Agricultural task and exposure to organophosphate pesticides among farmworkers

Application and demonstration of meso-activity exposure factors to advance estimates of incidental soil ingestion among agricultural workers

BACKGROUND

Soil is an understudied and underregulated pathway of chemical exposure, particularly for agricultural workers who cultivate food in soils. Little is known about how agricultural workers spend their time and how they may contact soil while growing food. Exposure factors are behavioral and environmental variables used in exposure estimation.

OBJECTIVES

Our study aimed to derive exposure factors describing how growers engage in different tasks and use those factors to advance the use of time-activity data to estimate soil ingestion exposures among agricultural workers.

METHODS

We administered a meso-activity-based, season-specific soil contact activity questionnaire to 38 fruit and vegetable growers. We asked growers to estimate the frequency and duration of six meso-activities and describe how they completed them. We used questionnaire data to derive exposure factors and estimate empirical and simulated exposures to a hypothetical contaminant in soil via incidental ingestion using daily, hourly, and hourly-task-specific ingestion rates.

RESULTS

We generated exposure factors characterizing the frequency and duration of six meso-activities by season, and self-reported soil contact, glove use, and handwashing practices by meso-activity and season. Seasonal average daily doses (ADDs) were similar across all three forms of ingestion rates. No consistent patterns regarding task-specific contributions to seasonal or annual ADDs were observed.

Examination of urinary pesticide concentrations, protective behaviors, and risk perceptions among Latino and Latina farmworkers in Southwestern Idaho

INTRODUCTION

Studies have documented high levels of pesticide exposure among men farmworkers; however, few have examined exposures or the experiences of women farmworkers. Data gaps also exist regarding farmworkers' perceived risk and control related to pesticides, information that is critical to develop protective interventions.

OBJECTIVE

We aimed to compare urinary pesticide biomarker concentrations between Latino and Latina farmworkers and examine associations with occupational characteristics, risk perceptions, perceived control, and protective behaviors.

METHODS

We enrolled a convenience sample of 62 farmworkers (30 men and 32 women) during the pesticide spray season from April-July 2022 in southwestern Idaho. Participants were asked to complete two visits within a seven-day period; at each visit, we collected a urine sample and administered a questionnaire assessing demographic and occupational information. Urine samples were composited and analyzed for 17 biomarkers of herbicides and of organophosphate (OP) and pyrethroid insecticides.

RESULTS

Ten pesticide biomarkers (TCPy, MDA, PNP, 3-PBA, 4-F-3-PBA, cis- and trans-DCCA, 2,4-D, Glyphosate, AMPA) were detected in >80% of samples. Men and women had similar urinary biomarker concentrations (p = 0.19-0.94); however, women worked significantly fewer hours than men (p = 0.01), wore similar or greater levels of Personal Protective Equipment (PPE), and were slightly more likely to report having experienced an Acute Pesticide Poisoning (26% of women vs. 14% of men; p = 0.25). We observed inconsistencies in risk perceptions, perceived control, and protective behaviors among men.

DISCUSSION

Our study is one the first to examine pesticide exposure and risk perceptions among a cohort of farmworkers balanced on gender. Taken with previous findings, our results suggest that factors such as job tasks, biological susceptibility, or access to trainings and protective equipment might uniquely impact women farmworkers' exposure and/or vulnerability to pesticides. Women represent an increasing proportion of the agricultural workforce, and larger studies are needed to disentangle these findings.

Research on knowledge construction and analysis of pesticide exposure to children based on bibliometrics

Pesticide exposure is a major health problem that cannot be ignored, and children are particularly vulnerable and sensitive. As a result, the study of health damage in children caused by pesticide exposure has gradually developed into an important cross-disciplinary research topic. In this study, we reviewed the current state, characteristics, and trends of existing research findings and summarized them comprehensively and systematically through bibliometrics. We collected and examined a large number of studies using Citespace and Vosviewer, employing a clustering method to analyze the effects of pesticide exposure on children and to highlight the hot keywords in the research field. Through an analysis of the active time of high-frequency keywords, we found that the research field is in a hot spot, and the occurrence value of keywords was used to judge the innovation of the research results, thereby highlighting the frontier and key directions of future research in this field. We conclude that in addition to core pesticides, children, exposure, and other malaria and polychlorinated biphenyls also appear as high-frequency keywords in the research field of pesticide exposure effects on children. The core issues of concern in this field include occupational pesticide exposure and childhood leukemia, history of pesticide exposure during pregnancy and childhood leukemia, environmental factors and dietary intake and organophosphorus pesticide exposure in children, and pyrethroid pesticide exposure and neurobehavioral development in children. Future research may focus on how to control the safe use of pesticides, quantitative research on pesticide hazards, and potential effects on children's health.

A qualitative characterization of meso-activity factors to estimate soil exposure for agricultural workers

BACKGROUND

Agricultural workers' exposure to soil contaminants is not well characterized. Activity pattern data are a useful exposure assessment tool to estimate extent of soil contact, though existing data do not sufficiently capture the range and magnitude of soil contact in the agricultural context.

OBJECTIVE

We introduce meso-activity, or specific tasks, to improve traditional activity pattern methodology. We propose a conceptual framework to organize the factors that may modify soil exposure and impact soil contact estimates within each meso-activity in agriculture. We build upon models from the US EPA to demonstrate an application of this framework to dose estimation.

METHODS

We conducted in-depth interviews with sixteen fruit and vegetable growers in Maryland to characterize factors that influence soil exposure in agriculture. For illustrative purposes, we demonstrate the application of the framework to translate our qualitative data into quantitative estimates of soil contact using US EPA models for ingestion and dermal exposure.

RESULTS

Growers discussed six tasks, or meso-activities, involving interaction with soil and described ten factors that may impact the frequency, duration and intensity of soil contact. We organized these factors into four categories (i.e., Environmental, Activity, Timing and Receptor; EAT-R) and developed a framework to improve agricultural exposure estimation and guide future research. Using information from the interviews, we estimated average daily doses for several agricultural exposure scenarios. We demonstrated how the integration of EAT-R qualitative factors into quantitative tools for exposure assessment produce more rigorous estimates of exposure that better capture the true variability in agricultural work.

SIGNIFICANCE

Our study demonstrates how a meso-activity-centered framework can be used to refine estimates of exposure for agricultural workers. This framework will support the improvement of indirect exposure assessment tools (e.g., surveys and questionnaires) and inform more comprehensive and appropriate direct observation approaches to derive quantitative estimations of soil exposure.

IMPACT STATEMENT

We propose a novel classification of activity pattern data that links macro and micro-activities through the quantification and characterization of meso-activities and demonstrate how the application of our qualitative framework improves soil exposure estimation for agricultural workers. These methodological advances may inform a more rigorous approach to the evaluation of pesticide and other chemical and biological exposures incurred by persons engaged in the cultivation of agricultural commodities in soil.

