Mother's milk contains carcinogenic toxins. But health authorities still advocate breast feeding as the benefits far outweigh the risks. According to a report of the Committee on Toxicity of Chemicals in Food and Consumer Products and the Environment, UK, British infants are consuming large quantities of polychlorinated biphenyls (PCBs) and dioxins through mothers' milk. In some cases, the levels of PCBs are high enough to cause cancer. PCBs are chlorinated hydrocarbons which were widely used in industries and accumulate in body fat ( The Lancet , Vol 349, No 9064).