title: Manganese exposure from drinking water and children's classroom behavior in Bangladesh.
abstract: BACKGROUND
  Evidence of neurological, cognitive, and neuropsychological effects of manganese (Mn) exposure from drinking water (WMn) in children has generated widespread public health concern. At elevated exposures, Mn has been associated with increased levels of externalizing behaviors, including irritability, aggression, and impulsivity. Little is known about potential effects at lower exposures, especially in children. Moreover, little is known regarding potential interactions between exposure to Mn and other metals, especially arsenic (As).
  
  
  OBJECTIVE
  We conducted a cross-sectional study of 201 children to investigate associations of Mn and As in tube well water with classroom behavior among elementary school children, 8-11 years of age, in Araihazar, Bangladesh.
  
  
  METHODS
  Data on exposures and behavioral outcomes were collected from the participants at the baseline of an ongoing longitudinal study of child intelligence. Study children were rated by their school teachers on externalizing and internalizing items of classroom behavior using the standardized Child Behavior Checklist-Teacher's Report Form (CBCL-TRF).
  
  
  RESULTS
  Log-transformed WMn was positively and significantly associated with TRF internalizing [estimated β = 0.82; 95% confidence interval (CI), 0.08-1.56; p = 0.03], TRF externalizing (estimated β = 2.59; 95% CI, 0.81-4.37; p =0.004), and TRF total scores (estimated β = 3.35; 95% CI, 0.86-5.83; p = 0.008) in models that adjusted for log-transformed water arsenic (WAs) and sociodemographic covariates. We also observed a positive monotonic dose-response relationship between WMn and TRF externalizing and TRF total scores among the participants of the study. We did not find any significant associations between WAs and various scales of TRF scores.
  
  
  CONCLUSIONS
  These observations reinforce the growing concern regarding the neurotoxicologic effects of WMn in children.
authors.affiliation: Department of Environmental Health Sciences, Columbia University Mailman School of Public Health, New York, New York, USA.
authors.forename: Khalid
authors.initials: K
authors.lastname: Khan
authors.forename: Pam
authors.initials: P
authors.lastname: Factor-Litvak
authors.forename: Gail A
authors.initials: GA
authors.lastname: Wasserman
authors.forename: Xinhua
authors.initials: X
authors.lastname: Liu
authors.forename: Ershad
authors.initials: E
authors.lastname: Ahmed
authors.forename: Faruque
authors.initials: F
authors.lastname: Parvez
authors.forename: Vesna
authors.initials: V
authors.lastname: Slavkovich
authors.forename: Diane
authors.initials: D
authors.lastname: Levy
authors.forename: Jacob
authors.initials: J
authors.lastname: Mey
authors.forename: Alexander
authors.initials: A
authors.lastname: van Geen
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Graziano
mesh_terms: D001459:Bangladesh; D002648:Child; D002652:Child Behavior / Q000187:drug effects*; D060766:Drinking Water / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008345:Manganese / Q000633:toxicity*; D014873:Water Pollutants / Q000633:toxicity*
chemical_list: D060766:Drinking Water; D014873:Water Pollutants; D008345:Manganese