Persistent Mercury Contamination in Shooting Range Soils: The Legacy from Former Primers

Area of Science:

• Environmental Science
• Soil Science
• Toxicology

Background:

• Mercury (Hg) compounds were historically used in ammunition primers.
• Limited data exists on mercury contamination in shooting range soils despite its toxicity.

Purpose of the Study:

• To assess mercury contamination levels in surface soils from Swiss shooting ranges.
• To evaluate the persistence of mercury in these environments.

Main Methods:

• Soil samples were collected from numerous shooting ranges across Switzerland.
• Mercury concentrations in surface soils were measured.

Main Results:

• High levels of mercury were detected in the surface soils of the investigated shooting ranges.
• Three ranges exceeded the Swiss guidance value for mercury in soil (500 µg kg⁻¹).
• Mercury contamination demonstrates high persistence in soils, with slow natural recovery.

Conclusions:

• Swiss shooting ranges exhibit significant mercury soil contamination.
• Mercury from historical ammunition use persists in soils, posing a long-term environmental concern.
• Natural remediation mechanisms for mercury in soils are slow.