The poison commonly detected in exhumed bodies is:

The greatest concentration ofarsenicis found inhair and nails. Its deposition in hair may begin in 15 days after administration. Arsenic becomes fixed in thecancellous tissue of bones, chiefly thelong bones, owing to the conversion of their phosphates into arsenates. Its presence can be detected in the bones for prolonged periods. Hence, it is prudent to preserve long bones for chemical analysis in suspected cases of chronic arsenical poisoning when a body is exhumed.