No 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

Hormonal factors, possibly related to reproductive characteristics, may play a role in the risk of bladder cancer among women. To study this, we investigated the effects of reproductive factors on female bladder cancer risk. Information on reproductive and other risk factors was gathered in personal interviews from 152 female cases and 166 matched controls from 18 hospitals in five regions of Spain during 1998-2001. Logistic regression was used to estimate the association between bladder cancer and reproductive factors, including ever-parous status, age at first live birth, age at last live birth, age at menarche, age at menopause, menopausal status, and duration of menstruation. After adjustment for age, smoking, and high-risk occupation, ever-parous women were at decreased risk relative to nulliparous women (odds ratio = 0.43, 95% confidence interval = Correspondence to: An-Tsun Huang, huangan@mail.nih.gov. NIH Public Access Author ManuscriptCancer Causes Control. Author manuscript; available in PMC 2011 January 1. NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript 0.21-0.87). There was no consistent pattern in risk with the age-or duration-related reproductive factors (e.g., age at first live birth, age at last live birth, age at menarche, age at menopause, menopausal status, and duration of menstruation) that we evaluated. Women have a lower risk of bladder cancer than men, and hormonal factors related to childbearing may play a role.

Trihalomethanes (THMs) are suspected carcinogens and reproductive toxicants commonly found in chlorinated drinking water. This study investigates THM formation during the preparation of beverages and foods using chlorinated drinking water. A total of 11 foods and 17 beverages were tested. Under the experimental conditions, each food and beverage formed THMs, primarily chloroform, although low or trace levels of brominated THMs were also detected. Tea formed the highest THM levels (e.g., chloroform levels from 3 to 67 microg l(-1)), followed by coffee (from 3 to 13 microg l(-1)), rice (9 microg l(-1)), soups (from 0.4 to 3.0 microg l(-1)), vegetables (<1 microg l(-1)), and baby food (<0.7 microg l(-1)). Chloroform formation with instant tea, used as a highly reproducible model system, increased with free chlorine concentration, decreased with higher food (tea) concentration, and was unaffected by reaction (steeping) time and bromide ion concentration. These findings indicate that chlorine-food reactions are fast, but that formation decreases as the chlorine demand of the food system increases. THMs are formed in the preparation and cooking of a wide variety of foods if free chlorine is present, and our results suggest that tea can be a significant source of exposure to THMs.

Results suggest that past policies have been effective in reducing smoking rates, but there is also a strong potential for future policies consistent with the Framework Convention on Tobacco Control. When specific taxes are increased to 70% of retail price, strong smoke-free air laws, youth access laws and marketing restrictions are enforced, stronger health warnings are implemented, and cessation treatment and media campaigns are supported, smoking prevalence and SADs will fall substantially in European countries.