title: Bladder cancer and exposure to water disinfection by-products through ingestion, bathing, showering, and swimming in pools.
abstract: Bladder cancer has been associated with exposure to chlorination by-products in drinking water, and experimental evidence suggests that exposure also occurs through inhalation and dermal absorption. The authors examined whether bladder cancer risk was associated with exposure to trihalomethanes (THMs) through ingestion of water and through inhalation and dermal absorption during showering, bathing, and swimming in pools. Lifetime personal information on water consumption and water-related habits was collected for 1,219 cases and 1,271 controls in a 1998-2001 case-control study in Spain and was linked with THM levels in geographic study areas. Long-term THM exposure was associated with a twofold bladder cancer risk, with an odds ratio of 2.10 (95% confidence interval: 1.09, 4.02) for average household THM levels of >49 versus < or =8 micro g/liter. Compared with subjects not drinking chlorinated water, subjects with THM exposure of >35 micro g/day through ingestion had an odds ratio of 1.35 (95% confidence interval: 0.92, 1.99). The odds ratio for duration of shower or bath weighted by residential THM level was 1.83 (95% confidence interval: 1.17, 2.87) for the highest compared with the lowest quartile. Swimming in pools was associated with an odds ratio of 1.57 (95% confidence interval: 1.18, 2.09). Bladder cancer risk was associated with long-term exposure to THMs in chlorinated water at levels regularly occurring in industrialized countries.
authors.affiliation: Centre for Research in Environmental Epidemiology, Municipal Institute of Medical Research, Barcelona, Spain.
authors.forename: Cristina M
authors.initials: CM
authors.lastname: Villanueva
authors.forename: Kenneth P
authors.initials: KP
authors.lastname: Cantor
authors.forename: Joan O
authors.initials: JO
authors.lastname: Grimalt
authors.forename: Nuria
authors.initials: N
authors.lastname: Malats
authors.forename: Debra
authors.initials: D
authors.lastname: Silverman
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardon
authors.forename: Reina
authors.initials: R
authors.lastname: Garcia-Closas
authors.forename: Consol
authors.initials: C
authors.lastname: Serra
authors.forename: Alfredo
authors.initials: A
authors.lastname: Carrato
authors.forename: Gemma
authors.initials: G
authors.lastname: Castaño-Vinyals
authors.forename: Ricard
authors.initials: R
authors.lastname: Marcos
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Rothman
authors.forename: Francisco X
authors.initials: FX
authors.lastname: Real
authors.forename: Mustafa
authors.initials: M
authors.lastname: Dosemeci
authors.forename: Manolis
authors.initials: M
authors.lastname: Kogevinas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001494:Baths / Q000009:adverse effects*; D004203:Disinfection; D004326:Drinking; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D013551:Swimming Pools; D001749:Urinary Bladder Neoplasms / Q000453:epidemiology / Q000209:etiology*; D018508:Water Purification