title: Water consumption and use, trihalomethane exposure, and the risk of hypospadias.
abstract: OBJECTIVE
  Hypospadias is a congenital anomaly that affects up to 70 in 10 000 males. Ingestion of drinking-water-disinfection byproducts such as trihalomethanes (THMs) has been associated with hypospadias in a small sample. We examined risk of hypospadias and exposure to THMs through water consumption and use.
  
  
  METHODS
  Between September 2000 and March 2003, we interviewed mothers of 471 boys with hypospadias and 490 controls in southeast England about maternal water consumption, dishwashing, showering, bathing and swimming. We obtained residential THM concentrations from the water companies and linked them by using Geographical Information Systems, which provided data on 468 case-subjects and 485 controls.
  
  
  RESULTS
  THM exposures, except for ingestion of ≥ 6 μg/day of bromodichloromethane (odds ratio [OR]: 1.65 [95% confidence interval (CI): 1.02-2.69]), were not associated with risk of hypospadias. Elevated risk of hypospadias was associated with estimates of consumption of cold tap water at home (OR: 1.71 [95% CI: 1.07-2.76]), total water (OR: 1.70 [95% CI: 1.09-2.67]), bottled water (OR: 1.64 [95% CI: 1.09-2.48]), and total fluid (OR: 1.55 [95% CI: 1.01-2.39]) for the highest versus the lowest categories; the first 2 showed dose-response trends.
  
  
  CONCLUSIONS
  Evidence for an association between maternal water consumption and risk of hypospadias did not seem to be explained by THM exposure. Factors that influence maternal water consumption or other contaminants in tap or bottled water might explain this finding. It is important that women maintain an adequate fluid intake during pregnancy.
authors.affiliation: Department of Epidemiology and Biostatistics and MRC-HPA Centre for Environment and Health, Imperial College London, London, United Kingdom.
authors.forename: Nina
authors.initials: N
authors.lastname: Iszatt
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Nieuwenhuijsen
authors.forename: Paul
authors.initials: P
authors.lastname: Nelson
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
authors.forename: Mireille B
authors.initials: MB
authors.lastname: Toledano
mesh_terms: D016022:Case-Control Studies; D002675:Child, Preschool; D004326:Drinking / Q000502:physiology; D005260:Female; D006801:Humans; D007021:Hypospadias / Q000139:chemically induced / Q000175:diagnosis* / Q000453:epidemiology*; D007223:Infant; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000139:chemically induced / Q000175:diagnosis* / Q000453:epidemiology*; D012307:Risk Factors; D022882:Trihalomethanes / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D022882:Trihalomethanes