It also controls animal ectoparasites, biting flies, and cockroaches. It may cause a mite buildup by reducing mite predator populations. Permethrin caused mild irritation of both the intact and abraded skin of rabbits. It is not likely that reproductive effects will be seen in humans under normal circumstances. When permethrin is administered orally to rats, it is rapidly metabolized and almost completely eliminated from the body in a few days.
Aquatic ecosystems are particularly vulnerable to the impact of permethrin.
As a group, synthetic pyrethroids were toxic to all estuarine species tested. The bioconcentration factor for permethrin in bluefish is 715 times the concentrations in water and is 703 in catfish. This indicates that the compound has a low to moderate potential to accumulate in these organisms. Soil microorganisms play a large role in the degradation of permethrin in the soil. The addition of nutrients to soil may increase the degradation of permethrin.