained at this time.
Comparing the various work practices, it
can be observed from Tables 2 through 4
that the NETBAR data form general
classes. Largest NETBAR values came
from handgunners of all types and the
drencher, moderate values from the boom
spray tractor driver and the assistant are an
order of magnitude lower, and, finally,
lowest values by another order of magni-
tude came from the span spray tractor
driver. There is a further tendency within the
handgunner group for fine spray handgun-
ners to receive more NETBAR than coarse
spray or pulse fog handgunners. These
general trends are more or less pro-
nounced depending upon the chemical ap-
plied. It should be emphasized that the
separation of handgunners by fineness of
spray is a qualitative separation based on
visual observation only and unsupported by
any measurements. For normalized hand-
wash data, there are, once again, three
obvious work practice classifications. Hand-
gunners as a group received the most,
followed by the tractor driver and the
drencher with about an order of magnitude
less hand contamination, and finally the
assistant with a slight amount only. For nor-
malized air sampler data, three classifica-
tions suggest themselves: highest values
are found with fine spray handgunners and
pulse foggers (the assistant assisted a fine
spray handgunner), about one order of
magnitude lower values came from the
coarse spray handgunner and the tractor
driver, and finally the drencher whose air
sampler detected nothing. One possible ex-
planation of this last result is that the finer
the spray, the greater the atmospheric con-
tamination, either because of the smaller
droplet size or because of enhanced
volatilization from surfaces. Another
operating factor may be the type of
greenhouse structure in which the applica-
tion was carried out. Fine spray handgun-
ners and pulse foggers applied pesticide
in enclosed structures; the coarse spray
handgunner applied in an open sided
house; the tractor driver applied in an open
setting, except for a net ceiling. Thus,
fineness of spray is confounded here with
openness of structure. The finer spray
applications occurred in more enclosed
structures. It may be that the enclosed en-
vironment rather than the finer spray is the
critical factor for atmospheric contami-
nation.
Penetration of pesticide through protec-
tive clothing was assessed by computing
the ratio of inside pad flux to that of the cor-
responding outside pad. This value we call
transmittance, a term borrowed from optics.
We do note, however, that inside pads can
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Table 1. Mean Tank Mixes', Expressed as Percents of Presumed Tank Mix
Handgunners
fine spray
pre-spray
post-spray
coarse spray
pre-spray
post-spray
pulse fog
pre-spray
post-spray
Tractor driver
boom spray
pre-spray
post-spray
span spray
pre-spray
post-spray
Drencher
pre-spray
post-spray
All combined
Fluvalinate
90 ± 29 (27)
110 ± 28(27)
51 ± 11 (7)
50 ± 10 (7)
68 ± 28 (7)
72 ± 7 (7)
57 ± 11 (7)
53 ± 10 (7)
94 ± 65 (3)
29 ± 5 (3)
81 ± 8 (102)
Chlorpyrifos Ethazol Dicofol Captan
16 ± 3 (22) 28 ± 4 (19) 57 ± 5 (9)
22 ± 4 (20) 35 ± 5 (18) 69 ± 4 (8)
47 ± 73 (8) 106 ± 25 (2)
48 ± 13 (8) 112 ± 3 (2)
15 ± 8 (3) 19 ± 7 (3)
8 ± 2 (3) 21 ± 7 (3)
45 ± 6(11) 30 ± 7(7)
50 ± 6(11) 36 ± 8(7)
114 ± 23 (3) 91 ± 6(3)
58 ± 24 (3) 66 ± 26 (3)
25 (1)
39 (1)
35 ± 4(94) 37 ± 5(47) 63 ± 3 (17) 47 ± 7(20)
Chlorothaloni
143 ± 39 (3,
91 ± 8 (3j
105 ± 6 (4)
109 ± 5 (4)
111 ± 10(14)
' ± standard error (number of samples)
Table 2. Mean'
Handgunners
fine spray +
coarse spray t
pulse fog +
Tractor driver*
boom spray
span spray
Drencher*
Assistant +
Estimated Total Body Accumulation
Fluvalinate
856 ± 221 (26)
81 ± 71 (7)
65 ± 75 (7)
2.1 ± 0.6 (6)
0.20 ± 0.04 (3)
Rate (ETBAR), Normalized for Spray Rate (mg Deposited/kg Sprayed)
Chlorpyrifos Ethazol Dicofol Captan
229 ± 42(22) 39 ± 9(17) 287 ± 81 (9)
70 ± 24 (7) 26 ± 21 (2)
6 ± 2 (3) 12 ± 4 (3)
4.7 ± 1.1 (10) 2.8 ± 1.0 (6)
0.98 ± 0.23 (3) 0.35 ± 0.73(3;
44 (1)
4 (1)
Chlorothalonil
279 ± 93 (3)
3.8 ± 0.9 (4)
* ± standard error, with number of exposures in parentheses
+ does not include handwash (subjects wore gloves)
t includes handwash (subjects wore no gloves)
4
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Table 3. Mean' Total Handwash, Normalized for Spray Rate (mg Deposited/kg Sprayed)
