Lead Ammunition Research Articles

Lead‐based ammunition is a threat to the endangered New Zealand Kea (Nestor notabilis)

AbstractLead (Pb) poisoning is a significant threat to Aotearoa New Zealand's endangered kea (Nestor notabilis), an avian species important to Māori. Historically, exposure was thought to be from lead‐containing building materials; however, recent field observations suggest lead‐based ammunition as an additional source. We used stable lead isotopes to investigate the sources of lead to kea. Comparing 207 Pb/206 Pb ratios in kea blood (n = 91) to both ammunition and building materials, we found approximately one‐third of exposed kea (blood lead > 10 µg/dL) had lead isotope ratios consistent with exposure to lead‐based ammunition. As lead ammunition is still used, including in government‐sponsored culling programs, our data indicate an urgent need to shift toward non‐lead ammunition use to prevent further poisoning and aid conservation efforts. Collaborating with tangata whenua/Māori guardians, we advocate for immediate policy changes to eliminate lead‐based ammunition in kea habitat to safeguard this endangered culturally treasured species from extinction.

Lead exposure of a fossorial rodent varies with the use of ammunition across the landscape

Exposure to heavy metals has been documented in a wide range of wildlife species, but infrequently in ground squirrels. This is despite their tendency to be targets of recreational shooters and the accumulation of lead ammunition in the soil environments they inhabit. We analyzed lead and copper concentrations in liver (nPb = 116, nCu = 101) and femur (nPb = 116, nCu = 116) of Piute ground squirrels (Urocitellus mollis) and in soil (n = 75) on public lands in southwestern Idaho to understand how lead exposure may vary across a gradient of intensities and histories of shooting activity. The liver and femur of squirrels from areas used for recreational shooting for >30 years had elevated lead concentrations relative to areas where shooting was rare or did not occur (our negative control), but as expected, lower than areas used for military target training for >70 years (our positive control). Lead concentration in soils were higher in areas used for military target training than in those used for recreational shooting. There were no differences in copper concentrations in biological or soil samples among sites. These data suggest that ground squirrels can be influenced by the history of lead use in their local environment, and they illustrate another pathway by which human activity can influence toxicant exposure to wildlife.

Diving into the wicked discourse of lead ammunition for big game hunting

AbstractAs evidence regarding the toxicity of lead (Pb) amassed, the heavy metal became banned from several products, such as automotive gasoline and paint. However, Pb bullets are still used for hunting big game animals in most of the world. Although regulatory bans of Pb bullets may appear optimal solutions, stakeholders have reasons to oppose them, favor them, or lie somewhere in between. As the problem has transformed from biophysical to socioecological, we employed a wicked problem lens to dissect the discourse and help inspire targeted solutions. Herein, we identified and critically analyzed 4 relevant traits of a wicked problem: multiple stakeholders are involved, disagreement on a definition, unique nature, and being a symptom of a larger problem. To minimize the impact of these traits, our analysis suggests that voluntary Pb free ammunition programs are more likely to soothe conflict among stakeholders, enable collaborative action upon agreeing on common values, and promote programs tailored to the local landscape of sociopolitical power and values.

Lead poisoning of raptors: state of the science and cross-discipline mitigation options for a global problem.

Lead poisoning is an important global conservation problem for many species of wildlife, especially raptors. Despite the increasing number of individual studies and regional reviews of lead poisoning of raptors, it has been over a decade since this information has been compiled into a comprehensive global review. Here, we summarize the state of knowledge of lead poisoning of raptors, we review developments in manufacturing of non-lead ammunition, the use of which can reduce the most pervasive source of lead these birds encounter, and we compile data on voluntary and regulatory mitigation options and their associated sociological context. We support our literature review with case studies of mitigation actions, largely provided by the conservation practitioners who study or manage these efforts. Our review illustrates the growing awareness and understanding of lead exposure of raptors, and it shows that the science underpinning this understanding has expanded considerably in recent years. We also show that the political and social appetite for managing lead ammunition appears to vary substantially across administrative regions, countries, and continents. Improved understanding of the drivers of this variation could support more effective mitigation of lead exposure of wildlife. This review also shows that mitigation strategies are likely to be most effective when they are outcome driven, consider behavioural theory, local cultures, and environmental conditions, effectively monitor participation, compliance, and levels of raptor exposure, and support both environmental and human health.

