Chlorination Byproducts and Nitrate in Drinking Water and Risk for Congenital Cardiac Defects

• Published in: Environmental research Vol. 89; no. 2; pp. 124 - 130
• Main Authors: Cedergren, Marie I., Selbing, Anders J., Löfman, Owe, Källen, Bengt A.J.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01-06-2002; Elsevier
• Subjects: Adult; Arbetsmedicin och miljömedicin; Biological and medical sciences; cardiac defects; chlorination; Chlorine Compounds - adverse effects; Dental Disinfectants - adverse effects; Disinfectants - adverse effects; Disinfectants - chemistry; drinking water; Environmental Health and Occupational Health; Female; Food toxicology; Health Sciences; Heart Defects, Congenital - epidemiology; Heart Defects, Congenital - etiology; Humans; Hälsovetenskap; Incidence; Infant, Newborn; Male; Medical and Health Sciences; Medical sciences; MEDICIN; Medicin och hälsovetenskap; MEDICINE; nitrate; Nitrates - adverse effects; Odds Ratio; Oxides - adverse effects; Pregnancy; Registries; Retrospective Studies; Risk Assessment; Sweden; Toxicology; trihalomethane; Trihalomethanes - adverse effects; Water Pollutants - adverse effects; Water Purification; Water Supply; Sweden; cardiac defects; trihalomethane; drinking water; nitrate; chlorination; Heart; Human; Drinking water treatment; Chlorination; Congenital; Toxicity; Trihalomethane; Nitrates; Epidemiology; Malformation; Heart disease; Teratogen; By product; Public health
• ISSN: 0013-9351; 1096-0953; 1096-0953
• DOI: 10.1006/enrs.2001.4362

Drinking water disinfection byproducts have been associated with an increased risk for congenital defects including cardiac defects. Using Swedish health registers linked to information on municipal drinking water composition, individual data on drinking water characteristics were obtained for 58,669 women. Among the infants born, 753 had a cardiac defect. The risk for a cardiac defect was determined for ground water versus surface water, for different chlorination procedures, and for trihalomethane and nitrate concentrations. Ground water was associated with an increased risk for cardiac defect when crude rates were analyzed but after suitable adjustments this excess rate was found to be determined by chlorination procedures including chlorine dioxide. Chlorine dioxide appears itself as an independent risk factor for cardiac defects (adjusted odds ratio 1.61 (95%CI 1.00–2.59)). The risk for cardiac defects increased with increasing trihalomethane concentrations (P=0.0005). There was an indicated but statistically nonsignificant excess risk associated with nitrate concentration. The individual risk for congenital cardiac defect caused by chlorine dioxide and trihalomethanes is small but as a large population is exposed to public drinking water, the attributable risk for cardiac defects may not be negligible.