I've co-authored some travel and other health publications for my industry (PM me if you want one), and its been interesting to see how the attitude on disinsection has changed over the years.
The chemical used in these sprays is a low dose of Permethrin, a pyrethroid common in household use. Permethrin is not bioaccumulative in mammals or birds (but it is in fish, perversely).
An often quoted paper giving the rationale for disinsection was:
http://www.winterthurhealthforum.ch/...sinfection.pdf
There have been a number of challenges to the orthodoxy but the prevailing attitude seems to have been that the use of Permethrin in aircraft disinsection was safe (to humans), however while Permethrin may not be bioaccumulative it seems that a small number of people may be instantaneously sensitive either to it or the surfactants/propellants in the mix:
http://www.cdph.ca.gov/programs/ohse...sinsection.pdf
would be intersting to cross-post to the medical forum. I expect its been aired (thats a pun) on pprune before.
Rob