Excretion time courses of lambda-cyhalothrin metabolites in the urine of strawberry farmworkers and effect of coexposure with captan

There are limited literature data on the impact of coexposure on the toxicokinetics of pesticides in agricultural workers. Using the largely employed pyrethroid lambda-cyhalothrin (LCT) and fungicide captan as sentinel pesticides, we compared individual temporal profiles of biomarkers of exposure to LCT in strawberry field workers following an application episode of LCT alone or in coexposure with captan. Participants provided all urine voided over a 3-day period after an application of a pesticide formulation containing LCT alone (E1) or LCT mixed with captan (E2), and in some cases following re-entry in treated field (E3). Pyrethroid metabolites were measured in all urine samples, in particular 3-(2-chloro-3,3,3-trifluoroprop-1-en-1-yl)-2,2-dimethyl-cyclopropanecarboxylic acid (CFMP), 3-phenoxybenzoic acid (3-PBA), and 4-hydroxy-3-phenoxybenzoic acid (4-OH3PBA). There were no obvious differences in individual concentration-time profiles and cumulative excretion of metabolites (CFMP, 3-PBA, 4-OH3BPA) after exposure to LCT alone or in combination with captan. For most workers and exposure scenarios, CFMP was the main metabolite excreted, but time courses of CFMP in urine did not always follow that of 3-PBA and 4-OH3BPA. Given that the latter metabolites are common to other pyrethroids, this suggests that some workers were coexposed to pyrethroids other than LCT. For several workers and exposure scenarios E1 and E2, values of CFMP increased in the hours following spraying. However, for many pesticide operators, other peaks of CFMP were observed at later times, indicating that tasks other than spraying of LCT-containing formulations contributed to this increased exposure. These tasks were mainly handling/cleaning of equipment used for spraying (tractor or sprayer) or work/inspection in LCT-treated field according to questionnaire responses. Overall, this study provided novel excretion time course data for LCT metabolites valuable for interpretation of biomonitoring data in workers, but also showed that coexposure was not a major determinant of variability in exposure biomarker levels. Our analysis also pointed out the importance of measuring specific metabolites.

Domestic use of pesticides during early periods of development and risk of testicular germ cell tumors in adulthood: a French nationwide case-control study

BACKGROUND

Testicular germ cell tumours (TGCT) are the most frequent cancers in young men in developed countries and their incidence rate has doubled worldwide over the past 40 years. Early life exposures to pesticides are suspected to increase TGCT risk. Our research aimed at estimating adult TGCT risk associated with parental domestic use of pesticides during early periods of child development.

METHODS

We conducted a case-control study of 304 TGCT cases, aged 18-45 years old, recruited in 20 French university hospitals, and 274 controls frequency-matched on hospital and birth year. Participants' mothers provided information on their domestic use of pesticides from 1 year before start of pregnancy to 1 year after their son's birth, for gardening activities, treatment of indoor plants, pets, wood and mold, and pest control. Odds ratios (OR) for TGCT (overall and by histological subtype) and 95% confidence intervals (CI) were estimated using conditional logistic regression.

RESULTS

Prevalence of reported domestic use of pesticides was 77.3% for insecticides, 15.9% for fungicides and 12.1% for herbicides. While no association was found for any use of insecticides (OR = 1.27, CI = 0.80-2.01) or herbicides (OR = 1.15, CI = 0.67-2.00), elevated risks of TGCT overall (OR = 1.73, CI = 1.04-2.87) and non-seminoma subtype (OR = 2.44, CI = 1.26-4.74) were observed for any use of fungicides. When specific purposes were examined, using fungicides and/or insecticides for woodwork (OR = 2.35, CI = 1.06-5.20) and using insecticides on cats and dogs (OR = 1.95, CI = 1.12-3.40) were associated with increased risk of non-seminoma subtype. We found no association for seminoma subtype.

CONCLUSIONS

Although recall bias may partially explain the elevated ORs, our study provides some evidence of a positive association between domestic use of pesticides during early periods of development, particularly fungicides and risk of adult TGCT and non-seminoma. Given the common domestic use of pesticides in France, further research on TGCT risk is warranted.

Pesticide exposure among Latinx child farmworkers in North Carolina

BACKGROUND

Although pesticides have adverse effects on child health and development, little research has examined pesticide exposure among child farmworkers. This analysis addresses two specific aims: (1) describes pesticide exposure among Latinx child farmworkers in North Carolina, and (2) delineates factors associated with this pesticide exposure.

METHODS

In 2018 (n = 173) and 2019 (n = 156) Latinx child farmworkers completed interviews and wore silicone wristbands for a single day to measure pesticide exposure. Wristbands were analyzed for 70 pesticides.

RESULTS

Most Latinx child farmworkers were exposed to multiple pesticides; the most frequent were pyrethroids (69.9% in 2018, 67.9% in 2019), organochlorines (51.4% in 2018, 55.1% in 2019), and organophosphates (51.4% in 2018, 34.0% in 2019). Children were exposed to a mean of 2.15 pesticide classes in 2018 and 1.91 in 2019, and to a mean of 4.06 pesticides in 2018 and 3.34 in 2019. Younger children (≤15 years) had more detections than older children; children not currently engaged in farm work had more detections than children currently engaged in farm work. Migrant child farmworkers had more detections than nonmigrants. For specific pesticides with at least 20 detections, detections and concentrations were generally greater among children not currently engaged in farm work than children currently engaged.

CONCLUSIONS

Children who live in farmworker communities are exposed to a plethora of pesticides. Although further research is needed to document the extent of pesticide exposure and its health consequences, sufficient information is available to inform the policy needed to eliminate this pesticide exposure in agricultural communities.

Estimating Exposure to Three Commonly Used, Potentially Carcinogenic Pesticides (Chlorolathonil, 2,4-D, and Glyphosate) Among Agricultural Workers in Canada

OBJECTIVES

Certain pesticides have been associated with adverse health outcomes including cancer and reproductive harms. However, little is known about the prevalence of occupational pesticide exposure among agricultural workers in Canada. The purpose of this study was to estimate the prevalence and likelihood of occupational exposure to pesticides in Canada's agricultural industry, using three commonly used, potentially carcinogenic pesticides [chlorothalonil, 2,4-dichlorophenoxyacetic acid (2,4-D), and glyphosate] as an example.

METHODS

Estimates were calculated using the Canadian Census of Population and the Census of Agriculture. The number of workers and the proportion of farms applying 'herbicides' or 'fungicides' by farm type was estimated using survey data from the Census of Agriculture. These values were multiplied to yield the potential number of workers at risk of exposure. Likelihood of exposure (i.e. exposed, probably exposed, and possibly exposed) was then qualitatively assigned using information on crop type, primary expected tasks, crop production practices, and residue transfer data. Additional agricultural workers who are at risk of exposure but not captured by the Census of Agriculture were identified using the 2016 Census of Population.

RESULTS

An estimated range of 37 700-55 800 workers (11-13% of agricultural workers) were exposed to glyphosate in Canada while 30 800-43 600 workers (9-11%) and 9000-14 100 (2.9-3.2%) were exposed to 2,4-D and chlorothalonil, respectively. Approximately 70-75% of workers at risk of exposure were considered probably or possibly exposed to any of the pesticides. Glyphosate exposure was most common among workers in oilseed (29% of oilseed farm workers exposed) and dry pea/bean farms (28%), along with those providing support activities for farms (31%). 2,4-D exposure was most common in corn (28%), other grain (28%), and soybean farms (27%), while chlorothalonil exposure was more likely among greenhouse, nursery, and floriculture workers (42%), workers on farms (28%, for occupations not captured by the Census of Agriculture, specifically), and those providing support activities for farms (20%). Regional variations broadly reflected differences in farm types by province.

CONCLUSIONS

This study estimated the prevalence of occupational exposure to three pesticides in Canada. Seasonal and temporary agricultural workers, which were captured by the Census of Agriculture, contributed to many additionally exposed workers. A large percent of the workers who were considered at risk of exposure were considered probably or possibly exposed, indicating a need for enhanced data collection and availability on pesticide use data in Canada. The study's methods can be applied to estimate workers' exposures to other pesticides within the agricultural industry.

Association between cholinesterase's inhibition and cognitive impairment: A basis for prevention policies of environmental pollution by organophosphate and carbamate pesticides in Chile

BACKGROUND

In Chile organophosphate pesticides are widely used in the production of fruits. Pesticides use is regulated for professional practice but there is no regulation regarding exposure to the general population.

