As summer approaches we’re digging out our goggles, inner tubes and various pool toys in expectation of lazy days spent at our local swimming pool. So when I learned that 20% of Olympic swimmers have asthma and the possible culprit is exposure to chlorine, it gave me pause.
The problem isn’t the chlorine, but what chlorine turns into when combined with organics. The organics are contributed by bathers in the pool in the form of sweat, dander, urine and other organics. The chlorine reacts with the organics and produces nitrogen trichloride, aldehydes, halogenated hydrocarbons, chloroform, trihalomethanes and chloramines. If these sound like dangerous chemicals, they are. During the Olympic Games held in Australia, it was reported that more than one-quarter of the American swim team suffered from some degree of asthma.
Since we live in an area that already has high rates of pediatric asthma, due to our proximity to a major worldwide port, I began to worry. My son, who suffered from asthma as a toddler, either outgrew it or ….stopped suffering from it when we moved 15 miles further from the port.
But, could a summer by the pool bring it back?
In Brussels, researchers followed 226 otherwise healthy school children, mean age 10, to determine how much time they spent around indoor swimming pools, and then analyzed the condition of their lungs.
“These findings suggest that the increasing exposure to chlorine-based disinfectants used in swimming pools and their by-products might be an unsuspected risk factor in the rising incidence of childhood asthma and allergic diseases,” noted Dr. Simone Carbonnelle, who conducted the study.
So does this mean we need to limit our time in the water this year?
Studies in the United States, Canada and Norway have linked chlorine byproducts in ordinary tap water to higher risks of miscarriages and stillbirths in pregnant women and increased incidences of bladder and colon cancer. Of disturbing news for indoor swimming pool patrons are studies that show much higher levels of these chemicals are found in swimmers. And the highest levels are found in the most active swimmers.
The heightened risk is linked to exposure to a contaminant found in chlorinated water called trihalomethanes (THMs) which forms when chlorine reacts with organic material. THMs are a widely recognized carcinogen.
While regulation changes in Canada and the United States have put tighter restrictions on the levels of THMs allowed in tap water, no such regulations exist for swimming pool water.
The greatest exposure to these types of chemicals seems to come from patronizing indoor swimming pool, less an issue in the summer months, but hours and hours spent in chlorinated water inside or out can be a hazard. One solution is to seek out or install, if you have your own pool, a system that treats water with ozone gas or ultra violet light. This system has been used in pools in Europe for over 40 years…one would guess that it shouldn’t be long before U.S. pools start to adopt the technology.
In the meantime, I intend to seek out pools using one of the new technologies or natural salt water and/or similar systems. Unfortunately I found no easy way to do this beyond calling up the local pool and asking.
Photo Credit: Peasaap at Flickr under Creative Commons License