Hilary Zetlen

Project title: Pesticide Exposure Assessment and Control in Orchards: Spectrofluorometric Analysis of Fluorescent Tracers in Air, Deposition and Wipe Samples

Degree: MPH | Program: Environmental and Occupational Health (EOH) | Project type: Thesis/Dissertation
Completed in: 2011



Pesticide Exposure in Farmworkers

Farmworkers are at risk for several occupational hazards, including injury, respiratory illness, and both chronic and acute pesticide exposure. There is an unfortunate paucity of comprehensive data on the occupational health and safety of the farmworker population, much of which is comprised of migrant or hired workers. Available estimates put annual pesticide poisonings in the tens of thousands in the United States and in the hundreds of thousands worldwide annually. Farmworkers, their families, and agricultural communities are all at risk for the effects of occupational pesticide exposure. Assessing pesticide exposure in this population is critical to reducing the potential short- and long-term health effects of these exposures.

A variety of factors influence pesticide exposure potential in agricultural workers. Job duties, occupational behaviors, and workplace environment all play an important role in influencing farmworker pesticide exposure. Exposure potential differs across job tasks such as mixing and loading pesticides, applying pesticides, thinning orchard trees, and picking fruit. Occupational behaviors influencing exposure include use of PPE, hand washing, and changing of boots. These behaviors also influence the potential of pesticide exposure in children and family members in farmworker homes and communities. Effective pesticide education and safety training is also instrumental moderating pesticide exposure among farmworkers.

The consequence of occupational pesticide exposure are significant. Acute pesticide exposure can result in nausea, vomiting, dizziness, weakness, tremor, and respiratory symptoms. Acute exposure may also result in significant, long-term neuropsychological abnormalities. Chronic exposure to pesticides can have a variety of effects on both worker and family health. Farmworkers exposed to pesticides have significantly depressed blood acetylcholinesterase levels in comparison to nonfarmworker controls, which is associated with a variety of neurological and physiological symptoms. Chronic low-level exposure is associated with cognitive deficits and depression, and the children of farmworkers have demonstrated deficits in neurobehavioral and sensorimotor development as a result of paraoccupational exposure. In addition, pesticides are suspected etiologic agents in the development of several cancers, particularly childhood leukemias.