I think it is highly dubious.
So the median concentration in wild venison is 0.01 mg/kg but the average is 0.195 mg/kg after excluding 3 high dosage instances from a total of 161 samples. Eh, how is that sample size appropriate to base a decision on, why remove only 3 carcasses from it. Just because they were high numbers ?
Other foreign data sources quote numbers based on not cutting out damaged meat. So they then charge on with some calculations based on 0.195.
The legal concentration limit is 0.1 mg/Kg. Even using this average an adult eating 120g of venison twice a week has an intake of 0.088 mg/Kg. So where is the problem there?
For a properly shot and butchered deer (I am making assumptions here) then the average should be nearer the median concentration of 0.01 mg/Kg so my intake would be 0.004 mg/Kg.
No problem !
Pheasant on the other hand would be about 0.704 mg/Kg so 7x the legal concentration limit if eaten twice a week.
One of the biggest challenges is not so much the cooking process but:
1) lead actually sitting in the meat - meat is acidic so any lead will leach a little bit into the meat. When frozen any activity will be minimised.
2) cooking may or may not add additional acid, but does raise the temp so speeds up any reactions. But the big challenge is stomach acids. Stomach acids - depending on species are pretty acidic, vultures a lot more so than man, but man is pretty similar to battery acid. A hearty meal of game will likely be a protein and fat rich meal thus will remain in the stomach and intestines for many hours. Some of the lead will be dissolved and adsorbed into the body. Once in body tissues, body cannot remove it. It may only a very few micro grams per meal - probably just enough to polish a lead pellet, but over time it builds up.
I have posted links elsewhere of work that has been done at the MD Cancer Clinic that shows a very clear link between elevated levels of lead in the blood and Leukaemia and Small cell lung cancer. The studies were only published last year, but the acerage level of lead in the cohort with leukaemia was 25nano mols per litre of blood, compared to zero in the healthy population.
The team is looking at ways to improve outcomes to leukaemia, in particular acute myeloid leukaemia. Studies show that by removing the lead, the disease is then treatable with very good long term outcome. Currently AML is pretty much a terminal condition.
Knowing the above, I personally am not going to put any lead into the human food chain.
As for Tungsten Matrix, it is recommended you only use 1/2 choke or less, and ideally in steel shot prooved guns. I am not convinced that combining tungsten powder with a plastic binding / matrix is a particularly good thing.
Ongoing developments of steel shot, especially steel shoot with high velocity loads works well. I have used the latest generation loads on the foreshore and ducks and geese fall down dead from a good range.
And the manufacturers are responding with steel shot loads suitable for most guns.
Yes they may not be suitable for tightly choked 100 year old game guns whose barrels are worn to min wall thickness.
And you might need the chokes reemed out on your AyA No 3 (choked 1/2 and full), but that is not beyond the realms of most gunsmiths for not a lot of money.
But for 90% of game shooting they work. And for the other 10%, well thats probably the job for a modern long barreled heavy over and under, or for your old Purdey or H&H, spend the same money on a new set of barrels suitable for steel shot - or use Bismuth - which will, at £1 plus a shot, make you pick your shots.
