Lara E. Whalley

Migrant farmworkers' housing conditions across an agricultural season in North Carolina.

BACKGROUND Several studies have documented poor housing conditions for farmworkers but none has focused on migrant farmworker housing, which is often provided as a condition of employment. Farmworker housing quality is regulated, but little documentation exists of compliance with regulations. METHODS A 2007 survey of 43 randomly selected farmworker camps and a 2008 survey of 27 camps randomly selected from the 2007 sample documented housing conditions via interviewer administered questionnaire and housing checklist. RESULTS Substandard conditions are common in migrant housing. All camps had at least one exterior housing problem; 93% had at least one interior problem. Housing conditions worsen across the agricultural season. Characteristics including no residents with H2A visa and 11 or more residents are associated with poorer conditions. CONCLUSIONS Housing standards are not adequately enforced. An increase in post-occupancy inspections and targeting camps with characteristics that place them at increased risk for substandard conditions are recommended.

Variation across the agricultural season in organophosphorus pesticide urinary metabolite levels for Latino farmworkers in eastern North Carolina: Project design and descriptive results

BACKGROUND Community Participatory Approach to Measuring Farmworker Pesticide Exposure, PACE3, used a longitudinal design to document pesticide biomarkers among farmworkers. This article presents an overview of PACE3 and provides a descriptive analysis of participant characteristics and one set of pesticide biomarkers, the dialkylphosphate (DAP) urinary metabolites of organophosphorus (OP) pesticides. METHODS Two hundred eighty seven farmworkers were recruited during 2007 from 44 farmworker camps in 11 eastern North Carolina counties. Participants provided interviews, urine samples, blood samples, and saliva samples up to four times at monthly intervals beginning in May. A total of 939 data points were collected. RESULTS Farmworkers were largely men (91.3%) from Mexico (94.8%) with a mean age of 33.7 years (SE 0.82); 23.3% spoke an indigenous language. Across all data points, frequencies of detection and median urinary concentrations were 41.3% and 0.96 microg/L for dimethylphosphate (DMP), 78.3% and 3.61 microg/L for dimethylthiophosphate (DMTP), 33.3% and 0.04 microg/L for dimethyldithiophosphate (DMDTP), 40.5% and 0.87 microg/L for diethylphosphate (DEP), 32.3% and 0.17 microg/L for diethylthiophosphate (DETP), and 8.09% and 0.00 microg/L for diethyldithiophosphate (DEDTP). The frequencies of detection and urinary concentrations of the DAP metabolites increased during the season. CONCLUSIONS More PACE3 participants were from Mexico, male, migrant workers, and spoke an indigenous language compared to national data. PACE3 participants had comparable frequencies of detection and urinary metabolite concentrations with participants in other studies. Variability in the frequencies of detection and urinary concentrations of the DAP metabolites indicates the importance of longitudinal studies of biomarkers of currently used pesticides in farmworker populations.

Migrant Farmworker Field and Camp Safety and Sanitation in Eastern North Carolina

ABSTRACT Migrant farmworkers are exposed to numerous workplace hazards, with pesticides being a ubiquitous occupational exposure. This analysis describes farmworker experiences of field and camp safety conditions and their safety behaviors, and delineates farmworker characteristics associated with safety conditions and behaviors. Data were collected from 255 migrant farmworkers up to 4 times at monthly intervals during the 2007 agricultural season in eastern North Carolina. Measures assess field safety conditions and camp sanitation required by federal and state regulations. Most of the farmworkers were Latino men from Mexico. About 20% had not received pesticide safety training across the season; many of those who received such training did not understand it. Water for washing was not available for about one-third of the workers; soap and towels were not available for over half. About 20% lived in camps with more than eight workers per showerhead and about 20% lived in camps that failed to meet the standard of 30 or fewer workers per washtub/washing machine. Important predictors of variation included H2A visa status and years of experience. Four themes emerged from the analysis: (1) safety regulations are not consistently met; (2) farmworkers do not always practice safety behaviors; (3) camps become more crowded and less compliant during the middle of the agricultural season; and (4) workers with H2A visas experience better conditions and practice more safety behaviors than do workers who do not have H2A visas. Further research needs to account for social and cultural factors. Regulations should be compared with pesticide metabolite levels to measure their effectiveness. More effort is needed to enforce existing regulations.