Blood lead levels in an endangered vulture decline following changes in hunting activity

Lead ammunition stands out as one of the most pervasive pollutants affecting wildlife. Its impact on bird populations have spurred efforts for the phase-out of leaded gunshot in several countries, although with varying scopes and applications. Ongoing and future policy changes require data to assess the effectiveness of adopted measures, particularly in the current context of biodiversity loss. Here, we assessed the long-term changes in blood lead (Pb) levels of Egyptian vultures from the Canary Islands, Spain, which have been severely affected by Pb poisoning over the past two decades. During this period, the reduction in hunting pressure and changes in legislation regarding firearms usage for small game hunting likely contributed to a decrease in environmental Pb availability. As anticipated, our results show a reduction in Pb levels, especially after the ban on wild rabbit hunting with shotgun since 2010. This effect was stronger in the preadult fraction of the vulture population. However, we still observed elevated blood Pb levels above the background and clinical thresholds in 5.6% and 1.5% of individuals, respectively. Our results highlight the positive impact of reducing the availability of Pb from ammunition sources on individual health. Nonetheless, the continued use of Pb gunshot remains an important source of poisoning, even lethal, mainly affecting adult individuals. This poses a particular concern for long-lived birds, compounding by potential chronic effects associated with Pb bioaccumulation. Our findings align with recent studies indicating insufficient reductions in Pb levels among European birds of prey, attributed to limited policy changes and their uneven implementation. We anticipated further reductions in Pb levels among Egyptian vultures with expanded restrictions on hunting practices, including a blanket ban on Pb shot usage across all small game species.

Partitioning Human Dietary Exposure to Ammunition-Derived Lead in Meat from Game Animals Between Bullets and Shotgun Pellets

AbstractIn making recommendations for restricting uses of lead shotgun pellets and bullets for hunting, regulatory agencies, including those of EU and UK REACH, estimate human health risks from dietary exposure to lead from both ammunition types separately and attempt to monetise benefits of restriction options. However, available data from diet surveys are rarely sufficient to allow straightforward partitioning of dietary exposure between game killed with lead bullets and shotgun pellets. Because information on game meat consumption was limited, the UK REACH Agency’s draft socioeconomic analysis assigned all health-related economic benefits of lead ammunition restriction to shotgun pellets and none to bullets because a much higher tonnage of shotgun pellets than bullets is used. However, differences between the two ammunition types in exposure pathways make tonnage used an unreliable proxy for dietary exposure. Using primarily data for the UK, we partitioned exposure to lead by estimating tonnages of edible game meat shot with bullets and shotgun pellets separately and the mean lead concentrations in these meats. We estimated that ca.21% of human dietary exposure to ammunition-derived lead in the UK is from bullets and 79% from shotgun pellets. This new partitioning approach could be used to inform cost–benefit analysis in the UK and elsewhere when data from food consumption surveys are lacking.

Lead-free 22lr ammunition for sport shooting: A simple implementation or a huge challenge?

In Europe it is approximated that around six million people are active in sport shooting. Currently, most bullets are manufactured out of lead which in many cases is combined with a copper jacket. There are several reasons for using lead; lead is relatively cheap, soft, and has a high density, and is therefore often the ideal material for bullets. Currently, the EU is seeking a restriction or ban on the use of lead in firearm bullets, with the main motivation that hunting with lead bullets might result in lead poisoning of both animals and people. The proposed lead ban will also have a major impact on sport shooting, as it is likely to be subjected to the same regulations. One caliber that has been shown to be very difficult to produce as a lead-free alternative is 22lr (long rifle), which today is the most common caliber for sport shooting in many disciplines. Today, there are not many scientific investigations available which show the performance of lead versus lead-free ammunition in caliber 22lr, even though it would make sense to investigate the possibilities of designing lead-free ammunition before a possible lead ban is further discussed. In this work the performance of two common lead-free 22lr-cartridges is evaluated and shown in comparison with existing lead-based ammunition, with a primary focus on sport shooting. Performance has been evaluated under both summer and winter conditions to cover different sports shooting disciplines. The results of this study clearly show the difficulty of finding lead-free 22lr cartridges with acceptable performance on the market today. In fact, the performance of the tested lead-free ammunition is so poor that the EU’s proposed lead ban could completely ruin shooting as a sport due to a lack of functioning ammunition.

