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Workplace, household, and personal predictors of pesticide exposure for farmworkers.

In this article we identify factors potentially associated with pesticide exposure among farmworkers, grade the evidence in the peer-reviewed literature for such associations, and propose a minimum set of measures necessary to understand farm worker risk for pesticide exposure. Data sources we reviewed included Medline, Science Citation Index, Social Science Citation Index, PsycINFO, and AGRICOLA databases. Data extraction was restricted to those articles that reported primary data collection and analysis published in 1990 or later. We read and summarized evidence for pesticide exposure associations. For data synthesis, articles were graded by type of evidence for association of risk factor with pesticide exposure as follows: 1 = association demonstrated in farmworkers; 2 = association demonstrated in nonfarmworker sample; 3 = plausible association proposed for farmworkers; or 4 = association plausible but not published for farmworkers. Of more than 80 studies we identified, only a third used environmental or biomarker evidence to document farmworker exposure to pesticides. Summaries of articles were compiled by level of evidence and presented in tabular form. A minimum list of data to be collected in farmworker pesticide studies was derived from these evidence tables. Despite ongoing concern about pesticide exposure of farmworkers and their families, relatively few studies have tried to test directly the association of behavioral and environmental factors with pesticide exposure in this population. Future studies should attempt to use similar behavioral, environmental, and psychosocial measures to build a body of evidence with which to better understand the risk factors for pesticide exposure among farmworkers. Key words: agricultural workers, folk belief, personal protective equipment, psychosocial stressors, safety behavior. Environ Health Perspect 114:943-952 (2006). doi:10.1289/ehp.8529 available via http://dx.doi.org/ [Online 16 February 2006]

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Human exposure to the pesticides that exist in the home, workplace, and community is regulated by a variety of behaviors and environmental factors. While many of these factors are commonly accepted in research on farmworker health and form the basis of pesticide safety education, there has been no comprehensive review of the empirical evidence linking these factors to exposure or to the relationship of exposure and health. We focus on the measurement of behavioral and environmental factors important at the following two points in the pesticide and health relationship: a) those that predict pesticide exposure, including who is exposed and how he or she is exposed, and b) those that modify the absorbed dose of pesticides.

We based this review on the premise that such a compilation of data will allow scientists to identify factors that have been found to be associated with pesticide exposure and, perhaps more importantly, to identify the gaps in current knowledge of the pesticide and health relationship. To the extent that determinants of exposure can be assessed with comparable measures across studies, results of such studies can then be compared to provide better-grounded answers to questions on the health effects of pesticides.

In this article we present a model of the relationship between predictors of pesticide exposure among farmworkers and pesticide exposure on health outcomes. We identify comprehensively the range of factors that may be associated with pesticide exposure, and we distinguish those for which a firm relationship with farmworker exposure has been identified in the scientific literature and those for which the association can only be inferred from other data. We also suggest a minimum set of measures that are necessary to understand farmworker pesticide exposure.

Conceptual Model

This article is guided by a model (Figure 1) that contrasts the proximal and the distal determinants of pesticide exposure. Those determinants that are proximal to pesticide exposure--that is, the immediate determinants of exposure--are generally behaviors practiced either by farmworkers in the workplace or by farmworkers or their co-resident household members at home. These determinants include (in the workplace) use of personal protective equipment (PPE) and field sanitation, as well as (at home) laundry practices and child activity patterns. These proximal factors are themselves determined by predictors that are considered more distal to the exposure. These predictors include environmental conditions at work (e.g., safety training), at home (e.g., number of farmworkers in residence), and in the larger community (e.g., total farmland treated with pesticides). These environmental factors affect exposure through behavior; the association of environmental and behavioral factors is moderated by psychosocial factors, including the attitudes, values, beliefs, and knowledge held by farmworkers. For example, farmworker residences with a high residential density might be expected to store soiled work clothing that would present an exposure risk to household residents. This relationship could be positively influenced by beliefs that pesticides are harmless, or negatively influenced by knowledge of recommended laundry practices.

A portion of pesticides to which an individual is exposed is absorbed as the pesticide dose, and this dose can have health effects. According to the model, the amount absorbed is moderated by some of the workplace and household behaviors (e.g., hand washing by workers or household residents) as well as by other factors. The latter moderators include genetic factors, body size, and developmental status; these characteristics are not covered in this review.

Methods

This review focuses on the conceptual model (Figure 1) developed by the authors. Components of the model were expanded to produce a list of factors potentially related to pesticide exposure in farmworkers. These factors formed the search terms for our review of the literature that searched the PubMed, (http://www.ncbi.nlm.nih.gov/entrez/query.1fcgi?DB=pubmed); Science Citation Index and Social Science Citation Index (http://portal. isiknowledge.com/portal.cgi/wos?Init=Yes&SI D=D112jMPBmi56JK4eA1); PsycINFO (http://www.psycinfo.org/psychoinfo/); and AGRICOLA (http://agricola.nal.usda.gov/) databases. We restricted reviews to peer-reviewed publications from studies that involved primary data collection and that were published in 1990 or later. A few earlier studies were included for topics with little research coverage. Articles were graded by the type of evidence for the association of a particular risk factor with pesticide exposure, as follows: 1 = association demonstrated in farmworkers; 2 = association demonstrated in nonfarmworker sample; 3 = plausible association proposed for farmworkers; or 4 = association plausible but not published for farmworkers. To be classified as "1," the study participants had to be described as migrant or seasonal farmworkers. In most other cases the study participants were described as "growers," "farmers," or members of their families, and they were classified as nonfarmworkers. Study participants described as "applicators" were classified as nonfarmworkers. Summaries of articles were compiled by level of evidence and presented in tabular form. Because of space restrictions, only those articles graded "1" or "2" are presented here (Table 1). A minimum list of data to be collected in farmworker pesticide studies was derived from these evidence tables (Table 2).

Workplace Behaviors

Wearing PPE is one of the behaviors most widely assumed to protect workers from pesticide exposure. The label PPE can apply to everything from long-sleeve shirts to protective coveralls and respirators. Studies in the United States and abroad show that wearing PPE appropriate to the task results in lower exposure to pesticides (Table 1). Although the studies vary with regard to the types of chemicals investigated, the PPE tested (gloves, overalls), and the types of exposure measured [cholinesterase activity, skin wipes, organochlorine pesticide (OCP) serum levels], they all indicate that PPE is effective in reducing worker exposure to pesticides (Fenske et al. 1990; Gomes et al. 1999; Hernandez-Valero et al. 2001; Lander et al. 1991; Ohayo-Mitoko et al. 1999). Studies in farmers (Arbuckle et al. 2002) and applicators (Fenske et al. 2002a; Nigg et al. 1993) lend further support to the effectiveness of PPE, although they also indicate variations because of fabrics and clothing design. In general, fabric less capable of penetration and designs that cover the largest amount of skin provide the greatest protection from pesticide exposure for workers. Despite the indications of efficacy, studies (particularly of farmers and applicators) show that PPE is frequently not used (e.g., Perry et al. 2002).

Other worker behaviors have been suggested as ways to reduce pesticide exposure, and these alternatives are included as recommended practices in the U.S. Environmental Protection Agency Worker Protection Standard (WPS) training (U.S. Environmental Protection Agency 1992). These behaviors include washing hands in the field before eating and after mixing pesticides. The importance of such behavior is demonstrated by studies showing that pesticides can be transferred to the home via automobile (e.g., Curl et al. 2002; Thompson et al. 2003). Curwin et al. (2003) showed that farmworker hand levels of the OP acephate could be reduced 96% by handwashing.

Additional practices have been suggested to reduce exposure. These practices include wearing grower-provided uniforms and showering at the worksite before returning home. There have been no tests to determine if such workplace behaviors would reduce exposure of the farmworker or the farmworker family.

Farmworker children are sometimes taken to the fields either to work or because adequate child care is lacking (Cooper et al. 2001). Such practices are likely to be predictors of pesticide exposure. Hernandez-Valero et al. (2003) investigated the possible pathways of OCP exposure among 36 migrant farmworker children whose home base was Baytown, Texas. One-third of the children had previously conducted farmwork, and the farmwork duration significantly increased their exposure levels. Mandel et al. (2005) found that children of Minnesota growers often helped apply chemicals and, therefore, had levels of pesticide exposure closer to those of the parent who applied chemicals than to the other parent.

Household Behaviors

The application of residential pesticides in the home and yard has been investigated as a source of pesticide exposure among farmworkers and nonfarmworkers (Table 1). The collection of wipe (Quandt et al. 2004) or vacuum samples (Bradman et al. 1997), which allow direct identification of the type of pesticide found, has been used to link pesticides applied to worker dwellings to those pesticides detected. However, not all studies have had positive results (McCauley et al. 2001). Urinary metabolites of OP pesticides have also supported the link between residential pesticide application and worker exposure (Arcury et al. 2005).

