Lanolin

Causes allergic skin rashes. Cosmetic-grade lanolin can be contaminated with pesticides, including DDT, dieldrin, and lindane, which are carcinogenic, and diazinon, which is neurotoxic. Can enter the bloodstream through the skin. Labels do not disclose which lanolin-based ingredients are pure. Found in a wide range of cosmetics, hair products, ointments, and lotions.