Triclosan

Triclosan was originally used in medical settings, but it has since seeped into the blood, urine, and breast milk of almost all of us, thanks to its inclusion in thousands of everyday items. The chemical is found in many antibacterial soaps, some toothpastes, and many personal-care products, but it’s also impregnated as a preservative in products that make germ-killing, deodorizing, “antimicrobial” claims. Those include countertops, toothbrushes, blankets, rugs, shoes, plastic toys, tents, brooms, garbage cans, undergarments, and a whole host of other items. When it finds its way into the environment, triclosan can wreak havoc: It triggers estrogen production that turns male frogs into females, and it’s toxic to algae and phytoplankton. When exposed to sunlight, triclosan can degrade into the cancer-causing chemical dioxin. And overuse of the chemical could result in microorganisms that are resistant to antibiotics.