Ryan told The Daily Telegraph, “They don’t work, they don’t work at all — they may be a bit better than a regular nappy, but they release fecal matter into the pool.”
Harmful contaminants, including giardia and Cryptosporidium, are introduced to pool water through feces. Cryptosporidium in particular can wreak havoc because it is resistant to chlorine and spreads quickly when people ingest water that is contaminated. In 2016, there were a number of Crypto outbreaks in the U.S., including one in Arizona that sickened 200+ people and one in Ohio that sickened nearly 1,000.
Ryan says swim diapers won’t prevent Crypto from being introduced to the pool.
“You could fit millions and millions of the parasite on the head of a pin so, no, they won’t stop Cryptosporidium oocysts entering the pool.”
In addition, Ryan says people don’t realize how much water they swallow when they swim. A study in 2006 showed that adults swallow about two tablespoons of pool water when swimming, and children swallow even more.
Public pools that want to better protect their swimmers should remind parents that they shouldn’t allow their children to swim if they’ve had diarrhea in the last two weeks. In addition, pools can install a secondary sanitizer that will effectively destroy Cryptosporidium when it is introduced to the pool.