Fatalis - Most drums that contain food oil are lined. I am not sure why these would be unlined but if they are its a good deal.
You will not find any info on the bottom of the barrel that states the info your looking for. They are on labels that contain what it is with listed ingredients etc and what its hazards are for Safety and Hazards reasons along with MSDS. This might be where he is getting his info to you.
Seems crazy but they even have to be stored away from other items as well here in Ca. I work with this stuff everyday.
Where are you located in Ca?