Bioindication of Beetles and Spiders for the Ecotoxicological Study of the Impact of Heavy Metals and their Interaction with Detoxification Enzymes

Document Type : Original Article

Authors

1 Zoology Department, Faculty of Science, Al-Azhar University, Cairo, Egypt.

2 Zoology Department, Faculty of Science, Damietta University, Egypt.

Abstract

The utilization of beetles and spiders has recently become a great mean for a fast and accurate trend in the ecotoxicological study. Tenebrionid beetle (Mesostena angustata)and carnivorous spider(Galeodes arabs)were chosen as bioindicators to evaluate the industrial impact in El Sadat industrial region, Menofia, Egypt. Three categories of industries; light, medium, and heavy industries compared with the natural environment were selected. Bioaccumulation of heavy metal body burden and the interacted activity of detoxification enzymes: Acetylcholinesterase and Lactate Dehydrogenase were assessed in both species during four successive seasons. Results showed significant variations in the seasonal and spatial bioaccumulation of heavy metals in tested species. Summer was the highest season with heavy metal accumulation amongst the heavy industries, followed by the medium industries. That was confirmed later with the Metal pollution index. M. angustata was more susceptible to heavy metal accumulation than G. arabs. The major accumulated elements were; iron and zinc opposite to cadmium in both species. Consequently, the increased activity of both detoxifying enzymes revealed they are related to the bioaccumulation of heavy metals, particularly in the zone of heavy industries during the summer season. For confirmation, the significant positive relationship was between total accumulated heavy metals and detoxification enzyme activity.

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