LEAD BULLET: Tests by the CDC show that eating venison and other game can raise the amounts of lead in human bodies by 50 percent.
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To Dr. William Cornatzer, it was an unforgettable image, one that troubled him deeply.
An avid hunter, Cornatzer was listening to a presentation on the lead poisoning of California condors when an x-ray of a mule deer flashed on an overhead screen. The deer had been shot in the chest with a high-powered rifle. Cornatzer was shocked that the deer’s entire carcass was riddled with dozens of tiny lead-shot fragments.
“My first thought had nothing to do with California condors; it had to do with what I had been doing as a hunter myself, and what I had been feeding our kids,” said Cornatzer, a clinical professor of medicine at the University of North Dakota School of Medicine & Health Sciences.
“I knew good and well after seeing that image that I had been eating a lot of lead fragments over the years,” he said.
That realization led Cornatzer and a radiologist last year to X-ray 100 packages of venison that had been donated by a sportsmen group to a food bank. About 60 percent of the packages contained lead-shot fragments, even though it’s common practice among hunters to remove meat around the wound.
The discovery prompted North Dakota to warn pregnant women and children 6 and under not to eat venison killed with ammunition containing lead.
It also sparked a flurry of new research that raises questions about the safety of eating wild game, as well as a renewed debate about eliminating lead ammunition.
Earlier this year, the National Park Service announced a controversial plan to ban lead ammunition and fishing tackle in the parks, which Acting Director Dan Wenk said “will benefit humans, wildlife, and ecosystems inside and outside park boundaries.”
Cheap, durable and readily available, lead has been used in weapons and other products since the Romans first mined it more than 2,500 years ago. Bullets have contained lead, which upon impact mushrooms to create a larger wound, since the 14th century.
But lead is a dangerous neurotoxin, particularly for children and fetuses. Low levels can harm children’s developing brains, causing learning disabilities and reduced IQs. High levels can trigger severe neurological problems.
Sporting groups are opposed to any restrictions on lead-based ammunition, arguing that there’s no clear evidence that it is dangerous when used to hunt deer and other animals.
“The use of traditional ammunition does not pose a health risk to human beings,” said Ted Novin, director of public affairs for the National Shooting Sports Foundation, a trade association for the firearms, ammunition and hunting industries.
Novin added that “there has never been a documented case of lead poisoning among humans who have eaten game harvested with traditional ammunition.”
New research, however, has shown that eating venison and other game can substantially raise the amounts of lead in human bodies. The findings have prompted some experts to recommend bans on lead ammunition.
“We want to avoid having people exposed to lead to the extent that it’s feasible and practical, and it’s clear that one of the key ways to minimize exposure is to use alternatives to lead ammunition,” said Dr. Michael Kosnett, a medical toxicologist at the University of Colorado at Denver School of Medicine. “You’re putting food on the table to nourish your family. Why not nourish them with healthy food if that’s a possible alternative?”
The Centers for Disease Control and Prevention tested 736 people, mostly adults, in six North Dakota cities and found that those who ate wild game had 50 percent more lead in their blood than those who did not eat it. The lead exposure was highest among people who consumed not only venison, but also birds and other game, according to the study published last month in the journal Environmental Research.
Those who ate wild game meat had average lead levels of 1.27 micrograms per deciliter, compared with 0.84 for those who ate no game. Most said they either hunted the animals themselves or obtained the meat from friends or family members.
“What was most troubling is that as wild game consumption increases, the blood-lead levels increase,” said study co-author Mary Jean Brown, chief of the CDC’s lead poisoning prevention branch. “The strong recommendation we would make is that pregnant women should not consume this meat.”
The CDC is planning a second round of testing this year involving hunters in Wisconsin, Brown said.
The National Shooting Sports Foundation argues that everyone in the North Dakota study had blood-lead levels below the CDC’s health guideline of 10 micrograms per deciliter.
However, recent research has reported that children’s mental abilities are reduced by lead at levels far below the CDC guideline. Brown and others say there is no threshold below which lead does not cause harm, particularly with children.
As a result, the CDC recommends that “all nonessential uses of lead should be eliminated,” according to a 2005 statement. Less than 2 percent of children in the United States have lead levels that exceed the amount that the CDC considers safe. Most exposure comes from old, deteriorating lead-based paint, which was banned in 1978.
Another study, published in April, showed that eating venison containing lead-shot fragments can quickly raise blood-lead levels.
