title: Association of pyrethroid pesticide exposure with attention-deficit/hyperactivity disorder in a nationally representative sample of U.S. children.
abstract: BACKGROUND
  Pyrethroid pesticides cause abnormalities in the dopamine system and produce an ADHD phenotype in animal models, with effects accentuated in males versus females. However, data regarding behavioral effects of pyrethroid exposure in children is limited. We examined the association between pyrethroid pesticide exposure and ADHD in a nationally representative sample of US children, and tested whether this association differs by sex.
  
  
  METHODS
  Data are from 8-15 year old participants (N = 687) in the 2001-2002 National Health and Nutrition Examination Survey. Exposure was assessed using concurrent urinary levels of the pyrethroid metabolite 3-phenoxybenzoic acid (3-PBA). ADHD was defined by either meeting Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition criteria on the Diagnostic Interview Schedule for Children (DISC) or caregiver report of a prior diagnosis. ADHD symptom counts were determined via the DISC. Multivariable logistic regression examined the link between pyrethroid exposure and ADHD, and poisson regression investigated the link between exposure and ADHD symptom counts.
  
  
  RESULTS
  Children with urinary 3-PBA above the limit of detection (LOD) were twice as likely to have ADHD compared with those below the LOD (adjusted odds ratio [aOR] 2.42; 95 % confidence interval [CI] 1.06, 5.57). Hyperactive-impulsive symptoms increased by 50 % for every 10-fold increase in 3-PBA levels (adjusted count ratio 1.50; 95 % CI 1.03, 2.19); effects on inattention were not significant. We observed possible sex-specific effects: pyrethroid biomarkers were associated with increased odds of an ADHD diagnosis and number of ADHD symptoms for boys but not girls.
  
  
  CONCLUSIONS
  We found an association between increasing pyrethroid pesticide exposure and ADHD which may be stronger for hyperactive-impulsive symptoms compared to inattention and in boys compared to girls. Given the growing use of pyrethroid pesticides, these results may be of considerable public health import.
authors.affiliation: Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA. Melissa.wagner.schuman@cchmc.org.
authors.forename: Melissa
authors.initials: M
authors.lastname: Wagner-Schuman
authors.affiliation: Rutgers Robert Wood Johnson Medical School and Environmental and Occupational Health Sciences Institute, 170 Frelinghuysen Road, EOHSI 340, Piscataway, NJ, USA. jricha3@eohsi.rutgers.edu.|Department of Environmental and Occupational Medicine, Piscataway, NJ, 08854, USA. jricha3@eohsi.rutgers.edu.
authors.forename: Jason R
authors.initials: JR
authors.lastname: Richardson
authors.affiliation: University of Rochester School of Medicine and Dentistry, 265 Crittenden Blvd, Rochester, NY, USA. peggy_auinger@urmc.rochester.edu.|Department of Neurology, Center for Human Experimental Therapeutics, Rochester, NY, 14642, USA. peggy_auinger@urmc.rochester.edu.
authors.forename: Peggy
authors.initials: P
authors.lastname: Auinger
authors.affiliation: Brown University School of Public Health, Box G-S121-2, Providence, RI, 02912, USA. joseph_braun_1@brown.edu.
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Braun
authors.affiliation: Simon Fraser University, 3415 Ash Street, Vancouver, BC, Canada. blanphear@sfu.ca.|Child & Family Research Institute, BC Children's Hospital, Vancouver, BC, Canada. blanphear@sfu.ca.
authors.forename: Bruce P
authors.initials: BP
authors.lastname: Lanphear
authors.affiliation: Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA. jeff.epstein@cchmc.org.|Division of Behavioral Medicine and Clinical Psychology, Cincinnati, OH, 45229, USA. jeff.epstein@cchmc.org.
authors.forename: Jeffery N
authors.initials: JN
authors.lastname: Epstein
authors.affiliation: Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA. Kimberly.yolton@cchmc.org.|Division of General and Community Pediatrics, Cincinnati, OH, 45229, USA. Kimberly.yolton@cchmc.org.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Yolton
authors.affiliation: Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH, 45229, USA. tanya.froehlich@cchmc.org.|Division of Developmental and Behavioral Pediatrics, Cincinnati, OH, 45229, USA. tanya.froehlich@cchmc.org.
authors.forename: Tanya E
authors.initials: TE
authors.lastname: Froehlich
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000139:chemically induced / Q000453:epidemiology*; D001565:Benzoates / Q000633:toxicity* / Q000652:urine; D015415:Biomarkers / Q000652:urine; D002648:Child; D003430:Cross-Sectional Studies; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D008297:Male; D009749:Nutrition Surveys; D010575:Pesticides / Q000633:toxicity* / Q000652:urine; D015995:Prevalence; D011722:Pyrethrins / Q000633:toxicity* / Q000652:urine; D012959:Socioeconomic Factors; D014481:United States / Q000453:epidemiology
chemical_list: D001565:Benzoates; D015415:Biomarkers; D010575:Pesticides; D011722:Pyrethrins; C017618:3-phenoxybenzoic acid