OBJECTIVE

To relate exposure to cholinesterase's inhibitor pesticides during the spray season with neuropsychological impairment in occupationally exposed (OE) and environmentally exposed (EE) groups of people.

METHODS

Exposure was assessed through inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity and neuropsychological outcomes were evaluated through a large battery of tests covering general mental status, language, memory, attention, executive function, praxis and psychomotricity. Evaluations were carried out firstly in a period of no/low organophosphate pesticide use and subsequently during the spray season. All parameters were calculated as the relative change from baseline to spray season.

RESULTS

For this study in total 156 participants were recruited divided equally over participants with environmental exposures (EE) and participants with occupational exposure (OE). In the EE, BChE's enzyme activity inhibition ≥30% showed significant association with 10% or more decreased performance in several tests evaluating six of the eight cognitive areas (excepting psychomotricity and mood status); besides, for AChE inhibition in EE, the association was significant in three tests evaluating attention and one of executive function. Whereas, in OE, the inhibition of the BChE ≥30% was associated with a low performance of one attention test and for AChE the exceedance of the standard was associated with diminished performance in one test of memory and attention, respectively. The association between biomarkers of biological effect and cognitive impairment persisted among the EE group after removing confounders. No association was found between biomarkers of biological acute effect and decreased cognitive performance in the OE group.

CONCLUSIONS

Increased exposure to pesticides was confirmed by increased inhibition of cholinesterase's in both exposure groups; which was associated with a diminished neuropsychological performance, mainly in the environmentally exposed study group. [310 words].

Occupational Chemical Exposure and Breast Cancer Risk According to Hormone Receptor Status: A Systematic Review

Breast cancers include a heterogeneous group of diseases with clinical behaviors that may vary according to the hormonal receptor status. However, limited knowledge is available on the role of breast cancer environmental and occupational risk factors in the onset of specific molecular disease phenotypes. Therefore, the aim of this review was to provide an overview on the possible correlation between occupational chemical exposures and breast cancers with a specific receptor pattern. Pubmed, Scopus, and ISI Web of Science databases were systematically reviewed to identify all the studies addressing chemical exposure in workplaces and risk of breast cancer classified according to the presence of estrogen and/or progesterone receptors. Some positive associations were reported between solvent, polycyclic aromatic hydrocarbon, organophosphoric insecticide, and synthetic fiber exposure and estrogen receptor-positive cases, while other investigations demonstrated a relationship with receptor-negative tumors or failed to detect any significant effect. Overall, further investigation should overcome limitations due to the self-reported information on work histories, the chemical classification in general categories, and the lack of environmental or biological monitoring exposure data. This may support the development of suitable and individually "tailored" occupational risk assessment and management strategies to protect the health of exposed workers, particularly those with hypersusceptibility conditions.

Application of improved approach to evaluate a community intervention to reduce exposure of young children living in farmworker households to organophosphate pesticides

The take-home pathway is a significant source of organophosphate pesticide exposure for young children (3-5 years old) living with an adult farmworker. This avoidable exposure pathway is an important target for intervention. We selected 24 agricultural communities in the Yakima Valley of Washington State and randomly assigned them to receive an educational intervention (n = 12) to reduce children's pesticide exposure or usual care (n = 12). We assessed exposure to pesticides in nearly 200 adults and children during the pre and post-intervention periods by measuring metabolites in urine. We compared pre- and post-intervention exposures by expressing the child's pesticide metabolite concentration as a fraction of the adult's concentration living in the same household, because the amount of pesticides applied during the collection periods varied. Exposures in our community were consistently higher, sometimes above the 95^th percentile of the exposures reported by the National Health and Nutrition Examination Survey (NHANES). While intervention and control communities demonstrated a reduction in the ratio of child to adult exposure, this reduction was more pronounced in intervention communities (2.7-fold, p < 0.001 compared to 1.7-fold, p = 0.052 for intervention and control, respectively). By examining the child/adult biomarker ratio, we demonstrated that our community-based intervention was effective in reducing pesticide exposure to children in agricultural communities.

Evaluation of pelvic inflammatory disease potential in cholinesterase inhibitor pesticide-exposed females

Cholinesterase inhibitor pesticides, mainly organophosphates and carbamates, are commonly used in Egypt. Chronic exposure of males and females working in agriculture is expected. The study aimed to relate exposure to cholinesterase inhibitor pesticides to the development of pelvic inflammatory disease (PID). This is a case-control study that was conducted among 84 females. Seventy patients complained of pelvic inflammatory disease visited the outpatient Gynecology and Obstetrics Clinic. Fourteen females were not suffering from PID and were chosen as a control group. Red blood cells' cholinesterase activity was measured in blood. Cervical swaps were collected, and cultures were submitted for microbiological examination. The results showed that cholinesterase activities were significantly depressed in exposed females (6.36 ± 0.8 μmoles/min/ml red cells) when compared to non-exposed (7.5 ± 1.2 μmoles/min/ml red cells), and both were significantly depressed when compared with healthy females (9.17 ± 0.7 μmoles/min/ml red cells). The correlation coefficient (r) between previous exposure and the laboratory confirmed cervical infection was 0.31, with a P value of 0.009. The study concluded that exposure to cholinesterase inhibitor pesticides could increase the occurrence of pelvic inflammatory disease.

Subjective Symptoms of Male Workers Linked to Occupational Pesticide Exposure on Coffee Plantations in the Jarabacoa Region, Dominican Republic

Acute and sub-acute effects of pesticide use in coffee farmers have rarely been investigated. In the present field study, self-reported health symptoms from 38 male pesticide users were compared to those of 33 organic farmers. Results of cytological findings have been reported in an accompanying paper in this issue. The present second part of the study comprises a questionnaire based survey for various, potentially pesticide related symptoms among the coffee farmers. Symptom rates were generally higher in exposed workers, reaching significance in nine out of 19 assessed symptoms. Significantly increased symptom frequencies were related to neurotoxicity, parasympathic effects and acetylcholine esterase inhibition, with the highest differences found for excessive salivation, dizziness and stomach ache. We revealed a lack of precautionary measures in the majority of farmers. Better education, regulations, and safety equipment are urgently needed.

Disseminating Pesticide Exposure Results to Farmworker and Nonfarmworker Families in an Agricultural Community: A Community-Based Participatory Research Approach

OBJECTIVE

The aim of this study was to examine the impact of a dissemination process to provide individual pesticide results to study participants.

METHODS

After working with community members to disseminate data, 37 participants were recontacted via an interview survey to assess the effectiveness of the dissemination process.

RESULTS

Almost all participants (97.3%) recalled a home visit from a health promoter; 29 (78.4%) correctly recalled that the health promoter used a thermometer or graphic to explain the results; 26 (70.3%) correctly interpreted graphics showing high and low exposure levels in adults and 75.7% correctly interpreted results for children.

CONCLUSIONS

The study results support the use of a community-based participatory research approach to decide how to best depict and disseminate study results, especially among participants who are often left out of the dissemination process.

