Lead poisoning is caused by ingesting lead from hunting ammunition, affecting all wild birds. A recent study titled Plumbing in land birds in Spain: Contamination by lead ammunition beyond humid areas highlights the impact on biodiversity and potential risks to human health. The findings emphasize how lead in the environment—from bullets to fishing weights—can spread through soil, water, and food chains, harming wildlife and people alike.
Across Europe and Spain, regulators and advocacy groups have supported REACH registration, evaluation, authorization, and restriction measures that aim to limit lead use in natural settings. Lead remains banned for many uses outside the natural environment, including hunting ammunition and fishing weights, reflecting a growing consensus to curb exposure in the wild and at the table.
Current forecasts estimate that around 20,000 tonnes of lead are discharged annually in rural EU areas, underscoring a substantial environmental footprint. The study commissioned by SEO/BirdLife, with support from the Ministry of Ecological Transition and Demographic Challenges, involved experts from the Hunting Resources Research Institute and the Environmental Diagnostic and Research Institute. The primary takeaway is clear: lead from ammunition affects a wide range of wild birds.
Risk to humans
Lead ammunition fragments and pellets accumulate, especially in dense partridge hunting reserves and fixed shooting positions. This creates a risk of lead exposure for birds that ingest grain and for soils, water, and plants, potentially entering the broader food chain.
In Spain, studies found lead pellets in four granivorous bird species, with prevalence ranging from 3.9% to 9.3%. In three species—the red partridge, Moorish partridge, and wood pigeon—liver concentrations can be lethal for some individuals.
Lead is also a major cause of poisoning in birds of prey, linked to the use of pellets for small game and lead bullets for larger game.
Lead residues and elevated tissue levels were detected in 20 raptor species in Spain, with lethal levels observed in several individuals. The occurrence of lethal poisoning in species like griffon vulture, golden eagle, and goshawk exceeds 10% in some cases, with daily exposure in griffon vultures averaging around 3.2% to 3.3%.
Non-lethal effects observed in birds of prey exposed to high environmental lead include weakened enzyme function, altered phosphorus levels, compromised bone mineralization, and increased oxidative stress. In red partridges, adverse effects on clutch size, sperm quality, immune response, bone development, skin coloration, and antioxidant defenses have been noted.
Estimates suggest that ingestion of lead ammunition contributes to declines in raptor populations, sometimes dropping below the carrying capacity, with mortality in golden eagles reaching as high as 13.2% in certain contexts.
Ammunition also contributes to lead levels in game meats consumed by humans, with many game samples exceeding the EU limits for lead in meat.
Less toxic alternatives
The European Commission is expected to address restrictions on lead ammunition for all hunting and shooting activities in outdoor sports and on lead fishing weights. The European Chemicals Agency has already voiced concerns about lead’s environmental and health risks, but the EC has not yet published an initial formal proposal. A timely proposal is anticipated, with a three-month submission window from the EC.
Experts and conservation groups urge substituting lead with less toxic alternatives to sustain hunting and fishing traditions while protecting ecosystems. The 2018 recognition by ECHA of lead’s environmental and health risks reinforces this call.
Starting this week, Samarkand hosts the 14th Conference of the Parties to the Convention on Migratory Species, known as the Bonn Convention. The gathering will address lead elimination among other critical topics, even as earlier meetings reached broad agreement on this issue.
Lead, as a heavy metal, is highly toxic and bioaccumulative. Its effects become chronic, affecting uses once common in fuels, paints, water pipes, and other applications. Spain has been a pioneer in banning lead for hunting in wetlands, a move that inspired broader EU adoption and other countries. SEO/BirdLife notes that lead from hunting ammunition endangers not only waterfowl but also land birds, with a wide array of species reported to be affected.
For further reading, the study Plumbing in land birds in Spain: Contamination by lead ammunition beyond humid areas provides the detailed findings and context.