Seasonal Variation in the Measurement of Urinary Pesticide Metabolites among Latino Farmworkers in Eastern North Carolina

Abstract This analysis describes the detection of urinary pesticide metabolites for Latino farmworkers across the agricultural season. Two hundred and eighty four farmworkers were recruited from 44 camps in eastern North Carolina in 2007. Data were collected at one month intervals for a total of 939 data points. The OP insecticide metabolites 3,5,6-trichloropyridinol (46.2%), malathion dicarboxylic acid (27.7%), and para-nitrophenol (97.4%); the pyrethroid metabolite 3-phenoxybenzoic acid (56.4%); and the herbicides 2,4-D (68.1%), acetochlor (29.2%), and metolachlor (16.9%) were found in sizable percentages of the samples. The percentage of farmworkers for whom metabolites were detected varied across the agricultural season. None of the farmworker characteristics were significantly associated with the detection of any pesticide metabolite. Seasonality overrides the effects of other farmworker characteristics in predicting detection of pesticide urinary metabolites. Future research needs to collect multiple exposure measures at frequent intervals over an extended period to characterize factors associated with exposure.

HIV and sexually transmitted disease risk among male Hispanic/Latino migrant farmworkers in the Southeast: Findings from a pilot CBPR study

BACKGROUND Little is known about the HIV and sexually transmitted disease (STD) risk behaviors of Hispanic/Latino farmworkers. This study was designed to describe risk factors for HIV and STD infection, explore personal characteristics associated with condom use, and evaluate the feasibility of collecting self-report and biomarker data from farmworkers. METHODS Self-report and biomarker data were collected from a sample of male farmworkers living in 29 camps in North Carolina during the 2008 growing season. RESULTS Over half of the 100 male workers, mean age 37.1 (range 19-68) years, reported binge drinking during the past 12 months. Forty percent of those who reported having had sex during the past 3 months indicated that they were under the influence of alcohol. Knowledge of HIV and STD transmission and prevention was low. Among the 25 workers who reported having had sex during the past 3 months, 16 and 2 reported using a condom consistently during vaginal and anal sex, respectively, and nearly 1 out of 6 workers reported paying a woman to have sex. Two workers tested positive for syphilis. CONCLUSIONS Farmworkers in this sample demonstrated significant HIV and STD risks; however, when exploring potential bivariate associations with consistent condom use no statistically significant associations were identified perhaps due to the small sample size. Because it was feasible to collect self-report and biomarker data related to HIV and STDs from Hispanic/Latino farmworkers, research needed to further explore risks and develop interventions to reduce disease exposure and transmission among this vulnerable population.

Heavy metals exposures among Mexican farmworkers in eastern North Carolina.

BACKGROUND Immigrant farmworkers are a population at risk for numerous environmental and occupational exposures. The metals arsenic, lead, mercury, and cadmium are known neurotoxins to which workers can be exposed both in the US and in their country of origin. Because farmworkers are exposed to neurotoxic pesticides, they may be at risk for adverse health effects from the combined exposure. OBJECTIVES To examine the relationship between exposure to metals, as measured in urine, with personal and work-related characteristics of Mexican migrant and seasonal farmworkers in the US. METHODS We analyzed data on metals found in urine of 258 farmworkers recruited from 44 camps in eastern North Carolina in 2007. Geometric means and 95% confidence intervals (CI) were used to compare data with data from the National Health and Nutrition Examination Survey (NHANES). We used multivariate regression models fitted for each metal to estimate the association of creatinine-corrected urinary metals and worker characteristics related to environmental and occupational exposures. RESULTS Geometric mean urinary metals concentrations (mug/g creatinine) exceeded NHANES reference values for arsenic (13.23 [CI 11.11, 15.35] vs. 8.55 [CI 7.23, 9.86]) and lead (1.26 [CI 1.08, 1.43] vs. 0.63 [CI 0.60, 0.66]). Age, being from the central region of Mexico, and pack years of cigarette smoking were significant predictors of metals exposure; being a current smoker and years worked in US agriculture were not. CONCLUSIONS This first study to examine indicators of worker body burdens of metals shows that workers have body burdens related to exposures other than work in the US. Further research should address their risk for adverse health outcomes due to combined exposures to neurotoxins in 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.

