Not many people actually enjoy the taste or smell of chlorinated drinking water, but did you know that recent studies have unofficially linked birth defects to chlorinated drinking water? It seems as though a pregnant woman’s exposure to chlorine byproducts called trihalomethanes (THMs) in drinking water, bath water, etc. may play a part in causing serious health problems for her unborn child:

“Expectant mothers can expose themselves to the higher risk by drinking the water, swimming in chlorinated water, taking a bath or shower, or even by standing close to a boiling kettle, say researchers.

The finding, based on an analysis of nearly 400,000 infants, is the first that links by-products of water chlorination – chemicals known as trihalomethanes, or THMs – to three specific birth defects.

Exposure to high levels of THMs substantially increased the risk of holes in the heart, cleft palate and anencephalus, which results in the absence of a major portion of the brain, skull, and scalp.” ( source )

Most water systems chlorinate the water they provide in an effort to eliminate parasites and bacteria in drinking water which could lead to waterborne ailments and illnesses.

Not sure if your water contains THMs? Maybe the next few statements will help:

  • Public water supplies that use free chlorine as their primary disinfectant (instead of chloramines) may contain THMs. The compounds form when free chlorine molecules lock horns with a biological contaminant during the disinfection process.
  • Public water supplies that use chloramines as their primary disinfectant (instead of free chlorine) typically do not contain THMs. However it should be noted that these water systems do periodically ‘burn’ their water lines with free chlorine in an effort to get rid of any biofilm that has formed and THMs do result from those ‘burn’ sessions.

Still unsure as to whether or not your drinking water may contain THMs? You have three options:

  1. Call your local water authority and ask them if they use free chlorine as the primary disinfectant or chloramines. If so, then your water most likely contains chloramines.
  2. Have your water tested by a certified water testing professional.
  3. Use reliable drinking water test kits for both free chlorine AND total chlorine.