Heavy Metal Chronicles: Assessing Antioxidant Enzyme Activity and Oxidative Stress in Perionyx Excavates Exposed to Contamination

Abstract

This study aimed to investigate the toxic effects of heavy metals, specifically mercuric chloride, copper sulfate, zinc sulfate, and their combination, on the activity of antioxidant enzymes in the earthworm species Perionyx excavates. The experiment involved exposing the worms to varying concentrations of the heavy metals. The concentrations of mercuric chloride ranged from 25 to 30 mg/kg of dry soil, copper sulfate concentrations ranged from 60 to 150 mg/kg of dry soil, and zinc sulfate concentrations ranged from 140 to 350 mg/kg of dry soil. The exposure duration was set at 5 days. Throughout the experiment, the activities of three antioxidant enzymes, namely Superoxide Dismutase (SOD), Catalase (CAT), and Glutathione-S-transferase (GST), were monitored. The results demonstrated a dose-dependent and time-dependent increase in the activities of these enzymes. Among the heavy metals tested, mercuric chloride exhibited the highest toxicity at its maximum concentration. Furthermore, the combination of copper sulfate and zinc sulfate at their highest concentrations also displayed significant toxicity. In conclusion, this study highlights the detrimental effects of heavy metal exposure on the antioxidant enzyme activity in Perionyx excavates. The findings emphasize the potential ecological risks associated with heavy metal contamination and the importance of understanding the biochemical responses of organisms to such pollutants. Further research is warranted to elucidate the underlying mechanisms and long-term consequences of heavy metal toxicity in earthworms.