Similar results have been found in nonfarmworker populations. Yard and garden pesticides were found to be transferred into homes by residents and by dogs (Lewis et al. 2001, Morgan et al. 2001; Nishioka et al. 2001). Use of OP pesticides in gardens is associated with metabolite levels in children (Fenske 2002b; Lu et al. 2001).

Several household sanitation behaviors are associated with farmworker pesticide exposure. Bradman et al. (1997) found that more frequent mopping and vacuuming was associated with lower pesticide recoveries in dust wipes. Arcury et al. (2005) suggested that having a vacuum cleaner was associated with lower levels of urinary OP metabolites.

A number of studies have documented the high potential for personal exposure to pesticides caused by waiting for extended periods before showering after work, not changing clothes immediately after work, and failure to separate work from household laundry (Alavanja et al. 1999; Curwin et al. 2002; Goldman et al. 2004). However, with the exception of McCauley et al. (2003), there is little direct evidence to support this association.

Work Environment

The organization of work is a subfield of occupational health that is concerned with the way that work processes are structured and managed. Organization of work investigators attend to such factors as the nature of the employment relationship (e.g., permanent versus contingent labor), job design (e.g., complexity of tasks and level of worker control), interpersonal elements of jobs (e.g., worker-supervisor relations), as well as such things as work schedules, job security, and communication with an employing organization. Although it has not been explicitly used in farmworker research, evidence suggests that several aspects of the way farm work is organized contribute to pesticide exposure (Marquart et al. 2003).

Several interrelated processes underlying the nature of the employment relationship suggest that pesticide exposure is likely to be greater among farmworkers in seasonal (e.g., workers with H2A visas) or day labor relationships in contrast to those in more "permanent" positions. Farmworkers in employment relationships that are more permanent may receive more effective safety training and more consistent reinforcement of safety behaviors than seasonal farmworkers or day-laborers. Researchers contend that workers in nonstandard employment relationships, such as seasonal workers or day-laborers, may be given tasks that place them at greater risk of becoming exposed to pesticides compared to permanent workers (Quinlan et al. 2001). Moreover, farmworkers in seasonal and day-labor arrangements may be less likely to request safety equipment or to report potential hazards to owners/operators out of fear that it may jeopardize future opportunities for work (Aronsson 1999; Aronsson et al. 2002; Quinlan et al. 2001). Despite the plausibility of several of these linkages, differences in pesticide exposure among farmworkers in different types of employment relationships have not been studied explicitly.

Different aspects of job design, or the tasks performed on a job and how they are performed, have been linked to pesticide exposure (Table 1). Tasks that are not regulated by the WPS can result in elevated pesticide exposure (Coronado et al. 2004). A great number of tasks or duties that put individuals in contact with pesticides or pesticide residues, such as self-service and repair of application equipment among applicators and a greater number of field activities among workers, are associated with more exposure (Alavanja et al. 1999; Hernandez-Valero et al. 2001). Environments that provide farmworkers with little control over how pesticides are applied (e.g., highexposure application methods), when pesticides are applied (e.g., avoiding windy days), and frequency of application are all associated with increased pesticide exposure among farmworkers (Mage et al. 2000; Martin et al. 2002; Mekonnen and Agonafir 2002). Similarly, environments that provide little personal control over protective behaviors, such as absence of well-maintained PPE or inability to wash or change clothes during the workday, contribute to elevated pesticide exposure (Alavanja et al. 1999; Arcury et al. 2002; Austin et al. 2001; Mekonnen and Agonafir 2002; Parrott et al. 1999).

Although there have been no explicit comparison studies, it is likely that different crops are associated with different levels of pesticide exposure because of the differences in tasks associated with crops. For example, some will involve greater hand labor for cultivation and harvest than others. It is likely that those requiring more hand labor will result in greater exposure.

Interpersonal elements of farm work also contribute to pesticide exposure. Better-quality relationships between workers and farmers/growers are important for identifying potential sources of pesticide exposure as well as for designing and implementing effective strategies for minimizing exposure (Grieshop et al. 1996). Communication difficulties caused by language differences between workers and farmers/growers contribute to greater pesticide exposure through less effective training (McCauley et al. 2002; Rao et al. 2004). Similarly, differences in belief systems about the risks of pesticide exposure and appropriate behaviors for minimizing risk can contribute to elevated exposure by undermining the effectiveness of training and safety programs (Arcury et al. 2001; Quandt et al. 1998; Rao et al. 2004). The psychological demands of the work environment can also contribute to lower adherence to safety regulations (Kidd et al. 1996; Thu 1998; Walter et al. 2002). Despite the strong suggested connection of these work environmental factors to pesticides, no studies have examined pesticide exposure and the organization of work, either in farmworkers or in other populations.

One of the major aspects of the work environment directly related to pesticide exposure is safety training for workers. Minimum content and standards for pesticide safety training are part of the WPS, which mandates training for field workers as well as for applicators. A number of studies have examined safety training in farmworkers, but none of these have examined the association of safety training with pesticide exposure. This work shows that many farmworkers fail to receive training as mandated (Arcury et al. 1999; Elmore and Arcury 2001; U.S. General Accounting Office 2000) but that the rates vary over time (Arcury et al. 2001). Salazar et al. (2004) found that even when safety training is presented, it is sometimes understood poorly because of language barriers. Research with applicators (Martinez et al. 2004) and farmers (Perry and Layde 2003) shows that safety training produces increased knowledge, but it does not necessarily result in appropriate safety behaviors.

Household Environment: Physical and Social

Proximity of dwellings to agricultural fields treated with pesticides has been suggested as a dwelling characteristic associated with exposure (Fenske et al. 2000). Studies of dust samples from farmworker residences support this suggestion, both in terms of concentrations of pesticides (McCauley et al. 2001) and in numbers of pesticides found in the home (Quandt et al. 2002, 2004). Curl et al. (2003) found no association between distance to field and levels of metabolites found in children's urine. However, these metabolite levels were associated with house dust concentrations, which, in turn, were associated with the dust in cars of farmworkers, thereby indicating a pathway from worksite to home. Among nonfarmworkers, distance from dwelling to fields was associated with concentrations in house dust (Fenske et al. 2002b; Lu et al. 2000). This linkage was reflected in higher urine concentrations of metabolites in some (Loewenherz et al. 1997) but not all (Fenske et al. 2002b) studies measuring urinary metabolites.

Various housing quality indicators have been linked to greater pesticide exposure for farmworker families. Older dwelling age (Bradman et al. 1997) and renting rather than owning (Arcury et al. 2005) have been examined. These studies were based on the belief that the greater age of a house as well as a history of different tenants might lead to the accumulation of larger amounts of pesticides, both simply as a matter of time and because there might be more opportunity for pest infestations to which pesticides are applied. Both of these measures have been linked to exposure. Quandt et al. (2004) used an interviewer's judgment of how difficult or easy a house was to clean, reasoning that houses more difficult to clean would have a less thorough elimination of pesticides. Cleaning difficulty was associated with greater pesticide exposure.

Several aspects of the household social environment related to household composition have been suggested as major influences on pesticide exposure at home. The logic is that more persons in the household, particularly more farmworkers, will increase the volume of take-home pesticides, and this situation might be most extreme in cases of crowding. The simplest measure, total household size, has been linked to pesticides in two studies of farmworkers (Arcury et al. 2005; McCauley et al. 2001). These findings are supported by the study of Goldman et al. (2004) of pesticide-related behaviors. They found that larger household size was associated with fewer in-home safety behaviors. McCauley et al. (2003), in a study of nonfarmworker agricultural households, found weak and nonsignificant associations between household size and OP residues. More specific measures of household social environment (number of adults and number of agricultural workers in the household) have been suggested. However, this association generally has been tested by comparing agricultural and nonagricultural households (Bradman et al. 1997; Lu et al. 2000; Simcox et al. 1995), not by looking at the variation in number of adults within farmworker homes. Exceptions are the work of Arcury et al. (2005) and Quandt et al. (2004), which compared nuclear family households with those that comprised other adult relatives or nonrelatives and appeared to find more pesticides in the latter. This finding may be caused by greater track-in of pesticides with more adults, or by culture-specific issues. The investigators found that women residing in farmworker homes reported difficulty in enforcing standards of household cleanliness when male in-laws lived with the family because gender roles limit the authority of women over the behavior of fathers-in-law and other relatives. Only two studies have used density or crowding (e.g., persons/room and persons/square foot) as measures of the household social environment. McCauley et al. (2001) found no association in homes of farmworkers, and only a slight association in homes of other agricultural workers (McCauley et al. 2003).

Community Environment

Several different measures have been used to associate overall use of pesticides in a community with exposure. None has focused specifically on farmworkers. Fenske et al. (2000) found that a majority of children in an agricultural region from both agricultural and nonagricultural families had urinary metabolites for OPs. Similar results were reported by Koch et al. (2002), who found no differences because of parental occupation or residential proximity to fields. Lee et al. (2002) measured airborne agricultural pesticides at monitoring stations in California communities. They found that the level of exposure exceeded reference values for noncancer health effects for half of the population.

