Found this. Looks like Permethrin is actually non toxic to humans.
"Permethrin is an insecticide in the pyrethroid family. Pyrethroids are synthetic chemicals that act like natural extracts from the chrysanthemum flower. Permethrin is used in a number of ways to control insects. Products containing permethrin may be used in public health mosquito control programs. They may be used on food and feed crops, on ornamental lawns, on livestock and pets, in structures and buildings, and on clothing. Permethrin may also be used in places where food is handled, such as restaurants."
Looks like its whats used to treat fleas and lice on humans. Faiiirly safe as long as you dont stay in fumigated area for 3 hours afterwards.
Also, Less than 1% of the permethrin put on the skin of people was taken into the body. If permethrin is eaten, most of it is quickly absorbed. The pyrethroids easily pass through the lungs into the body if inhaled, but no specific data on permethrin was found.
http://npic.orst.edu/factsheets/PermGen.html