Speciation Distribution of Heavy Metals in Dutsen-Soyaya Shooting Range soil within the Nigerian Army Base Camp, Kachia, Kaduna State, Nigeria

In soil, heavy metals can be found in large quantities. Anthropogenic activities raise heavy metal concentrations in the soil, which are readily assimilated by food crops. Military training exercises such as shooting in a shooting range with bullets containing a mixture of heavy metals raise the concentration above the baseline over time, affecting military personnel and crops alike negatively. It is critical to determine the effect of shooting via military artillery operations on the soil heavy metal concentrations, mobility, and bioavailability on the shooting range by analyzing soil samples collected from selected areas of the shooting location. The speciation of heavy metals (Copper (Cu), Manganese (Mn), Nickel (Ni), Lead (Pb), Arsenic (As), Chromium (Cr), Cobalt (Co) and Zinc (Zn)) distributed in the Dutsen-Soyaya Shooting range soil within the Nigeria Army Base Camp, Kachia, Kaduna State, Nigeria was investigated. The concentration of these metals after undergoing sequential extraction procedures was analysed using Atomic Absorption Spectrophotometry. The distribution fractions of these metals in the shooting range soil were as follows: Co: Residual > Organic > Fe – Mn Oxide > Bound to carbonate > Exchangeable. As: Fe – Mn Oxide > Residual > Organic > Bound to carbonate > Exchangeable. Cr: Exchangeable > Fe – Mn Oxide > Bound to carbonate > Organic > Residual. Ni: Fe – Mn Oxide > Exchangeable > Bound to carbonate > Residual > Organic. Mn: Residual > Fe – Mn Oxide > Bound to carbonate > Organic > Exchangeable. Pb: Residual > Organic > Fe – Mn Oxide > Exchangeable > Bound to carbonate. Zn: Fe – Mn Oxide > Bound to carbonate > Residual > Organic > Exchangeable. Cu: Residual > Bound to carbonate > Fe – Mn Oxide > Exchangeable > Organic. Although the total concentration of some of these metals (Co, As, Cr, Mn, Pb and Ni) were above the permissible limits by WHO standards, the toxic metals speciation showed that they were mostly predominantly concentrated in the non-bioavailable fractions of the shooting site soils.