In agricultural communities, historical use of some persistent pesticides may have led to long-term contamination of the soil. In areas where lead arsenate was used extensively, soil samples have demonstrated the persistence of arsenic (Wolz et al. 2003). DDT, an OCP, is still found in soil samples despite its having been removed from use decades ago (Miersma et al. 2003).

Factors Moderating Behavior and Environment

Psychosocial stressors. Two pathways have been proposed by which psychosocial stressors might lead to pesticide exposure of farmworkers or of growers (Figure 1). None of the studies of these stressors have actually measured pesticides, so no data have been gathered with which to validate these pathways. The first pathway is through stressors on the farmworkers, primarily the result of their social position as immigrants and the process of acculturation that they undergo. Vega et al. (1985) found that Mexican American farmworkers experience high levels of psychiatric symptoms. These symptoms are associated with limited social mobility, transience, poverty, discrimination, and a high rate of traumatic life events. These findings were supported by Hovey et al. (2002a, 2002b), who found that farmworkers suffer from high rates of anxiety. This anxiety, in turn, is associated with elevated acculturative stress, low self-esteem, ineffective social support, and lack of control over the migrant lifestyle. Looking specifically at female farmworkers, Carruth and Logan (2002) documented high levels of depressive symptoms, which were predicted by poor health, perceived hazards of farm work, having experienced recent farmwork-related injuries, and engaging in farm work over long periods of time. These documented stressors and associated mental health deficits may lead farmworkers to take more risks and to neglect to practice safety behaviors protective against pesticide exposure.

The second pathway is through stressors on growers and workers that result from the organization of farm work. Thu (1998) proposed that the narrow temporal window for growing and harvesting, long work hours in isolated work conditions, and the psychological stress associated with farming can push farmers to minimize safety standards. Others have argued that the psychological and physical demands of the job confronted by day-laborers, including farmworkers, directly promote accidents and injuries through fatigue and distraction (Kidd et al. 1996; Salazar et al. 2004; Thu 1998; Walter et al. 2002). They also argue that other difficulties faced by farmworkers, including economic hardship and job insecurity, further elevate the risk of exposure and exacerbate health effects of exposure because farmworkers who have few other employment options may fear requesting PPE or may work through dangerous situations.

Pesticide knowledge and beliefs. Farmworkers' knowledge about pesticides has generally been measured relative to prevailing scientific data, while beliefs come from more exploratory, ethnographic investigations. However, conceptually, both provide workers with information upon which they base their actions, so the distinction is somewhat artificial. Farmworker beliefs and knowledge have been collected in a number of studies that do not relate these data to pesticide exposure or to behaviors that might predict exposure. Quandt et al. (1998, 2001) identified several key beliefs held by farmworkers that might increase behaviors that would promote pesticide exposure. These beliefs include the ideas that pesticides must be felt, seen, tasted, or smelled to be present; the skin blocks absorption and body openings facilitate it; exposure occurs only when a pesticide is wet; susceptibility is individualized; and acute, not low-level chronic, exposure is the primary danger inherent in pesticide exposure. Elmore and Arcury (2001) found similar beliefs among Christmas tree workers. Salazar et al. (2004) found that workers expected to get sick as part of the job. They believed it was all right to work in unsafe conditions if the benefits were high enough. Hunt et al. (1999) found similar beliefs in southern Mexico.

In research with pesticide applicators, Martinez et al. (2004) found that applicators believe, in contrast to farmworkers, that dermal exposure is linked to long-term adverse health consequences, but not to acute illness. The knowledge and beliefs held by applicators reflect their participation in required training (Martinez et al. 2004; Perry et al. 2000). Much of it appears to have been learned by rote with less than optimal understanding of the health consequences of exposure.

Some studies have tried to measure the association of pesticide knowledge and beliefs with pesticide-related behavior. These studies (Arcury et al. 2002; Grieshop et al. 1996; McCauley et al. 2002; Vaughan 1993) show that greater knowledge of pesticide risks increases workers' sense of control and willingness to practice safety behaviors that should reduce exposure. Among farm operators, the belief that one had previously experienced adverse events of exposure was linked to taking greater precautions when working with pesticides (Lichtenberg et al. 1999).

Values and folk beliefs. Familism (an orientation to the welfare of one's immediate and extended family) has been noted as a strong value among Mexican and Central American immigrants (Romero et al. 2004; Sabogal et al. 1987; Salazar et al. 2004). Among adolescent farmworkers, this value is so strong that researchers (e.g., Salazar et al. 2004) have suggested that these workers are likely to neglect themselves (e.g., not adhere to safety practices) in their agricultural work with pesticides. Other authors (e.g., Romero et al. 2004; Sabogal et al. 1987) have suggested that familism should be associated with more positive health outcomes. Thus, of farmworkers who have been exposed to pesticides, those with greater familism may experience lower rates of pesticide-related illness.

Two folk illness concepts that are characteristic of Mexico have been identified among farmworkers. "Susto," an illness associated with having experienced a fright (Rubel 1984), was reported by a significant number of Mexican farmworkers in Florida who had experienced pesticide exposure (Baer et al. 1993). Arcury et al. (2001) reported that farmworkers expressed reluctance to use cold water for washing in the field and to shower immediately after returning home from work. They attributed this reluctance to a concern (indicative of a belief in humoral medicine) (Rubel 1960; Weller 1983) that their bodies were metaphorically hot from work and that the contact with water that, despite variation in temperature, is metaphorically cold, would result in rheumatism and other adverse health outcomes. These studies suggest that folk beliefs about the causes of illness can promote greater pesticide exposure by undermining protective behaviors such as hand washing and using PPE.

Summary of the Evidence

While many diverse factors have been proposed to have direct, indirect, or modifying effects on whether or not farmworkers are exposed to pesticides (Table 1; Figure 1), the research connecting characteristics of workers' environments and behaviors with actual measures of pesticide exposure is meager. Behavioral factors for which the best evidence of a direct relationship with pesticide exposure exists are use of PPE, use of pesticide products in and around the home, and personal hygiene behaviors such as hand washing at work and showering upon returning home from work.

Evidence of environmental factors associated with exposure is lacking for the occupational setting. Aside from clear evidence that job tasks that bring workers into contact with pesticides produce greater exposure, there has been little attempt actually to measure the effect of workplace safety training or the organization of work on exposure. Far more attention has been paid to the effects of the household environment of farmworkers and applicators on the exposure of workers and family members because we have better access to homes than to work sites. With some exceptions, research supports the link between proximity to fields and exposure. While studies use different measures, older houses of poorer quality appear to be linked to exposure. Similarly, different measures of household composition have been used. Most suggest that a greater number of adults and farmworkers in a house leads to greater amounts of pesticide in the dwelling and more pesticide exposure of the residents.

None of the psychosocial or cultural factors proposed as moderators in the association of environment or behavior with exposure has been examined with actual pesticide exposure data. Thus, the role of such factors in farmworker exposure is unknown.

The review of the evidence also highlights the fact that many of the existing studies that identify predictors of pesticide exposure in farmworkers, as well as in nonfarmworkers, have relied on self-reported behaviors rather than on true exposure measures. Among those studies that have included measures of exposure, some have employed environmental samples rather than biological measures. This history suggests that further studies of the association between predictors of exposure and actual biomarkers are warranted.

Recommendations for Data Collection and for Future Research

The evidence provided by this review, encompassing both factors with demonstrable links to exposure and those plausible but not well studied, indicates that a minimum set of concepts should be included in studies of farmworker pesticide exposure. The exact measures for each concept are not entirely clear because of the dearth of research that has actually sought to measure the association of predictors and exposure outcomes. Therefore, the recommendation is to obtain a broad enough group of measures to test for likely pathways of exposure.

This minimum set differs depending on whether the research focus is limited to occupational pesticide exposure of workers or if the focus includes the paraoccupational and environmental pesticide exposure of adults and children who reside with farmworkers. For the latter, some additional measures are included (e.g., child play areas). Measures are presented from proximal to distal determinants (Table 2). Although this review has included a variety of moderators that are likely to be important in the exposure pathway, there is currently insufficient research to recommend any particular set of such measures.

Future Research

This review suggests that a productive line of research would be to focus on the role of the organization of work with regard to pesticide exposure. This area of research can help identify aspects of the workplace that can be modified to protect workers from pesticide exposure. It is consistent with the approach of much of occupational safety and health, in that it relies less on changing human behavior directly than on "engineering" changes in work and the workplace environment. While the organization of work is a well developed area of research, it has not had widespread application to farmworker pesticide safety research.

The most obvious dearth of data found in this review is in the area of cultural and psychosocial factors that may moderate the effect of household and workplace environments on safety behaviors. Although such factors are clearly not direct influences on exposure, they condition the extent to which behavior or environmental change to protect workers and their families will be accepted, and they are, therefore, necessary components of behavioral interventions. It is premature to list specific data to be collected because such factors do not lend themselves to measurement through simple questions.