Mancozeb exposure results in manganese accumulation and Nrf2-related antioxidant responses in the brain of common carp Cyprinus carpio

Manganese (Mn)-containing dithiocarbamates such as Mancozeb (MZ) have been shown to induce oxidative stress-related toxicity in rodents and humans. However, little is known about the neurotoxic effects induced by MZ in fish. In this study, carp (Cyprinus carpio) were exposed to non-lethal waterborne concentrations of MZ, and oxidative stress parameters as well as metal accumulation in fish brains were evaluated. The experimental groups were as follows: control, MZ 5 mg/L, and MZ 10 mg/L. Fish were exposed for 7 days, and then brain was removed and prepared for subsequent analysis of antioxidant enzymes, reactive oxygen species (ROS), and expression of Nrf2 and phosphoNrf2. In parallel, manganese (Mn) levels were evaluated in blood and brain tissues. Mn levels were significantly increased in blood and brain of MZ-exposed carps. In addition, a concentration-dependent increase (p < 0.05) in ROS levels was observed in parallel to increments (p < 0.05) in the activity of major antioxidant enzymes, such as GPx, GR, and GST. On the other hand, significant decreases (p < 0.05) in CAT and SOD activities were observed. The expression of total and phosphorylated forms of Nrf2 was significantly (p < 0.05) upregulated in the brain of carps exposed to Mz when compared to the control, indicating an activation of the Nrf2 antioxidant pathway. Our study showed for the first time the activation of the Nrf2/ARE pathway and bioaccumulation of Mn induced by MZ exposure in fish species, highlighting important mechanisms of action and its toxicological impacts to aquatic organisms.

Organophosphate Pesticide Urinary Metabolites Among Latino Immigrants: North Carolina Farmworkers and Non-farmworkers Compared

BACKGROUND

This analysis documents detections and concentrations of the six dialkylphosphate (DAP) urinary metabolite of organophosphorus (OP) pesticides among North Carolina Latino migrant farmworkers, with comparison to non-farmworker Latino immigrants.

METHODS

Participants provided up to four urine samples during the 2012 and 2013 agricultural seasons. Composite urine samples for each year were analyzed.

RESULTS

DAP urinary metabolite detections were similar in farmworkers and non-farmworker; for example, for 2012, 75.4% of farmworkers and 67.4% of non-farmworkers and, for 2013, 89.3% of farmworkers and 89.7% of non-farmworkers had dimethylthiophosphate detections. DAP geometric mean concentrations were high; for example, dimethylphosphate concentrations among farmworkers were 11.39 μg/g creatinine for 2012 and 4.49 μg/g creatinine for 2013, while they were 10.49 μg/g creatinine for 2012 and 1.97 μg/g creatinine for 2013 for non-farmworkers CONCLUSIONS:: Research to reduce pesticide exposure among Latino farmworkers and non-farmworkers is needed.

Occupational predictors of urinary dialkyl phosphate concentrations in Mexican flower growers

Background Flower growers have high potential for exposures to pesticides. Occupational factors, such as tasks performed, the production method (organic or conventional), the use of personal protective equipment (PPE), and workplace characteristics influence the intensity of pesticide exposure. Objective To evaluate occupational characteristics affecting urinary concentration of dialkylphosphate (DAP) metabolites of organophosphate pesticides among a group of Mexican floricultural workers. Methods A questionnaire was administered to 117 workers who also provided a first morning urine sample. According to tasks performed and the production methods, pesticide contact was defined as low, medium, or high. PPE use was categorized as acceptable, fairly acceptable, and unacceptable. Urinary concentration of DAP metabolites were determined using gas-liquid chromatography. Association between occupational characteristics and DAP urinary concentrations was assessed by means of linear regression models. Results After adjusting for potential confounders, the workers in the medium and high contact categories had significantly higher DAP concentrations than those in the low contact category (β: 0.3, CI 95%: 0.1-0.5). Greenhouse workers had greater DAP concentrations than outdoors workers (β: 0.3, CI 95%: 0.1-0.5). Compared with non-acceptable use of PPE, acceptable use of PPE was associated with lower DAP concentrations (β: -0.4, CI 95% -0.6 to -0.1). Conclusion Improved safety training is needed for correct PPE usage, especially among flower growers who use conventional pest control methods and who work in a greenhouse environment.

Pesticide Urinary Metabolites Among Latina Farmworkers and Nonfarmworkers in North Carolina

OBJECTIVES

This paper compares detections and concentrations of pesticide urinary metabolites for Latina farmworkers and nonfarmworkers in North Carolina.

METHODS

Thirty-one farmworkers and 55 nonfarmworkers provided urine samples in 2012 and 2013. Urine samples were analyzed for detections and concentrations of organophosphate insecticide, bis-dithiocarbamate fungicide, and pyrethroid insecticide urinary metabolites.

RESULTS

Detections for several organophosphate and pyrethroid pesticide urinary metabolites were present for substantial proportions of the farmworkers and nonfarmworkers. Concentrations for several of these metabolites were high. Farmworkers and nonfarmworkers were similar in detections and concentrations for the pesticide urinary metabolites included in this analysis.

CONCLUSIONS

Participant pesticide exposure increases health risks for them and their children. Research needs to document pesticide exposure, its health effects, and ways to reduce it. Current information justifies policy development to reduce pesticide exposure in all communities.

Assessment of field re-entry exposure to pesticides: A dislodgeable foliar residue study

A dislodgeable foliar residue study was conducted in greenhouse pepper and tomato on the island of Crete, Greece, following the spray application of an SC insecticide (with active substance (a.s.) tebufenozide) and an EC fungicide (a.s. bupirimate). Furthermore, for the assessment of worker exposure to pesticides - as a result of re-entering the treated crops - a worker dermal exposure study was carried out during the tasks of tying or pruning, which allowed the transfer coefficient values for the specific tasks to be determined. Pesticide residues were analysed with an in house developed and fully validated HPLC-ESI/MS analytical method. The results from the study resulted in transfer coefficient values which were in agreement with current EFSA guideline values in most of the cases with the exception of bupirimate in a tomato greenhouse. In that case, high potential dermal exposure and low dislodgeable foliar residue values were observed, which is thought to be due to the moist leaves collected during sampling and monitoring, which led to greater than expected transfer coefficient values.

Organochlorine pesticides, their toxic effects on living organisms and their fate in the environment

Organochlorine (OC) pesticides are synthetic pesticides widely used all over the world. They belong to the group of chlorinated hydrocarbon derivatives, which have vast application in the chemical industry and in agriculture. These compounds are known for their high toxicity, slow degradation and bioaccumulation. Even though many of the compounds which belong to OC were banned in developed countries, the use of these agents has been rising. This concerns particularly abuse of these chemicals which is in practice across the continents. Though pesticides have been developed with the concept of target organism toxicity, often non-target species are affected badly by their application. The purpose of this review is to list the major classes of pesticides, to understand organochlorine pesticides based on their activity and persistence, and also to understand their biochemical toxicity.

Occupational hazards and health cost of women cotton pickers in Pakistani Punjab

Background

Farm workers and female cotton pickers are exposed to residual impacts of pesticide use in cotton production, in addition to dust, ultraviolet radiation, etc. Cotton picking causes various health hazards among cotton pickers with varied health cost. A soil bacterium known as Bacillus thuringiensis (Bt) is incorporated in cotton seed through genetic modification and it has resistance against certain bollworms of cotton. So it is considered that Bt cotton fields have less pesticide exposure compared to non-Bt cotton fields. This study was designed to examine and compare the impacts and health cost of cotton picking among female cotton pickers working in Bt and non-Bt cotton fields.

Methods

The study used the data collected from Vehari district of Pakistani Punjab. Health hazards and associated health cost of the respondents involved in Bt cotton picking were compared with those who harvested non-Bt cotton. Comparative use of the personal protective measures among those respondents was also examined. Health cost function and its determinants were analyzed using ordinary least square method.

Results

Findings of the study showed that 61 % cotton pickers from Bt cotton households reported one or more health effects of pesticide during picking season whereas this percentage for non-Bt cotton households was 66 %. Health impacts included skin problems, headache, cough, flu/fever, eye irritation and sleeplessness, however, percentage of these health impacts was comparatively higher among non-Bt cotton households. Health cost from exposure to pesticide use in cotton was US$ 5.74 and 2.91 per season for non-Bt cotton and Bt cotton households, respectively. Education, picking in Bt cotton fields and preventive measures were significantly related with health cost.

