Pool Water Contains More Poop Than You'd Think

A group of researchers from the CDC sampled water from 161 public and private pools and water parks in Atlanta and found that half of them were contaminated with e. coli, which comes from -you guessed it- poop.

The study, published in the latest Morbidity and Mortality Weekly Report, specifically looked at pools in Atlanta, but the researchers say such contamination is likely a widespread problem in U.S. pools, thanks to swimmers not washing themselves off before taking a dip. According to the scientists, each of us carries about 0.14 grams of fecal material into the pool — and that doesn’t include accidents or cases of diarrhea. Among municipal pools, the genetic testing for pathogens detected E. coli in 70% of the filters, while 66% of the water parks contained the bacteria and 49% of pools in private clubs showed evidence of the contamination.

“These findings indicate the need for swimmers to help prevent introduction of pathogens, e.g., taking a pre-swim shower and not swimming when ill with diarrhea, [for] aquatics staff to maintain disinfectant level and pH according to public health standards to inactivate pathogens, and state and local environmental health specialists to enforce such standards,” the authors write in their report.

Because of the way they did the tests, the researchers did not determine whether the bacteria was alive. If pools are properly chlorinated, they should be dead. Atlanta had no reported pool-borne illnesses last summer, when the samples were taken. But just to be sure, try not to swallow pool water. More