REFERENCES

Alavanja MC, Sandler DP, McDonnell CJ, Lynch CF, Pennybacker M, Zahn SH, et al. 1999. Characteristics of pesticide use in a pesticide applicator cohort: the Agricultural Health Study. Environ Res 80:172-179.

Arbuckle TE, Burnett R, Cole D, Teschke K, Dosemeci M, Bancej C, et al. 2002. Predictors of herbicide exposure in farm applicators. Int Arch Occup Environ Health 75:406-414.

Arcury TA, Quandt SA, Austin CK, Preisser J, Cabrera LF. 1999. Implementation of US EPA's Worker Protection Standard training for agricultural laborers: an evaluation using North Carolina data. Public Health Rep 114:459-468.

Arcury TA, Quandt SA, Cravey AJ, Elmore RC, Russell GB. 2001. Farmworker reports of pesticide safety and sanitation in the work environment. Am J Ind Med 39:487-498.

Arcury TA, Quandt SA, Rao P, Doran AM, Snively BM, Barr DB, et al. 2005. Organophosphate pesticide exposure in farmworker family members in western North Carolina and Virginia: case comparisons. Hum Organ 64:40-51.

Arcury TA, Quandt SA, Russell GB. 2002. Pesticide safety among farmworkers: perceived risk and perceived control as factors reflecting environmental justice. Environ Health Perspect 110:233-240.

Aronsson G. 1999. Contingent workers and health and safety. Work, Employment and Society 13:439-459.

Aronsson G, Gustafsson K, Dallner M. 2002. Work environment and health in different types of temporary jobs. Eur J Work Organ Psychol 11:151-175.

Austin C, Arcury TA, Quandt SA, Preisser JS, Saavedra RM, Cabrera LF. 2001. Training farmworkers about pesticide safety: issues of control. J Health Care Poor Underserved 12:236-249.

Baer R, Penzell D. 1993. Susto and pesticide poisoning among Florida farmworkers. Cult Med Psychiatry 17:321-327.

Bradman MA, Harnly ME, Draper W, Seidel S, Teran S, Wakeham D, et al. 1997. Pesticide exposures to children from California's Central Valley: results of a pilot study. J Expo Anal Environ Epidemiol 7:217-234.

Carruth AK, Logan CA. 2002. Depressive symptoms in farm women: effects of health status and farming lifestyle characteristics, behaviors, and beliefs. J Community Health. 27:213-228.

Cooper SP, Darrah AR, Vernon SW, Stallones L, MacNaughton N, Robison T, et al. 2001. Ascertainment of pesticide exposures of migrant and seasonal farmworker children: findings from focus groups. Am J Ind Med 40:531-537.

Coronado GD, Thompson B, Strong L, William CW, Islas I. 2004. Agricultural task and exposure to organophosphate pesticides among farmworkers. Environ Health Perspect 112:142-147.

Curl CL, Fenske RA, Elgethum K. 2003. Organophosphorus pesticide exposure of urban and suburban preschool children with organic and conventional diets. Environ Health Perspect 111:377-382.

Curl CL, Fenske RA, Kissel JC, Shirai JH, Moate TF, Griffith W, et al. 2002. Evaluation of take-home organophosphorus pesticide exposure among agricultural workers and their children. Environ Health Perspect 110:A787-792.

Curwin BD, Hein MJ, Sanderson WT, Nishioka M, Buhler W. 2003. Acephate exposure and decontamination on tobacco harvesters' hands. J Expo Anal Environ Epidemiol 13:203-210.

Curwin B, Sanderson W, Reynolds S, Hein M, Alavanja M. 2002. Pesticide use and practices in an Iowa farm family pesticide exposure study. J Agric Saf Health 8:423-433.

Elmore RC, Arcury TA. 2001. Pesticide exposure beliefs among Latino farmworkers in North Carolina's Christmas tree industry. Am J Ind Med 40:153-160.

Fenske RA, Birnbaum SG, Methner MM, Lu C, Nigg HN. 2002a. Fluorescent tracer evaluation of chemical protective clothing during pesticide applications in central Florida citrus groves. J Agric Saf Health 8:319-331.

Fenske RA, Blacker AM, Hamburger SJ, Simon GS. 1990. Worker exposure and protective clothing performance during manual seed treatment with lindane. Arch Environ Contam Toxicol 19:190-196.

Fenske RA, Kissel JC, Lu C, Kalman DA, Simcox NJ, Allen EH, et al. 2000. Biologically based pesticide dose estimates for children in an agricultural community. Environ Health Perspect 108:515-520.

Fenske RA, Lu C, Barr D, Needham L. 2002b. Children's exposure to chlorpyrifos and parathion in an agricultural community in central Washington state. Environ Health Perspect 110:549-553.

Goldman L, Eskenazi B, Bradman A, Jewell NP. 2004. Risk behaviors for pesticide exposure among pregnant women living in farmworker households in Salinas, California. Am J Ind Med 45:491-499.

Gomes J, Lloyd OL, Revitt DM. 1999. The influence of personal protection, environmental hygiene, and exposure to pesticides on the health of immigrant farm workers in a desert country. Int Arch Occup Environ Health 72:40-45.

Grieshop JI, Stiles MC, Villanueva N. 1996. Prevention and resiliency: A cross-cultural view of farmworkers' and farmers' beliefs about work safety. Hum Organ 55:25-32.

Hernandez-Valero MA, Bondy ML, Spitz MR, Zahm SH. 2001. Evaluation of Mexican American migrant farmworker work practices and organochlorine pesticide metabolites. Am J Ind Med 40:554-560.

Hernandez-Valero MA, Jones LA, Hajek RA. 2003. Potential pathways of exposure for DDE and mirex and reported health problems in Mexican-American migrant and seasonal farmworker children residing in Texas. J Children's Health 1:241-255.

Hovey JD, Magana CG. 2002a. Cognitive, affective, and physiological expressions of anxiety symptomatology among Mexican migrant farmworkers: predictors and generational differences. Commun Ment Health J 38:223-237.

Hovey JD, Magana CG. 2002b. Psychosocial predictors of anxiety among immigrant Mexican migrant farmworkers: implications for prevention and treatment. Cultur Divers Ethnic Minor Psychol 8:274-289.

Hunt LM, Tinoco-Ojanaguren R, Schwartz N, Halperin D. 1999. Balancing risks and resources: applying pesticides without using protective equipment in Southern Mexico. In: Anthropology in Public Health: Bridging Differences in Culture and Society (Hahn RA, Harris KW, eds). New York:Oxford University Press 235-254.

Kidd P, Scharf T, Veazie M. 1996. Linking stress and injury in the farming environment: a secondary analysis of qualitative data. Health Educ Q 23:224-237.

Koch D, Lu C, Fisker-Andersen J, Jolley, Fenske RA. 2002. Temporal association of children's pesticide exposure and agricultural spraying: report of a longitudinal biological monitoring study. Environ Health Perspect 110:829-833.

Lander F, Lings S. 1991. Variation in plasma cholinesterase activity among greenhouse workers, fruitgrowers, and slaughtermen. Br J Ind Med 48:164-166.

Lee S, McLaughlin R, Harnly M, Gunier R, Kreutzer. 2002. Community exposures to airborne agricultural pesticides in California: ranking of inhalation risks. Environ Health Perspect 110:1175-1184.

Lewis RG, Fortune CR, Blanchard FT, Camann DE. 2001. Movement and deposition of two organophosphorus pesticides within a residence after interior and exterior applications. J Air Waste Manage Assoc 51:339-351.

Lichtenberg E, Zimmerman R. 1999. Adverse health experiences, environmental attitudes, and pesticide usage behavior of farm operators. Risk Anal 19:283-294.

Loewenherz C, Fenske RA, Simcox NJ, Bellamy G, Kalman D. 1997. Biological monitoring of organophosphorus pesticide exposure among children of agricultural workers in central Washington state. Environ Health Perspect 105:1344-1353.

Lu C, Fenske RA, Simcox NJ, Kalman D. 2000. Pesticide exposure of children in an agricultural community: evidence of household proximity to farmland and take-home exposure pathways. Environ Res 84:290-302.

Lu C, Knutson DE, Fisker-Andersen J, Fenske RA. 2001. Biological monitoring survey of organophosphorus pesticide exposure among preschool children in the Seattle metropolitan area. Environ Health Perspect 109:299-303.

Mage DT, Alavanja MC, Sandler DP, McDonnell CJ, Kross B, Rowland A, et al. 2000. A model for predicting the frequency of high pesticide exposure events in the Agricultural Health Study. Environ Res 83:67-71.

Mandel JS, Alexander BH, Baker BA, Acquavella JF, Chapman P, Honeycutt R. 2005. Biomonitoring for farm families in the Farm Family Exposure Study. Scand J Work Environ Health 31(suppl 1):98-104.

