title: Determinants of captan air and dermal exposures among orchard pesticide applicators in the Agricultural Health Study.
abstract: OBJECTIVE
  To identify and quantify determinants of captan exposure among 74 private orchard pesticide applicators in the Agricultural Health Study (AHS). To adjust an algorithm used for estimating pesticide exposure intensity in the AHS based on these determinants and to compare the correlation of the adjusted and unadjusted algorithms with urinary captan metabolite levels.
  
  
  METHODS
  External exposure metrics included personal air, hand rinse, and dermal patch samples collected from each applicator on 2 days in 2002-2003. A 24-h urine sample was also collected. Exposure determinants were identified for each external metric using multiple linear regression models via the NLMIXED procedure in SAS. The AHS algorithm was adjusted, consistent with the identified determinants. Mixed-effect models were used to evaluate the correlation between the adjusted and unadjusted algorithm and urinary captan metabolite levels.
  
  
  RESULTS
  Consistent determinants of captan exposure were a measure of application size (kilogram of captan sprayed or application method), wearing chemical-resistant (CR) gloves and/or a coverall/suit, repairing spray equipment, and product formulation. Application by airblast was associated with a 4- to 5-fold increase in exposure as compared to hand spray. Exposure reduction to the hands, right thigh, and left forearm from wearing CR gloves averaged ∼80%, to the right and left thighs and right forearm from wearing a coverall/suit by ∼70%. Applicators using wettable powder formulations had significantly higher air, thigh, and forearm exposures than those using liquid formulations. Application method weights in the AHS algorithm were adjusted to nine for airblast and two for hand spray; protective equipment reduction factors were adjusted to 0.2 (CR gloves), 0.3 (coverall/suit), and 0.1 (both).
  
  
  CONCLUSIONS
  Adjustment of application method, CR glove, and coverall weights in the AHS algorithm based on our exposure determinant findings substantially improved the correlation between the AHS algorithm and urinary metabolite levels.
authors.affiliation: National Institute for Occupational Safety and Health, 4676 Columbia Parkway, Cincinnati, OH 45226, USA. chines@cdc.gov
authors.forename: Cynthia J
authors.initials: CJ
authors.lastname: Hines
authors.forename: James A
authors.initials: JA
authors.lastname: Deddens
authors.forename: Joseph
authors.initials: J
authors.lastname: Coble
authors.forename: Freya
authors.initials: F
authors.lastname: Kamel
authors.forename: Michael C R
authors.initials: MC
authors.lastname: Alavanja
mesh_terms: D000383:Agriculture / Q000379:methods*; D000395:Air Pollutants, Occupational / Q000032:analysis* / Q000652:urine; D000465:Algorithms; D002215:Captan / Q000008:administration & dosage / Q000032:analysis* / Q000652:urine; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring / Q000379:methods; D005542:Forearm; D005638:Fruit; D005659:Fungicides, Industrial / Q000008:administration & dosage / Q000032:analysis* / Q000652:urine; D008401:Gas Chromatography-Mass Spectrometry; D006225:Hand; D006306:Health Surveys / Q000706:statistics & numerical data; D006801:Humans; D016014:Linear Models; D008956:Models, Chemical; D016273:Occupational Exposure / Q000032:analysis / Q000706:statistics & numerical data*; D016272:Occupational Health; D011481:Protective Clothing / Q000706:statistics & numerical data; D012867:Skin / Q000737:chemistry*; D013848:Thigh
chemical_list: D000395:Air Pollutants, Occupational; D005659:Fungicides, Industrial; D002215:Captan