title: Relation of trihalomethane concentrations in public water supplies to stillbirth and birth weight in three water regions in England.
abstract: We investigated the association between total trihalomethanes (TTHMs) and risk of stillbirth and low and very low birth weight in three water regions in England, 1992-1998; associations with individual trihalomethanes (THMs) were also examined. Modeled estimates of quarterly TTHM concentrations in water zones, categorized as low (< 30 microg/L), medium (30-59 microg/L), or high (> or = 60 microg/L), were linked to approximately 1 million routine birth and stillbirth records using maternal residence at time of birth. In one region, where there was a positive socioeconomic deprivation gradient across exposure categories, there was also a positive, significant association of TTHM with risk of stillbirth and low and very low birth weight. Overall summary estimates across the three regions using a random-effects model to allow for between-region heterogeneity in exposure effects showed small excess risks in areas with high TTHM concentrations for stillbirths [odds ratio (OR) = 1.11; 95% confidence interval (CI), 1.00-1.23), low birth weight (OR = 1.09; 95% CI, 0.93-1.27), and very low birth weight (OR = 1.05; 95% CI, 0.82-1.34). Among the individual THMs, chloroform showed a similar pattern of risk as TTHM, but no association was found with concentrations of bromodichloromethane or total brominated THMs. Our findings overall suggest a significant association of stillbirths with maternal residence in areas with high TTHM exposure. Further work is needed looking at cause-specific stillbirths and effects of other disinfection by-products and to help differentiate between alternative (noncausal) explanations and those that may derive from the water supply.
authors.affiliation: Department of Epidemiology and Public Health, Faculty of Medicine, Imperial College London, London, United Kingdom.
authors.forename: Mireille B
authors.initials: MB
authors.lastname: Toledano
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Nieuwenhuijsen
authors.forename: Nicky
authors.initials: N
authors.lastname: Best
authors.forename: Heather
authors.initials: H
authors.lastname: Whitaker
authors.forename: Peter
authors.initials: P
authors.lastname: Hambly
authors.forename: Cornelis
authors.initials: C
authors.lastname: de Hoogh
authors.forename: John
authors.initials: J
authors.lastname: Fawell
authors.forename: Lars
authors.initials: L
authors.lastname: Jarup
authors.forename: Paul
authors.initials: P
authors.lastname: Elliott
mesh_terms: D000328:Adult; D004739:England / Q000453:epidemiology; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D018811:Maternal Exposure; D016017:Odds Ratio; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D022882:Trihalomethanes / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis; D018508:Water Purification; D014881:Water Supply / Q000032:analysis
chemical_list: D022882:Trihalomethanes; D014874:Water Pollutants, Chemical