Marquart J, Brouwer DH, Gijsbers JH, Links IH, Warren N, Van Hemmen JJ. 2003. Determinants of dermal exposure relevant for exposure modeling in regulatory risk assessment. Ann Occup Hyg 47:599-607.

Martin SA, Jr, Sandler DP, Harlow SD, Shore DL, Rowland AS, Alavanja MC. 2002. Pesticide use and pesticide-related symptoms among black farmers in the Agricultural Health Study. Am J Ind Med 41:202-209.

Martinez R, Gratton TB, Coggin C, Rene A, Waller W. 2004. A study of pesticide safety and health perceptions among pesticide applicators in Tarrant County, Texas. J Environ Health 66:34-37, 43.

McCauley LA, Lasarev MR, Higgins G, Rothlein J, Muniz J, Ebbert C, et al. 2001. Work characteristics and pesticide exposures among migrant agricultural families: a community-based research approach. Environ Health Perspect 109:533-538.

McCauley LA, Michaels S, Rothlein J, Muniz J, Lasarev M, Ebbert C. 2003. Pesticide exposure and self-reported home hygiene: practices in agricultural families. AAOHN J 51:113-119.

McCauley LA, Sticker D, Bryan C, Lasarev MR, Scherer JA. 2002. Pesticide knowledge and risk perception among adolescent Latino farmworkers. J Agric Saf Health 8:397-409.

Mekonnen Y, Agonafir T. 2002. Pesticide sprayers' knowledge, attitude and practice of pesticide use on agricultural farms of Ethiopia. Occup Med (Lond) 52:311-315.

Miersma NA, Pepper CB, Anderson TA. 2003. Organochlorine pesticides in elementary school yards along the Texas-Mexico border. Environ Pollut 126:65-71.

Morgan MK, Stout DM, II, Wilson NK. 2001. Feasibility study of the potential for human exposure to pet-borne diazinon residues following lawn application. Bull Environ Contam Toxicol 66:295-300.

Nigg HN, Stamper JH, Easter E, DeJonge JO. 1993. Protection afforded greenhouse pesticide applicators by coveralls: a field test. Arch Environ Contam Toxicol 25:529-533.

Nishioka MG, Lewis RG, Brinkman MC, Burkholder HM, Hines CE, Menkedick JR. 2001. Distribution of 2,4-D in air and on surfaces inside residences after lawn applications: comparing exposure estimates from various media for young children. Environ Health Perspect 109:1185-1191.

Ohayo-Mitoko GJ, Kromhout H, Karumba PN, Boleij JS. 1999. Identification of determinants of pesticide exposure among Kenyan agricultural workers using empirical modeling. Ann Occup Hyg 43:519-525.

Parrott R, Wilson K, Buttram C, Jones K, Steiner C. 1999. Migrant farm workers' access to pesticide protection and information: Cultivando Buenos Habitos campaign development. J Health Commun 4:49-64.

Perry MJ, Layde PM. 2003. Farm pesticides: outcomes of a randomized controlled intervention to reduce risks. Am J Prev Med 24:310-315.

Perry MJ, Marbella A, Layde PM. 2000. Association of pesticide safety knowledge with beliefs and intentions among farm pesticide applicators. J Occup Environ Med 42:187-193.

Perry MJ, Marbella A, Layde PM. 2002. Compliance with required pesticide-specific protective equipment use. Am J Ind Med 41:70-73.

Quandt SA, Arcury TA, Austin CK, Cabrera LF. 2001. Preventing occupational exposure to pesticides: using participatory research with Latino farmworkers to develop an intervention. J Immigr Health 3:85-96

Quandt SA, Arcury TA, Austin CK, Saavedra R. 1998. Farmworker and farmer perceptions of farmworker agricultural chemical exposure in North Carolina. Hum Organ 57:359-368.

Quandt SA, Arcury TA, Mellen, BG, Rao P, Camann DE, Doran AM, et al. 2002. Pesticides in wipes from farmworker residences in North Carolina. In: Proceedings of the 9th International Conference on Indoor Air Quality and Climate, 30 June-5 July 2002, Monterrey, CA (Levin H, ed). Santa Cruz, CA:Indoor Air 2002, 900-905.

Quandt SA, Arcury TA, Rao P, Snively BM, Camann DE, Doran AM, et al. 2004. Agricultural and residential pesticides in wipe samples from farmworker family residences in North Carolina and Virginia. Environ Health Perspect 112:382-387.

Quinlan M, Mayhew C, Bohle P. 2001. The global expansion of precarious employment, work disorganization, and consequences for occupational health: placing the debate in a comparative historical context. Int J Health Serv 31:507-536.

Rao P, Arcury TA, Quandt SA, Doran A. 2004. North Carolina growers' and extension agents' perceptions of Latino farmworkers' pesticide exposure. Hum Organ 63:151-161.

Romero AJ, Robinson TN, Haydel KF, Mendoza F, Killen JD. 2004. Associations among familism, language preferences, and education in Mexican-American mothers and their children. J Dev Behav Pediatr 25:34-40.

Rubel AJ. 1960. Concepts of disease in Mexican-American culture. Am Anthropol 62:795-814.

Rubel AJ, O'Nell CW. 1984. Susto, a Folk Illness. Berkeley, CA:University of California Press.

Sabogal F, Marin G, Otero-Sabogal R, Marin BV, Perez-Stable E. 1987. Hispanic familism and acculturation: what changes and what doesn't? Hisp J Behav Sci 9:397-412.

Salazar MK, Napolitano M, Scherer JA, McCauley LA. 2004. Hispanic adolescent farmworkers' perceptions associated with pesticide exposure. West J Nurs Res 26:146-166.

Simcox NJ, Fenske RA, Wolz SA, Lee IC, Kalman DA. 1995. Pesticides in household dust and soil: exposure pathways for children of agricultural families. Environ Health Perspect 103:1126-1134.

Spencer JR, Sanborn JR, Hernandez BZ, Krieger RI, Margetich SS, Schneider FA. 1995. Long vs. short monitoring intervals for peach harvesters exposed to foliar azinphos-methyl residues. Toxicol Lett 78:17-24.

Stehr-Green PA, Farrar JA, Burse VW, Royce WG, Wohlleb JC. 1988. A survey of measured levels and dietary sources of selected organochlorine pesticide residues and metabolites in human sera from a rural population. Am J Public Health 78:828-830.

Thompson B, Coronado GD, Grossman JE, Puschel K, Solomon CC, Islas I, et al. 2003. Pesticide take-home pathway among children of agricultural workers: study design, methods, and baseline findings. J Occup Environ Med 45:32-53.

Thu KM. 1998. The health consequences of industrialized agriculture for farmers in the United States. Hum Organ 57:335-341.

U.S. General Accounting Office. 2000. Pesticides: Improvements Needed to Ensure the Safety of Farmworkers and Their Children. GAO/RCED-00-40 Washington, DC:General Accounting Office.

U.S. Environmental Protection Agency. 1992. Pesticide Worker Protection Standard Training 40CFR Part 170.130.

Vaughan E. 1993. Chronic exposure to an environmental hazard: risk perceptions and self-protective behavior. Health Psychol 12:74-85.

Vega WA, Warheit G, Palacio R. 1985. Psychiatric symptomatology among Mexican American farmworkers. Soc Sci Med 20:39-45

Walter N, Bourgois P, Margarita Loinaz H, Schillinger D. 2002. Social context of work injury among undocumented day laborers in San Francisco. J Gen Intern Med 17:221-229.

Weller SC. 1983. New data on intracultural variability: the hot-cold concept of medicine and illness. Hum Organ 42:249-257.

Wolz S, Fenske RA, Simcox NJ, Palcisko, Kissel JC. 2003. Residential arsenic and lead levels in an agricultural community with a history of lead arsenate use. Environ Res 93:293-300.

Sara A. Quandt, (1) Maria A. Hernandez-Valero, (2) Joseph G. Grzywacz, (1) Joseph D. Hovey, (3) Melissa Gonzales, (4) and Thomas A. Arcury (1)

(1) Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA; (2) University of Texas, M.D. Anderson Cancer Center, Houston, Texas, USA; (3) University of Toledo, Toledo, Ohio, USA; (4) University of New Mexico, Albuquerque, New Mexico, USA

This article is part of the mini-monograph "Farmworker Exposure to Pesticides: Methodological Issues for the Collection of Comparable Data."

Address correspondence to S.A. Quandt, Division of Public Health Sciences, Dept. of Epidemiology and Prevention, Wake Forest University School of Medicine, Medical Center Blvd., Winston-Salem, NC 27157-1063 USA. Telephone: (336) 716-6015. Fax: (336) 713-4157. E-mail: squandt@wfubmc.edu

This article was produced as part of the Farmworker Environmental Health Research Comparable Data Conference held in Winston-Salem, NC, on 30 September-1 October 2004.

Financial support was provided by the Pesticide Environmental Trust Fund, N.C. Department of Agriculture and Consumer Services; the National Institute of Environmental Health Sciences (NIEHS) and the National Institute for Occupational Safety and Health (R13 ES/OH013378); and CropLife America, Inc. This work was supported in part by the intramural research program of the NIEHS, National Institutes of Health.

