Bioaccumulation and oxidative stress induction of heavy metals in ecosystem of an urban region: A case study to assess ecotoxicological risk on freshwater mollusk, Lanistis carinatus in Kafr El-Zayat region, Egypt
Bioaccumulation pattern of heavy metals (HMs) emitted from urban region of Kafr El-Zayat city was studied in attributing to oxidative stress induction in freshwater mollusk, Lanistis carinatus. Regional distribution of HMs in water, sediments, mollusk's tissues in collected samples from sites near industrial units showed significantly differences, respect to reference site (rural). Measured metals: cadmium (Cd), lead (Pb), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe) in the tissues were greater than those found in water and sediments, representing bioconcentration factors (BCFs) in range (0.83-49.13) during summer and (0.00-24.85) during winter for ratio of tissue/water. However, its ranged (0.09-29.25) during summer and (0.00-8.05) during winter for ratio of tissue/sediments. On the other hand, levels of malondialdehyde (MDA) in digestive glands of mollusk from contaminated sites were greater than those of reference site. Moreover, significantly alterations were recorded for catalase (CAT), glutathione peroxidase (GPx), and carbonyl protein (CP) in a positively correlation with measured HMs. From all findings, it was obtained that use of cumulative biomarkers with BCF may provide diagnostic tool to assess ecotoxicological risk in ecosystem of industrial and urban regions.