There has been a recent push to switch to copper for hunting purposes to avoid lead poisoning, so there's that
It's a good way to market it and frighten the public to support the push, but frankly, it's scientific bunk. The lead has no poisoning risk to the hunter or those eating what they bring home. It's the fact that it makes the animals sick or deformed, as it accumulates in bones, organs and brains, which most people don't eat. The real reason for the push is to protect the ground water that the wildlife nests and rears in.
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That said, most lead poisoning occurs in a chronic sense. It's limited to the amount of sulfide it can react to in the short time it's in the stomach. The mass would stay intact for the most part and pass out the other end. That leads us back to the "chronic sense" statement. Lead littering a wildlife area would have ample time to react with natural sulfides and become a natural exposure issue to all the animals in the hunting area. Hence the real reason for the push. The need for sulfide is also why they can leave bullets inside people without them succumbing to lead poisoning. Sulfides also react with copper and make a pretty nasty poison, so pure copper also isn't used in ammunition, per above posted regulations. Ironically, it is the shots that missed which provide the hazard to the entire population and not the shots that took down an individual.
Lead in bullets is also an alloy of antimony, making it hard enough that chewing on it would be noticable and you'd have the oppertunity to spit it out.