Pesticide contamination inside farm and nonfarm homes.

Abstract

Twenty-five farm (F) households and 25 nonfarm (NF) households in Iowa were enrolled in a study investigating agricultural pesticide contamination inside homes. Air, surface wipe, and dust samples were collected. Samples from 39 homes (20 F and 19 NF) were analyzed for atrazine, metolachlor, acetochlor, alachlor, and chlorpyrifos. Samples from 11 homes (5 F and 6 NF) were analyzed for glyphosate and 2,4-Dichlorophenoxyac etic acid (2,4-D). Greater than 88% of the air and greater than 74% of the wipe samples were below the limit of detection (LOD). Among the air and wipe samples, chlorpyrifos was detected most frequently in homes. In the dust samples, all the pesticides were detected in greater than 50% of the samples except acetochlor and alachlor, which were detected in less than 30% of the samples. Pesticides in dust samples were detected more often in farm homes except 2,4-D, which was detected in 100% of the farm and nonfarm home samples. The average concentration in dust was higher in farm homes versus nonfarm homes for each pesticide. Further analysis of the data was limited to those pesticides with at least 50% of the dust samples above the LOD. All farms that sprayed a pesticide had higher levels of that pesticide in dust than both farms that did not spray that pesticide and nonfarms; however, only atrazine and metolachlor were significantly higher. The adjusted geometric mean pesticide concentration in dust for farms that sprayed a particular pesticide ranged from 94 to 1300 ng/g compared with 12 to 1000 ng/g for farms that did not spray a particular pesticide, and 2.4 to 320 ng/g for nonfarms. The distributions of the pesticides throughout the various rooms sampled suggest that the strictly agricultural herbicides atrazine and metolachlor are potentially being brought into the home on the farmer's shoes and clothing. These herbicides are not applied in or around the home but they appear to be getting into the home para-occupationally. For agricultural pesticides, take-home exposure may be an important source of home contamination.

Full text

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Bringing Work Home:
Take-Home Pesticide Exposure Among Farm
Families



















Brian D. Curwin

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Cover designed by Inger Williams




Curwin, B.D., 2006
Bringing Work Home: Take-Home Pesticide Exposure Among Farm Families
Thesis, Utrecht University – With summary in Dutch
ISBN-10: 90-393-4358-6
ISBN-13: 978-393-4358-6

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Utrecht University




Bringing Work Home:
Take-Home Pesticide Exposure Among Farm
Families


Insleep van gewasbeschermingsmiddelen en
blootstelling van boerenfamilies
(met een samenvatting in het Nederlands)


Proefschrift

ter verkrijging van de graad van doctor aan de Universiteit Utrecht op gezag van de
rector magnificus, prof.dr. W.H. Gispen, ingevolge het besluit van het college voor
promoties in het openbaar te verdedigen op donderdag 5 oktober 2006 des middags
te 2:30 uur


door


Brian Curwin

geboren 9 december 1968, te Moncton, New Brunswick, Canada

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Promotoren: Prof. Dr. Ir. D. Heederik
Prof. Dr. Ir. H. Kromhout

Co-Promotor:
































This thesis was accomplished with financial support from the National Institute for
Occupational Safety and Health, Centers for Disease Control and Prevention in the
United States of America and from the Institute for Risk Assessment Sciences, Utrecht
University in the Netherlands.
Dr. W. Sanderson

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Contents







CHAPTER 1: INTRODUCTION................................................................................... 1
CHAPTER 2: PESTICIDE USE AND PRACTICES IN AN IOWA FARM FAMILY
PESTICIDE EXPOSURE STUDY................................................................................ 19
CHAPTER 3: PESTICIDE CONTAMINATION INSIDE FARM AND NON-FARM
HOMES.......................................................................................................................... 39
CHAPTER 4: URINARY AND HAND WIPE PESTICIDE LEVELS AMONG
FARMERS AND NON-FARMERS IN IOWA............................................................. 71
CHAPTER 5: URINARY PESTICIDE CONCENTRATIONS AMONG CHILDREN,
MOTHERS, AND FATHERS LIVING IN FARM AND NON-FARM HOUSEHOLDS
IN IOWA........................................................................................................................ 95
CHAPTER 6: PESTICIDE DOSE ESTIMATES FOR CHILDREN OF IOWA
FARMERS ................................................................................................................... 127
CHAPTER 7: DISCUSSION AND CONCLUSION................................................. 151
SUMMARY................................................................................................................. 171
SAMENVATTING..................................................................................................... 179
ACKNOWLEDGEMENTS....................................................................................... 187
PUBLICATION LIST................................................................................................ 189
ABOUT THE AUTHOR............................................................................................ 191


