:slfg: That's just the flash name for permethrin, which is the active ingredient in No Spiders and most insecticides. It's bad for fish and cats, so be careful when spraying...
It's generally consider harmless, but there's some interesting stuff on Wikipedia, which makes me want to use it as little as possible, i.e not at all :
Permethrin does not present any notable genotoxicity or immunotoxicity in humans and farm animals, but is classified by the United States Environmental Protection Agency (EPA) as a likely human carcinogen, based on reproducible studies in which mice fed permethrin developed liver and lung tumors.[10] Carcinogenic action in nasal mucosal cells due to inhalation exposure is suspected, due to observed genotoxicity in human tissue samples, and in rat livers the evidence of increased pre-neoplastic lesions raises concern over oral exposure.