Preserving agents are added into cosmetic products in order to prolong their expiry date. They suppress the increase of bacteria. Meanwhile they have a destructive influence on the cells of our organism. For example, broponol can release dangerous carcinogen nitrosamine which provokes emergence of cancer. All of us have heard about “E” supplements, some of which possess rather harmful properties. E-210, E- 211, E-212, E-213 and E-321 are toxic carcinogens irritating skin and mucous membranes. More information is available in special lists of dangerous preserving agents.