Researchers at Washington State University and Boise State University fed lead-tainted venison to four pigs and lead-free venison to a separate control group of pigs. The pigs that ate the venison containing lead fragments reached a lead level of 3.8 micrograms per deciliter after only two days—more than three times higher than the highest level in the control group of pigs, according to the study, which was sponsored by The Peregrine Fund, a group that advocates for the removal of lead shot to protect condors.
“At risk in the U.S. are some ten million hunters, their families, and low-income beneficiaries of venison donation,” the report says. One program, Sportsmen Against Hunger, donates the meat to low-income people.
The National Park Service posted the results of The Peregrine Fund study on its Web site, noting “that while the results are preliminary and much further study needs to be done to better assess risks to humans, it appears that if lead bullets are used, odds are high that you will ingest lead particles in ground meat.”
Mostly to protect wildlife, the park service plans to end the use of lead bullets and fishing gear in all parks. A public comment period will be held next year, said Jody Lyle, an agency spokeswoman.
“Our goal is to eliminate the use of lead ammunition and lead fishing tackle in parks by the end of 2010,” Wenk said when announcing the proposal in March. “We want to take a leadership role in removing lead from the environment.”
Although hunting is prohibited in most national parks, it is allowed on some park properties. Rangers also would have to stop using lead ammunition when culling herds or killing wounded or sick animals.
Hunting groups say any restriction on traditional ammunition will price many people out of hunting, because the alternatives--steel, copper or tungsten shells--can cost as much as six times more.
This is not the first time the federal government has considered restrictions on lead ammunition. The United States in 1991 phased out lead-shot for hunting waterfowl, mostly because bald eagles that prey on them were being poisoned.
Twenty-nine other countries have adopted voluntary or legislative restrictions. Some of the most aggressive regulations have been adopted in Europe, where lead-shot poisoning has killed white-tailed eagles and endangered Spanish Imperial eagles.
While there is no European Union standard for lead ammunition, Denmark was the first to ban lead shot for waterfowl in wetlands in 1985, followed throughout the 1990s by Norway, the Netherlands, Finland, England, Spain and Sweden. France did so in 2006. Denmark, followed by Norway and the Netherlands, extended the lead-shot ban to all hunted species in 2000.
California and Arizona also have taken action, implementing mandatory and voluntary bans, respectively, on lead bullets and shot in an effort to protect condors.
Pressure to ban lead-based ammunition in the U.S. intensified last year with the release of a report on threats to wildlife commissioned by The Wilderness Society and the American Fisheries Society.
The report said that lead fishing sinkers have poisoned brown pelicans, mute swans and Canada geese. Even more dangerous is lead shot in gut piles left behind by hunters and consumed by scavengers, including endangered condors, said Barnett Rattner, a wildlife toxicologist with the U.S. Geological Survey and a co-author of the review.
John H. Schulz, a resource scientist at the Missouri Department of Conservation, has calculated that as many as 15 million mourning doves are killed in North America each year from lead poisoning, mostly from eating spent lead shot that looks like the weed seed they depend on for food. That’s almost as many as the estimated 20 million mourning doves legally shot and killed each year by hunters.
But it’s the science pointing to possible human health impacts that has Schulz convinced that there’s more than enough scientific evidence to begin a phase-out of lead ammunition.
“Let’s not spend any more time studying whether the problem is significant. It is real. It is serious. It is significant,” Shulz said. “Now, how are we going to address it in a thoughtful and sensitive manner so no affected stakeholders are disenfranchised?”
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16 Comments
Add CommentThe primary reason lead shot was banned for waterfowl hunting was not because of the ingestion of lead in dead waterfowl by birds of prey, e.g. eagles, which would be a relatively rare occurence. Instead, lead shot, when used in waterfowl hunting, is widely dispersed in the environment on the bottom of marshes and other similar shallow waters and was commonly picked up by feeding ducks and geese with a consequent suprsingly high mortality rate
Reply | Report Abuse | Link to thisThe price issue with non lead projectiles is silly at best. The cost of actual hunting ammo would be minimal if "practice " ammo of the cheaper lead types were allowed to remain in production. Hunters would pay the additional cost for lead free ammo gladly to avoid the lead in their taken game. Hunters aren't stupid folk for the most part and they would understand the hunting non lead ammo use.
Reply | Report Abuse | Link to thisThe cost of actual hunting ammo would be very, very small for all hunters. We shoot very few rounds at game in the field annually. The vast majority of ammo is shoot in practice situations.
Developing projectiles without lead content would be easy and possibly superior to leads properties.
While no one wants to increase the amount of lead in our bodies or in the environment, I can't help wondering whocether these minuscule amounts of lead even matter when compared to the pollution (growth hormones, pesticides, dyes) in farm raised non-organic animals. Eating organic foods, primarily vegetation with occasional use of meat has served my family well for the last 30+ years.
