Evaluation of Pollution with Copper and Cadmium in Soil Surround the Diyala State Company
Abstract
Background: One of the biggest environmental issues of the modern era is heavy metal contamination. These contaminants are frequently produced by industrial processes and can build up in soil before invading the environment and possibly endangering human health. This study used the pollutant load index (PLI), contamination factor (CF), and geoaccumulation index (Igeo) to evaluate soil contamination by copper and cadmium in the vicinity of the Diyala State Company. Methods: Soil samples were collected from four main directions (north, south, east, and west) and at different distances from the company (100, 500, 1000, and 2000 m) during the period from June to August 2024. Cadmium and copper concentrations were determined, and the degree of soil contamination was evaluated using Igeo, CF, and PLI. Results: Cadmium concentrations ranged from 1.08 to 2.70 mg/kg, while copper concentrations ranged from 3.70 to 8.84 mg/kg. Igeo values for cadmium ranged from 0.866 to 2.167, whereas those for copper ranged from 0.032 to 0.076. CF values for cadmium ranged from 4.32 to 10.80, while those for copper ranged from 0.15 to 0.38. PLI values ranged from 0.97 to 1.70. The results demonstrated spatial variation in pollution levels among the sampling sites. Overall, cadmium showed moderate to high levels of contamination, whereas copper showed minimal contamination and the study area was largely unpolluted with respect to copper. Conclusions: The findings suggest that industrial activities associated with the Diyala State Company may contribute to heavy metal contamination of surrounding soils, particularly by cadmium. The Igeo, CF, and PLI indices indicated substantially greater cadmium accumulation than copper, with an overall moderate level of soil pollution. Regular environmental monitoring, improved waste management and treatment practices, and the application of appropriate remediation strategies, including phytoremediation, are recommended to limit additional metal accumulation and reduce possible environmental and human-health risks.