It has been known for some time that long-term exposure to Trihalomethanes (THMs) which are disinfection by-products (DBPs) in drinking water, has been consistently associated with increased bladder cancer risk.
Research carried out by a team from the National Institute of Environmental Health Sciences in Europe, shows that a percentage of bladder cancers in Ireland and some other EU countries could be attributed to the use of disinfectant products like chlorine in drinking water. According to the research, Chlorine is the most widely used disinfectant used in the purification of drinking water. However, in some situations, free chlorine reacts with organic compounds in water which then creates byproducts including THM’s (Trihalomethanes), which are being associated with bladder cancer.
Countries showing the highest levels of bladder cancer cases linked to THM’s were Cyprus, Malta, Ireland, Spain and Greece. Countries with the lowest rate of bladder cancer were Denmark and Holland. There is no unequivocal evidence that THMs cause bladder cancer only a link and it should be noted that the health benefits of water disinfection and chlorination far outweigh a small increase in the risk of bladder cancer.
As Ireland is one of nine countries that exceed current average THM levels in drinking water, it could lead to an increase in the number of bladder cancer cases unless measures are adopted to optimise water treatment, disinfection, and distribution or other measures, without micro-biologically compromising the quality of drinking water.
For families and households worried about THMs or other chemical contaminants in their drinking water, a quality under-sink water filter or filtration system will purify the water for drinking and provide long term protection and peace of mind.