Fluvalinate Chlorpyrifos Ethazol Dicofol
Handgunners
fine spray*
coarse sprayt
pulse fog*
Tractor driver^
boom spray
span spray
Drencher *
Assistant +
1.7 ± 0.3(27)
5 ±2 (7)
5 ± 1 (7)
0.21 ± 0.05 (7)
0.17 ± 0.03(3)
1.7 ±
7±
13 ±
0.61 ±
0.71 ±
0.55
0.04
1.2 (23) 0.08 ± 0.02 (19) 0.91 ± 0.30 (9)
4 (8) 0.04 ± 0.02 (2)
10 (3) 0.08 ± 0.07 (3)
0.10(11)
0.28 (3)
(1)
(1)
Captan Chtorothalonil
9 ±3 (3)
0.23 ± 0.06(7) 0.41 ± 0.07(4)
0.13 ± 0.04(3)
* ± standard error, with number of exposures in parentheses
+ subjects wore gloves
t subjects wore no gloves
Table 4. Mean' Air Sampler Deposit, Normalized for Spray Pate (mg Deposited/kg Sprayed)
Fluvalinate Chlorpyrifos Ethazol
Dicofol
Captan
Chlorothalonil
Handgunners
fine spray*
coarse sprayt
pulse fog*
Tractor driver
boom spray§
span spray§
Drencher*
Assistant*
0.033 ± 0.006 (27) 0.082 ± 0.046 (23) 0.547 ± 0.232 (19) 0.020 ± 0.006 (9)
0.0088 ± 0.0074 (7) 0.0046 ± 0.0011 (8) 0.1213 ± 0.0761 (2)
0.295 ± 0.141 (7) 0.064 ± 0.037 (3) 0.344 ± 0.733 (3)
0.0019 ± 0.0073 (7) 0.0051 ± 0.0011 (11)
0 ± 0 (3) 0.0020 ± 0.0002 (3)
0.0065 ± 0.0053 (3)
0.0026 ± 0.0008 (7) 0.0072 ± 0.0002 (4)
0.0015 ± 0.0008 (3)
0
0.0143
(1)
(V
' ± standard error, with number of exposures in parentheses
+ applications made in enclosed structure
t applications made in open sided structure
§ applications made in open Siran™ structure
suffer contamination by other routes than
directly through the protective clothing. For
example, samplers observed in the field
that when an applicator extended his arm,
the sleeve of the coverall had a tendency
to ride up, exposing the inside forearm pad.
We intend here to include all such events
in transmittance, with the latter term inter-
preted very loosely. Mean transmittance
over all subjects and work practices is
presented in Table 6. A mean transmittance
of zero indicates that its mean value was
less than 0.005. It is clear from Table 6 that
transmittance depends both on compound
and location on the subject. The data sug-
gest that the transmittance may not, under
field conditions, be a constant value for a
given compound penetrating a given fabric.
There is a tendency for transmittance to be
smaller when outside pad contamination is
larger, as is the case in this experiment with
thigh and shin pads. Note, for example, the
difference in mean transmittance values for
Chlorpyrifos penetrating only the coverall.
Significant differences among compounds
in Table 6 were assessed through a Dun-
can's Multiple Range Test (p < 0.05). Stan-
dard errors were large, so that the only dif-
ferences confirmed were the greater
penetrating ability of ethazol vis-a-vis
fluvalinate and Chlorpyrifos at the chest and
thigh, and vis-a-vis fluvalinate at the
forearm.
Conclusions and
Recommendations
Differences in individual work habits of
those workers applying the same pesticide
by the same method resulted in little varia-
tion in the ETBAR, handwashes, or air
samples. This became apparent only when
these measurements were normalized for
spray rate.
Statistical analyses of the pre- and post-
application tank mixtures showed no signifi-
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Table 5. Significant Differences' Among Compounds + Applied
Normalized
ETBAR
Normalized
handwash
Normalized
air sampler
Handgunners^
(fine spray)
F > CS
F > E
F > D
none
E > F
E > CS
E > D
Tractor Tractor
driver^ driver^
Handgunners^ Handgunners^ (boom (span
(coarse spray) (pulse fog) spray) spray)
CL > F F > CS none CS > F
CL > CS F > E CS > CN
CL > E
none none CS > F none
CS > CN
none none CS > F CS > F
CS > CL
"according to a Duncan's Multiple Range Test (p < 0.05)
+ fluvalinate (F), chlorpyrifos (CS), ethazol (E), dlcofol (D), captan (CN), chlorothalonil (CL)
twore gloves
§wore no gloves
cant difference between the two. But, par-
ticularly for chlorpyrifos, ethazol, and
dicofol (all wettable powder formulations),
less than 50% of the pesticide concentra-
tion presumed to exist in the tank on the
basis of the mixture recipe was actually
found. Fluvalinate and dicofol (both emul-
sifiable concentrates) were significantly
closer to expectations. Chlorothalonil, a
wettable powder, was an exception to the
above dichotomy, with no discrepancy from
expectations.
