Field report
 Pesticides,  Agriculture, and Hot Weather

            in  the Mississippi Delta
                      Steve Shapiro
                   Occupational Safety Branch
                   Field Operations Division
                   Office of Pesticide Programs
                       October 1990

                          I visited Mississippi during the week of August 27 - 31, 1990,
                    to assess problems of heat stress, pesticide handling, and the use of
                    protective clothing and equipment in agriculture under very hot, humid
                    conditions  and to  assess how these problems are managed.  Earl
                    Dotter, a photographer under contract with EPA, travelled with me.

                          Robert McCarty of the Mississippi Department of Agriculture
                    and Commerce (MDAC) provided members of his staff to take us
                    around.  Mike Ledlow, Mickey Sims, and Bobby  Moore were
                    thoroughly knowledgeable guides.  They  took us to over 19 sites
                    where pesticides were handled and numerous other places where
                    people were doing field work in the  heat.

                          After arriving in Jackson, we  travelled west through
                    Mississippi's "Hill Country,"  visiting three  aerial pesticide applicators,
                    and continued on  to the Mississippi Delta,  where  we spent  the
                    remainder of the week.  On three afternoons, the  temperature was
                    around 105F.  There had been no rain since about May 21.  The
                    main crops we saw in the Delta were cotton, soybeans,  and rice.
                    There were also significant crops of  milo (a grain sorghum) and
                    pecans, and extensive "aquacultural"  farming of catfish.  We were told
                    that catfish ponds  generally were built on pans of farms where the
                    soil was poorest.
                          My impression from talking to aerial pesticide applicators was
                   that the State of Mississippi's pesticide program had an excellent
                   working relationship with  them.  Many people felt that pesticide
                   safety has improved greatly over the years and is  continuing to
                   improve.  The flying services we  visited usually had one or two
                   planes. We were told that this is characteristic of flying  services in
                   Mississippi and throughout the United States.  Most aerial applicators
                   spoke with pride about their practices and the way their
                   mixing/loading stations were set up.  Almost all the aerial
                   mixing/loading stations we saw were neat and well-kept.  The  ground
                   at most loading areas was covered with concrete,  sloped towards a
                   drain for collecting  the planes' wash water.  Many aerial  applicators
                   expressed interest in and enthusiasm  for the  work  of EPA's

Occupational Safety program.  Some asked us what we thought they
might do to improve their operations.

       The mixing/loading stations which we saw for ground
applications did not compare with those for  aerial applications.  One
aerial applicator complained that ground applicators were not
effectively regulated and "can do anything they want."  A second
aerial applicator said that farmers who  apply pesticides with ground
machines are allowed to do sloppy work and get away with illegal
disposal.  One  of our guides said that the state may increase
enforcement at "High Boy" tractor applications next year.

       Many pilots, especially older pilots, spoke with respect about
the toxicity of  pesticides and appreciated the trend towards pesticides
that  were less "hot" (toxic).  The loaders we met (people who mix
and  load pesticides, who are called "loader boys" in Mississippi) did
not express an  opinion about this  issue.  Most of these loaders were
younger men, who  may have been working for the season at
minimum wage.

       The loaders  concentrated on loading the planes quickly.  Some
wore shorts.  Half  wore  tennis shoes.   We saw only two loaders
wearing long-sleeved shirts.  The choice of clothing most by loaders
was  dictated  more by the hot weather than concern about being
splashed or coming  into  routine contact with pesticide-covered
surfaces.  Some loaders wore rubber gloves.  Most did not.  Few
wore protective aprons, although loaders at two different locations,
who had been  working without  aprons  (one  was wearing a sleeveless
shirt, the other a short-sleeved  shin), put aprons on  to demonstrate
mixing  and loading  in protective clothing for Earl's photographs.  The
loader wearing a sleeveless shirt got very hot working with  the  apron

       We saw one loader with ten years' experience loading  methyl
parathion.  He  wore a short-sleeved shirt and jeans with holes in the
front, but no protective clothing or equipment.  The cuffs of his jeans
hung below his heels and were  soaked  with  methyl parathion wash
water.   Methyl parathion is a Tox I insecticide.  More on methyl
parathion under "Hygiene and Protective Clothing"  below.

