http://en.wikipedia.org/wiki/List_o...p_3_carcinogens

The agent (mixture or exposure circumstance) is not classifiable as to its carcinogenicity to humans. This category is used most commonly for agents, mixtures and exposure circumstances for which the evidence of carcinogenicity is inadequate in humans and inadequate or limited in experimental animals.

Permethrin

被歸類在第三類，那就是對人類沒有致癌性(?)