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.