Energetic compounds and heavy metals in surface soil of training ranges on southeast coast of China: pollution characteristics and source analysis.

To assess the environmental impact of training activities, surface soil was systematically collected at 3 training ranges (designated as A, B1, B2) located along the southeast coast of Guangdong, China. Analytical results of energetic compounds (ECs) in soil revealed that 2,4,6-trinitrotoluene (TNT) was the predominant ECs, with a mean concentration of 234 ng/g. The detection rate for Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was over 50%, peaking at 710 ng/g. Heavy metal analysis demonstrated significant enrichment of cadmium (Cd), mercury (Hg), lead (Pb), copper (Cu), and arsenic (As) in soil. Particularly noteworthy were the Cu and Pb concentrations in range B2, reaching maximum levels of 259 mg/kg and 801 mg/kg, respectively. Metal enrichment was predominantly attributed to metallic components and shrapnel fragments originating from explosive materials. Field investigations indicated that metallic fragments dispersed in surface soils exhibited limited weathering, with iron (Fe) constituting the primary metallic element, accompanied by trace amounts of chromium (Cr). The quantitative analysis of ECs and heavy metals concentrations suggests a clear trend of environmental accumulation. These findings underscore the necessity for implementing long-term environmental monitoring programs and conducting comprehensive risk assessments to evaluate potential ecological risks related to military training activities.