Lead bullets are not a concern as far as contamination goes. They have little surface area compared to birdshot most are jacketed to boot. Most importantly, they aren’t ingested by wildlife.
As an aside, John Barsness is an avid hunter who’s eaten tons of game shot with lead bullets. His blood recently tested well within safe levels for lead...there is no risk in eating game killed with lead bullets.
Anyone who has a clue about diffusion processes could have told you that last. But clearly, this isn’t about science, this is about another way to hamstring gun ownership.