Facing an especially cold winter this year, many people are attempting to stay warm by taking long, hot showers or baths, a practice that could increase the risks of cancer if done in an enclosed space, doctors said yesterday.
While many people enjoy taking a hot bath or shower, few are aware of the health risks associated with the activity, they said.
Chiang Shou-shan (江守山), a nephrologist at Shin-Kong Wu Ho-Su Memorial Hospital, said taking long, hot showers or baths for more than 20 minutes in a confined space with no circulation of fresh air could have a negative impact on a person’s health, because small amounts of chlorine and trihalomethanes (THM) found in tap and drinking water become volatile when the water is heated.
The chemicals can enter the body through the respiratory -system as a person breathes in the steam, Chiang said.
The longer the hot shower, the more THMs a person inhales, Chiang said.
Increasing shower time from five minutes to 10 minutes, for example, could cause a person to breathe in four to five times more THMs, he said.
THM is a byproduct of the small amount of chlorine added to the water supply by municipal authorities as a disinfectant. However, overexposure to THMs can increase the risks of developing various forms of cancer, including colon cancer, pancreatic cancer and bladder cancer.
The chemicals are also harmful to the liver and kidneys, and could increase the risks of miscarriage in women, he said.
Lin Ja-liang (林杰樑), a specialist in clinical toxicology at Chang Gung Memorial Hospital in New Taipei City’s (新北市) Linkou District (林口), said that by limiting hot showers to less than 10 minutes and reducing the temperature of the water, a person could drastically decrease the amount of THMs absorbed by the body.
Turning on the fan in the bathroom to allow for air circulation was also a good way to avoid breathing in too many toxins from a steamy shower, he said.