They aren’t, but the most common ones are, excluding bromethalin and zinc phosphide. The biggest reason is safety, if accidentally ingested there are treatment options that can save a child or pet in that case. They also aren’t acutely toxic so they take enough time for treatment to be administered. Another reason is to try and reduce secondary toxicity if carcasses are eaten by birds because warfarin type poisons are less toxic to them than mammals.
Latest Answers