Outcomes from monitoring the fourth year of a five-year voluntary transition from hunting with lead to non-lead shotgun ammunition in Britain

The 2023/2024 shooting season was the fourth since UK shooting and rural organisations announced their intention that hunters should make a full voluntary transition from the use of lead to non-lead shotgun ammunition by 2025. The SHOT-SWITCH research project has monitored the proportions of wild-shot common pheasants Phasianus colchicus available to consumers in Great Britain that were killed using lead and non-lead shot in each of the shooting seasons since the beginning of the transition. In the study’s fourth season, 2023/2024, 93% of pheasants obtained during the usual sampling period had been killed using lead ammunition. Whilst this indicates a marginal decline in the proportion of pheasants shot using lead since the beginning of the transition, when it was over 99%, much remains to be done if the intended full voluntary transition to non-lead shotgun ammunition is to be achieved in its final season (2024/2025). Some food retailers intend to cease selling game meat products from animals killed using lead ammunition. Our study indicates that whilst all of a small sample of pheasant carcasses obtained from one of these retailers (Marks & Spencer) were from birds killed using non-lead shot, a larger sample obtained from another of the retailers (Waitrose) had mostly been killed using lead shot.

Wildlife rehabilitation records reveal impacts of anthropogenic activities on wildlife health

Wildlife faces many threats from anthropogenic activities and human-driven climate change. In this article, we use data from wildlife rehabilitation (rehab) centers, which admit and treat injured and sick wildlife, to understand the prevalence, patterns, and impacts of these threats and prioritize wildlife conservation efforts. Past studies have generally been more limited in geographic and taxonomic scope.We analyzed 674,320 digitized records from 94 wildlife rehab centers across the U.S. and Canada to learn about threats to over 1000 animal species. We identified key threats by examining conditions causing animals to be brought to centers.Overall, the largest proportion of wildlife injury and sickness were accounted for by human activities, including vehicle collisions, fishing-related incidents, and window or building collisions. Seasonal patterns in lead and pesticide exposure highlighted threats posed by hunting with lead ammunition and rodenticide use. We identified threats to iconic and threatened species such as bald eagles, brown pelicans, big brown bats, and common loons. We found that more animals arrived at rehab centers in the week after extreme weather events compared to the week before, for certain weather events in certain locations: e.g., hurricanes and floods in southern Florida. Across all species, wildlife rehabilitators were able to return about a third of treated animals back to the wild.These findings point to possible interventions to conserve wildlife populations and improve wildlife health, such as additional wildlife road crossings, improved regulations relating to fishing, hunting, and pesticide use, and incorporating wildlife into disaster management plans.

Effectiveness of an assurance scheme for wild‐shot game meat products in promoting a voluntary transition from the use of lead to non‐lead ammunition for hunting

Abstract A consensus has emerged in the United Kingdom that a transition away from the use of lead ammunition for hunting game animals would be desirable to reduce harm that lead causes to wildlife and the market for healthy game meat products. Voluntary methods to achieve this transition are preferred by hunters' organisations and the UK Government, though statutory regulation is also being considered. Voluntary transition methods include provision of advice to hunters by their non‐governmental organisations and moves by the game meat trade to switch to supplying only wild‐shot game products from animals killed using non‐lead ammunition. In this paper, I address the effectiveness of the practical implementation of a widely promoted wild‐shot game meat product assurance scheme by asking commercial stockists of game meat listed on the scheme's website about the demand for lead‐free game, their current labelling of products and the usefulness of the scheme's register of lead‐free shoots in helping them to source game shot using non‐lead ammunition. Responses were received from 39 stockists. Few respondents considered that there is currently significant demand for lead‐free game meat products, though more than one‐third thought that future growth in demand was probable. Few respondents currently sell products labelled as lead‐free. Only one respondent had found the register of lead‐free shoots useful and several were unaware of its existence. Based on this evidence and a review of progress with other voluntary initiatives, I conclude that substantial improvements in their effectiveness are needed if the benefits of a transition are to be achieved without statutory regulation.

