Fun fact, tap water that you drink, and the water you bathe and shower in also have it in it. It's not as "safe" as people like to believe. When you heat it up, even in shower and baths, that means it's going into the air and you're breathing it in as a gas. That's why some people with sensitivities (skin, lungs, or other internal works) get filters that filter it out, and are sure to get special ones that do that for bath and shower taps too. I'm just really grateful that I can deal with it, and therefore can handle pools! It's still not good for you though :/ I've heard that people can develop asthma from swimming in pools too often (like competition swimmers)