Over 9 Tons of Toxic Lead Discarded in Swedish Forests From Big Game Hunting

Over nine metric tons of toxic lead fragments have been left scattered across Swedish forests over the past 86 years from big game hunting gut piles, creating an ongoing environmental trap for vulnerable wildlife scavengers.

How Millions of Lead Bullet Fragments End Up in Swedish Forests

When hunters shoot big game such as moose, fallow deer, red deer, brown bears, and wild boars, traditional lead-core bullets expand and shatter violently upon impact. Each bullet typically sheds roughly 2.8 grams of metal, dispersing hundreds of millions of microscopic fragments into the surrounding animal tissue. While prime cuts of meat are harvested for human consumption, hunters routinely leave behind the visceral remains, known as gut piles, directly in nature during field dressing.

To quantify the scale of this hidden contamination, researchers evaluated harvest records from 1939 to 2024. Their findings were published in the Bulletin of Environmental Contamination and Toxicology, detailing an estimated 9,045 kilograms of lead deposited in forest ecosystems across Sweden during the 86-year study period.

Which Iconic Swedish Animals Face the Highest Exposure Risks?

Long-lived scavengers like golden eagles, white-tailed sea eagles, and Scandinavian brown bears regularly feed on these discarded gut piles. Because lead accumulates in bones and soft tissues over decades, repeated ingestion leads to chronic poisoning. Previous studies indicate that sublethal lead exposure severely impairs eagle flight performance and elevates mortality risks, while blood lead levels in Scandinavian brown bears significantly exceed safe developmental neurotoxicity thresholds.

The total volume of deposited lead translates to more than 450 million lethal doses for eagles alone. Lactating female bears are particularly vulnerable, as nursing transfers accumulated toxins directly into the blood and milk of dependent cubs. Furthermore, hunting dogs fed raw trimmings and bones from lead-shot game also face severe, occasionally fatal poisoning.

Why the Environmental Threat Continues to Grow Today

Rather than declining as a historical relic, the annual volume of lead-contaminated gut piles has reached record highs over the past decade. This surge is driven by a massive expansion in wild boar populations alongside robust harvests of other big game species. While non-toxic, lead-free alternatives matching the ballistics and efficiency of traditional ammunition are readily available on the market, the vast majority of big game hunters in Sweden have historically relied on lead-core bullets.

Countries like Denmark have instituted total bans on lead-based hunting ammunition, and similar restrictions are taking effect in parts of the United Kingdom and California. Researchers emphasize that given the record-high harvest numbers and the continuous influx of toxic heavy metals into natural food webs, transitioning completely to non-toxic ammunition remains the only sustainable solution to protect wildlife, hunting dogs, and human consumers alike.

The research was published in Bulletin of environmental contamination and toxicology on October 25, 2026.