Soil Quality Assessment in Pomegranate Orchards of Solapur: A Study of Heavy Metal Risks

Abstract This study investigated the levels of specific heavy metals—Iron (Fe), Manganese (Mn), Copper (Cu), Zinc (Zn), Chromium (Cr), Cadmium (Cd), Lead (Pb), and Nickel (Ni)—in soils cultivated with pomegranate across five prominent tehsils in Solapur district. The soil samples were examined using Atomic Absorption Spectrophotometry (AAS). Results indicated that the concentrations of certain heavy metals surpassed the maximum allowable limits established by the Joint FAO/WHO Expert Committee on Food Additives.Copper levels ranged from 1.29 to 11.56 ppm, with Sangola recording the highest mean (5.30 ± 3.18 ppm), likely due to extensive use of Cu-based fungicides. Iron levels were lowest in Mohol (1.36 ± 1.22 ppm), indicating possible Fe deficiency under alkaline soil conditions. Manganese concentrations varied between 1.36 and 19.21 ppm, with Madha showing the highest mean (10.40 ± 4.74 ppm). Zinc levels, close to the critical threshold (0.6–1.2 ppm), suggest a need for targeted supplementation. Particularly high concentrations of Chromium (up to 56.08 ppm) and Nickel (up to 56.00 ppm) were observed in Malshiras and Mohol, possibly linked to effluent discharge or industrial residues. Cadmium exceeded the safe limit (>0.5 ppm) in Malshiras, while Lead concentrations were highest in the same region (6.51 ± 3.00 ppm), indicating contamination from agrochemicals or atmospheric deposition. These elevated heavy metal levels are likely associated with industrial pollution, especially from sugar factory effluents, as well as the unregulated use of fertilizers, spent wash, and press mud. The study highlights that atmospheric deposition and factors linked to the pomegranate production and marketing system may significantly contribute to heavy metal accumulation in soils, posing potential health risks through food chain contamination.