Agree that a lead bullet will kill you.
In terms of proof:
Lets agree that ingested lead is harmful. That is the general consensus of the medical professions, who etc.
A lead based bullet typically leaves 50% of its mass as fragments within the carcass and gralloch.
Then is it possible that lead fragments in venison and game are bioavailable???
Two studies in particular.
1) Hunt et al in 2009, published the following research where they fed pigs (breed and used for scientific purposes) with lead contaminated venison. Pigs are commonly used as a surrogate for man in scientific/ medical experiments. They showed that after eating lead contaminated venison there was significant rise in the blood levels of lead in the pigs. After a time blood lead levels will go down as the lead is then deposited in bone and bone marrow.
Human consumers of wildlife killed with lead ammunition may be exposed to health risks associated with lead ingestion. This hypothesis is based on published studies showing elevated blood lead concentrations in subsistence hunter populations, ...
pmc.ncbi.nlm.nih.gov
2) A further study in 2021 in Germany took the above work further. The pigs lead contaminated venison. The also marinated the meat in vinegar. This give rise to lead acetate, and they showed that marination of game meat increases of lead 5 to 6 fold. The article cites Spanish work on quail with shot pellets that yealded similar results.
Marination increases the bioavailability of lead in game meat shot with lead ammunition - PMC
Both of used X-Rays to determine lead in the meat.
Recent studies using electron microscopes have shown that lead bullets fragment in nano sized particles and these are widely transported around the animal carcass. Thesis is the particles are transported in the blood in the last moments of life. These nano particles cannot be detected by X-rays and are small enough, that when eaten they will pass through the gut wall directly into the blood.
Bullets, shot, and other projectiles from firearms can fragment inadvertently when they strike a target. The fragmentation process is concerning for hunting, where the projectiles are often lead-based, and the targets are animals that will likely be ingested by people and/or scavenging wildlife...
www.nature.com
There is now a large body of work showing that lead is a significant contributory factor to whole host of different diseases, from impairment of children’s growth and development, infertility, dementia and cancers, in particular blood cancers. The WHO’s position is that there is no safe level of lead in man. Certainly work on Leukaemia and Small Cell Lung cancer shows a very strong correlation between the diseases and lead in the blood at a nano gram level per litre of blood. Studies in patients with secondary AML where the lead is removed using chelation has shown a very high survival rate now three years after those studies were down. Normal survival rate after secondary acute myeloid leukaemia is a matter of days. This approach to treatment has no received orphan drug status (ie can be used in the terminally ill) and is going forward into clinical trials.