If you’re a blonde swimmer you might’ve noticed that, eventually, the water turns your tresses a lovely shade of chartreuse. Here’s a little-known fact: it’s actually not a result of chlorine. The culprit? The oxidized metals found in the solutions used to cleanse pools (like copper, which turns from brown to green over time – i.e., the Statue of Liberty). These metals can deposit a greenish hue onto strands, which shows up on light hair. Good thing it’s easy to reverse! Simply remove the shade with a detoxifying, clarifying shampoo.