title: Determining the probability of pesticide exposures among migrant farmworkers: results from a feasibility study.
abstract: BACKGROUND
  Migrant and seasonal farmworkers are exposed to pesticides through their work with crops and livestock. Because workers are usually unaware of the pesticides applied, specific pesticide exposures cannot be determined by interviews. We conducted a study to determine the feasibility of identifying probable pesticide exposures based on work histories.
  
  
  METHODS
  The study included 162 farm workers in seven states. Interviewers obtained a lifetime work history including the crops, tasks, months, and locations worked. We investigated the availability of survey data on pesticide use for crops and livestock in the seven pilot states. Probabilities of use for pesticide types (herbicides, insecticides, fungicides, etc.) and specific chemicals were calculated from the available data for two farm workers. The work histories were chosen to illustrate how the quality of the pesticide use information varied across crops, states, and years.
  
  
  RESULTS
  For most vegetable and fruit crops there were regional pesticide use data in the late 1970s, no data in the 1980s, and state-specific data every other year in the 1990s. Annual use surveys for cotton and potatoes began in the late 1980s. For a few crops, including asparagus, broccoli, lettuce, strawberries, plums, and Christmas trees, there were no federal data or data from the seven states before the 1990s.
  
  
  CONCLUSIONS
  We conclude that identifying probable pesticide exposures is feasible in some locations. However, the lack of pesticide use data before the 1990s for many crops will limit the quality of historic exposure assessment for most workers.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland 20892-7240, USA.
authors.forename: M H
authors.initials: MH
authors.lastname: Ward
authors.forename: J R
authors.initials: JR
authors.lastname: Prince
authors.forename: P A
authors.initials: PA
authors.lastname: Stewart
authors.forename: S H
authors.initials: SH
authors.lastname: Zahm
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000383:Agriculture / Q000706:statistics & numerical data*; D003625:Data Collection; D005240:Feasibility Studies; D005260:Female; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D016273:Occupational Exposure / Q000032:analysis / Q000706:statistics & numerical data*; D010575:Pesticides; D010865:Pilot Projects; D011336:Probability; D011795:Surveys and Questionnaires; D014171:Transients and Migrants / Q000706:statistics & numerical data*; D014481:United States
chemical_list: D010575:Pesticides