Conclusion

Cotton pickers working in Bt cotton fields are found to have less occupational health hazards compared to those working in non-Bt cotton fields. Thus generating awareness among cotton pickers for adopting precautionary measures during harvesting and the use of Bt cotton seed can result in a decline in the ill-effects of cotton picking.

Provision Increases Reported PPE Use for Mexican Immigrant Farmworkers: An mHealth Pilot Study

OBJECTIVE

Personal protective equipment (PPE) reduces pesticide exposures, but many farmworkers complain that it is difficult to obtain. We examined if PPE provision increased usage. We also delivered motivational messaging aimed to promote PPE use.

METHODS

First, we delivered a daily survey through a mobile phone app to assess PPE use. Farmworkers subsequently received a daily, individualized motivational message based on their PPE use and reported difficulties. PPE use was evaluated at baseline and at the close of the study.

RESULTS

PPE behaviors improved for gloves (P ≤ 0.01) and safety glasses (P ≤ 0.001). Use of long-sleeved shirts, hats, and long pants were already consistently used at baseline and did not exhibit significant change.

CONCLUSIONS

Our findings demonstrate that PPE provision and delivery of motivational messaging through mobile phones may increase PPE usage for farmworkers.

Brain Anatomy in Latino Farmworkers Exposed to Pesticides and Nicotine

OBJECTIVE

Migrant tobacco farmworkers experience regular occupational exposure to pesticides and nicotine. The present study was designed to determine whether there are differences in brain anatomy between Latino farmworkers and non-farmworkers.

METHODS

Magnetic resonance brain images were compared between farmworkers and non-farmworkers. In addition, blood cholinesterase activity and urinary cotinine levels were also used to identify associations with pesticide and nicotine exposure.

RESULTS

Farmworkers had greater gray matter signal in putamen and cerebellum, and lower gray matter signal in frontal and temporal lobes. Urinary cotinine was associated with the observed differences in brain anatomy, but blood cholinesterase activity was not.

CONCLUSIONS

Nicotine exposure was associated with neuroanatomical differences between Latino farmworkers and non-farmworkers. Future studies are needed to differentiate iron deposition from brain atrophy and to further assess the potential role of nicotine and pesticide exposure.

Organophosphate Pesticide Exposure Among Pome and Non-Pome Farmworkers: A Subgroup Analysis of a Community Randomized Trial

OBJECTIVE

We examined the effectiveness of a community randomized intervention among farmworkers who did and did not work in pome fruit (apples and pears).

METHODS

Urine samples were collected from two cross-sectional groups of farmworkers and analyzed for the presence of dimethylthiophosphate.

RESULTS

There was no significant time by crop interaction for changes in urinary metabolite concentrations among adult farmworkers (P = 0.79 pome fruit workers; P = 0.83 non-pome fruit workers) or their children (P = 0.25 children of pome fruit workers; P = 0.91 children of non-pome fruit workers). We found greater urinary metabolite concentrations of dimethylthiophosphate among pome fruit workers (compared with non-pome fruit workers) and among workers at final data collection (compared with baseline).

CONCLUSION

Further research is needed to identify effective interventions to reduce pesticide exposure in farmworkers and their children.

Farmers' Exposure to Pesticides: Toxicity Types and Ways of Prevention

Synthetic pesticides are extensively used in agriculture to control harmful pests and prevent crop yield losses or product damage. Because of high biological activity and, in certain cases, long persistence in the environment, pesticides may cause undesirable effects to human health and to the environment. Farmers are routinely exposed to high levels of pesticides, usually much greater than those of consumers. Farmers’ exposure mainly occurs during the preparation and application of the pesticide spray solutions and during the cleaning-up of spraying equipment. Farmers who mix, load, and spray pesticides can be exposed to these chemicals due to spills and splashes, direct spray contact as a result of faulty or missing protective equipment, or even drift. However, farmers can be also exposed to pesticides even when performing activities not directly related to pesticide use. Farmers who perform manual labor in areas treated with pesticides can face major exposure from direct spray, drift from neighboring fields, or by contact with pesticide residues on the crop or soil. This kind of exposure is often underestimated. The dermal and inhalation routes of entry are typically the most common routes of farmers’ exposure to pesticides. Dermal exposure during usual pesticide handling takes place in body areas that remain uncovered by protective clothing, such as the face and the hands. Farmers’ exposure to pesticides can be reduced through less use of pesticides and through the correct use of the appropriate type of personal protective equipment in all stages of pesticide handling.

Chronic exposure to organophosphate (OP) pesticides and neuropsychological functioning in farm workers: a review

BACKGROUND

Previous studies have demonstrated that acute poisoning from exposure to organophosphate (OP) pesticides in agricultural workers causes adverse health effects. However, neuropsychological and cognitive effects of chronic occupational exposure to OP pesticides remain controversial.

OBJECTIVE

To identify, evaluate, and systematize existing evidence regarding chronic exposure to OP pesticides and neuropsychological effects in farmworkers.

METHODS

Using the PubMed search engine, a systematic review process was implemented and replicated according to the PRISMA statement. Eligibility criteria included workers over 18 years of age exposed to OP pesticides as well as assessment of neuropsychological and cognitive functioning. Search terms were in English and Spanish languages and included organophosphate and workers.

RESULTS

Of the search results, 33 of 1,256 articles meet eligibility criteria. Twenty-four studies found an association between chronic occupational exposure to OP pesticides and low neuropsychological performance in workers. We classified nine of the studies to have study design limitations. Studies indicated occupational exposure to OP pesticides is linked to difficulties in executive functions, psychomotor speed, verbal, memory, attention, processing speed, visual-spatial functioning, and coordination. Nine studies find no relationship between OP pesticides exposure and neuropsychological performance.

CONCLUSIONS

Overall, evidence suggests an association between chronic occupational exposure to OP pesticides and neuropsychological effects. However, there is no consensus about the specific cognitive skills affected.

Home-based community health worker intervention to reduce pesticide exposures to farmworkers' children: A randomized-controlled trial

We conducted a randomized-controlled trial of a home-based intervention to reduce pesticide exposures to farmworkers' children in Monterey County, California (n=116 families). The intervention consisted of three home-based educational sessions delivered by community health workers in Spanish. Measurements of organophosphate (OP) insecticide metabolites in child urine (n=106) and pesticides in home floor wipes (n=103) were collected before and after the intervention. Median child urinary dialkyl phosphate (DAP) metabolite levels were slightly lower among the intervention group children at follow-up compared with baseline, albeit nonsignificantly. DAP metabolite levels in the control group children were markedly higher at follow-up compared with baseline. In adjusted models, intervention participation was associated with a 51% decrease in total DAP metabolite levels. Carbaryl, chlorpyrifos, cypermethrin, dacthal, diazinon, malathion, and trans-permethrin were commonly detected in the floor wipes. In adjusted models, intervention participation was significantly associated with a 37% decrease in trans-permethrin floor wipe levels in homes, but not OP or other agricultural pesticides. In summary, intervention group children had slightly reduced pesticide exposures, whereas child exposures were higher among the control group. Additional intervention studies evaluating methods to reduce pesticide exposures to farmworker families and children are needed.

