Steel is no good for a bullet. It needs to be softer than the rifling in the bore , so it can get the lands and grooves cut on it for the spin stabilization, and expand when it hits the target. Dangerous game bullets for Africa are solids, but copper/ brass alloy or some other hard alloy that will not expand.
I wonder if a hunter is allowed to shoot buckshot? Some states allow this, and I can see where 9 .32cal balls can get lost in a deers body cavity. I think outside of slugs, most quality bullets are a hard alloy and have good weight retention to reduce fragmentation. In 23 years hunting I have never come across lead in my food. Well, maybe 2x:D.
We went pheasant hunting, and those birds always hold a few BB's. But I have never seen lead in a deer except recovered muzzleloader bullets.
Whenever politics plays a role in game management, the hunters and the animals always lose.