Reply | Report Abuse | Link to thisThe State of Minnesota conducted research in this area last year. Results can be found at http://www.dnr.state.mn.us/hunting/lead/index.html
Reply | Report Abuse | Link to thisWhile the study is not intended to be exhaustive, the data collected is useful for hunters trying to decide what type of ammunition to hunt with.
Several questions to consider:
Reply | Report Abuse | Link to thisDo lower velocity bullets (30-30 type & muzzle loaders) release as much or any lead?
Does a particular type of bullet release less lead, copper jacketed hollow point, vs soft point, etc?
Lead birdshot in doves would be a much, much larger problem, any data on this??
Is the lead disbursed during the entry and fragmentation, or through blood circulation immediately afterward.
Does bonestrike by the bullet contribute to dispursment?
For years we borrowed from our children's futures by not having strong environmental laws so we could make stuff cheaply and have a higher standard of living after WWII. This is the same issue with lead shot. Throwing tons of shot onto our corn, maize, sorghum, or any seed field when hunting doves (or any other) is crazy at best. If we don't demand a change, people who don't understand our sport will do it for us. Lead is a great ammo for clays, but it needs to be kept out of our fields at least for bird shot. Copper jacketed bullets are designed to expand and this is the reason we have this issue, but I can't believe the amount of lead from big game is even close to the amount in birds, so the study above may have some flaws. All of this is ludicrous as the government allows millions of tons of mercury (far more toxic) into the atmosphere and therefore the oceans from coal burning plants.
Reply | Report Abuse | Link to thisThere are other sources of lead in the environment besides that originating from hunter's bullets. The article did not mention if wild game that had not been shot had been tested and the lead levels compared.
Reply | Report Abuse | Link to thisRegarding using lead only in practice ammo and not in that used to take the game, it would likely be difficult to match the bullet dimensions and weight between the two, obviously affecting ballistics. Consequently, you would have to practice a some with the bullets used for game so you can predict the bullets trajectory in the field.
The commenter above nailed the heart of the issue: the TONNAGE of mercury and other toxics emitted by coalburning power plants.
Reply | Report Abuse | Link to thisAs an avid hunter, I only shoot what I'm going to eat, which is often whitetail. I've always prided myself on the fact that I knew where my meat was coming from, hence fewer hormones, etc. than store-bought meat, so this article is concerning. BUT I am curious as to several points in this article, the first being terminology. Was the hunter using a rifle or a shotgun: "The deer had been shot in the chest with a high-powered rifle... the deers entire carcass was riddled with dozens of tiny lead-shot fragments." When using a rifle, you would use a single, solid projectile, not "lead shot," as you would with a shotgun and buckshot. I'd also like to echo 'Lownes' call for more information on bullet type, etc. What about shot placement, range, and caliber? I shoot in the head or heart/lungs without exception and with my .257 Roberts, I almost always have an exit. I think specificity is needed before scaring hunters and recipients of game meat from consuming it.
Reply | Report Abuse | Link to thisAs an avid hunter, I only shoot what I'm going to eat, which is often whitetail. I've always prided myself on the fact that I knew where my meat was coming from, hence fewer hormones, etc. than store-bought meat, so this article is concerning. BUT I am curious as to several points in this article. Was the hunter using a rifle or a shotgun? "The deer had been shot in the chest with a high-powered rifle... the deer’s entire carcass was riddled with dozens of tiny lead-shot fragments." When using a rifle, you would use a single, solid projectile, not "lead shot," as you would with a shotgun and buckshot. I'd also like to echo 'Lownes' call for more information on bullet type, etc. What about shot placement, range, and caliber? I shoot in the head or heart/lungs without exception and with my .257 Roberts, I almost always have an exit. I think specificity is needed before scaring hunters and recipients of game meat from consuming it.
Reply | Report Abuse | Link to thisFortunately, lead rifle bullets are increasingly being replaced by better performing alternatives, i.e. Barnes Solids, which are copper/zinc. These bullets appeared on the free market without a regulatory requirement, and have gained favor owing to their superior characteristics. Lead free bullets may or may not be designed to expand. Expansion is in general an over rated property; witness the acknowledged lethality of military ammunition which must not be made with expanding projectiles, per the Geneva Conventions.
