whats the best/safest insulation for my cab??

[yote1234]

i have found lots of threads on insulating our cabs here, but nothing i've read has covered the very important subjects like.

******"health hazards"***** according to some MSDS data sheets most this stuff is bad in extreme heat conditions. and known to cause cancer and other health effects in labratory animals. (im glad im not a lab animal!)
http://www.cofair.com/pdf/msds/QRMat%20Safe%20Data.pdf


******"arizona extream heat" ****** the other important subject is dealing with 122 deg-up temps. i've read where as little as 100 deg temp can produce as much as 160 deg interior temp! also causing the "outgassing" effect. actually melting the product!.

so i would like to hear from all of you whom have knoweledge of a "safe" product.
whats the best? and the safest!?
is it ashfault or butyl product! or just ??