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Originally published September 29 2010

Chlorinated Indoor Swimming Pools are Hazardous to Your Health

by Amelia Bentrup

(NaturalNews) While indoor swimming is an increasingly popular activity, not many people are aware of the health hazards associated with exposure to pool chemicals and chemical by-products. A recent study published September 2010 in Environmental Health Perspectives examined 49 non-smokers both before and after 40 minutes of swimming in an indoor chlorinated swimming pool.

Researchers examined various biomarkers for cancer in the subjects' blood, urine and exhaled air. One of the markers for cancer showed a five-fold increase after swimming. Researcher Manolis Kogevinas, MD, PhD is a professor of epidemiology at the Centre for Research in Environmental Epidemiology in Barcelona. He states, "This doesn't mean at all that swimmers have a five times increased cancer risk. It simply means that after swimming for 40 minutes in a chlorinated pool, you get an increase in this marker in the blood that in other studies has been associated with future cancer risk."

A second study, also published September 2010 in Environmental Health Perspectives, looked at changes in respiratory biomarkers before and after swimming. They found a slight increase in one blood biomarker, known as CC16. This biomarker is associated with an increase in lung permeability. Kogevinas states this increase can be explained by both the exercise and the exposure to chlorine by-products.

Previous studies have also shown an increase in lung permeability after swimming. A June 2003 study conducted at Catholic University of Louvain in Belgium showed a relationship between the amount of time school-age children spend around chlorinated swimming pools and lung permeability.

When pool chemicals such as chlorine interact with sweat, skin cells, dander and other organic substances found in swimming pools, chemical reactions occur. These chemical reactions produce DBPs or disinfection by-products. These DBPs are hazardous to your health. It has been known for several years that asthma is an occupational hazard for indoor lifeguards and swim instructors.

Children are especially vulnerable to the damaging effects of DBPs. A July 2010 study led by Alfred Bernard and published in the European Respiratory Journal suggests that infant exposure to indoor, chlorinated swimming pools predisposes children to bronchiolitis. This makes them more vulnerable to asthma and allergies later in life.

So, does all this mean you should avoid swimming pools? Not according to Kogevinas. "We do not say stop swimming. We should keep a clear message that swimmers should keep swimming." Proper pool maintenance and following pool rules, such as showering before entering and not urinating in the pool can help. Alfred Bernard suggests using pools disinfected without chlorine whenever possible.


About the author

Amelia Bentrup is the owner and editor of a well-researched collection of natural home remedies. Discover natural cures for a variety of ailments and find specific information and safety guidelines for various herbs, vitamins, minerals and essential oils.

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