Avoid Overly-Chlorinated Drinking Water

March 25, 2023

Chlorine is added to most water supplies to kill bacteria. However, when it reacts with organic matter (like leaves), it produces harmful trihalomethanes or THMs. THMs are chemicals that studies have shown to be linked to an increased risk of miscarriage, bladder and rectal cancers, and birth defects in people who have been exposed to it. High levels of THMs may increase the risk of miscarriage.

Filtration is one way of avoiding chlorine and THMs. Carbon-activated water filters place on showerheads and faucets remove THMs – distillers do not removed THMs. You can also dissipate THMs from tap water by leaving it in an open container in the refrigerator for a few hours, or boiling it for one minute. (Warning: If you have lead contaminated water, boiling will increase the contamination levels.) Installing a water filter is a cheap and effective way to obtain clean water even compared to bottled water that is less regulated than tap water.

According to National Sanitation Federation, NSF Standard 42 is used on filters that can remove contaminants that reduce aesthetic quality (taste, smell, color), such as aluminum, chlorine, iron and sediment. NSF Standard 53 is the most comprehensive and used for filters that remove most pesticides, VOCs, cysts, fluoride, most heavy metals and THMs.