Like many people who swim in the summer, you might have assumed it's the chlorine that makes your eyes so red in pools.

That's not exactly true, the Centers for Disease Control says in its annual healthy swimming report. It turns out the cause is actually urine binding with chlorine to turn into something called a chloramine. In addition to being an eye irritatant, chloramine, a derivative of ammonia, has been linked to respiratory problems among some swimmers.

ncG1vNJzZmivp6x7uK3SoaCnn6Sku7G70q1lnKedZLumw9Joq6hlqaTCs3nHnpilrJhkxLF7kWlobmdga3xzgY6smqKdnqm2tMDSZpueq5OntqOxjK2fnmWXp7y0v4yrnJqrn6N6uLTYZrCoraJisrqx0maqqKWVqbausdJmqq2hnpx6tcHRp2SrnZRitq950rCgpqWZo7RuvM6oo6xn