Think washing your hair is a harmless act of hygiene? Think again! That is, if researchers into the dark sides of shampoo have anything to say about it. It turns out that a fragrance used in many shampoos is a common allergen that may even cause eczema. Air-oxidized linalool, which is present in up to 80 percent of shampoo products, has been ranked as the third most common eczema-causing substance, falling behind only nickel and cobalt. And even if you escape the eczema, once you wash and send those suds down the drain, they start spreading drug-resistant bacteria, according to new reports. Sewage sludge collected by municipalities contains antibiotic-resistant microbes that grow faster in the presence of chemicals in shampoo and household detergents. Bad news for clean freaks—but hey, the no-shampooing look has certainly worked for some.
Image: Flickr / joeltelling