By measuring artificial sweeteners present in most people's urine, researchers reported that they can now tell roughly the amount of pee present in swimming pools.

Artificial Sweetener Acesulfame Potassium

In a new study, chemist Xing-Fang Li, from the University of Alberta, and colleagues were able to measure the amount of pee found in a pool by developing a test that measures the concentration of the artificial sweetener acesulfame potassium (ACE), which is present in processed food.

ACE makes a good proxy for urine in pool waters because it passes through the body unaltered and does not break down readily in pool waters.

By tracking the amount of ACE sweetener in swimming pools, the researchers found that one 220,000-gallon, commercial-size swimming pool tends to have nearly 20 gallons of urine, which would translate to about 2 gallons of pee in a residential pool.

The amount of urine the researchers found in pools is only about one-hundredth of a percent but the presence of pee in swimming pools poses health concerns.

Disinfection Byproducts

Although urine is sterile, it has compounds such as urea, ammonia, and creatinine that react with disinfectants to produce the so-called disinfection byproducts or DBPs and can cause eye and respiratory irritation. Long-term exposure to these chemicals has been associated with asthma in pool workers and even professional swimmers.

"Exposure to volatile DBPs, specifically trichloramine, in indoor swimming facilities can lead to eye and respiratory irritation(10-12) and has been linked to occupational asthma," the researchers wrote in their study.

Increased Cancer Risk

Nitrosamines, an example of DBP, is also known to cause cancer. While there is not enough evidence to attribute the nitrosamine levels in pools to increased cancer risk, a 2007 study in Spain found a higher incidence of bladder cancer in long-term swimmers.

Genotoxicity

Findings of another earlier study have also found an association between DBPs and genotoxicity, or DNA damage that can lead to cancer.

For the study, Manolis Kogevinas, from the Centre for Research in Environmental Epidemiology in Barcelona, and colleagues involved 49 adults in looking at the impact of DBPs. The researchers found that the participants had increased levels of biomarkers associated with cancer after swimming in an indoor chlorinated pool for 40 minutes.

"Our findings support potential genotoxic effects of exposure to DBPs from swimming pools. The positive health effects gained by swimming could be increased by reducing the potential health risks of pool water," Kogevinas and colleagues wrote in their 2010 study.

Red Eyes, Skin Irritations And Asthma Attacks

Most people think red eyes after swimming in the pool is caused by chlorine. The U.S. Centers for Disease Control and Prevention, though, blamed urine in swimming pool and not chlorine for having red eyes. Pool swimmers may also experience skin irritations as a reaction to byproducts of chlorine and human wastes, which include urine, body dirt, and sweat.

When chlorine comes in contact with human wastes, the resulting chloramine can get concentrated in the waters over time eventually moving up to the air and causing unwanted symptoms such as coughing and wheezing.