Health

Deer Hunters at Risk

Lead bullets contaminate venison and can raise human blood lead levels

January 8, 2010

The powdery residue and jagged fragments of poisonous lead glowed on the dark X-ray film, like stars and scattered clouds in the night sky. As he studied one X-ray after another, Dr. Bill Cornatzer was shocked to see similar telltale markings on many of the film sheets.

A physician and hunter, Cornatzer wondered about the risks of eating deer shot with lead bullets, so he decided to X-ray 100 packages of venison meat that hunters had donated to a local food bank.

“I didn’t expect to find much lead,” said Cornatzer, a professor at the University of North Dakota Medical School in Grand Forks. “But when I saw the results I about fell off my chair. There was so much lead.” In all, 58 of the 100 packages contained visible amounts of lead — enough for Cornatzer to worry. He immediately phoned the North Dakota Department of Public Health to voice his concern.

In the two years since, Cornatzer’s findings have spurred an outcry in North Dakota and surrounding states. Deer hunting is to the Upper Midwest what sailing is to Cape Cod, or what skiing is to the Rocky Mountain West — it’s culturally ingrained. Many hunters pride themselves on donating venison to food banks. But after conducting tests that verified Cornatzer’s findings, state health officials in North Dakota, Minnesota, and Wisconsin pulled venison off the shelves of their food banks. Their concern was heightened by the recent completion of a large federal study which showed that consumers of hunted venison have 66 percent more lead in their bloodstream. Although none of these blood lead levels were high enough to be considered an imminent threat, many health experts are troubled.

“There are no safe levels of lead in humans and this was an additional source of lead we were not aware of,” said Shahed Iqbal, the lead researcher of the study conducted by the U.S. Center for Disease Control, which published the results in the September edition of the journal Environmental Research.

State health officials said they removed the donated venison from food banks to protect the health of embryos and small children. “For pregnant women and children there was concern,” said Dr. Stephen Pickard of the North Dakota Department of Public Health.

At high levels, lead is toxic to people of all ages. But because their brains are developing and gastrointestinal tracts absorb a higher percentage of the element, lead at any level poses a higher risk to children and developing fetuses and can cause lower IQ and cognitive function.

Iqbal’s federal study tested the blood lead levels of 736 citizens across six cities in North Dakota. Participants were also asked how often they hunt, how much venison they consume, and if there were other ways they could be exposed to lead.

Eighty percent of those tested had eaten wild venison, and their average blood lead level was 1.27 micrograms of lead per 10 deciliters of blood — two-thirds higher than people who did not consume wild game. The difference between venison eaters and non-eaters, Iqbal found, was large enough that it was very unlikely to be a statistical fluke.

The federal government considers children to have lead poisoning when their blood lead levels top 10 micrograms per deciliter. No participants in the North Dakota study had blood levels that high, although some came close — one elderly hunter’s level was 9.8 micrograms per deciliter. However, some states doubt whether the current definition of children’s lead poisoning is adequate. Cleveland, Ohio, just dropped its child lead poisoning threshold from ten to five micrograms per deciliter.

Most hunters were unaware that their venison may contain lead. “I figured the results were just because of sloppy processing,” said Lou Cornicelli, Big Game Coordinator for the Minnesota Department of Natural Resources. “So I ran 40 pounds of my own meat through [an X-ray machine]. Fifteen percent had lead in it. I felt like I was at an AA meeting. ‘Hi, I’m Lou and I had lead in my venison.’”

This shocked Cornicelli and led him to switch hunting ammunition, to reduce his family’s exposure to lead. “I switched bullets; I have a young kid,” he explained.

After firing, all bullets exit a rifle’s barrel and fly the same; how they behave upon impacting an animal is where they differ. Lead rapid expansion bullets, the most popular deer hunting bullets, are designed to transfer their energy into the animal by breaking into many small pieces at impact. “Conventional wisdom is to use a lead rapid expansion bullet; it’s been the standard bullet for 100 years,” said Cornicelli.

To cut down on lead in the deer he hunts, Cornicelli switched from a rapid expansion bullet to a controlled expansion bullet — one that peels back upon impact, but leaves no shards in the meat. Hunters can also use a copper bullet, which does not expand, but, like controlled expansion bullets, is more expensive than a lead rapid expansion bullet.

In a move to protect its citizens’ health, North Dakota now recommends that hunters not use lead rapid expansion bullets. California even banned the use of lead ammunition to protect the California condor — a bird whose population suffered in part because it fed on lead-riddled animal carcasses.

In addition to the Upper Midwest and California, other states are following suit by discouraging the use of lead bullets. Arizona has begun giving hunters discount coupons for lead-free bullets and Utah plans to implement a similar program. Internationally, 29 countries regulate lead ammunition. The Netherlands and Mauritania, for example, have outlawed lead ammunition altogether, while Canada has banned lead ammunition only for bird hunting.

Not everyone thinks the lead ammunition crackdown is justified. The National Shooting Sports Foundation, a trade association for the shooting, hunting, and firearms industry, believes the threat is overblown. Foundation officials have pointed out that no one in the study registered blood lead levels over the national standard.

Many hunters don’t buy the warnings either. “Most guys that buy lead bullets always refer back to their grandfathers, saying, ‘He hunted with pure lead bullets all his life and it didn’t kill him,’” said Blake Seibel, ammo specialist at Andrus Outdoors, an outdoor store in Dickinson, North Dakota.

Seibel added, however, that at least some hunters are paying attention. “The guys that are buying copper bullets are the ones that donate their venison,” he said.

That type of awareness is what Cornatzer was seeking when he first sounded the alarm two years ago. “I’m just trying to raise a red flag to sportsmen,” he said.

About the Author

Michael Glenn Easter

Michael Glenn Easter enjoys writing about the intersection between the environment, politics, and economics–he studied those three topics by creating his own major at Wheaton College. He is particularly interested in the environmental issues of the West and has spent summers interning for the mayor of Salt Lake City, a Utah-based environmental group, and the EPA’s Rocky Mountain Region office in Denver

Discussion

4 Comments

Knud Klit says:

Gentlemen,

Does fraqments of lead in any way harm humans?

Was blod levels ever checked?

If not, why?

Looking for your answer.

Knud Klit

Knud Klit says:

Thank you for the article. It does not fully convince me that a lead bullet is so dangerous that I would not use it. Of course I have always cut away any meat where I could see that fragments had hit.

The lead is in metallic form and that is why I was interested in if the lead contents in blood.

I am more afraid of eating ducks that have eaten lead pellets because this has been milled and absorbed in the meat.

Best regards

Knud Klit

Chris West says:

Thanks so much for getting this information out there. This is a very important issue that we are currently dealing with in Northern California where subsistence hunting, especially in native tribes, is very high. For additional information regarding lead ammuntion effects on wildlife and humans, one can access informational and primary literature on the Peregrine Funds website (http://www.peregrinefund.org/). In their pulication archive there are many studies with one by Hunt et al. likely being the most comprehensive in design and clearest in results (http://www.plosone.org/article/info:doi/10.1371/journal.pone.0005330).
Thanks again for your coverage of this topic.
Chris

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