Nothing says summer like the smell of chlorine from a pool . . . but it’s not chlorine you’re smelling. It’s chloramine, a chemical produced by the reaction between chlorine and urine. And it’s what makes your eyes red. When people think it’s okay to stay in the pool for bathroom breaks, pools become a massive, festering slush of disease, with everything from asthma and lung infections to Legionnaires’ disease associated with swimming in dirty pools.