Abstract:
Shooting ranges are commonly contaminated with Antimony (Sb), which is released during
weathering of bullets. Antimony in lead bullets is a serious environmental concern in shooting range soils and consequently its concentration must be measured in shooting ranges for this study.Thebephatshwa shooting range (TAB) in Botswana was used to determine Sb concentrations. The Sb concentrations were determined using ICP-OES and in all the sampling sites of the shooting range being investigated. Soil samples recorded at TAB shooting range berm showed variable total concentrations of antimony in the range 38±1 to 283±12 mg/kg. Total antimony concentrations found in the soils were higher than the set regulatory levels of 36mg/kg by the World Health Organization and the United States Protection Agency 31 mg/kg. The upper berm recorded elevated levels of antimony 283±12 mg/kg due in part to the highest density of spent projectiles found in this part of the berm. Sequential extraction studies established that antimony was partitioned mostly in the organic and residual fractions of the soil. Environmental pollution risk assessment based on geoaccumulation index (Igeo), contamination factor (CF) and enrichment factor (EF) of Sb indicated that all the four sections of the berm posed high risk to the environment. The upper berm exhibited extreme pollution from antimony of Igeo~9, very high contamination of CF~744 and extreme antimony enrichment EF~506 than the other three sections studied when compared to the set Igeo . Elevated levels of antimony at TAB shooting range call for best shooting range management practices, soil remediation and reclamation methods to be carried out at this shooting range to minimize the mobility and bioavailability of antimony.
