THMs are trihalomethanes, chemical compounds that are created when chlorine is added to the water. The chlorine reacts with organic matter in the water to create VOCs (volatile organic compounds) and THMs (trihalomethanes).
Why is chlorine added to the water?
The city adds chlorine to the water supply to ensure that any bacteria that may be present are killed and the water is *safe* for consumption.
What effect can THMs have on my health?
Studies have shown that exposure/intake of THMs over time lead to a higher risk of bladder and colon cancer. It is especially recommended that pregnant women consider their intake and exposure to THMs, because they have been found to be a contributing factor to birth outcomes, such as miscarriage, birth defects, and low birth weight.
Can THMs only affect me through my drinking water?
No. THMs can be absorbed by the skin when bathing/washing in untreated city water, or be inhaled during regular water-related activities, such as washing dishes.
How can I avoid my exposure to THMs?
You can install a water filter designed to remove THMs from the water – you will be able to tell if it is indicated on the filter that it meets NSF Standard 53. To increase your protection from contaminants in the water, installing a reverse osmosis drinking water system is always recommended.