title: Agricultural pesticide use and hypospadias in eastern Arkansas.
abstract: BACKGROUND
  We assessed the relationship between hypospadias and proximity to agricultural pesticide applications using a GIS-based exposure method.
  
  
  METHODS
  We obtained information for 354 cases of hypospadias born between 1998 and 2002 in eastern Arkansas; 727 controls were selected from birth certificates. We classified exposure on pounds of pesticides (estimated by crop type) applied or persisting within 500 m of each subject's home during gestational weeks 6 to 16. We restricted our analyses to 38 pesticides with some evidence of reproductive, developmental, estrogenic, and/or antiandrogenic effects. We estimated timing of pesticide applications using crop phenology and published records.
  
  
  RESULTS
  Gestational age at birth [odds ratio (OR) = 0.91; 95% confidence interval (CI), 0.83-0.99], parity (OR = 0.79; 95% CI, 0.65-0.95), and delaying prenatal care until the third trimester (OR = 4.04; 95% CI, 1.46-11.23) were significantly associated with hypospadias. Risk of hypospadias increased by 8% for every 0.05-pound increase in estimated exposure to diclofop-methyl use (OR = 1.08; 95% CI, 1.01-1.15). Pesticide applications in aggregate (OR = 0.82; 95% CI, 0.70-0.96) and applications of alachlor (OR = 0.56; 95% CI, 0.35-0.89) and permethrin (OR = 0.37; 95% CI, 0.16-0.86) were negatively associated with hypospadias.
  
  
  CONCLUSIONS
  Except for diclofop-methyl, we did not find evidence that estimated exposure to pesticides known to have reproductive, developmental, or endocrine-disrupting effects increases risk of hypospadias. Further research on the potential effects of exposure to diclofop-methyl is recommended.
authors.affiliation: Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado 80523-1681, USA.
authors.forename: Kristy J
authors.initials: KJ
authors.lastname: Meyer
authors.forename: John S
authors.initials: JS
authors.lastname: Reif
authors.forename: D N Rao
authors.initials: DN
authors.lastname: Veeramachaneni
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Luben
authors.forename: Bridget S
authors.initials: BS
authors.lastname: Mosley
authors.forename: John R
authors.initials: JR
authors.lastname: Nuckols
mesh_terms: D000382:Agricultural Workers' Diseases / Q000139:chemically induced*; D001131:Arkansas; D006801:Humans; D007021:Hypospadias / Q000139:chemically induced*; D008297:Male; D010575:Pesticides / Q000633:toxicity*
chemical_list: D010575:Pesticides