       At the only  active ground application mixing/loading operation
we observed, two workers were mixing and  loading pesticides into  a
tank on a "High  Boy" tractor.  The loader wore a cap, a short-sleeved
shirt, long pants,  leather  shoes, and rubber gloves.  The tractor driver
put on leather gloves when he  helped with the loading.  The
pesticides were Prep (Prep is ethephon, a plant growth regulator, Tox
I eye and skin  irritant; full-length  trousers, long-sleeved shirt,

                    protective gloves, and goggles or face shield required on the label)
                    and Def 6 (Def 6 is butifos, a cotton defoliant, Tox IE; hat, long-
                    sleeved shirt, long-legged trousers, rubber or neoprene gloves  required
                    on the label).   The  "High Boy"  tractor had an enclosed cab with air-
                    conditioning and was similar to  the other "High Boy" tractors that we

                           If loaders and applicators wore the  protective clothing  and
                    equipment required  under EPA's proposed  Worker Protection
                    Standards,  it would be a significant departure from what we observed.
                    One pilot active with the Mississippi  Agricultural Aviation Association
                    said that loaders wear protective clothing and equipment until the
                    weather gets hot. Another pilot said  that the heat was  "too much for
                    suiting up  in protective  clothing."   More on protective clothing

                           I  was impressed  by the levels  of  pride and awareness about
                    pesticide safety and the quality of the mixing/loading stations  at the
                    aerial pesticide application operations  we visited.   Most aerial
                    applicators expressed a desire to do things  right and were receptive  to
                    making further improvements. While none of the handlers I observed
                    wore  all  the protective clothing  and equipment required on the
                    pesticide labels, I believe that most would  readily follow appropriate
                    protective measures, if these measures made sense in their working
                           The cockpits of agricultural aircraft can get very hot, due to a
                    "greenhouse effect" from the sun's radiation and to a tremendous
                    amount of heat coming  off the engine, which  is in front of the
                    cockpit.  We were told  that about half of all agricultural aircraft has
                    air-conditioning.  Nearly every plane that we saw had air-conditioned
                    cockpits.  Most pilots swore by their air-conditioning.  A typical
                    comment was, "Air-conditioning is about the best thing that ever
                    happened  to a pilot."  Another pilot who had  installed air-conditioning
                    on his planes said that he would no longer try to operate his business
                    without it.  A third pilot said  that pilots  are "more alert" with air-
                    conditioning than they are without it.  Most aerial applicators with
                    whom I spoke said that they appreciated the engineering controls
                    which  have become available over the years to reduce their exposure
                    to  pesticides.

       We saw several cockpit  air-conditioning systems:  air-driven,
electric, and engine-driven.   One person told us that air-conditioning
pressurizes a cockpit with clean air.  (The cockpit is either totally
enclosed or has a small air port on top towards the rear.)  Another
person told us that cockpit  seals are not sufficient to keep cockpits
free of pesticides.  Most systems deliver cool air in front of the pilot,
directed towards the chest.  One configuration that we saw delivers
air in two streams behind the pilot, above each shoulder.

       Some pilots spoke about their experiences spraying pesticides
before they had air-conditioning.  In Flora, Mississippi, Rudy   _
Holcomb, a pilot who is also the president of the  Mississippi
Agricultural Aviation Association, said that before air-conditioning in
cockpits became available, he would have a continual headache
throughout the flying season each year from May  through  October,
due  to "poison" (pesticides) and the heat.  He would also get what he
described  as a "low burning" all over his body, lie awake  all night,
and  use nerve pills in order to  sleep.  These effects obviously
decrease a pilot's ability  to fly  safely.

       Edgar Hobbs of the  Mississippi Agricultural Aviation Board
(and a former spray pilot himself)  and Buddy Box, an aerial
applicator, told how they used to experience psychotropic effects from
methyl parathion.  They said they also knew other pilots who
experienced these effects.  Methyl  parathion would make  them "do
crazy things."  A powerful  impulse would come over them and they
would find themselves flying their  plane into familiar obstacles  on  a
field, such as a tree,  because they felt a strong desire to clear these
obstacles out of the  way.  They also spoke about  "pilot exhaustion"
arising from both the heat and long hours of flying.  The issues of
psychotropic effects  and exhaustion among pilots who do not have
air-conditioning may  bear further investigation.  [The subject of
psychotropic effects  among  aerial applicators is discussed in
"Organophosphorus Ester Insecticides:  Chronic Toxicity:
Psychopathological Effects," in  Ecobichon  and Joy's Pesticides and
Neurological Diseases, CRC Press, Boca Raton,  1982, pp.  167-171.]