Household pesticide exposure and the risk of childhood acute leukemia in Shanghai, China

Childhood acute leukemia (AL) is the most common malignant tumor in children, but its etiology remains largely unknown. We investigated the relationship between household exposure to pesticides and childhood AL. Between 2009 and 2010 in Shanghai, a total of 248 newly diagnosed cases of AL and 111 gender-, age-, and hospital-matched controls were included. Five nonspecific dialkyl phosphate (DAP) metabolites of organophosphate pesticides (OPPs) [including dimethyl phosphate (DMP), diethyl phosphate (DEP), dimethyl thiophosphate (DMTP), diethyl thiophosphate (DETP), and diethyl dithiophosphate (DEDTP)] in the urine were analyzed by gas chromatography. The results showed that the median DMP, DEP, DMTP, DETP, and DEDEP levels adjusted for creatinine (Cr) in cases (13.2, 10.0, 31.3, 8.5, and 6.1 μg g(-1), respectively) were all significantly elevated compared with those in controls (3.6, 3.6, 13.3, 2.7, and 1.7 μg g(-1), respectively) (P < 0.05). The household use of mosquito repellent was significantly associated with an increased risk of childhood AL (odds ratio (OR) = 1.9; 95% confidence interval (CI) 1.2-3.1). Moreover, higher exposures were significantly associated with an elevated risk of childhood AL for DMs, DEs, and DAPs. Our findings support the notion that the household use of pesticides may play a role in the etiology of childhood AL and provide some evidence to warrant further investigation of the link between household pesticide exposures and childhood AL in Shanghai.

A review of nonoccupational pathways for pesticide exposure in women living in agricultural areas

BACKGROUND

Women living in agricultural areas may experience high pesticide exposures compared with women in urban or suburban areas because of their proximity to farm activities.

OBJECTIVE

Our objective was to review the evidence in the published literature for the contribution of nonoccupational pathways of pesticide exposure in women living in North American agricultural areas.

METHODS

We evaluated the following nonoccupational exposure pathways: paraoccupational (i.e., take-home or bystander exposure), agricultural drift, residential pesticide use, and dietary ingestion. We also evaluated the role of hygiene factors (e.g., house cleaning, shoe removal).

RESULTS

Among 35 publications identified (published 1995-2013), several reported significant or suggestive (p < 0.1) associations between paraoccupational (n = 19) and agricultural drift (n = 10) pathways and pesticide dust or biomarker levels, and 3 observed that residential use was associated with pesticide concentrations in dust. The 4 studies related to ingestion reported low detection rates of most pesticides in water; additional studies are needed to draw conclusions about the importance of this pathway. Hygiene factors were not consistently linked to exposure among the 18 relevant publications identified.

CONCLUSIONS

Evidence supported the importance of paraoccupational, drift, and residential use pathways. Disentangling exposure pathways was difficult because agricultural populations are concurrently exposed to pesticides via multiple pathways. Most evidence was based on measurements of pesticides in residential dust, which are applicable to any household member and are not specific to women. An improved understanding of nonoccupational pesticide exposure pathways in women living in agricultural areas is critical for studying health effects in women and for designing effective exposure-reduction strategies.

Lifetime and current pesticide exposure among Latino farmworkers in comparison to other Latino immigrants

BACKGROUND

Pesticide exposure poses a health risk for farmworkers. This analysis documents lifetime and current pesticide exposure of North Carolina Latino migrant farmworkers, with comparison to non-farmworker Latino immigrants.

METHODS

During May to October 2012, 235 Latino farmworkers and 212 Latino non-farmworkers completed interviews with items to construct measures of lifetime, current residential and occupational pesticide exposure.

RESULTS

Farmworkers experience levels of lifetime and residential pesticide exposure that are consistently greater than among non-farmworkers. Farmworkers report a large number of occupational pesticide exposures. Lifetime exposure and current residential pesticide exposure are related to social determinants. Education is inversely related to lifetime pesticide exposure for farmworkers and non-farmworkers; farmworkers with H-2A visas report greater residential pesticide exposure than those without H-2A visas.

CONCLUSIONS

Occupational safety policy needs to consider these patterns of lifetime exposure when setting standards. Health care providers should be aware of the lifetime and current exposure of this vulnerable population.

Household and occupational exposure to pesticides and risk of breast cancer

The association between breast cancer in women and the use of household or occupational pesticides was examined in a population-based case-control study. This study was conducted in Western Australia in 2009-2011 and included 1,789 controls and 1,205 cases. Information on household pesticide exposure was collected from questionnaires. For occupational pesticide exposure, job-specific modules (JSMs) were used. To evaluate potential recall bias, we stratified the analysis by belief about whether pesticides contribute to breast cancer. Unconditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Women's exposures to pesticides in households and workplaces were not related to increased risk of breast cancer (OR = 1.10; CI: 0.86-1.37) and (OR = 0.77; CI: 0.45-1.32), respectively. The prevalence of occupational exposure to pesticides among women in our study was low. In the stratified analyses, the odd ratios associated with household pesticide use were similar among participants who believed pesticides increased breast cancer risk and those who did not. The results of our study did not show associations between breast cancer and household or occupational exposure to pesticides.

"I did it for us and I would do it again": perspectives of rural latinos on providing biospecimens for research

OBJECTIVES

We elicited perspectives of rural Latino farmworkers and non-farmworkers about their participation in a community-based participatory pesticides exposure study in which they provided multiple biospecimens.

METHODS

Between March and April 2012, we conducted semistructured, one-on-one interviews with 39 rural Latino farmworkers and non-farmworkers in Washington State (n = 39). Nineteen open-ended interview questions aimed to elicit participants' attitudes toward, expectations and experiences of biospecimen collection for research, and willingness to participate in future biomedical research studies. We reviewed and coded transcriptions using qualitative principles of grounded theory in which concepts were identified and themes derived from interview data.

RESULTS

We grouped themes into 3 major categories: (1) motivation to participate, (2) challenges of participation, and (3) perceived rewards of participation. Many participants were motivated by the perceived importance of the study topic and a desire to acquire and contribute to new knowledge. Respondents said that the benefits of participation outweighed the challenges, and many expressed satisfaction to be able to contribute to research that would benefit future generations.

CONCLUSIONS

Our findings supported the use of community-based participatory research to engage minorities as participants and invested parties in such studies.

Pesticides present in migrant farmworker housing in North Carolina

BACKGROUND

Migrant farmworkers are exposed to pesticides at work. Housing provided to migrant farmworkers may also expose them to pesticides, increasing their health risks. This analysis (1) describes the presence of organophosphorous (OP) and pyrethroid pesticides in North Carolina migrant farmworker houses, and (2) delineates associations of farmworker camp characteristics with pesticide detection and concentration.

METHODS

In 2010, 186 migrant farmworkers camps in NC were recruited (participation rate of 82.3%); pesticide wipe samples for 176 houses were analyzed. Tobacco is the predominant hand-harvested crop in this region. Two farmworkers per camp completed interviews; a third assisted with a housing inspection. Gas chromatography-mass spectrometry was used to detect OP and pyrethroid pesticides. Covariates of pesticide detection and concentration were determined with ANOVA and Tobit regression.

RESULTS

OPs were found in 166 of 176 houses (average of 2.4/house); pyrethroids were found in 171 houses (average of 4.3/house). The number of different OPs detected in each camp and concentrations of these OPs were not associated with camp and housing characteristics. The number of different pyrethroids detected in each camp and concentrations of these pyrethroids were associated with camps having residents with H2-A visas, a posted North Carolina Department of Labor Certificate of Inspection, no barracks, fewer residents, no bedroom weather protection or floor violations, and no roaches.

CONCLUSIONS

Farmworkers are exposed to pesticides where they live. Policy on removing pesticides from farmworker houses is needed. Reducing pesticides in farmworker houses will reduce one health risk confronted by this vulnerable population.