The authors declare they have no competing financial interests.

Received 11 July 2005; accepted 3 November 2005.
Table 1. Review of literature on predictors of pesticide exposure among
migrant and seasonal farmworkers.

 Relationship to pesticide exposure
Characteristic Rating (a) Reference Population

Workplace behaviors
 Availability and 1 Fenske et al. 12 farmworkers
 use of personal 1990
 protective
 equipment 1 Gomes et al. 532 farmworkers in
 1999 United Arab
 Emirates
 1 Lander et al. 100 greenhouse
 1991 workers and 43
 fruit growers;
 113 slaughtermen
 served as
 controls
 1 Ohayo-Mitoko 539 agricultural
 et al. 1999 workers in 4
 areas of Kenya
 1 Spencer et al. 28 peach
 1995 harvesters,
 California
 1 Hernandez-Valero 26 Mexican
 et al. 2001 American migrant
 farmworkers in
 Baytown, Texas
 2 Arbuckle et al. 126 pesticide
 2002 applicators in
 Ontario
 2 Fenske et al. 6 pesticide
 2002a applicators in
 central Florida
 citrus groves
 2 Nigg et al. 1993 3 greenhouse
 pesticide
 applicators in
 Florida
Field sanitation 1 Curwin et al. 12 Hispanic male
 2003 tobacco
 harvesters near
 Kinston, North
 Carolina
Household behaviors
 Residental 1 Arcury et al. 9 Latino
 pesticide use 2005 farmworker
 family
 households in
 western North
 Carolina and
 Virginia
 1 Bradman et al. 5 farmworker and
 1997 6 nonfarmworker
 dwellings in
 California's
 Central Valley
 1 McCauley et al. 96 farmworker
 2001 homes and 24
 grower homes in
 two agricultural
 communities in
 Oregon
 1 Quandt et al. 41 farmworker in
 2002, 2004 family homes
 North Carolina
 and Virginia
 2 Fenske et al. 12 farmworker
 2002b homes in Central
 Washington
 State; 14
 non-agricultural
 reference homes
 2 Lewis et al. 2001 Single household
 2 Lu et al. 2001 110 children, ages
 2-5 years, from
 96 households in
 the Seattle
 metropolitan area
 2 McCauley et al. 24 agricultural
 2003 families in
 northwestern US
 2 Morgan et al. Single family
 2001 dwelling in
 Chatham County,
 North Carolina
 2 Nishioka et al. 11 occupied and 2
 2001 unoccupied homes
Cleaning 1 Arcury et al. 9 Latino
 2005 farmworker
 family
 households in
 western North
 Carolina and
 Virginia
 1 Bradman et al. 5 farmworker and
 1997 6 nonfarm-
 workers
 dwellings in
 California's
 Central Valley
Laundry 1 Arcury et al. 9 Latino
 2005 farmworker
 family
 households in
 western North
 Carolina and
 Virginia
Delay changing 1 Arcury et al. 9 Latino
clothes and 2005 farmworker
bathing family
 households in
 western North
 Carolina and
 Virginia
 2 McCauley et al. 24 agricultural
 2003 families in
 northwestern US
Household pets 2 Lu et al. 2001 110 children, ages
 2-5 years, from
 96 households in
 the Seattle
 metropolitan area
 2 McCauley et al. 24 agricultural
 2003 families in
 northwestern US
 2 Morgan et al. Single-family
 2001 dwelling in
 Chatham County,
 North Carolina
 2 Nishioka et al. 11 occupied and 2
 2001 unoccupied homes
Child activity 2 Morgan et al. Single-family
patterns 2001 dwelling in
 Chatham County,
 North Carolina
 2 Mandel et al. 95 farm families
 2005 (grower, spouse,
 and child) in
 Minnesota and
 South Carolina
Diet 2 Curl et al. 2003 39 preschool age
 children (18
 children with
 organic diets
 and 21 children
 with
 conventional
 diets) in
 Seattle,
 Washington
 2 Stehr-Green et al. 85 rural-dwelling
 1988 persons
Transportation 1 Curl et al. 2002 218 farmworker
 households in
 Washington State
 1 Thompson et al. 571 farmworkers in
 2003 the Lower Yakima
 Valley in
 Washington State
Workplace environment
Task variety 1 Hernandez-Valero 26 Mexican
 et al. 2001 American migrant
 farmworkers in
 Baytown, Texas
Job design 1 Coronado et al. 213 farmworkers in
 2004 24 communities
 and labor camps
 in eastern
 Washington State
Household environment: dwelling characteristics
Dwelling 1 McCauley et al. 96 farmworker
(location 2001 homes and 24
relative to grower homes in
exposure two agricultural
sources) communities in
 Oregon
 1 Curl et al. 2002 218 farmworker
 households in
 Washington State
 1 Quandt et al. 41 farmworker
 2002, 2004 family
 residences in
 North Carolina
 and Virginia
 2 Fenske et al. 12 farmworker
 2002b homes in Central
 Washington State
 and 14
 non-agricultural
 reference homes
 2 Loewenherz et al. 88 children under
 1997 6 years in 48
 pesticide
 applicator and
 14 reference
 families
 2 Lu et al. 2000 109 children, 9
 months to 6
 years, in an
 agricultural
 community in
 central
 Washington State
Dwelling type 1 McCauley et al. 96 farmworker
 2001 homes and 24
 grower homes in
 two agricultural
 communities in
 Oregon
Dwelling tenure 1 Arcury et al. 9 Latino
 2005 farmworker
 family
 households in
 western North
 Carolina and
 Virginia
Housing 1 Bradman et al. 5 farmworker and
quality/state 1997 6 nonfarmworker
of repair dwellings dwelling in
 California's
 Central Valley
 1 Quandt et al. 41 farmworker
 2002, 2004 family
 residences in
 North Carolina
 and Virginia
Household environment: household characteristics
Total household 1 Arcury et al. 9 Latino
size (total 2005 farmworker
number of family
residents) households in
 western North
 Carolina and
 Virginia
 1 McCauley et al. 96 farmworker
 2001 homes and 24
 grower homes in
 two agricultural
 communities in
 Oregon
 2 McCauley et al. 24 agricultural
 2003 families in
 northwestern
 United States
 1 Arcury et al. 9 Latino
 2005 farmworker
 family
 households in
 western North
 Carolina and
 Virginia
Number of 1 McCauley et al. 96 farmworker
farmworkers in 2001 homes and 24
household grower homes in
 two agricultural
 communities in
 Oregon
 1 Bradman et al. 5 farmworker and
 1997 6 nonfarm-
 workers
 dwellings in
 California's
 Central Valley
 2 Lu et al. 2000 109 children, 9
 months to 6 years
 of age, in an
 agricultural
 community in
 central
 Washington State
 2 Simcox et al. 26 farming, 22
 1995 farmworker, and
 11 nonfarming
 residences in
 eastern
 Washington State
Household 1 Arcury et al. 9 Latino
composition 2005 farmworker
 family
 households in
 western North
 Carolina and
 Virginia
 1 Quandt et al. 41 farmworker
 2004 family
 residences in
 North Carolina
 and Virginia
Household 1 McCauley et al. 96 farmworker
density or 2001 homes and 24
crowding grower homes in
 two agricultural
 communities in
 Oregon
 2 McCauley et al. 24 agricultural
 2003 families in
 northwestern
 United States
Community environment
 Overall level of 1-2 Fenske et al. 109 children in
 agricultural 2000 agricultural
 use community in
 eastern
 Washington State
 (91 had parents
 working
 agriculture)
 2 Koch et al. 2002 44 children living
 in an
 agricultural
 community in
 central
 Washington State
 2 Lee et al. 2002 California
 communities
Historical 2 Wolz et al. 2003 58 homes in
agricultural agricultural
pesticide use community in
 Washington State
 2 Miersma et al. Elementary school
 2003 yards in 8 cities
 near the Texas-
 Mexico border