       Other anecdotes we  heard about pesticides and aerial
application safety included:

       t      A pilot said that he got sick from methyl parathion
              last year during take  off.  Just before he took off,
              he had helped "load" (perhaps both mix and load?)
              methyl parathion.

       t      A pilot found pyrethroids (such as Payoff, a Tox
              I insecticide)  going through  the  air-conditioning
              system into the cockpit after  the rubber cockpit
              seals   were  no  longer  performing   like  new.
              Pyrethroids are toxic to the  nervous  system. This
              pilot said that, even  though he has replaced  the
              rubber seals, his face  "bums up" when  he flies all
              day long.  His loader's face gets bumed  too.  He
              stresses  washing,  but  last  year  his   loader  got
              pyrethroid in  his eye.  The loader  had ignored the
              pilot's  instructions.   The  pilot said  that  he plans
              next year to get a face guard for his  establishment.
              He also said that the "mental stress of the job and
              mental fatigue" lead to pilot accidents.

       A   pilot   gave   us   his   assessment   that   most   accidents
characteristically happen with a tank overload on a short strip, "usually
a heavy load, after lunch,  mostly about  1  p.m."  He  and  one  other
applicator also noted that "when  you're  sweating, pesticides  go right
through your  skin."

       One  pilot  said that, before  he got air-conditioning, he would
keep cool by  soaking towels  in an ice water tank  and flying with the
towels wrapped around him.  On  occasion, he would also have his
cockpit filled  with cool water while he sat in it, transforming the
cockpit into a bathtub to  cool him off.

       We did not observe  any  pilots wearing protective clothing or
equipment for pesticides.  The standard  protective  gear we saw pilots
using were crash  helmets and shoulder harnesses.  The pilots wore t-
shirts,  short-sleeved shirts, trousers,  and regular footwear.

       The frequency that flying services washed the  exteriors of their
planes  differed from place to place.  Some applicators said that they
routinely washed  their planes daily or more  often.   Others said that
they did this once or twice  a week.  Many cockpit interiors are
coated with  epoxy.  Washing the  interiors of planes ranged from once
a week to twice a year.

                          "Closed" mixing systems were used at many of the aerial
                    application establishments we visited.  We saw a variety of models.
                    One applicator, Buddy Box, was building a mixing system himself
                    with his own innovative design.  Another applicator showed us a
                    "totally hands-off mixing system  he plans to install.  Where closed
                    systems  were used, we saw some  loaders still doing secondary mixing
                    in open  buckets and collecting and carrying dilute pesticides in open
                    buckets from washing out spray systems.

                          I have questions about the  design of at least one of the
                    "closed" systems we saw.  At one airstrip, a loader, dressed  in shorts,
                    a short-sleeved jersey, a billed cap worn backwards, and tennis shoes,
                    was using a  "Captain Crunch"  system to mix  methyl parathion.  The
                    "Captain Crunch" slashes a  five-gallon metal can through  the bottom
                    and crushes  and rinses it.  As the loader crushed and rinsed  one can,
                    I saw  parathion splash out the  rear of the device.   I wonder whether
                    the parathion could have just as easily splashed  out the front on the
                    loader.  More on methyl parathion under "Hygiene and Protective
                    Clothing" below.

                          We saw some loaders using a "probe," a specially-designed
                    nozzle with a pointed end.  (This  device is also known as a "pressure
                    rinse  nozzle.")  A probe screws onto a  standard water hose and serves
                    the combined functions of puncturing plastic  containers, "triple-
                    rinsing"  (actually power rinsing), and rendering the containers useless.
                    Probes were  distributed widely under a  special program of MDAC.

