Phytoremediation of soils affected by shooting practises: lessons learned, challenges and future opportunities

Abstract

Metal(oid)-contamination of soils within or near recreational shooting ranges is an environmental problem that has worsened in recent decades. The constant fall of ammunition (composed mainly of lead -Pb-) into soils and its dispersal has resulted in areas with high total Pb concentrations, ranging from thousands to tens of thousands of mg kg^-1 dry weight of soil as one approaches the firing line or berms. Once deposited in the soil, ammunition fragments are highly susceptible to weathering processes, which release Pb in its more mobile and potentially toxic chemical forms. Phytoremediation has gained momentum in recent years as an alternative to physico-chemical treatments for the control and management of Pb contamination in shooting ranges, due to it is environmentally friendly, easy to applicate and low cost. In this context, the main objective of this work is to review the state of the art of phytoremediation of soils affected by shooting practices and, in addition, to reflect on the current and future challenges to be addressed for their optimal remediation.