Bioaccumulation and Ecological Risk Assessment of Heavy Metals in the Soil and Wild Rats in Riyadh, Saudi Arabia
Abeer A. Al-habash
Biology Department, Faculty of Applied Sciences, Umm Al-Qura University, Mekkah, KSA
Khadiga G. Adham
Zoology Department, Faculty of Science, King Saud University, Riyadh, KSA
Promy V. Lopez
Zoology Department, Faculty of Science, King Saud University, Riyadh, KSA
Keywords: Riyadh, Rattus rattus, Soil, Heavy metals, Pollution, Antioxidants, Oxidative stress.
Abstract
The present study aimed to analyze the impact of environmental contamination on metal accumulation and oxidative stress in wild rats, Rattus rattus, collected from metal-polluted areas in the vicinity of Riyadh Region, Saudi Arabia.Soil samples and wild rats were collected from four locations (Dhurma, Kharj Road, Al Muzahmiyah and Laban Valley ) that differ in their extent of pollution load. However, Laban Valley was taken as a reference site in this study . High concentrations of heavy metals (cadmium, lead and zinc) were recorded in soil and tissues ( liver, kidney and hair) of animals collected from Dhurma , the site with high anthropogenic pressure. Moreover, a significant increase in the level of liver malondialdeyhde (MDA) coupled with an inhibition of the activity of superoxide dismutase (SOD), catalase (CAT), Glutathione Peroxidase(GPx), Glutathione Reductase (GR) and Glutathione-S-Transferase (GST) were recorded in Dhurma followed by Kharj Road and Al Muzahmiyah compared to the reference site.From these results , it could be concluded that that the selected biomarkers are useful for the assessment of pollution impacts in natural environments and the small wild animal R. rattus can be used as a bioindicator model for metal toxicity in an arid environment.