Bear spray is exploding in the trash near Yellowstone National Park

Multiple bear spray cans have exploded in a transfer station near Yellowstone National Park, posing safety risks to sanitation workers and highlighting a growing disposal problem amid rising park visitation.

Workers at a garbage transfer station in Park County, Montana, have experienced frequent explosions of discarded bear spray cans during trash compaction, with the latest incident occurring in mid-April 2024. These explosions release high-pressure, flammable aerosol mist, causing safety hazards such as eye irritation and delays in work. The station serves communities around Yellowstone, where millions of visitors carry bear spray for safety in the park.

The problem has worsened over the past six years, paralleling the surge in Yellowstone’s visitors, which increased from 3.8 million in 2020 to an estimated 4.8 million in 2025, according to park data. Many visitors discard expired or unused bear spray cans in trash, as there are limited proper disposal options. Past recycling programs by manufacturers like Counter Assault and UDAP have ended, and currently, no dedicated recycling facilities exist in the area.

Local authorities are installing specialized collection containers for bear spray cans, but no facilities are yet available for safe disposal or recycling. Some rental companies now offer bear spray rentals to reduce waste, and efforts are underway to improve collection and disposal practices.

Why It Matters

This issue underscores the safety risks faced by sanitation workers handling trash contaminated with pressurized, flammable aerosols. It also highlights broader challenges in waste management for outdoor recreation areas experiencing increased visitation, raising concerns about environmental safety and the need for proper disposal infrastructure.

Background

Yellowstone National Park has seen a steady rise in visitors over recent years, leading to increased use of bear spray as a safety measure. While effective, the disposal of expired or unused cans has become problematic, especially since recycling programs have been discontinued or are limited in scope. The problem of discarded bear spray cans exploding in trash is not new but has gained attention with recent incidents, prompting local officials to seek solutions.

“We fairly frequently pop open a can of bear spray, which then spreads throughout the entire transfer station, forcing my guys to try to get out of the building as quickly as they can.”

— Matt Whitman, Park County Public Works Director

“There’s no end game for those cans. People carry bear spray for safety, but disposal options are limited.”

— Evan Stout, Yellowstone Wildlife Guide Company

What Remains Unclear

It is unclear how widespread the explosion problem is beyond the Yellowstone area, and whether new regulations or disposal programs will be implemented soon. The status of ongoing recycling initiatives remains uncertain, as does the future of manufacturer-led disposal programs.

What’s Next

Local authorities plan to install additional collection containers for bear spray cans and explore partnerships for safe disposal and recycling. Monitoring of explosion incidents will continue, and public education efforts may be expanded to encourage proper disposal practices.

Key Questions

Why do bear spray cans explode in trash?

Bear spray cans are pressurized aerosol containers that can explode if punctured or exposed to high heat, which can occur during trash compaction or if the cans are damaged in the waste stream.

What are the safety risks associated with these explosions?

Explosions can release flammable, irritating aerosol mist, causing eye and respiratory irritation for workers and potentially damaging equipment or facilities.

Are there safe disposal options for expired or unused bear spray?

Currently, there are limited disposal options in the Yellowstone area. Some rental companies offer returns, and local authorities are installing collection containers, but comprehensive recycling programs are lacking.

What is being done to prevent future explosions?

Authorities are installing specialized collection bins for bear spray cans and are exploring partnerships for safe disposal and recycling, aiming to reduce the number of cans ending up in trash.