Lead ammunition used by hunters has us all in its sights

Lead ammunition used by hunters has us all in its sights

Lead exposure of mainland Australia's top avian predator

Lead (Pb) toxicity, through ingestion of lead ammunition in carcasses, is a threat to scavenging birds worldwide, but has received little attention in Australia. We analyzed lead exposure in the wedge-tailed eagle (Aquila audax), the largest raptor species found in mainland Australia and a facultative scavenger. Eagle carcasses were collected opportunistically throughout south-eastern mainland Australia between 1996 and 2022. Lead concentrations were measured in bone samples from 62 animals via portable X-ray fluorescence (XRF). Lead was detected (concentration >1 ppm) in 84% (n = 52) of the bone samples. The mean lead concentration of birds in which lead was detected was 9.10 ppm (±SE 1.66). Bone lead concentrations were elevated (10–20 ppm) in 12.9% of samples, and severe (>20 ppm) in 4.8% of samples. These proportions are moderately higher than equivalent data for the same species from the island of Tasmania, and are comparable to data from threatened eagle species from other continents. Lead exposure at these levels is likely to have negative impacts on wedge-tailed eagles at the level of the individual and perhaps at a population level. Our results suggest that studies of lead exposure in other Australian avian scavenger species are warranted.

Risk communication and perceptions about lead ammunition and Inuit health in Nunavik, Canada

ABSTRACT Lead ammunition is commonly used to hunt waterfowl and other wildlife in the Arctic. Hunting with lead is problematic because the toxicant can be transferred to the consumer. Therefore, it is critical to evaluate perceptions and awareness of the risks associated with using lead ammunition among Arctic populations. Results of the Nunavik Child Development Study (a longitudinal health study gathering information on health and well-being among Inuit in Nunavik, Canada) included advice to eliminate the use of lead ammunition in hunting practices. We surveyed 112 Nunavik residents (93 women; 18 men) about their awareness of lead related messages, use of lead ammunition and risk perceptions about contaminants. Sixty-seven participants (59.8%) reported there was an active hunter in their household. We found that only 27% of participants had heard or seen the messages about reducing lead ammunition. After participants viewed the Nunavik Child Development Study messages about lead, 44% stated they would stop using lead ammunition. However, 28% indicated that they would continue using lead ammunition. We conclude that, while messages had an overall positive effect, further study is required to understand why people continue to use lead ammunition.

Efforts to ban lead ammunition: a comparison between Europe and the United States

AbstractThe human health impacts of lead have been known for millennia but the environmental impacts of lead ammunition have only received attention during the past 100 years. To a large extent the United States provided leadership in identifying and researching these effects and then spearheading campaigns to transition away from lead shotgun ammunition for waterfowl hunting. However, the appetite for further federal transition has largely stalled in the U.S. except for apparently limited action linked to individual states, charismatic species, and specific sites. Europe, on the other hand, though generally rather late to the table with regard to lead shotgun ammunition and waterfowl hunting, is now pushing ahead with several initiatives that are likely to see substantial partial, if not total, restrictions on the use of all lead ammunition (for shotguns and rifles) within 5 to 10 years. We discuss the policy drivers behind these moves, summarize the key attitudes and perceived constraints to transition, and provide (cautious) timetables and limited recommendations for future changes. Our discussion will include comparisons between efforts in the U.S. and those in Europe.

Association of Fish and Wildlife Agencies' perspectives on lead, alternative ammunition, and wildlife management

AbstractBetween 1970 and 2010, the Association of Fish and Wildlife Agencies (AFWA) approved 7 resolutions and one position statement related to lead, alternative ammunition, and wildlife management. The resolutions and statement address the following topics: transitioning from lead to nonlead shot for waterfowl hunting; addressing concerns relating to lead mobility at outdoor shooting ranges; and developing guiding principles for the future regulation of lead ammunition. We provide a brief overview of AFWA's committee structure and decision‐making processes, and also note the presence of ongoing discussions about lead ammunition in the AFWA Fish and Wildlife Health Committee and the AFWA Lead and Fish and Wildlife Health Working Group.

