Upon research I discovered that dynamat is made w similar materials as peel and seal flashing. One should handle dynamat in the cautious manner that one would handle the poisonous flashing. Here's the msds for the Dynamat. http://www.rblproducts.com/msds/Dynamat.pdf Here's the msds for peel and seal http://www.mfmbp.com/doc/MSDS Sheet - Self-Adhering Products 04-01-14.pdf Both contain asphalt but neither have been found to be carcinogens, how every they don't recommend eating or setting it on fire and breathing them. Don't Sext and Drive.