title: Attention-deficit/hyperactivity disorder and urinary metabolites of organophosphate pesticides.
abstract: OBJECTIVE
  The goal was to examine the association between urinary concentrations of dialkyl phosphate metabolites of organophosphates and attention-deficit/hyperactivity disorder (ADHD) in children 8 to 15 years of age.
  
  
  METHODS
  Cross-sectional data from the National Health and Nutrition Examination Survey (2000-2004) were available for 1139 children, who were representative of the general US population. A structured interview with a parent was used to ascertain ADHD diagnostic status, on the basis of slightly modified criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition.
  
  
  RESULTS
  One hundred nineteen children met the diagnostic criteria for ADHD. Children with higher urinary dialkyl phosphate concentrations, especially dimethyl alkylphosphate (DMAP) concentrations, were more likely to be diagnosed as having ADHD. A 10-fold increase in DMAP concentration was associated with an odds ratio of 1.55 (95% confidence interval: 1.14-2.10), with adjustment for gender, age, race/ethnicity, poverty/income ratio, fasting duration, and urinary creatinine concentration. For the most-commonly detected DMAP metabolite, dimethyl thiophosphate, children with levels higher than the median of detectable concentrations had twice the odds of ADHD (adjusted odds ratio: 1.93 [95% confidence interval: 1.23-3.02]), compared with children with undetectable levels.
  
  
  CONCLUSIONS
  These findings support the hypothesis that organophosphate exposure, at levels common among US children, may contribute to ADHD prevalence. Prospective studies are needed to establish whether this association is causal.
authors.affiliation: Department of Environmental Health, School of Public Health, Harvard University, Boston, MA, USA. maryse.bouchard@umontreal.ca
authors.forename: Maryse F
authors.initials: MF
authors.lastname: Bouchard
authors.forename: David C
authors.initials: DC
authors.lastname: Bellinger
authors.forename: Robert O
authors.initials: RO
authors.lastname: Wright
authors.forename: Marc G
authors.initials: MG
authors.lastname: Weisskopf
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology / Q000652:urine*; D002648:Child; D003404:Creatinine / Q000652:urine; D003430:Cross-Sectional Studies; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D009749:Nutrition Surveys; D010755:Organophosphates / Q000652:urine*; D010575:Pesticides / Q000652:urine*; D015995:Prevalence; D014481:United States / Q000453:epidemiology
chemical_list: D010755:Organophosphates; D010575:Pesticides; D003404:Creatinine