It’s hunting season and that means it’s also time for the pseudo-science cautionary news articles claiming traditional ammunition is a health threat. Don’t believe them.
A recent piece in the Bulletin of Environmental Contamination and Toxicology describes an analysis of metal fragments in game meat. This weak research report is clearly part of an ongoing effort to reject the CDC’s blood lead level thresholds and assert that there is no non-dangerous level for humans.
Despite hundreds of years of evidence that it is safe to consume game meat taken with traditional ammunition that contains lead components, anti-hunting groups argue that the potential for metal fragments to remain in game meat poses a threat to humans.
The analysis published in the Bulletin is thin at best. The authors used a very small sample of only 10 deer. And, while the research assumes that “the number of deer being sampled was equal to the number of deer submitted by the hunters for processing,” there is no evidence to support this extrapolation.
A Centers for Disease Control (CDC) study of blood lead levels in North Dakota hunters validates what hunters have always known: consuming game harvested with traditional ammunition containing lead does not pose a human health risk.
- The average lead level of the hunters tested was actually lower than the blood lead level of the average American, including non-hunters.
- The average lead level of children in the study was only .88 micrograms per deciliter of blood; the CDC’s level of concern for lead in children is 10 — more than 10 times the amount found!
- The difference between participants who ate wild game harvested with traditional ammunition and non-hunters was only .3 micrograms — a clinically insignificant number.
The study involved radiograph imaging of their game samples to find “potential metal fragments” based purely on appearance. This technique is fraught with error, as the imaging cannot reveal what the potential fragments actually are. Rather than metal, they may have been bone fragments. The notion that tiny pieces of lead can disperse widely through dense flesh is dubious at best.
Even with the small sample, and the flawed use of imaging, the results show that most of the packets did not contain suspected fragments. According to the report, “Thirteen of the 27 ground venison packets (48%) from shotgun-harvested deer contained at least one metal fragment…In packets from shotgun-killed deer that contained metal fragments, the number of fragments ranged from 1 to 3,” again not showing a vast disbursement of fragments.
Further eroding the methodology, the authors note that, “Due to budgetary limitations, not all suspected particles could be analyzed. Seven suspected metal fragments from six packets were chosen for chemical analysis because they originated from a single deer via a single commercial processor.” This means that out of the 10 deer the samples came from, only samples for one single deer from one processor was tested to see whether it was lead.
When this small sample was tested, the report found, “The elements copper, manganese and lead were below detection in 93.9%, 10.2% and 79.6% of the analytical subsamples, respectively. At least one subsample from each sample had a detectable quantity of lead.” These underwhelming results are far from a persuasive argument against the use of traditional ammunition.
The authors seem to agree, stating that “An average serving selected randomly from any one of our packets (shotgun-harvested, commercial processor) would be predicted to have lead concentrations within the range from BD to 8.42 μg g−1, or a dose from~0.00 to 4.4 mg of lead in one serving.” Despite the small, cherry-picked sample from a single deer and processor, the analysis still found that a serving of meat from that deer could have a dose of 0.00 mg of lead.
In the authors’ discussion of other literature on this topic, they note that there are studies that have found even less lead exposure from game meat. The authors argue against averaging lead concentrations across an entire animal, as other researchers have done, although that “may be a statistically more rigorous measurement of lead concentrations…” They argue that their less rigorous measurements better estimate the actual ingesting of one or more fragments.
It is easy to dismiss such thin research in an academic setting. But unfortunately, the study made it into the news, further promoting the flawed results. In the news article, the authors equivocate metallic lead shot with other sources of lead such as paint chips, without any mention of the fact that metallic lead is not as easily absorbed by the body.
At the very least, the researcher quoted acknowledges that he does not know how much of these fragments would actually be absorbed by adults. Although, he inexplicably leaps to an argument that children would “take up about half the lead they ingest into their body” with no research cited in the article or in the study itself for that assertion.
NSSF encourages the media and hunters to carefully read studies that attempt to disparage the consumption of game taken with traditional ammunition. For more information about valid research on this topic, see a review online here.
Hunters, while evaluating studies, should also follow sound field dressing practices, including trimming around the would channel, to reduce potential exposure.
Elizabeth McGuigan is Director of Legislative and Policy Research at the National Shooting Sports Foundation.