Water Is Life Blog

My Swimming Dilemma

Jul 3, 2013

I love swimswimmerming.  Pools, rivers, lakes, oceans.  I can’t think of a better way to cool off in the summer.  I can’t think of a better exercise.  And it is great for people of all ages. Nine years ago when I injured my back and suffered with sciatica, I started to swim regularly and it was and continues to be great therapy.  But I have a dilemma, the swimmers’ dilemma:


Being a strong  believer in using MULTIPURE Filters to remove chlorine from my drinking water, how can it be okay to swim in chlorinated water and swallow, inhale and absorb that chemical?  I started to wonder about why most pools continue to use chlorine and wonder what the medical research shows.

The first thing I did was to speak with Joe, the pool maintenance guru at the Recreation Center I swim at.  It’s a beautiful pool, incredibly clear and clean.  The temperature seems perfect to me and my eyes never burn.  Joe is 88 years old and when he became the swimming director in 1957  he also took responsibility for routine maintenance.  Fifty years of experience!  Over that period of times, some things have changed and others remain the same.  Here are some of the things he told me:

Chlorine was then and still is the most common and effective means of sanitizing a pool.  Its purpose is to keep the pool clear and kill off any bacteria.  In addition, most pools utilize some type of filtration system and constantly “turn over” the water.  In our pool, the water turns over five times a day and is filtered by a sand and gravel filter.  In the old days, Joe took measurements and added chlorine in the form of bleach as needed manually, but nowadays that is mostly automated.  As the water is pumped through the system, electronic probes test chlorine levels and PH and automatically call for the proper treatment.  Not too much, not too little…just right!

Chlorine can be gaseous, liquid or granules.  The gaseous chlorine can be more dangerous, since malfunctioning equipment or leaks can release the burning irritant into the nearby environment.  Did you know that in World War I, chlorine mustard gas was a very potent chemical used on the battlefield?

When the PH gets too high, chlorine is less effective.  And when the sun beats down on a pool, chlorine dissipates more quickly so has to be added more often.  Joe said that if you didn’t chlorinate, the water would quickly cloud up and you couldn’t see the bottom of the pool.

Lifeguards at our pool check the chlorine levels 6 times a day.  The Health Department inspects the operation twice a year, and most pool maintenance operators have taken a pool certification program.

Now here’s where it gets dicey:  Just like in drinking water, chlorine can combine with organic substances in the water and form more harmful and irritating compounds, disinfection byproducts like haloacetic acid (HAA’s).  In a swimming pool, those organics can come from sweat or urine or may be in the source water itself.  When those byproducts get too high, your eyes might burn or you might experience respiratory symptoms like allergies, sneezing, coughing or sore throat symptoms.

Further, there is some preliminary research that shows that regular swimmers have higher-than-normal levels of some of these chemicals in their bodies because they breathe the fumes and absorb some of them through their skin.  Although there are no proven links to cancer or heart disease, there is reason to be concerned since we know that chlorine byproducts can have those effects in drinking water.

There are alternatives, less toxic ways to sanitize pools.  Bromine, ozonation and saline treatment are some of these, but they are all less effective at removing bacteria and more expensive to use.

I continue to swim, figuring that the benefits outweigh the  possible risks but that risk analysis is for me an ongoing exercise.  Rather than swim everyday in the pool, I try to swim outdoors in the summer at Walden Pond, an unchlorinated natural location.  I vary my swimming with other non-aquatic aerobic exercise like running, biking and tennis.  I am glad my pool staff is doing its job well in monitoring and maintaining proper chlorine levels and am a little wary about less-monitored hotel swimming pools.

When you swim in a pool, shower first to remove sweat and other organics.  Shower immediately after swimming to rinse off the chlorine.  Try not to swim in a pool every day.  Learn about your particular pool’s chlorination by asking lifeguards or maintenance people.  And pay attention to any signs of eye, throat or skin irritation or newly developed allergies.