Those who swim regularly in pools with chlorinated water need to take care as Spanish researchers have warned that regular contact with chlorinated water enhances the risk of bladder cancer.

"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," researchers said.
Source-Medindia