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As crude a weapon as the cave man’s club, the chemical barrage has been hurled
against the fabric of life – a fabric on the one hand delicate and destructible, on the
other miraculously tough and resilient, and capable of striking back in unexpected
ways.
---------------------------------------------------------------Rachel Carson, Silent Spring, 1962



Americans’ occupational deaths, diseases, and injuries cost 155.5 billion dollars per
year, five times the cost of aids, three times the cost of Alzheimer’s disease and almost
as much as cancer.
---------------------------Leigh JP et al., Costs of Occupational Injuries and Illnesses, 2000



Every day:
165 Americans die from occupational diseases
18 Americans die from work related injuries
36400 Americans have non-fatal work related injuries
3200 Americans will acquire occupational illnesses

---------------------------Leigh JP et al., Costs of Occupational Injuries and Illnesses, 2000



Deaf and blind and dumb and born to follow, what you need is someone strong to guide
you.
-----------------------------------------------------------------------------------Tool, Opiate, 1994



Give a monkey a brain and he’ll swear he’s the center of the universe.
----------------------------------------------------------Fishbone, Give a Monkey a Brain, 1993



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1





Introduction


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B.D. Curwin

Background
Take-home pesticide exposure among farm families: Introduction
Para-occupational or take-home exposure occurs when a worker unwittingly brings
home a hazardous substance on his or her clothing or shoes, thereby potentially
exposing his or her family. In 1992, the United States Congress identified this as a
compelling public health issue by passing the Workers’ Family Protection Act (Public
Law 102-522, 29 U.S.C. 671). This legislation directed the National Institute for
Occupational Health and Safety (NIOSH) to conduct a study to evaluate the potential
for, and prevalence of, home contamination of substances brought home by the worker.
NIOSH found that contamination of workers homes was a worldwide problem and
raised it as a concern in the Report to Congress on Workers’ Home Contamination
Study Conducted Under the Workers’ Family Protection Act (29 U.S.C. 671a) (NIOSH
1995). In this large literature review on take-home exposure NIOSH identified several
health effects resulting from home contamination including: chronic beryllium disease,
asbestosis and mesothelioma, lead poisoning with subsequent neurological effects and
mental retardation, deaths and neurological effects from pesticides, chemical burns from
caustic substances, chloracne from chlorinated hydrocarbons, neurological effects from
mercury, abnormal development from estrogenic substances, asthmatic and allergic
reactions from dust, liver angiosarcoma from arsenic, dermatitis from fibrous glass,
epileptic seizure from chemical exposure, and disease from infections agents.

The take-home exposure issue has a long history and is not limited to the United States.
NIOSH reported that death and health effects from contaminants brought home from the
workplace occurred in 28 countries in addition to 36 U.S. states (NIOSH, 1995). They
conclude, however, that the full range and extent to which health effects occur as a
result of worker’s home contamination is not known because there is no monitoring

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B.D. Curwin

system to track related health effects. In addition, physicians do not always recognize
Take-home pesticide exposure among farm families: Introduction
the occupational or para-occupational contribution to common diseases.

While worker’s take home contamination is not new - NIOSH cited published reports of
lead poisoning among lead-workers’ families in the late 1800’s - the problem persists
today (NIOSH, 1995). Half of the reports of health effects among workers’ families
that NIOSH cited in their review appeared between 1985 and 1995. More importantly,
many of these reports identified new sources of contamination.

Lead was one of the first and most extensive compounds to be investigated for home
contamination by this route. In the late 1970’s the lead concentration in dust from lead
workers’ homes was being measured (Baker et al., 1977; Koplan et al., 1977; Winegar
et al., 1977; Dolcourt et al., 1978; Rice et al., 1978; Watson et al., 1978 – for an
extensive list of studies prior to 1996 measuring workers’ home contamination of lead
and other chemicals, the reader is referred to NIOSH, 1995, table 15, pages 184-205).
Take-home pesticide exposure has also been investigated historically; however, recent
attention has been given to studying newer pesticides that are being used (Table 1).

Exposure to pesticides can occur through several pathways and routes, both directly and
indirectly. When directly handling pesticides, i.e. mixing and applying pesticides,
exposure generally occurs via the skin, but inhalation and indirect ingestion can occur as
well. Indirect exposure through contaminated surfaces can be more complex. In farm
environments for example, family members can be exposed by all routes through
several pathways: inhalation exposure via application drift or re-suspension of
contaminated dust and soils, skin exposure through contact with contaminated surfaces,

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soil outside the home or dust inside the home, and indirect ingestion exposure through
Take-home pesticide exposure among farm families: Introduction
hand to mouth contact after touching contaminated surfaces (Figure 1).

