Sentence:  As was the caveat about peeing in a pool. Of course, peeing in a pool wasn't dangerous to the person ... If you peed in a pool, and you were carrying the polio virus, presumably other people were put at risk, not the <WSD>peer</WSD> (pee-er?). 
Meaning of the word marked with <WSD> tags:  Someone who pees, someone who urinates.