When the ETBAR, handwashes, and air
sampler data were normalized for spray
rate and expressed in "mg-deposited/kg-
sprayed," these normalized exposure
parameters showed some compound spec-
ificity, and the specificity pattern de-
pended upon the application method. Ir-
respective of compound, however, the
largest normalized ETBAR values came
from handgunners of all types, moderate
values from the boom spray tractor driver,
and lowest values from the span spray trac-
tor driver. These groups were each
separated by about one order of magnitude.
Normalized handwash magnitudes fol-
lowed these same lines, but with little dif-
ference between the two tractor application
methods. Normalized air sampler values
were largest for the fine spray handgunners
and pulse foggers and about one order of
magnitude less for the coarse spray hand-
gunner and the tractor driver.
Pesticide penetrated through Tyvek™
coveralls with a transmittance (% penetra-
tion) of 0% to 23%, depending strongly
upon the potential amount of pesticide to
be transmitted and the compound itself.
Penetration of the compounds through the
coverall at the forearm location was
significantly greater for ethazol than for
fluvalinate. Also, signficantly more ethazol
than fluvalinite or chlorpyrifos penetrated
the coverall/apron barrier at the chest and
thigh.
The present study has established the
potential exposure to greenhouse ap-
plicators and an estimate of the protection
Tyvek™ coveralls afforded. For reasons
not clearly understood, Tyvek™ coveralls
were observed to have much less penetra-
tion resistance against ethazol than against
Table 6. Mean" Transmittance to Inside Pads, All Subjects
Fluvalinate Chlorpyrifos
Ethazol
Dicofol
Chlorothalonil
Chest, covered by
coverall only
apron only
coverall plus apron
Forearms, covered by
coverall only
Thighs, covered by
0.02 ± 0.02(11)
0+ ± 0 (24)
0.04 ± 0.03 (33;
0.72 ± 0.08 (2)
0.05 ± — (1)
0.09 ± 0.04 (24)
0.12 ± 0.06(26)
0.01 ± 0.01 (9)
0.23 ± 0.04 (20)
0.23 ± 0.04 (20) 0.72 ± 0.05 (9)
coverall only
apron only
coverall plus apron
Shins, covered by
boots only
coverall plus boots
0.01 ± 0.01 (11)
0.22 ± 0.13 (4)
0 ±0 (24;
0 ± 0 (7)
0.04 ± 0.02 (31)
0.01 ± 0.00 (2)
0.11 ± 0.11 (6)
0.02 ± 0.01 (24)
0 ± 0 (8)
0.04 ± 0.03 (26)
- 0 ±0 (9)
0.52 ± 0.37 (3) -
0.15 ± 0.03(22; -
0.02 ±002 (2) -
0.02 ±001 (20) 0 ± 0 (9)
-
0.07 ± 0.01 (3)
-
0 ±0 (3)
—
* ± standard error (number of exposures)
+ indicated < 0.005
-------
the other pesticide formulations. Suits
should be constructed with oversized long
sleeves and a closure device at the wrist;
hoods should be part of the suit. Appli-
cators should wear rubber gloves extend-
ing to mid forearm, rubber boots, and
respirators.
Where necessary, pesticide mixing
methods in the tank should be updated,
particularly for wettable powder formula-
tions. This way, better pest control should
result and/or less pesticide could be used.
We further recommend that four addi-
tional coverall fabrics be field-tested for
penetration in a commercial greenhouse
setting. The materials we suggest are Dura-
guard™, SMS, treated twill, and untreated
twill. These materials have undergone a
prior battery of laboratory tests for penetra-
tion at the Department of Textiles, Merchan-
dizing and Design (Dr. J. O. DeJonge,
Head), University of Tennessee, Knoxville,
TN 37996. Handgunners, who constitute
the applicator group at greatest potential
risk, should be employed as subjects. The
compounds monitored should be fluvali-
nate, chlorpyrifos (the two most frequently
applied compounds at our cooperating
facility), and ethazol (of those tested, the
most penetrating compound through
Tyvek™). Field-testing these fabrics for
thermal comfort could best be undertaken
in a separate study conducted elsewhere.
The full report was submitted in fulfill-
ment of grant CR-810743 by the University
of Florida under the sponsorship of the U.S.
Environmental Protection Agency.
-------
H. N. Nigg, J. H. Stamper, and W. D. Mahon are with the University of Florida,
IFAS, Lake Alfred, FL 33850.
Michael Royer is the EPA Project Officer (see below).
The complete report, entitled "Pesticide Exposure to Florida Greenhouse
Applicators," (Order No. PB 88-219381 /A S; Cost: $ 19.95, subject to change)
will be available only from:
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: 703-487-4650
The EPA Project Officer can be contacted at:
Hazardous Waste Engineering Research Laboratory
U.S. Environmental Protection Agency
Edison, NJ 08837
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
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