Social class makes no difference to water contamination risk

Wealthy, well educated people who choose to drink bottled water rather than water from public supplies may be no less exposed to potentially cancer-causing water contaminants, according to new research published in BioMed Central's open access journal Environmental Health.

As part of the EPICURO national bladder cancer study, researchers from all over Spain quizzed 1,270 individuals about their water use and consumption in an effort to discover whether social class has any bearing on exposure to common water disinfection byproducts. High levels of trihalomethanes (THM), chemicals formed in chlorinated water, have been implicated as a possible risk factor for cancer and can be ingested through public drinking water supplies, or absorbed through the skin in baths, showers, and public swimming pools.

The CREAL (Centre for Research in Environmental Epidemiology) research team found that richer people with higher levels of schooling consumed more bottled water than those less educated. Dr Gemma Castaño-Vinyals, who led the investigation, said, "People with more money and more education may think that they're reducing their risk of exposure to water contaminants by drinking bottled water. However, despite being apparently cleaner and taking more exercise – a result of taking more frequent and longer baths, and using swimming pools more often – they are actually increasing their risk of THM exposure.

"It must be said that, the risk of these contaminants causing bladder cancer is small, and findings from this research may help us to understand water use patterns in the context of cancer prevention."