                          Many places  used a  device called a "dry couple," which
                    connects the  hose coming off the mixing tank or holding  tank  to a
                    connection to a plane's pesticide tank.  This  seems like a good
                    device.  We  saw some spillage where dry  couples were not used.
                    But there was also a little spillage with  some of the dry couples we
                    saw.   Some  loaders  wore rubber gloves  when connecting and
                    disconnecting hoses  to aircraft pesticide  tanks, others did not.

                          One aerial applicator recounted how loaders used to get sick
                    from handling bags of Lannate insecticide because there  were  no
                    warnings on the  bags.  (Lannate is methomyl, a wettable powder, Tox
                    I; protective clothing, goggles, and respirators  now required on the
                    label.)  He also showed us containers of Blazer (the herbicide
                    acifluorfen, a Tox I eye and skin irritant) and Triton CS-7 (a Tox II
                    oil emulsifier spreader binder),  which look similar and have  the  same
                    shape and colors. He was concerned that there  could be accidental
                    poisoning  if workers confuse these similar containers.  This applicator
                    said that handling bags of pesticides used for rice was particularly  hot
                    work. Another aerial applicator had a forklift truck for moving  55-
                    gallon pesticide drums, eliminating most  manual handling of these
                    heavy containers.

                          We learned of several ways of how empty pesticide containers
                    were disposed.  Some pesticide manufacturers  and formulators have a
                    "boomerang" system, where they take back their 15- or 20-gallon
                    stainless steel drums for re-use.  MDAC  established a pilot program
                    in Washington County with the National  Agricultural Chemicals
                    Association to collect triple-rinsed  or power-rinsed containers.  Plastic
                    and metal  containers are separated and compacted and  baled at a gin.
                    About 500 plastic containers  make a bale.  The  products from
                    recycling include plastic flower pots and  ~ pesticide containers.  This
                    program is being expanded to other counties.
                          The most common vessels in which workers carried drinking
                    water to the fields were two- and three-gallon portable water coolers.
                    Equipment operators typically carried a cooler by their seat. Field
                    workers  got water from coolers kept in the beds of pickup trucks.
                    Some workers said that they found  the coldness of ice water
                    disagreeable and preferred cool water to ice water.  Some farmers
                    supplemented drinking water for their workers with cans of soft drinks
                    kept in cooler chests.  Three women "chopping cotton" (hoeing weeds
                    in a cotton field), who were not regular field workers, said they often
                    went the entire workday in the field from 7 a.m. to 1 p.m. without

                    drinking any water because "it took too much time" to walk across
                    the field to the pickup truck to get water.  No other workers indicated
                    that they  found it inconvenient to go for drinking water.  Drinking
                    water was available at virtually every work site we visited.  Other
                    field workers told us how much water on average  they drank during
                    the workday.  This ranged from one  gallon to two gallons.

                          The workers we observed seemed to pace themselves, taking
                    breaks when they thought they needed to. Two workers who were
                    Army veterans indicated the greatest  awareness of keeping well-
                    hydrated and taking rest breaks to  cool off.  This is understandable,
                    given the Army's extensive program  to prevent heat illness.  One
                    worker, a member of a crew hand-rouguing a rice  field, said that he
                    will customarily take a  break for fifteen minutes, even for an hour, if
                    he gets very hot.  The second worker, a  Vietnam veteran who works
                    for his brother, offered  a program on  the spot to manage heat stress:
                    drink plenty of water, take breaks when you need them, and don't let
                    any  employer push you to keep on working when you need  a break
                    from the heat.

                          The Army had made believers  in heat  stress prevention out of
                    the two veterans.  This  is encouraging.  Employer  commitment and
                    effective worker training should be able to reduce substantially the
                    incidence  of heat illness throughout agriculture, although use of
                    protective clothing presents some special  problems.

                          One of the workers hand-rouguing rice said he often gets  heat
                    cramps at night.  We discussed the standard remedy for normally
                    healthy persons with heat cramps   light salting of food.
                          While enclosed, air-conditioned cabs on mobile equipment were
                   in wide use, we also saw many open tractors.  Canopies, which give
                   shade, were universally popular with  workers.  One tractor driver with
                   many years' experience said that this was the first year his tractor had
                   been equipped with a canopy.  He said he didn't like air-conditioning,
                   but he liked his canopy.

