title: Exposure to ambient PM10and NO2and the incidence of attention-deficit hyperactivity disorder in childhood.
abstract: Epidemiological studies have implicated air pollution in the causation of neurodevelopmental disorders, including attention-deficit hyperactivity disorder (ADHD), but definitive evidence of this linkage is lacking.
  
  
  
  We examined the association between cumulative exposure to air pollutants from birth to diagnosis, particularly particulate matter of <10μm (PM10) and nitric dioxide (NO2), and childhood ADHD.
  
  
  
  We used the National Health Insurance Service-National Sample Cohort (2002-2012), a population-wide health insurance claims dataset. A total of 8936 infants (age 0) born between January 2002 and December 2002 were followed-up for a 10-year period (2003-2012). ADHD was defined as per ICD-10 code F90.0. Exposure levels of PM10and NO2were extrapolated using geographic information systems and collated with the subjects' administrative district code, and individual exposure levels assigned. Hazard ratios (HRs) were calculated for the development of ADHD, after adjusting for gender, metropolitan area, income, and history of diseases.
  
  
  
  During the study period, ADHD occurred in 314 subjects (3.5%). With the increase in 1μg/m3of air pollutants, the HRs of childhood ADHD were 1.18 (95% CI: 1.15-1.21) in case of PM10and 1.03 (95% CI: 1.02-1.04) in case of NO2. Compared with infants with the lowest tertile of PM10or NO2exposure, those with the highest tertile of PM10(HR=3.88; 95% CI: 2.87-5.23) or NO2(HR=2.10; 95% CI, 1.54-2.85) exposure had a 2 to 3 fold increased risk for ADHD.
  
  
  
  Exposure to PM10and NO2was associated with the incidence of ADHD in childhood.
authors.affiliation: Institute of Health and Environment, School of Public Health, Seoul National University, Seoul, Republic of Korea.
authors.forename: Jin-Young
authors.initials: JY
authors.lastname: Min
authors.affiliation: Department of Preventive Medicine, College of Medicine, Seoul National University, Seoul, Republic of Korea. Electronic address: minkb@snu.ac.kr.
authors.forename: Kyoung-Bok
authors.initials: KB
authors.lastname: Min
mesh_terms: D000393:Air Pollutants / Q000633:toxicity*; D001289:Attention Deficit Disorder with Hyperactivity / Q000139:chemically induced / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009585:Nitrogen Dioxide / Q000633:toxicity*; D052638:Particulate Matter / Q000633:toxicity*; D056910:Republic of Korea / Q000453:epidemiology
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D009585:Nitrogen Dioxide
keywords: Children's health; Neurodevelopmental disorder; Nitric dioxide; Particulate matter