Peeing in the swimming pool is not only absolutely disgusting it is also bad for your health.

According to new research, mixing your urine with the chlorine in the pool can create new substances that are very harmful to you. While some of it is caused by sweat about 90% is down to wee.

A new study published in the American Chemical Society’s journal Environmental Science & Technology looked at how chlorine reacts to sweat and urine and found that it creates trichloramine (NCI3) and cyanogens chloride (CNCI).

Both of these compounds are associated with lung problems but CNCI can also affect the heart and central nervous system.

While it is not clear why sweat and urine cause these substance, the study concludes that improved pool water is easily achievable from “improved hygiene habits on the part of swimmers.”

Health reasons or no health reason, peeing in the swimming pool is never, ever ok.