Municipal water companies need to dose the water with a disinfectant that kills pathogenic bacteria such as e-coli—usually it’s chlorine or chlorine mixed with small amounts of ammonia which react to form chloramine (also called combined chlorine). The Environmental Protection Agency requires that a some of the disinfectant, called a “residual”, remain in the water as it’s being delivered to our homes. They do this every day after testing the level of bacteria. Some days they need put in a heavier dose of chlorine because the bacteria count is high.
One of by-products of the disinfectant, whether it’s chlorine or chloramine, are trihalomethanes (THM). It turns out that chloramine does not produce as much of these contaminants as chlorine.
Chloramine is toxic to fish and amphibians because it comes into direct contact with their bloodstream. For this same reason, people on dialysis machines must remove the chloramine because the water also comes into direct contact with the bloodstream.
While chloramines are generally not considered a health concern for humans, they can introduce an undesired taste and odor to the water. The most effective non-chemical method of removing chloramines is by running the water through activated carbon.
Long-term exposure to THMs has been linked to increased risk of problems in infant-birth delivery, certain diseases of the heart, and an increased risk of cancer, especially bladder cancer. The EPA sets a maximum level of Total THMs for drinking water to 80 parts per billion (µg/L).
The best solution for reducing the amount of THMs in city water is to use an activated charcoal filter. Some filtration units also include ion exchange and adsorption in addition to the activated charcoal filter.
Here’s a great demonstration on just how quickly chlorine-infused water can enter our bodies through our skin:
If you would like to explore a variety of treatment solutions, from whole-house to under-the-counter point-of-use filtration systems, we can help you.
Even before you do that, you may want to check out this web site—just click on the button below. Come back to us after that if you want more help.