Showering and bathing in chlorinated water may expose us to even more chlorine and its byproducts than drinking this disinfected water. You should read more about the dangers of showering in chlorinated water.
While our bodies can filter out much of the chlorine from our drinking water, the THMs and other disinfectant byproducts we inhale during showers and baths may be much more harmful, since the chlorine gas we inhale enters directly into our blood stream. Therefore, even if you filter your drinking water, the amount of toxins you are exposed to from your daily shower or bath, through inhalation or skin absorption, may be cause for greater concern.
Research has demonstrated that the cancer risk associated with chlorinated water may actually be due to showering and bathing, rather than drinking the disinfected water. This suggests that many health risks of chlorine may be specifically related to dermal and inhalation exposure. In fact, the chloroform dose from a single, ten minute shower is equal to, and possibly greater than, that from the average two liters of water ingestion on a daily basis.