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How Much Pee Is In Swimming Pools? You're In For A Rude Awakening

  • April 27, 2017

According to Today, a typical swimming pool contains about 8 gallons of urine. The idea of splashing about in a vat of chlorinated urine is repellent to most people, but this contamination shouldn’t be a surprise. One in 5 Americans admits to having peed in a pool, and a former U.S. Olympic team member said nearly 100 percent of competitive swimmers urinate in the pool. Hot tubs are also almost universally contaminated with urine.

Swimming in urine is unappealing, but is it dangerous? Many, including Olympic legend Michael Phelps, have argued it is not a hazard due to the chlorine levels. What he failed to consider is the smell that swimmers associate with chlorine is actually the smell of disinfection byproducts (DBPs). Rather than being rendered inert by chlorine, uric acid from human urine reacts with chlorine to form cyanogen chloride (CNCI) and trichloramine (NCI3).

The former, CNCI, is classified as a chemical warfare agent and is a known toxicant to your lungs, heart, and central nervous system. NCl3 is linked to lung damage. As for how dangerous this is, the researchers found that, in a worst-case scenario, urine in a pool might lead to about 30 parts per billion (ppb) of cyanogen chloride, which is well below the 70 ppb used as the maximum cyanogen concentration allowed in drinking water, according to the World Health Organization.

It is no surprise that the level of cyanogen chloride found in a swimming pool is not sufficient to incapacitate a swimmer or render them comatose. Convulsions and death only occur at much higher levels (about 2,500 ppb), an amount that would be difficult to generate in a typical swimming pool from urination alone. This doesn't mean that smaller doses are "safe," however, as DBPs have been linked to serious health problems at the levels found in swimming pools.

The risk of DBP exposure from swimming pools is real, but it doesn't necessarily mean you have to give up swimming. Swimming in an ocean is an excellent alternative, as is swimming in a lake or other natural body of water. You can also find a way to keep your pool clean from bacteria, algae and other organisms without the use of dangerous chemicals, such as choosing a saltwater pool.

One of the best solutions is NOT to chlorinate your pool and just use a maintenance "shock" treatment every five or six days, which will kill the algae buildup. The shock treatment volatilizes in about 24-48 hours and gives you a several-day window in which you can safely use your pool. 

You can also reduce the amount of organic material you bring into the pool, and thereby the amount of DBPs created. You should refrain from urinating in the pool, and demand that others, especially children, follow suit.   

Urine is not the only culprit. Any organic matter — including hair, skin, sweat and dirt —can react with chlorine to create DBPs. So if you use chlorine, it's going to be virtually impossible to avoid some exposure. This is why I recommend showering prior to entering a chlorinated pool. Keep in mind that DBPs exist in all chlorinated water, so you should install water filters that remove chlorine for both your shower/bath and your kitchen tap.