Special Section on Lead Ammunition

Special Section on Lead Ammunition

Support for nonlead shot for dove hunting in Illinois

AbstractMourning doves are the most hunted game species in the United States. Mourning dove populations are declining, and the continued use of lead shot has been cited as one contributory factor. We examined the relationship between support for a ban on lead shot when dove hunting and 3 sets of variables: (1) beliefs about lead and steel shot, (2) prior dove hunting experiences, and (3) hunter demographics. Data were obtained from a mailed survey of 4,330 dove hunters in Illinois (response rate = 59%). Our results indicated that 81% of respondents were opposed to restrictions on the use of lead shot and these individuals believed that lead ammunition did not pose a risk to wildlife and that steel shot was less effective than lead shot. Supporters of banning lead shot were almost twice as likely to use steel shot, reported 2 fewer years hunting doves, went dove hunting 75% as much, and harvested 2/3 as many doves as those who opposed a ban. Consistent with social‐psychological theory, beliefs were the best predictors of whether an individual supported or opposed a ban, followed by dove hunting experiences and demographic variables.

Towards an evidence‐informed strategy for communicating lead ammunition risks

AbstractLead hunting ammunition is a key source of lead exposure for wildlife and humans who eat wild game. To improve the effectiveness of lead ammunition risk communication, and avoid unintended negative effects from poorly conceived messages, we examined how New York State hunter education instructors view the lead issue. We conducted in‐depth interviews with instructors from 5 New York State regions from September 2020 to February 2021, which generated qualitative data on instructors' knowledge, beliefs, and opinions. We classified instructors into 3 groups: (i) concerned advocates, (ii) resistant skeptics, or (iii) ambivalent educators. Concerned advocates had substantial, accurate knowledge of the lead issue, as judged by the investigators, and a strong desire to avoid lead ammunition. Resistant skeptics believed lead ammunition risks are insignificant, exaggerated, or already well‐managed, and strongly resisted using nonlead alternatives. Ambivalent educators self‐reported limited knowledge of the lead issue or its significance and a general ambivalence, or even apathy, towards switching to nonlead alternatives. Across groups, instructors made clear they were (i) concerned about the higher price and lower availability of nonlead ammunition, (ii) uncertain about the relative performance of lead versus nonlead ammunition, and (iii) strongly opposed to legislation and regulation. Instructors also strongly believed that education and effective communication offer the best path forward, although most admitted rarely discussing the toxic effects of lead ammunition in class. We recommend that state hunter education program managers update their curricula and instructor training courses to include a module on the wildlife and human health lead ammunition issue. We also recommend that state and federal regulators cooperate strategically on communicating and managing lead ammunition risks to better address the issue and avoid unintended, unwanted outcomes.

Sources of exposure to lead in Arctic and subarctic regions: a scoping review

ABSTRACT Understanding lead exposure pathways is a priority because of its ubiquitous presence in the environment as well as the potential health risks. We aimed to identify potential lead sources and pathways of lead exposure, including long-range transport, and the magnitude of exposure in Arctic and subarctic communities. A scoping review strategy and screening approach was used to search literature from January 2000 to December 2020. A total of 228 academic and grey literature references were synthesised. The majority of these studies (54%) were from Canada. Indigenous people in Arctic and subarctic communities in Canada had higher levels of lead than the rest of Canada. The majority of studies in all Arctic countries reported at least some individuals above the level of concern. Lead levels were influenced by a number of factors including using lead ammunition to harvest traditional food and living in close proximity to mines. Lead levels in water, soil, and sediment were generally low. Literature showed the possibility of long-range transport via migratory birds. Household lead sources included lead-based paint, dust, or tap water. This literature review will help to inform management strategies for communities, researchers, and governments, with the aim of decreasing lead exposure in northern regions.

Lead concentrations in commercial dogfood containing pheasant in the UK

UK and EU regulators are evaluating the potential health benefits of restricting the use of lead ammunition. Little information is available on exposure of pets to ammunition-derived dietary lead from petfood containing meat from wild-shot game animals. We found dogfood including wild-shot pheasant meat to be widely available in the UK. 77% of samples from three raw pheasant dogfood products exceeded the EU maximum residue level (MRL) for lead in animal feed, with mean concentrations approximately 245, 135 and 49 times above the MRL. Concentrations > MRL were also found in a dried food containing pheasant, but not in a processed food, nor in chicken-based products. Lead concentrations in raw pheasant dogfood considerably exceeded those in pheasant meat sold for human consumption, possibly because the dogfood mincing process further fragmented lead particles from shot. Dogs frequently consuming such high-lead food risk adverse health effects; this should be considered within decision-making processes about regulation.