he may have not been drug free, but as you can see he is smooth around the waist and retaining some water, so the diuretic abuse that fried his kidneys plus any other hard androgenic and toxic compounds were probably not consumed...
the thing I dont understand though is why he competed after having learned that his kidneys were fucked...
Well I guess its pretty obvious since most people who get to this size are mind fucked as well even if they dont admit it and try to prove otherwise