Reply | Report Abuse | Link to thisShot is another matter. It has been illegal to waterfowl hunt with lead since 1991. Again, nontoxic shot such as bismuth, tungsten iron, etc have been introduced. Unlike the case of lead free bullets, the nontoxic shot was developed only after a regulatory incentive. Among the many varieties on the market today some enjoy substantially better ballistics than lead; others are poor substitutes. All the good substitutes are much more expensive than lead, but this is of no importance in the overall economics of an already expensive leisure activity.
Regarding paragraph two and the "lead-shot fragments" - this is just another example of a copy editor thinking that "shot" and "bullet" are equivalent words. You know, like "football" and "ping-pong ball" are. That said, even well designed expanding bullets often splinter extensively after striking bone, and those tiny chips can wind up a long way from the entry point.
Reply | Report Abuse | Link to thisTodays hysteria is: Eliminate lead bullets in the million to one chance that someone might end up with a slighlty elevated lead level. Is there any evidence that hunters and their families have evidence of lead poisioning? Maybe we should eliminate television because it causes a much higher rate of sedentary behaviour, which s a much higher health risk.
Reply | Report Abuse | Link to thisClaiming that mercury is worse problem than lead is a red herring and false dichotomy: both are bad and together they are worse than their sum. Toxins multiply their effects when used together, both heavy metals and other toxins like phthalates. It's not an either/or issue (we need to eliminate either mercury or lead), it's a both/and issue (we need to eliminate both mercury and lead), and they all need to be addressed now.
Reply | Report Abuse | Link to thisIf the house is flooding and filling with poison gas you don't waste time arguing about which is more dangerous, you do everything you can to deal with both and reducing either one is a good thing.
Sadly, calling this "hysteria" is a common reaction of people who don't understand (or are selfish and think they are somehow immune to) the persistent and systemic effects of these toxins. In our earlier flooding gassed house example, these people would be locking themselves in the upstairs bathroom and declaring that there's no problem because they have a shower and can open the window.
Is it really "hysterical" for someone to be alarmed that they are slowly being poisoned by the short-sightedness and arrogance of others?
You are right in pointing out the ambiguity in using the words "lead-shot fragments". I think what the author was trying to point out was that the fragments resulted from a lead-core bullet being "shot" with a rifle, not that a shot gun was used to shot "lead shot".
Reply | Report Abuse | Link to thisAt any rate, there is a lot of information out there that shows how much ALL centerfire, expanding lead-core bullets fragment when they hit an animal at more than twice the speed of sound.
In particular:
Do lower velocity bullets (30-30 type & muzzle loaders) release as much or any lead? Answer: The much lower velocities of muzzle loaders results in much less fragmentation.
Does a particular type of bullet release less lead, copper jacketed hollow point, vs soft point, etc?
Answer: Typical weight retention of lead-core bullets after being fired into ballistic gelatin varies from 70% to 90%, with soft point being the worst and bonded-core lead bullets being the best. That means that using a 150 grain (~10 grams) lead bullet will result in between 1 to 3 grams of highly powderized lead dust and fragments being dispursed throughout the wound channel. Some of the fragments travel as far as 18" away from the bullet's path.
The problem for any wildlife scavenger (or human for that matter) is when these lead fragments are inadvertently ingested with the rest of the meal. Taking the info from above, there is the potential for GRAMS of tiny lead pieces to be swallowed and pass into the very acidic digestive system, where the lead is leached from the fragments and passed into the bloodstream in short order (the lead must be exposed to acidic conditions to be leached). If the fragment is not passed quickly from the digestive system, the leaching process continues raising blood lead levels higher.
Here are some links that have more details:
http://www.peregrinefund.org/lead_conference/2008PbConf_Proceedings.htm
http://www.nps.gov/pinn/naturescience/condor_video.htm
http://www.azgfd.gov/w_c/california_condor_lead.shtml
Lead birdshot in doves would be a much, much larger problem, any data on this??
Answer: A little (see link of confernece proceedings above). Missouri is taking the charge on better understanding this lead pathway.
Is the lead disbursed during the entry and fragmentation, or through blood circulation immediately afterward.
Answer: See answer above
Does bonestrike by the bullet contribute to dispursment?
Answer: Yes, when a lead bullet hits bone, it will fragment much more than hitting just flesh. The weight retention figures above are just for
Does bonestrike by the bullet contribute to dispursment?
Reply | Report Abuse | Link to thisAnswer: Yes, when a lead bullet hits bone, it will fragment much more than hitting just flesh. The weight retention figures mentioned in the above reply are for bullets that hit ballistic gelatin, which is formulated to mimic soft tissue. If a lead-core bullet hits thick bone, the bullet often disintegrates much more into lead dust and fragments, with weight retention dropping to less than 50% of original values.