 Relationship to pesticide exposure
Characteristic Reference Exposure measurement

Workplace behaviors
 Availability and Fenske et al. Dermal exposure to lindane
 use of personal 1990
 protective
 equipment Gomes et al. Blood sample:
 1999 Acetylcholinesterase (AChE)
 activity
 Lander et al. Blood sample: AChE activity
 1991
 Ohayo-Mitoko Blood sample: AChE activity
 et al. 1999
 Spencer et al. Dislodgeable foliar residue of
 1995 azinphos-methyl (AM)
 pesticides measured on skin
 and clothing
 Hernandez-Valero Blood samples: 21
 et al. 2001 organochlorine pesticides
 (OCPs)
 Arbuckle et al. Urine samples: Phenoxy-
 2002 herbicides 2,4-
 dichlorophenoxyacetic acid
 (2,4-D) or 4-chloro-2-
 methylphenoxyacetic acid
 (MCPA)
 Fenske et al. Exposure to organophosphorus
 2002a (OP) insecticide ethion
 during airblast application
 by fluorescent tracer
 deposition on skin surfaces
 beneath garments, video
 imaging analysis instrument
 (VITAE system), and alpha-
 cellulose patches placed
 outside and beneath the
 garments
 Nigg et al. 1993 Pads placed inside and outside
 three types of protective
 coveralls measured exposure
 to chlorpyrifos, fluvalinate,
 and ethazol
Field sanitation Curwin et al. Handwipes: acephate residues
 2003
Household behaviors
 Residental Arcury et al. Urine samples: OP metabolites
 pesticide use 2005
 Bradman et al. House dust and handwipe sample:
 1997 33 pesticides
 McCauley et al. House dust samples: residues of
 2001 major OPs used in area crops
 Quandt et al. Wipe samples from floor, toys,
 2002, 2004 and children's hands: 8
 locally reported agricultural
 pesticides and 13 pesticides
 commonly found in U.S. houses
 Fenske et al. House dust samples and
 2002b children's urine samples: 2
 diethyl OP pesticides--
 chlorpyrifos and parathion
 Lewis et al. 2001 Samples of indoor air;
 vacuumable carpet dust;
 carpet dislodgeable residues;
 deposits on bare floors,
 table tops, and dinnerware;
 surrogate food; and residues
 on children's hands and toys:
 diazinon and chlorpyrifos
 Lu et al. 2001 Urine samples: 6
 dialkylphosphate (DAP)
 compounds
 McCauley et al. House dust samples: OP
 2003 pesticides
 Morgan et al. Soil, turf, and carpet
 2001 samples; 24-hr air samples;
 handwipes; and samples taken
 from dog fur and paws
 Nishioka et al. Indoor air samples; surface
 2001 wipes from floors, table
 tops, and window sills; and
 floor dust samples before and
 after lawn application of the
 herbicide 2,4-D
Cleaning Arcury et al. Urine samples: OP metabolites
 2005
 Bradman et al. House dust and handwipe
 1997 samples: 33 pesticides
Laundry Arcury et al. Urine samples: OP metabolites
 2005
Delay changing Arcury et al. Urine samples: OP metabolites
clothes and 2005
bathing
 McCauley et al. House dust samples: OP
 2003 pesticides
Household pets Lu et al. 2001 Spot urine samples: six
 dialkylphosphate (DAP)
 compounds
 McCauley et al. House dust samples: OP
 2003 pesticides
 Morgan et al. Soil, turf, and carpet
 2001 samples; 24-hr air samples;
 handwipes; and samples taken
 from dog fur and paws:
 pesticides
 Nishioka et al. Indoor air samples; surface
 2001 wipes from floors, table
 tops, and window sills; and
 floor dust samples: before
 and after lawn application of
 herbicide 2,4-D
Child activity Morgan et al. Soil, turf, and carpet samples;
patterns 2001 24-hr air samples; handwipes,
 and samples taken from dog
 fur and paws: pesticides
 Mandel et al. 24-hr urine samples: 2,4-D;
 2005 glyphosphate; and metabolite
 of chlorpyrifos
Diet Curl et al. 2003 24-hr urine samples: 5 OP
 pesticide metabolites
 Stehr-Green et al. Blood samples: 11 pesticide
 1988 residues and metabolites
Transportation Curl et al. 2002 House and vehicle dust samples:
 6 pesticides
 Urine samples: 5-
 dialkylphosphate (DAP)
 metabolites
 Thompson et al. Urine samples of farmworkers
 2003 and children, house and
 vehicle dust samples:
 pesticides
Workplace environment
Task variety Hernandez-Valero Blood samples measured 21
 et al. 2001 organochlorine pesticides
 (OCPs)
Job design Coronado et al. Urine samples: OP metabolites;
 2004 House and vehicle dust
 samples: OP pesticides
Household environment: dwelling characteristics
Dwelling McCauley et al. Home dust samples: OP residues
(location 2001
relative to
exposure Curl et al. 2002 House and vehicle dust samples:
sources) 6 pesticides Urine samples: 5
 OP metabolites
 Quandt et al. Wipe samples from floor, toys,
 2002, 2004 and children's hands: 8 eight
 locally reported agricultural
 pesticides and 13 pesticides
 commonly found in U.S. houses
 Fenske et al. House dust samples and
 2002b children's urine samples:
 chlorpyrifos and parathion
 Loewenherz et al. Urine samples: OP metabolites
 1997
 Lu et al. 2000 Urine and hand wipe samples: OP
 pesticides
 House dust samples and wipe
 samples: OP pesticides
Dwelling type McCauley et al. Home dust samples: residues of
 2001 major OPs used in area crops
Dwelling tenure Arcury et al. Urine samples: OP metabolites
 2005
Housing Bradman et al. House dust and handwipe sample:
quality/state 1997 33 pesticides
of repair
 Quandt et al. Wipe samples from floor, toys,
 2002, 2004 and children's hands: 8
 locally reported agricultural
 pesticides and 13 pesticides
 commonly found in U.S. houses
Household environment: household characteristics
Total household Arcury et al. Urine samples: OP metabolites
size (total 2005
number of
residents) McCauley et al. Home dust samples: OP residues
 2001
 McCauley et al. House dust samples: OP
 2003 pesticides
 Arcury et al. Urine samples: OP metabolites
 2005
Number of McCauley et al. Home dust samples: OP residues
farmworkers in 2001
household
 Bradman et al. House dust and handwipe sample:
 1997 33 pesticides
 Lu et al. 2000 Urine and hand wipe samples: OP
 pesticides. House dust
 samples and wipe samples from
 various surfaces: OP
 pesticides
 Simcox et al. House dust and soil samples: 4
 1995 OP insecticides
Household Arcury et al. Urine samples: OP metabolites
composition 2005
 Quandt et al. Wipe samples from floor, toys,
 2004 and children's hands: 8
 locally reported agricultural
 pesticides and 13 pesticides
 commonly found in U.S. houses
Household McCauley et al. Home dust samples: OP residues
density or 2001
crowding
 McCauley et al. House dust samples: OP residues
 2003
Community environment
Overall level of Fenske et al. Urine samples: OP metabolites
agricultural 2000
use
 Koch et al. 2002 Urine samples: dialkylphosphate
 (DAP) metabolites
 Lee et al. 2002 Ambient air sampling of
 multiple classes of
 airborne pesticides
Historical Wolz et al. 2003 Soil and house dust samples:
agricultural lead arsenate
pesticide use
 Miersma et al. Soil samples: OCPs
 2003