Health symptoms related to pesticide exposure and agricultural tasks among rice farmers from Northern Thailand

PURPOSE

The objective of this cross-sectional study was to investigate health symptoms related to occupational pesticide exposure and agricultural tasks in rice farmers.

METHODS

Data on demographic variables and health symptoms associated with pesticide exposure were collected from 182 rice farmers (exposed subjects) and 122 non-farmers (controlled group) using interviews and measuring whole blood acetylcholinesterase (AChE) activity during August and October 2012.

RESULTS

Rice farmers had a significantly lower median AChE activity than the controls (9,594 vs. 10,530 U/L, respectively) and a significantly higher prevalence of difficulty in breathing and chest pain [odds ratio (OR) 2.8, P < 0.01 and OR 2.5, P < 0.05, respectively]. The prevalence of dry throat and cramp was associated with those farmers who sprayed and mixed pesticides (OR 2.5 and 2.6 for dry throat, OR 2.5 and 2.9 for cramp, respectively; P < 0.01). The prevalence of numbness and diarrhea was associated with those farmers who scattered seed (OR 2.2, P < 0.01 and OR 3.6, P < 0.05, respectively). The prevalence of numbness and increasing anxiety was also associated with those farmers who harvested crops (OR 3.6, P < 0.01 and OR 3.0, P < 0.05, respectively).

CONCLUSIONS

Our findings suggest that occupational pesticide exposure and agricultural tasks in the paddy field may be associated with the increasing prevalence of respiratory tract and muscle symptoms. This possibility warrants further investigation in more detail.

Occupational pesticide exposures and respiratory health

Pesticides have been widely used to control pest and pest-related diseases in agriculture, fishery, forestry and the food industry. In this review, we identify a number of respiratory symptoms and diseases that have been associated with occupational pesticide exposures. Impaired lung function has also been observed among people occupationally exposed to pesticides. There was strong evidence for an association between occupational pesticide exposure and asthma, especially in agricultural occupations. In addition, we found suggestive evidence for a link between occupational pesticide exposure and chronic bronchitis or COPD. There was inconclusive evidence for the association between occupational pesticide exposure and lung cancer. Better control of pesticide uses and enforcement of safety behaviors, such as using personal protection equipment (PPE) in the workplace, are critical for reducing the risk of developing pesticide-related symptoms and diseases. Educational training programs focusing on basic safety precautions and proper uses of personal protection equipment (PPE) are possible interventions that could be used to control the respiratory diseases associated with pesticide exposure in occupational setting.

Dermal exposure associated with occupational end use of pesticides and the role of protective measures

BACKGROUND

Occupational end users of pesticides may experience bodily absorption of the pesticide products they use, risking possible health effects. The purpose of this paper is to provide a guide for researchers, practitioners, and policy makers working in the field of agricultural health or other areas where occupational end use of pesticides and exposure issues are of interest.

METHODS

This paper characterizes the health effects of pesticide exposure, jobs associated with pesticide use, pesticide-related tasks, absorption of pesticides through the skin, and the use of personal protective equipment (PPE) for reducing exposure.

CONCLUSIONS

Although international and national efforts to reduce pesticide exposure through regulatory means should continue, it is difficult in the agricultural sector to implement engineering or system controls. It is clear that use of PPE does reduce dermal pesticide exposure but compliance among the majority of occupationally exposed pesticide end users appears to be poor. More research is needed on higher-order controls to reduce pesticide exposure and to understand the reasons for poor compliance with PPE and identify effective training methods.

Utilizing pyrosequencing and quantitative PCR to characterize fungal populations among house dust samples

Molecular techniques are an alternative to culturing and counting methods in quantifying indoor fungal contamination. Pyrosequencing offers the possibility of identifying unexpected indoor fungi. In this study, 50 house dust samples were collected from homes in the Yakima Valley, WA. Each sample was analyzed by quantitative PCR (QPCR) for 36 common fungi and by fungal tag-encoded flexible (FLX) amplicon pyrosequencing (fTEFAP) for these and additional fungi. Only 24 of the samples yielded amplified results using fTEFAP but QPCR successfully amplified all 50 samples. Over 450 fungal species were detected by fTEFAP but most were rare. Twenty-two fungi were found by fTEFAP to occur with at least an average of ≥0.5% relative occurrence. Many of these fungi seem to be associated with plants, soil or human skin. Combining fTEFAP and QPCR can enhance studies of fungal contamination in homes.

Gender differences in acute pesticide-related illnesses and injuries among farmworkers in the United States, 1998-2007

BACKGROUND

Farmworkers have a high risk for acute pesticide-related illness and injury, and the rate among female farmworkers is approximately twice as high as that among males. Surveillance data were used to identify reasons for this gender difference.

METHODS

We identified acute pesticide-related illness and injury cases among farmworkers from the Sentinel Event Notification System for Occupational Risks (SENSOR)-Pesticides Program and the California Department of Pesticide Regulation. Gender-specific associations with acute pesticide-related illness and injury were assessed using chi-square tests. National Agricultural Workers Survey data were also examined.

RESULTS

The over-representation of females among farmworker illness and injury cases was confined to females who did not handle pesticides (non-handlers). Female non-handler farmworkers who were affected were more likely to be working on fruit and nut crops, to be exposed to off-target pesticide drift, and to be exposed to fungicides and fumigants compared to males.

CONCLUSIONS

Although there is an increased risk for acute pesticide-related illness and injury among female farmworkers, the absolute number of farmworkers with acute pesticide-related illness and injury is far higher among males than females. Furthermore, farmworkers have little or no control over many of the identified contributing factors that led to illness and injury. Stringent enforcement of existing regulations and enhanced regulatory efforts to protect against off-target drift exposures may have the highest impact in reducing acute pesticide-related illness and injury among farmworkers.

Determinants of atrazine contamination in the homes of commercial pesticide applicators across time

Twenty-nine commercial pesticide applicator households in eastern Iowa were enrolled to investigate in-home contamination of atrazine, the most commonly used corn herbicide in the Unites States. From each home, four vacuum dust samples were collected during atrazine application season (Visit 1) and again 6 months later during winter months (Visit 2). Samples were taken from the following locations: primary entryway for pesticide applicator, living room, master bedroom, and kitchen. The applicator completed an atrazine handling log and household questionnaire with spouse. Of the 230 dust samples, only 2 were below the level of detection, 2 ng of atrazine per gram (ng/g) of fine dust (dust particle size 5-150 μm). Dust levels were standardized to chemical loading. During application season the entryway (2.68 ng/cm(2)) and kitchen (0.47 ng/cm(2)) had the highest geometric mean atrazine chemical loading. The entryway chemical loading during Visit 2 was the second highest aggregate (0.55 ng/cm(2)). Aggregate concentrations were significantly higher at Visit 1 compared with Visit 2 when paired by location (p≤0.02). Analysis showed that job (application, mixing/loading, or both) was not associated with in-home atrazine contamination. Linear regression showed a strong positive association between atrazine handling (number of acres applied with atrazine, number of days atrazine handled, and pounds of atrazine handled) and aggregate dust chemical loading from both visits (p = 0.06, 0.03, and 0.10, respectively). Frequency of vacuuming was inversely associated with Visit 2 concentrations (p = 0.10) and showed a weaker association with Visit 1 (p = 0.30). Removing shoes outside the home was associated with lower atrazine chemical loading (p = 0.03), and applicators changing work clothes in the master bedroom had significantly increased atrazine chemical loading in master bedrooms (p = 0.01). Changes in hygiene practices for commercial pesticide applicators could significantly reduce atrazine and, likely, other pesticide contaminations in the home.

