Story highlights

A CDC study found that nearly 80% of pools, other water venues had at least one violation

1 in 8 resulted in immediate closure because of the severity of the violation

Most common violations were improper pH levels, safety equipment issues, problems with disinfectant

CNN  — 

Nothing feels quite like jumping into cool water on a hot summer day – but before you do your best belly flop, the Centers for Disease Control and Prevention recommends that you check the last time that public swimming pool was inspected. You may be diving into a pool of public health violations.

According to a report published Thursday in the CDC’s Morbidity and Mortality Weekly Report, thousands of public pools, hot tubs and the like across the United States are closed each year due to serious violations of health and safety standards.

“No one should get sick or hurt when visiting a public pool, hot tub or water playground,” said Dr. Beth Bell, director of the CDC’s National Center for Emerging and Zoonotic Infectious Diseases. “That’s why public health and aquatics professionals work together to improve the operation and maintenance of these public places, so people will be healthy and safe when they swim.”

Eighty percent of public swimming pools, lazy rivers, hot tubs/spas and water playgrounds had at least one violation when inspected, based on more than 84,000 inspections of more than 48,000 places where people swim, lounge and play in chemically treated water in Texas, New York, Florida, Arizona and California. One in eight resulted in immediate closure of the venue because of the severity of the violation.

In what may not come as a surprise, kiddie pools and wading pools top the list. Of those, one in five had been closed at some point for one violation or another. The most common violations: improper pH levels, safety equipment issues and problems with the disinfectant concentration.

Chlorine and other disinfectants and chemicals are important to stop harmful pathogens in swimming pools and spas. A study published in April in the journal Environmental Science & Technology found that when those chemicals mix with “human inputs” – the stuff people add to the water when they get in, such as sweat, urine and cosmetics – they form compounds called disinfection byproducts. The researchers found there were more than 100 of these byproducts. Testing in the lab showed that exposure to these disinfection byproducts damaged cells. This means they may be linked to health problems such as asthma and bladder cancer.

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    The authors say disinfection byproducts can be minimized by frequently cleaning spas, more frequently exchanging water in pools and making sure people shower before they get in.

    The CDC doesn’t want you to stay out of swimming pools this summer. In fact, according to the agency, swimming is the fourth most popular sports activity in the United States and a good way to get regular aerobic physical activity. The CDC just recommends checking inspection reports before diving in to play.