Figure 1. Sources of exposure for farm family members.

Children, particularly young children, generally do not directly handle pesticides except
perhaps in developing countries. However, they can nevertheless be exposed to them.
They may play in fields that have been treated with pesticides, or help with farm chores
that may inadvertently expose them to pesticides. Another source of potential pesticide
exposure for children is through the take-home pathway whereby pesticide applicators,
farmers, farm workers or others unwittingly contaminate homes through track-in on
shoes and clothing. Pesticide track-in has been clearly demonstrated after residential

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B.D. Curwin

application of herbicides to lawns. Nishioka et al (1999, 2001) measured the
Take-home pesticide exposure among farm families: Introduction
distribution of the herbicide 2,4-D in homes within a week of a lawn application, and
showed that transport mechanisms were dominated by track-in from active dogs, the
home-owner’s contaminated shoes, and the children’s shoes when worn indoors. Lewis
et al (2001) found that chlorpyrifos residues in indoor air and in carpet dust were higher
within a few days after an exterior residential application than before the application,
and suggested that track-in was the principal source of these residues.

Children are thought to be more susceptible to pesticide exposure than adults due to a
variety of factors including physiology, metabolism, food consumption patterns and
activity patterns. Children’s respiratory rate, heart rate and metabolism are significantly
different from adults (Bearer, 1995) as are food consumption patterns (Health Council
of the Netherlands, 2004; National Academy of Sciences, 1993). Children’s activities
place them at risk of exposure to pesticides when in a contaminated environment
through object and hand-to-mouth behavior and close contact with the ground and
children have a greater skin surface area per kilogram body weight than adults
(Renwick, 1998). These factors can result in different sources and levels of pesticide
exposure for children than adults in the same scenario (Garry, 2004).

Parental occupation involving pesticide application and household pesticide use may be
associated with childhood cancers. A study by Flower et al. (2004) found an increased
risk for all cancers (SIR 1.36, 95 % CI 1.03-1.79) among 17, 357 children of Iowa
participants in the Agricultural Health Study (Alavanja et al., 1996) – a prospective
epidemiology study of farmers in Iowa and North Carolina – compared to the expected
cancer incidence for Iowa. However, no association was detected between frequency of

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B.D. Curwin

parental pesticide application and childhood cancer risk. An increased cancer risk was
Take-home pesticide exposure among farm families: Introduction
seen among children of fathers who did not use chemically resistant gloves (OR 1.98,
95 % CI 1.05-3.76) and who used aldrin prenatally (OR 2.66, 95 % CI 1.08-6.59). Ma
et al. (2002) found a significantly increased risk of childhood leukemia (OR 2.8, 95 %
CI 1.4-5.7) with the use of professional pest control services at any time from one year
before birth to three years after.

Children are not the only people potentially affected by take-home pesticide exposures.
Female spouses of farmers may also be exposed via this pathway and women may
experience adverse health effects different from men. Studies have suggested that
women may have birth malformations, abortions, congenital defects, and other adverse
perinatal outcomes as a result of pesticide exposure (Garcia, 2003; Schreinemachers,
2003). These studies however, generally involve direct exposures to pesticides but take
home exposure may also be occurring.

While chronic toxicity to low levels of pesticide exposure through the take-home
pathway is a concern, acute pesticide poisoning has also occurred, although not
recently, as a result of take home-exposure. An 18 month old girl was poisoned by
demeton when her father, a pesticide applicator, came home with contaminated shoes
(West, 1959). Wives of workers had signs of kepone poisoning after poor hygiene
practices in a chemical plant that manufactured kepone led to contamination of the
workers homes (Cannon et al, 1978; Taylor et al, 1978; Kelly 1977). The use of less
toxic pesticides in recent years has most likely led to the elimination of acute poisoning
from take-home pesticide exposure.


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In the last decade, some attention has been given to the take-home exposure pathway as
Take-home pesticide exposure among farm families: Introduction

7
a source of chronic exposure to pesticides. After a literature search, 13 papers were
identified that examined pesticide home contamination and exposure among farmers or
agricultural workers and their families via this route (Table 1). Of these thirteen papers,
six papers were from two studies for a total of 9 separate study populations. The
majority of these studies focused on organophosphates and other insecticides and
focused on agricultural workers as opposed to farmers. The methodologies from the
studies vary widely and may include environmental (e.g. dust, surface wipe), personal
(e.g. hand wipe) and biological sampling (e.g. urine). Of the 13 studies, only six
include environmental or personal sampling with biological sampling, while only two
includes environmental, personal and biological sampling.

