Quantitative assessment of environmental risk from lead pollution of shooting range soils

Abstract

Risk assessment indices such as risk assessment code (RAC), potential ecological risk index (PERI), geoaccumulation index (I geo ), contamination factor (CF) and enrichment factor (EF) provide a good measure of environmental risk posed by Pb accumulated in shooting range soils as opposed to total Pb concentration. For this reason, the S/P Pistol shooting range, even though accumulated lower concentration of Pb (685±218 mg/kg), exhibited 'very high risk' to the environment with RAC value of 77 exceeding the 51 set guideline value for 'very high risk' with a significant margin compared to MAT R2 (20888±5419 mg/kg) at RAC value of 48 and highest total Pb concentration. This implies that mobility and bioavailability of Pb at S/P Pistol shooting range will be higher posing a greater risk to biota even though contamination from Pb is low. Best shooting range management practices and low cost remedial actions such as phytoremediation and chemical immobilization should be carried out as soon as possible to minimize the bioavailability and mobility of Pb in the studied shooting ranges.

Ecological and Human Health Risks of Heavy Metals in Shooting Range Soils: A Meta Assessment from China

“…At two military shooting ranges in Korea, Eri value of Pb reached 3446, and 725, respectively [ 12 ]. In seven shooting ranges in Botswana, the Eri value of Pb ranged from 1192 to 56,272 [ 13 ]. Peddicord and LaKind [ 11 ] first evaluated the ecological risks of shooting rang contaminants for some animals, and found that Pb posed substantial risks to small mammals and grit-ingesting birds, but other contaminants, including As, Sb, Cu, Zn and PAHs posed minimal risks.…”

“…Particularly, Pb in shooting range soils can be highly bioavailable, indicating a potential toxicity and environmental risk [ 3 ]. However, only few studies assessed their environmental and health risks [ 10 , 11 , 12 , 13 ]. Although several studies investigated heavy metal contamination status of shooting ranges in China, to our knowledge, no studies have been conducted on their ecological and health risks.…”

Critical assessment of mechanistic pathways for chemical remediation techniques applied to Pb impacted soils at shooting ranges – A review

“…This was confirmed by the presence of primary Pb carbonates which were the predominant products found in soils, indicating that soil organic matter does play a vital role in Pb bullet and shot weathering and also controls Pb migration within the soil [69]. Besides soil properties and leaching tests, other measures such as risk assessment indices can be applied to determine the mobility, bioavailability and bio-accessibility of Pb at shooting ranges to the ecosystem; these have been detailed by whose research showed that all of the seven shooting ranges studied presented 'high risk' to 'very high risk' to the ecological system [70].…”

“…The iron sorbents immobilize Pb through its sorption by iron (III) hydroxides found in iron-based sorbents such as ferrihydrite, goethite and gibbsite [90]. Zerovalent iron (Fe°) will undergo weathering and corrode in the presence of oxygen and moisture leading to a variety of iron (hydr)oxides which provides new sorption and binding sites for Pb as shown in Equations (17)(18)(19) below [126].…”

“…In addition, few studies have tried to establish the speciation of Pb in shooting range soils in order to find out if Pb exists in the reactive chemical forms or in its inert chemical species. The speciation of Pb helps assess the mobility and bioavailability of Pb in shooting range soils, the degree of hazard posed and the best remediation strategies to undertake [19]. Shooting range soil remediation methods such as physical remediation procedures, chemical stabilization and phytoremediation have been applied in mitigating Pb pollution of shooting range soils.…”