Trihalomethanes (THMs) are among the most dangerous chemical compounds that find their way into the water supply. THM contamination is very common, because these substances are a byproduct formed when chlorine is added to drinking water. THMs are known to be carcinogens, and are closely associated with the occurrence of several different types of cancer. Additionally, these substances cause problems with the functioning of the nervous system, the liver, and the kidneys. Ingestion of these substances can also contribute to miscarriages.
Even though the dangers of THMs are well-documented and the substance is present in the vast majority of drinking water, many home water filtration systems are not designed to remove these substances from the water supply. For example, Brita water filters and PUR water filters do not remove THMs from water. Both Aquasana and Amway water filters are proven to be effective at removing more than 99% of THMs from water. Kenmore and Culligan water filters also filter out large percentages of these substances.