RODALE NEWS, EMMAUS, PA—Summer's getting close, which means swimming season is upon us. Whether you're a dedicated lap swimmer or a parent looking for something to occupy your kids on summer vacation, chances are you'll be spending a lot of time poolside over the next few months. Just be sure to shower first. Public health officials are getting increasingly concerned over the public's lackadaisical attitude towards personal hygiene and pools, not just because it increases swimmers' risks of contracting serious waterborne illnesses but also because our "bodily secretions" react with chlorine to form hazardous byproducts that can cause allergies, asthma, and possibly even cancer.
An article in this month's issue of Environmental Science & Technology examined the evidence surrounding chlorine's effectiveness, and its potential for harm, and what the public can and needs to do to keep safe.
THE DETAILS: Every time we go swimming, we add sweat, urine, invisible fecal matter, lotions, and sunscreens to an already soupy mix of chemicals and bacteria in pool water from other swimmers. All of those react with existing organic matter in the pool and with the chlorine used to disinfect the water and keep you safe, and those reactions produce potentially toxic disinfection by-products, including chloramines, which have been linked to lung and skin irritation, allergies, and asthma, and trihalomethanes, which have been linked to bladder and liver cancer. Yet the by-products created from chlorine disinfection could be no worse than the diarrheal diseases you can catch from improperly treated water, specifically shigellosis, E. coli, cryptosporidiosis, and giardiasis. And next to nothing is known about alternatives to chlorine disinfectants—UV light, ozonation, and copper/silver treatments—when it comes to either their efficacy or any potential disinfection by-products.
Compounding the problem, most of us take a rather blasé attitude toward pools and swimming. We assume that the operator of the pool has followed basic treatment protocols, and that our bodies are clean enough not to contribute to the problem. But that's not always the case. There are no national uniform standards for maintaining pools, and requirements for preventing or responding to recreational water illnesses change city to city and state to state, writes Judy LaKind, PhD, the paper's author and associate professor at the University of Maryland School of Medicine.