Teledermatology Consultations Provide Specialty Care for Farmworkers in Rural Clinics

CONTEXT Rural patients have limited access to dermatologic care. Farmworkers have high rates of skin disease and limited access to care. PURPOSE This exploratory study assessed whether teledermatology consultations could help meet the needs of health care providers for farmworkers in rural clinics. METHODS Dermatologists provided 79 consultations, using store-and-forward teledermatology, to farmworkers who presented with a skin disease to rural North Carolina clinics. Clinic providers rated the value of the consultation. FINDINGS Most requests for consultations (94%) came from family nurse practitioners or physician assistants. Twelve percent of consultations were rated somewhat helpful, and the remainder helpful or very helpful. After receiving the consultation, providers changed the diagnosis in 13% of cases. The consultation led providers to contact or attempt to contact 21% of patients to change treatment recommendations. CONCLUSIONS Access to expert dermatologic services is needed by rural health care providers. Teledermatology consultations may be a helpful tool to meet this need.

Evaluation of Candidate Genes for Cholinesterase Activity in Farmworkers Exposed to Organophosphorus Pesticides: Association of Single Nucleotide Polymorphisms in BCHE

Background Organophosphate pesticides act as cholinesterase inhibitors. For those with agricultural exposure to these chemicals, risk of potential exposure-related health effects may be modified by genetic variability in cholinesterase metabolism. Cholinesterase activity is a useful, indirect measurement of pesticide exposure, especially in high-risk individuals such as farmworkers. To understand fully the links between pesticide exposure and potential human disease, analyses must be able to consider genetic variability in pesticide metabolism. Objectives We studied participants in the Community Participatory Approach to Measuring Farmworker Pesticide Exposure (PACE3) study to determine whether cholinesterase levels are associated with single-nucleotide polymorphisms (SNPs) involved in pesticide metabolism. Methods Cholinesterase levels were measured from blood samples taken from 287 PACE3 participants at up to four time points during the 2007 growing season. We performed association tests of cholinesterase levels and 256 SNPs in 30 candidate genes potentially involved in pesticide metabolism. A false discovery rate (FDR) p-value was used to account for multiple testing. Results Thirty-five SNPs were associated (unadjusted p < 0.05) based on at least one of the genetic models tested (general, additive, dominant, and recessive). The strongest evidence of association with cholinesterase levels was observed with two SNPs, rs2668207 and rs2048493, in the butyrylcholinesterase (BCHE) gene (FDR adjusted p = 0.15 for both; unadjusted p = 0.00098 and 0.00068, respectively). In participants with at least one minor allele, cholinesterase levels were lower by 4.3–9.5% at all time points, consistent with an effect that is independent of pesticide exposure. Conclusions Common genetic variation in the BCHE gene may contribute to subtle changes in cholinesterase levels.

Contact dermatitis in tobacco farmworkers

Occupational skin disease is highly prevalent among agricultural workers. Tobacco cultivation and harvest are particularly hazardous for farmworkers. We report 5 migrant Latino farmworkers in North Carolina with contact dermatitis related to tobacco work. These cases show a characteristic distribution of contact dermatitis; the flexural and medial surfaces of the upper extremities were affected in each case, whereas most cases showed some involvement of the torso and axilla. This pattern most likely reflects a common occupational practice of holding the tobacco leaves under the arm and pressed against the body during harvesting.