                          There were canopies over many of the aerial applicator mixing
                   stations we visited.  Loaders said that canopies made  a big difference


                    in reducing heat.  One aerial applicator who had a canopy over the
                    mixing station at his home airstrip said that he did not have canopies
                    at his satellite air strips, but he was going to put them up.

                           Some  mixing stations were equipped with fans, both to cool
                    the loaders and to blow pesticide fumes away.  Most mixing  stations
                    that we visited were not equipped with fans.  In Yazoo  City, an
                    applicator said that  a fan had not worked out for his mixing station
                    because the wind often shifted in three different directions.
                          One farmer who operated his own flying service  said his
                    pesticide handlers were given training  every year.   He said he didn't
                    see the need for the federal government to require  training because he
                    already takes  care of this on his own.   No other person  mentioned
                    training  to us during the week.
                          I sympathize with applicators over the problem of working in
                    protective clothing and equipment in the heat.  One applicator said
                    that "the main threat to the loader is heat exhaustion."  This sentiment
                    was echoed by others.  We observed only one loader wearing nearly
                    all required protective clothing for the  pesticide he was mixing,  and
                    he was very hot.  He was mixing and loading the insecticide Larvin
                    3.2 (thiodicarb, a  Tox II insecticide/ovicide) in 105-degree heat.   He
                    wore all the clothing indicated on the  label, except for a head
                    covering.  In  addition, he wore a face  shield, a rubber apron, and
                    rubber boots,  which were not required  by the Larvin label and which
                    undoubtedly added to his heat  stress.   He was still cooler than he
                    would have been  had he been  mixing  methyl  parathion  wearing  the
                    chemical-resistant  protective coveralls required for handling methyl
                    parathion.   All but one of the other loaders we saw mixed and loaded
                    pesticides,  which just happened always to include methyl  parathion or
                    Prep  (both Tox I), in short-sleeved shirts and  various inadequate
                    clothing ensembles.

                           One person spoke of his and his workers' abhorrence of
                    wearing rubber boots on concrete.  A loader at another establishment
                    spoke of the "impossibility" of wearing rubber boots on concrete.
                    What can be done for people  for whom rubber boots are a problem?
                    Rubber boots are required for handling certain pesticides; concreting
                    the ground is an effective means to keep mixing/loading stations
                    sanitary and control  pesticide-contaminated wash water  from planes.

                           I discussed the use of cooling vests to make protective clothing
                    more tolerable for loaders in the heat. No one had ever heard of
                    cooling vests, but several applicators said they would like to try Them
                    out.  I also discussed cooling  vests with Robert McCarty.  He said
                    that  MDAC is amenable to a trial program to assess their suitability.

                           Most applicators may understandably consider it inhumane to
                    make their workers wear the full protective clothing ensembles
                    required on the labels of Tox  I and Tox II pesticides  in very hot
                    weather, unless effective cooling devices, such as cooling vests,
                    become available.  I hope that EPA's heat  stress management
                    program, the training requirements under the  new Worker Protection
                    Standard, and related activities by  MDAC will help.
                           With few exceptions, the clothing we saw worn by  most
                    loaders, pilots, and ground applicators seemed to be the same clothing
                    they wore outside of work.  Most loaders and applicators wore regular
                    hot weather clothes, including short-sleeved or sleeveless shirts, shorts
                    or long-legged pants, and tennis shoes.  Avoiding heat stress only
                    partially explains this.

                           At one operation, an aerial applicator said that he and his
                    workers do not wear protective gloves because the gloves are
                    uncomfenable.  He also noted that methyl parathion is particularly
                    hard on the diaphragms inside aircraft spray nozzles.  It distorts the
                    diaphragms' shape  and they have to be replaced. He  said  that he and
                    his  employees use  their bare hands when they worked on sprays,
                    relying on  "plenty  of soap and water" to wash pesticides off
                    themselves.  We watched  one  of his  workers replacing spray
                    diaphragms with his bare  hands  after a plane had made  a run with
                    methyl parathion.   I told the applicator that there are  manufacturers

who make specially-lined gloves,  which they claim are comfortable,
and I suggested that he ask MDAC where he can obtain these gloves.
Interestingly, one of the pilots who works for this applicator does not
get out of the cockpit at all during the workday,  even to eat lunch.
He eats his lunch in the cockpit.

