Ontology highlight
ABSTRACT: Background
Ingestion of disinfection byproducts has been associated with bladder cancer in multiple studies. Although associations with other routes of exposure have been suggested, epidemiologic evidence is limited.Objectives
We evaluated the relationship between bladder cancer and total, chlorinated, and brominated trihalomethanes (THMs) through various exposure routes.Methods
In a population-based case–control study in New England (n=(1,213) cases; n=(1,418) controls), we estimated lifetime exposure to THMs from ingestion, showering/bathing, and hours of swimming pool use. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression adjusted for confounders.Results
Adjusted ORs for bladder cancer comparing participants with exposure above the 95th percentile with those in the lowest quartile of exposure (based on the distribution in controls) were statistically significant for average daily intake mg/d of total THMs [OR=1.53 (95% CI: 1.01, 2.32), p-trend=0.16] and brominated THMs [OR=1.98 (95% CI: 1.19, 3.29), p-trend=0.03]. For cumulative intake mg, the OR at the 95th percentile of total THMs was 1.45 (95% CI: 0.95, 2.2), p-trend=0.13; the ORs at the 95th percentile for chlorinated and brominated THMs were 1.77 (95% CI: 1.05, 2,.99), p-trend=0.07 and 1.78 (95% CI: 1.05, 3.00), p-trend=0.02, respectively. The OR in the highest category of showering/bathing for brominated THMs was 1.43 (95% CI: 0.80, 2.42), p-trend=0.10. We found no evidence of an association for bladder cancer and hours of swimming pool use.Conclusions
We observed a modest association between ingestion of water with higher THMs (>95th?percentile?vs.<25th?percentile) and bladder cancer. Brominated THMs have been a particular concern based on toxicologic evidence, and our suggestive findings for multiple metrics require further study in a population with higher levels of these exposures. Data from this population do not support an association between swimming pool use and bladder cancer. https://doi.org/10.1289/EHP89.
SUBMITTER: Beane Freeman LE
PROVIDER: S-EPMC5743617 | biostudies-literature | 2017 Jun
REPOSITORIES: biostudies-literature
Environmental health perspectives 20170621 6
<h4>Background</h4>Ingestion of disinfection byproducts has been associated with bladder cancer in multiple studies. Although associations with other routes of exposure have been suggested, epidemiologic evidence is limited.<h4>Objectives</h4>We evaluated the relationship between bladder cancer and total, chlorinated, and brominated trihalomethanes (THMs) through various exposure routes.<h4>Methods</h4>In a population-based case–control study in New England (<i>n</i>=(1,213) cases; <i>n</i>=(1,4 ...[more]