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Table 1. Summary of studies investigating the take-home pesticide exposure pathway.
ReferencePopulation # of subjects
# of samples
Azaroff, 1999 Farmers and family
members 8 yrs and older
living in an agricultural
communities.
Bradman et
al, 1997 farm-worker families.
14 dust
11 hand wipe
Coronado et
al, 2004a
children aged 2-6 years
living in agricultural
communities.
422 urine
Curl et al,
2002a
children aged 2-6 years
living in agricultural
communities.
Fenske et al,
2002b
younger of pesticide
applicators, farm-workers
and reference subjects.
218 urine
218 hand wipe
225 surface wipe
Hogenkamp
et al, 2004 households. 27 samples
Koch et al,
2002 living in an agricultural
community.
998 urine
Loewenherz
et al, 1997b
living with pesticide
applicators and reference
children.
Sample
media
Urine
Pesticides analyzed Results
108 households
358 samples
Organophosphate
Pesticides
The best predictors for the presence of urinary OP metabolites
included living in a household whose head farmer had applied
OP’s.
Farm-worker and non 11 households
Dust, hand
wipe
33 different pesticides
in dust, 9 in hand wipes
Diazinon and chlorpyrifos were higher in dust from farm worker
homes vs. non-farm worker homes.
Farm-workers and their
211 households
(211 children)
346 dust
Dust, urine Azinphos-methyl
Organophosphate
Pesticides
Farm workers who thin crops were more likely to have detectable
levels of Azinphos-methyl in their homes. Workers, who mixed,
loaded, or applied pesticides had less detectable samples in house
dust.
Azinphos-methyl concentrations in house and vehicle dust and OP
metabolite levels in child and adult from same household were
significantly associated.
Farm-workers and their
218 households
346 dust
424 urine
Dust, urine Azinphos-methyl
Organophosphate
Pesticides
Children 6 years old or
75 households
(109 children)
75 dust
Dust, urine,
hand wipe,
surface wipe
Chlorpyrifos, Parathion Homes with agricultural workers or in close proximity to pesticide
treated farmland had higher pesticide concentrations in dust, but
children in these homes did not have higher exposure.
Farm and non- farm 27 households Dust 7 pesticides used in
flower bulb farming
Organophosphate
Pesticides
The odds for detecting pesticides were higher in farmers’
compared to non-farmers’ homes.
No differences in urinary OP metabolite levels were seen due to
parental occupation (farm worker vs. all others) or proximity to
fields.
DMTP levels in urine were significantly higher and percentages of
detectable samples were greater in applicator children.
Children, 2 – 5 years old
44 households (44
children)
Urine
Children up to 6 yrs old
62 households
(88 children)
160 urine
Urine Organophosphate
Pesticides

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Lu et al,
2000b
Children 9 mo to 6 yrs old
living in an agricultural
community.
76 households
(109 children)
75 dust
218 urine
218 hand wipe
225 surface wipe
24 households
48 dust
Dust, hand
wipe, urine
Organophosphate
Pesticides
Median house dust OP concentrations were significantly higher in
agricultural homes. Median pesticide metabolite concentrations
were higher in agricultural children.
McCauley et
al, 2003
Agricultural and reference
families.
Dust Organophosphate
pesticides
Pesticide residues in house dust were significantly associated with
the number of agricultural workers in the home. Mean pesticide
levels were higher in the homes of workers who waited more than
two hours to change out of work clothes.
Agricultural pesticide exposure was associated with housing
adjacent to agricultural fields and pesticide application work.
Quandt et al,
2004
Farm-worker families
with at least one child less
than 7 yrs old.
41 households
(82 adults, 41
children)
82 surface wipes
41 hand wipes
59 households
59 soil
59 dust
218 households
436 urine
436 dust
Hand wipe,
surface wipe
21 pesticides: 8
agricultural and 13
residential
Simcox et al,
1995
Farm, farm-worker and
non farm families.
Dust, soil Azinphos-methyl,
phosmet, chlorpyrifos,
parathion
Organophosphate
pesticides
Household dust concentrations were significantly higher in
farmer/farm worker homes
Thompson et
al, 2003a
Farm-workers and their
children aged 2-6 yrs old.
Dust, urine Pesticide levels above the limit of quantification were seen in a
majority of urine samples from the children of agricultural
workers and in dust samples from agricultural workers homes.
Azinphos-methyl concentrations in house and vehicle dust and OP
metabolite levels in child and adult from same household were
significantly associated.
Papers with an a are from the same study and papers with a b are from the same study.