Airborne concentrations of organophosphorus pesticides in Korean pesticide manufacturing/formulation workplaces

Pesticide manufacturing/formulation workers rather than farmers or applicators or people living with them are primarily exposed to organophosphorus pesticides (OPs). However, airborne concentrations in the workplace have rarely been determined. A total of 121 air samples (personal or area sampling) were collected at 4 factories where chlorpyrifos, EPN, parathion, and phorate, were manufactured/formulated from March through July, 2007-2008. Samples were collected by the National Institute for Occupational Safety and Health (NIOSH) method and were analyzed by GC-MS. The geometric mean (GM) level of airborne chlorpyrifos was 0.17 mg/m(3), 85% Korean Occupational Exposure Limit (KOEL) of 0.2 mg/m(3), and at 95% confidence, airborne concentrations exceeded the KOEL 58.8% of the time or less, indicating that this concentration level was unacceptable according to exposure assessment using a LogNorm2(®). However, compared with levels of TLV and/or PEL and/or WEL, the GM concentration levels of other OPs were remarkably low (range, 0.1-15.0%) and that these levels of concentrations to the other OPs were acceptable. The levels of airborne concentrations of OPs depended on isolation of the process; in other words, the levels depended on the extent to which the process was automated. The reason that the airborne concentration levels, except for those of chlorpyrifos, were very much lower than expected may be attributable to the fact that there was not exposed to 100% toxic active ingredients in pesticide formulation workplaces because of the use of supplemental agents or additives to produce complete pesticides. This study is limited since there were seldom or neither any data of previous studies to be compared with the study results nor dermal exposure data. The results were used to revise KOELs for OPs in 2010.

Disproportionate exposures in environmental justice and other populations: the importance of outliers

We examined traditional environmental justice populations and other groups whose exposure to contaminants is often disproportionately high. Risk assessment methods may not identify these populations, particularly if they are spatially dispersed. We suggest using a National Health and Nutrition Examination Survey approach to oversample minority communities and develop methods for assessing exposure at different distances from pollution sources; publishing arithmetic and geometric means and full distributions for minority populations; and paying particular attention to high-end exposures. Means may sufficiently characterize populations as a whole but are inadequate in identifying vulnerable groups and subgroups. The number of individuals above the 95th percentile of any distribution may be small and unrepresentative, but these outliers are the ones who need to be protected.

Farmers' perceptions of safe use of pesticides: determinants and training needs

PURPOSE

With focus on the impact of age, farmers' perceptions of importance and competence on pesticide safety measures as well as factors that influence these perceptions were explored in Fars Province of Iran. Farmers' training needs on the pesticide safety measures were also identified and compared using the Borich Needs Assessment Model.

METHODS

The study included 155 farmers who were up to 35 years old (young farmers), above 35 up to 50 years old (middle-aged farmers), and above 50 years old (old farmers). Farmers evaluated twenty-two pesticide safety measures divided into three stages of pesticide handling, i.e., before, during, and after use.

RESULTS

There was no significant relationship either between age and total importance of the safety measures or between age and total competence on the safety measures due to the impacts of other mediating variables. The most important predictors for the perceived importance and competence of farmers on the safety measures were the experience of pesticide-related adverse health effects in the past and the formal education of farmers, respectively.

CONCLUSIONS

The relationship between farmers' age and these two variables should not be considered either positively or negatively for predicting farmers' attitudes on safety issues of pesticide use without taking into account other mediating variables that can also affect farmers' behavior. Differences in the perceived importance and competence of farmers on the safety measures revealed considerably different needs of farmers for future training as a result of differences in age along with other background characteristics.

Where's the dust? Characterizing locations of azinphos-methyl residues in house and vehicle dust among farmworkers with young children

Organophosphate pesticides are commonly used in the United States, and farmworkers are at risk for chronic exposure. Using data from a community randomized trial to interrupt the take-home pathway of pesticide exposure, we examined the association between floor surface type (smooth floor, thin carpet, and thick carpet) and rooms in which dust samples were collected (living room vs. non-living room) and concentrations of azinphos-methyl residues in home environments. We also examined the association between vehicle type (truck, auto, or other) and footwell floor surfaces (carpeted, smooth surface, or no mat) and concentrations of azinphos-methyl in vehicle dust samples. Dust samples were collected from 203 and 179 households and vehicles, respectively. All households had at least one child aged 2-6. Vehicle dust samples were collected from footwells of the vehicle used for commuting to and from work. A total of 183 samples were collected from living rooms, and 20 were collected from other rooms in the home. Forty-two samples were collected from thick carpets, 130 from thin carpets, and 27 from smooth floor surfaces. Thick and thin carpets had a significantly greater dust mass than smooth floor surfaces (6.0 g/m(2) for thick carpets, 7.8 g/m(2) for thin carpets, and 1.5 g/m(2) for smooth surfaces). Of the 179 vehicle samples, 113 were from cars, 34 from trucks, and 32 from other vehicles. Vehicles with no mats had a significantly higher mass of dust (21.3 g) than those with hard mats (9.3 g) but did not differ from vehicles with plush mats (12.0 g). Further research is needed to characterize the environment in which children may be exposed to pesticides.

Job demands and pesticide exposure among immigrant Latino farmworkers

The goal of this study was to understand the potential threat of job stressors to farmworker health. To accomplish this goal we studied pesticide exposure, an issue with immediate and long-term health consequences, and predictions from the Demands-Control model of occupational stress. Longitudinal, self-report data and urine samples were collected at monthly intervals from a cohort of Latino farmworkers (N = 287) during the 2007 agricultural season. The primary hypothesis was that greater exposure to psychological demands, physical exertion, and hazardous work conditions are associated with greater odds of detecting dialkylphosphate (DAP) urinary pesticide metabolites, biomarkers indicating exposure to pesticides. Contrary to this hypothesis, results indicated that none of the elements of the Demands-Control model were independently associated with detection of DAP urinary pesticide metabolites. However, analyses produced several interaction effects, including evidence that high levels of control may buffer the effects of physical job demands on detection of DAP urinary pesticide metabolites.

Monitoring health implications of pesticide exposure in factory workers in Pakistan

The study aimed to determine the hazardous health effects of pesticides exposure in the factory workers by measuring plasma cholinesterase (PChE), pesticides residues, and renal and hepatic biochemical markers. In addition, we also assessed the knowledge, attitudes, and safety practices adopted by the industrial workers. The study was conducted in three different sizes of factories located in Lahore (large), Multan (medium), and Karachi (small) in Pakistan. Total 238 adult males consisting of 184 pesticide industrial workers (exposed group) from large-sized (67), medium-sized (61), small-sized (56) industrial formulation factories, and 54 controls (unexposed) were included in the study. All the participants were male of aged 18 to 58 years. PChE levels were estimated by Ellmann's method. Plasma pesticides residue analysis was performed by using reverse phase C-18 on high-performance liquid chromatograph and GC with NPD detector. Plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine, urea, and gamma glutamyltransferase (GGT) were measured on Selectra E auto analyzer. Plasma and C-reactive protein was analyzed by Immulite 1000. The results revealed a significant decrease in plasma post exposure PChE levels (<30%) as compared to baseline in the workers of small (29%) and medium (8%) industrial units (p < 0.001). Plasma cypermethrin, endosulfan, imidacloprid, thiodicarb, carbofuran, and methamidophos levels were found to be higher than allowable daily intake. Serum AST, ALT, creatinine GGT, malondialdehyde, total antioxidant, and CRP were significantly raised among the workers of small and medium pesticide formulation factories as compared to large industrial unit and controls (p < 0.001). The study demonstrated that unsafe practices among small- and medium-sized pesticides industrial workers cause significant increase in pesticide exposure, oxidative stress, and derangement of hepatic and renal function.