Sorry, maybe I am being too obtuse.

Of course they would check further for your cause of death and maybe find out you died of a brain aneurysm then that would be your cause of death not lead poisoning, of course.

However if you were an eagle and had bad eyes (I am joking here) and ran into a tree and died of a brain aneurysm but they checked your blood and it had a high content of lead you would be counted (I am not joking now) in the study for lead poisoning from eating dead deer carcasses.

The statistic is convenient for the college professor who is doing a study paid for by the university or government or even an organization who champions animal rights.

So many guns, so little time!