Photographed by Ellen von Unwerth, Vogue, November 1989
Swimming pools often carry the blame for green-tinged hair, but turns out there’s another culprit: your shower. “Every single day our water is so processed with minerals,” says celebrity colorist Tracey Cunningham, referring to the abundance of chlorine—in addition to bacteria, iron, rust, copper, and lead—that sometimes winds up in tap water. “My blonde clients will come in after six to eight weeks with dull hair. That’s because of mineral buildup. It’s the bane of my existence.” To preserve color—and prevent lackluster, “limey” lengths—Cunningham now recommends her clients (including Kim Kardashian West and Emma Stone) use a filter.