Kids who regularly swim in pools may be at risk for developing hay fever as adults. A study from the GSF-National Research Center for Environment and Health in Neuherberg, Germany, reveals that adults who reported swimming in a chlorinated pool at least three to 11 times each year at school age were more likely to develop hay fever than those with no exposure to chlorinated pools during those years. Researchers think chlorine exposure may damage the lining of the lungs, which could make lungs more susceptible to allergens. "Babies and young children are more vulnerable to toxins because their lungs and immune systems have not yet matured," says lead study researcher Yvonne Sch