 Relationship to pesticide exposure
Characteristic Reference Findings

Workplace behaviors
 Availability and Fenske et al. Demonstrated penetration of
 use of personal 1990 lindane through workshirt and
 protective pants. Recommended adding
 equipment coveralls and gauntlet-type
 gloves
 Gomes et al. Higher AChE was associated with
 1999 changing work clothes and use
 of work coveralls, gloves,
 and face scarf
 Lander et al. Wearing gloves was protective
 1991 of AChE activity in
 greenhouse workers
 Ohayo-Mitoko Use of coverall resulted in
 et al. 1999 less AChE inhibition than not
 wearing coverall or just
 wearing boots
 Spencer et al. More pesticides were found on
 1995 outer of two shirts,
 indicating the protective
 effect of clothing from
 dislodgeable residues
 Hernandez-Valero Wearing gloves and hats
 et al. 2001 resulted in less OCP exposure
 in farmworkers than wearing
 only hats
 Arbuckle et al. Reduced pesticide in urine
 2002 following application was
 associated with use of rubber
 gloves for mixing/loading,
 and wearing rubber boots for
 cleanup
 Fenske et al. Among applicators, compared
 2002a dermal exposure to pesticides
 for cotton work shirts/pants,
 woven coveralls, nonwoven
 garments. All garments
 allowed fabric penetration.
 Exposure was highest with
 nonwoven garments, mostly
 because of large sleeve and
 neck openings
 Nigg et al. 1993 Less penetration of synthetic
 disposable coverall than of
 reusable treated twill
 coverall
Field sanitation Curwin et al. Farmworkers removed 96% of
 2003 acephate on hands by washing
Household behaviors
 Residental Arcury et al. Residential pesticide use was
 pesticide use 2005 associated with higher levels
 of OP metabolites in samples
 from children and adults
 living in farmworker
 dwellings
 Bradman et al. Residential application of
 1997 agricultural and residential
 pesticides was related to
 presence of pesticides in
 dust samples
 McCauley et al. Found no relationship between
 2001 pesticides in wipe samples
 and "family use of pest
 control products"
 Quandt et al. Found a greater number and
 2002, 2004 weight of residential
 pesticides than agricultural
 pesticides in dust samples
 collected in farmworker
 dwellings
 Fenske et al. OP pesticide use in garden was
 2002b associated with increased
 metabolite concentrations in
 children's urine
 Lewis et al. 2001 Demonstrated that indoor and
 outdoor residential pesticide
 application resulted in
 pesticides on surfaces in
 homes accessible to human
 contact
 Lu et al. 2001 Children's OP pesticide
 concentrations were higher if
 parents reported garden
 pesticide use but were not
 based on indoor residential
 pesticide use
 McCauley et al. Pesticide use in the home was
 2003 not related to levels of
 total OP residues
 Morgan et al. Children and adults were
 2001 exposed to pesticides that
 were applied to yards and
 then were transferred into
 the house by pets (dogs),
 adults, and children
 Nishioka et al. Children and adults were
 2001 exposed to pesticides that
 were applied to yards and
 then were transferred into
 the house by pets (dogs) and
 adults
Cleaning Arcury et al. Living in a dwelling that is
 2005 easier to clean and that has
 a vacuum cleaner was
 associated with lower levels
 of OP metabolites among
 children and adults
 Bradman et al. Frequency and type of cleaning
 1997 (mopping, vacuuming) was
 related to presence of
 pesticides in dust samples
Laundry Arcury et al. Higher levels of OP metabolites
 2005 for adults and children were
 associated with improper
 handling of laundry,
 including storage of work
 clothes in house and
 laundering of work clothes
 with family clothes
Delay changing Arcury et al. Higher levels of OP metabolites
clothes and 2005 for adults and children were
bathing associated with farmworkers
 who delay changing from work
 clothes and bathing
 McCauley et al. Level of total OPs and of
 2003 azinphos-methyl was higher
 in homes where workers waited
 > 2 hr before changing out of
 work clothes
Household pets Lu et al. 2001 OP pesticide concentrations in
 children were not different
 based on reported pet
 treatment
 McCauley et al. Total number of pets in the
 2003 home was not related to
 levels of total OP residues
 Morgan et al. Pet dog was a vehicle for the
 2001 transfer of pesticide
 residues from lawn to house
 Nishioka et al. Pet dog was a vehicle for the
 2001 transfer of pesticide
 residues from lawn to house
Child activity Morgan et al. Children were a vehicle for the
patterns 2001 transfer of pesticide
 residues from lawn to house
 Mandel et al. Children's urine pesticide
 2005 concentrations were lower
 than those of growers, but
 higher than those of growers'
 spouses, thus reflecting
 children's activity patterns
Diet Curl et al. 2003 Urine of children who ate an
 organic diet contained
 significantly lower levels of
 OP metabolites than urine of
 those who ate a conventional
 diet
 Stehr-Green et al. In "rural-dwelling persons,"
 1988 consumption of home-produced
 eggs and root vegetables was
 associated with increased
 serum concentrations of
 pesticides
Transportation Curl et al. 2002 Found pesticides in dust
 samples collected in
 farmworker vehicles
 Thompson et al. Found pesticides in dust
 2003 samples collected in
 farmworker vehcles
Workplace environment
Task variety Hernandez-Valero Number of tasks that brought
 et al. 2001 farmworkers into contact with
 pesticides was associated
 with elevated serum levels
 of mirex, DDT, and
 trans-nonachlor
Job design Coronado et al. Workers performing tasks not
 2004 regulated by WPS (e.g.,
 thinning) were more likely
 to have detectable levels of
 azinphos-methyl in house and
 vehicle dust
Household environment: dwelling characteristics
Dwelling McCauley et al. Found that azinphos-methyl
(location 2001 concentration decreased with
relative to increased distance from
exposure fields
sources) Curl et al. 2002 Strong correlation between
 pesticides in cars and in
 house dust. Weaker
 correlation between house
 dust and child urine. No
 association between distance
 to fields and child's urine,
 thus suggesting that
 behavior, not proximity to
 fields, was responsible for
 exposure
 Quandt et al. Proximity to agricultural
 2002, 2004 fields was related to the
 number of agricultural
 pesticides detected in dust
 samples collected in
 dwellings
 Fenske et al. Homes in close proximity (200
 2002b ft/60 m) to pesticide-treated
 farmland had higher
 chlorpyrifos and parathion
 house dust concentrations
 than did homes farther away,
 but this effect was not
 reflected in the urinary
 metabolite data
 Loewenherz et al. Higher DMTP levels were found
 1997 in applicator children living
 < 200 ft from an orchard than
 in nonproximal applicator
 children
 Lu et al. 2000 Higher levels of pesticides
 were found in dust samples
 from dwellings closer to
 orchards
Dwelling type McCauley et al. Housing type (labor camp,
 2001 trailer, apartment) was not
 related to pesticide residues
Dwelling tenure Arcury et al. Renting rather than owning was
 2005 associated with higher levels
 of OP metabolites found in
 samples from persons living
 in farmworker dwellings
Housing Bradman et al. Dwelling age is related to
quality/state 1997 presence of pesticides
of repair
 Quandt et al. More residential pesticides
 2002, 2004 were found in dust samples
 collected in dwellings judged
 to be difficult to clean
Household environment: household characteristics
Total household Arcury et al. Larger household size was
size (total 2005 associated with higher
number of levels of OP metabolites for
residents) adults and children
 McCauley et al. More persons in household was
 2001 related to greater
 azinphos-methyl in dust
 McCauley et al. Weak, nonsignificant
 2003 correlation was found
 between number of household
 residents and levels of total
 OP residues. Number of adults
 in household
 Arcury et al. More adults in the household
 2005 was associated with higher
 levels of OP metabolites for
 adults and children
Number of McCauley et al. More farmworkers in household
farmworkers in 2001 was related to greater
household azinphos-methyl in dust
 Bradman et al. Higher amounts of pesticides in
 1997 dust in farm worker than
 nonfarmworker homes.
 Pesticides found on hands of
 children in farmworker, but
 not nonfarmworker homes,
 suggest take home pesticides
 Lu et al. 2000 Households with agricultural
 workers had higher levels of
 OP pesticides in dust wipe
 samples and on children's
 hands, and higher levels of
 metabolites in children's
 urine samples, than reference
 homes
 Simcox et al. OP pesticide residues were
 1995 found more often in homes of
 agricultural workers than in
 reference homes
Household Arcury et al. Higher levels of OP metabolites
composition 2005 for adults and children were
 associated with nonnuclear
 family household composition
 Quandt et al. Nonnuclear family household
 2004 composition was weakly
 associated with agricultural
 but not with residential
 pesticides
Household McCauley et al. Found no relationship between
density or 2001 pesticides and area of home
crowding
 McCauley et al. Weak correlation was found
 2003 between total area of home
 and levels of total OPs
 residues
Community environment
Overall level of Fenske et al. Most children living in an
agricultural 2000 agricultural region during
use the spray season had
 measureable
 dialkyphosphates, and a
 substantial fraction
 had doses > reference
 values for azinphos-methyl
 Koch et al. 2002 DAP metabolites were elevated
 when OP pesticides were
 sprayed in the region. No
 differences were found to be
 related to parental
 occupation or residential
 proximity to fields
 Lee et al. 2002 Exposure estimates
 [greater than or equal to]
 risk of noncancer health
 effects reference values
 occurred for 50% of exposed
 population for several
 pesticides
Historical Wolz et al. 2003 Dwellings near land used for
agricultural orchard production during
pesticide use 1905-1947 had significantly
 higher soil and household
 lead, and also higher soil
 arsenic than other homes
 Miersma et al. Attributed OCPs found in school
 2003 yards to historical
 agricultural activity

(a) 1 = Association with pesticide exposure was demonstrated in
farmworkers. 2 = Association with pesticide exposure was demonstrated in
nonfarmworker samples.

Table 2. Recommended measures of predictors of pesticide exposure among
migrant and seasonal farmworkers.

Workplace Wear clean clothes to work (frequency)
behaviors Wash hands at work (frequency)
 Use of personal protective equipment (type, frequency)
Household Residential use of pesticides (type, frequency), including
behaviors pet products
 Wear work clothes into dwelling
 Wear work shoes into dwelling
 Time to changing from work clothes after work
 Time to bathing after work
 Contact with others before changing clothes after work
 Contact with others before bathing after work
 Storage of soiled work clothes
 Laundry method (machine, hand)
 Separation of work and family clothes in laundry
 Child play areas (inside, outside)
Work Safety training (contents, quality)
environment Work task (fieldwork, mix and load, apply)
 Access to hygiene facilities
 Availability of personal protective equipment
 Ability to communicate with supervisor
Residential Location relative to pesticide application
environment Housing structure type
 Housing overall repair
 Housing size (area, rooms)
 Bathing facilities per resident
 Laundry facilities per resident
 Total number residents
 Total number of farmworkers
 Crowding; adult/room; workers/room; workers/sleeping room
Community Agricultural acreage
environment Volume pesticides applied/year
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Title Annotation:Mini-Monograph
Author:Arcury, Thomas A.
Publication:Environmental Health Perspectives
Date:Jun 1, 2006
Words:11482
Previous Article:Biomonitoring of exposure in farmworker studies.
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