       Two applicators told us that they used surgical gloves  for
protection, throwing them away after each use.

       Most applicators we met expressed a sincere desire  to  work
safely, but many did not view wearing protective clothing and
equipment as very important.   Some pilots expressed  awareness of
low-level  and sub-clinical effects of exposures to pesticides.  This is
understandable, given that the demands of flying  safely require pilots
to have unimpaired mental performance.  It  may  be that ground
workers accept or even ignore low-level symptoms and subtle
neurobehavioral effects of exposures to pesticides. Pilots are  probably
getting exposures when they hold on to the  exterior surfaces of their
planes with their bare  hands while climbing  in and out between loads
when they are  applying Tox I and Tox II pesticides.  (See
requirements for methyl parathion below.)  Pesticides  can also enter
enclosed cockpits through leaking cockpit seals, air ports, and, of
course, open air vents.  I wonder how much exposures to certain
pesticides also  affect applicators and loaders when they drive  motor
vehicles outside of work.

       Although some aerial applicators told us that their employees
were generally  familiar with the requirements on  pesticide labels, what
we saw indicated that  they mainly relied for protection on  their
mixing/loading  equipment,  minimal protective clothing (gloves) to no
protective clothing, and, at aerial stations, wash water for emergencies.
Some aerial applicators said that they and their workers wore
protective gloves or surgical gloves faithfully, although it was clearly
the preference of pilots and loaders at many establishments not to
wear gloves at  all.  At many  of the aerial application establishments
we visited, the  requirements for protective clothing and equipment
printed on the pesticide labels did not seem  to be much of a concern;
the focus  of attention,  understandably, was on accomplishing the
immediate mixing/loading and application tasks  at hand.

       We did  not see any handlers or applicators wearing  ordinary
coveralls or chemical-resistant suits, nor did  we see anyone wearing  a
respirator  for protection, even when a respirator was required, as it is
for open mixing of methyl parathion.  Loaders would show us their
respirators when we asked  to  see them.  All the respirators were the
dual-cartridge type and looked like new.  We also saw two new
respirators hanging on a coat rack on the wall of the  office of one

flying service.

       EPA's registration standard and the pesticide label for the Tox
I insecticide  methyl parathion require loaders to wear a long-sleeved
shirt, long-legged pants, chemical-resistant gloves, a chemical-resistant
apron, and shoes and socks when closed mixing/loading systems are
used.  Goggles or a face shield, must  be  worn when the system is
under pressure.  A  protective coverall  or two-piece protective suit,
goggles or a face shield, a hood or wide-brimmed hat, chemical-
resistant shoes  (or chemical-resistant shoe coverings or chemical-
resistant boots), and a pesticide respirator must be available nearby
and  worn during repair and cleaning of application equipment or if
open mixing/loading is done.  Pilots in enclosed cockpits must wear a
long-sleeved  shirt, shoes, and socks; and wear chemical-resistant
gloves when  getting in and out of the plane.  Loaders  and applicators
must shower and change to clean clothes  before leaving the job.
Except  for pilots wearing long-legged  trousers, we saw no indication
that  any of the above  provisions were followed.

       Some flying services used mobile homes or modular structures
for their offices.  We  saw bathtub/showers in the bathrooms of some
of them.  The showers did not seem to be actively used.  We saw
one  bathtub used to store manuals and other documents.  I don't think
it would be difficult for most flying services to upgrade their hygiene
program for pilots and  loaders who handle methyl parathion  and other
pesticides requiring stringent hygiene.   But even if existing showers at
flying service offices were put into use, the problem of pilots and
loaders  entering offices in contaminated clothing would remain, unless
a company built a change room connected to the bathroom, with a
separate entrance to the  outside.
                               * * *

       This trip broadened my perspective on problems of pesticide
handling and agriculture under very hot conditions.  These problems
are common to other parts of the United States.  I hope that the
insights gained from this trip can improve the work of EPA.

       My travel was funded by the Agricultural Research Institute.
ARI was established by the National Academy of Sciences National
Board  of Agriculture  to link agricultural research in academia,
industry, and government.  ARI's support and MDAC's assistance,
particularly that of Robert McCarty, Mike Ledlow, Mickey Sims, and
Bobby Moore,  are deeply appreciated.