Journal of Environmental Biology

Risk assessment of heavy metal contamination in soil and wild

Libyan jird Meriones libycus in Riyadh, Saudi Arabia

Author Details

Khadiga G. Adham

(Corresponding author)

¹Zoology Department, College of Science, Women Students Medical Studies & Sciences Sections,

King Saud University, Riyadh 11495, Saudi Arabia

²Zoology Department, College of Science, Alexandria University, Moharram Bey, Alexandria 21511, Egypt

e-mail: kadham@ksu.edu.sa, kadham_100@yahoo.com

Nadia A. Al- Eisa????

Zoology Department, College of Science, Women Students Medical Studies & Sciences Sections,

King Saud University, Riyadh 11495, Saudi Arabia

Manal H. Farhood

Zoology Department, College of Science, Women Students Medical Studies & Sciences Sections,

King Saud University, Riyadh 11495, Saudi Arabia

Publication Data

Paper received:

17 May 2010

Revised received:

10 November 2010

Accepted:

08 January 2011

Abstract

This study was undertaken to document the impact of heavy metal pollution on the Libyan jird, Meriones libycus and to contribute to an environmental impact statement for the rapidly growing City of Riyadh. All metal concentrations in surface soil of a polluted site (within Riyadh City) were higher than those from a reference site (outside the city). Although Pb declined versus earlier reports on Riyadh soil, Cd (0.97 ?g g^-1) and Hg (0.28 ?g g^-1) were above some of the most stringent quality guidelines (0.07- 0.62 ?g g^-1 for Cd and 0.14- 0.18 ?g g^-1 for Hg). Metal distribution in M. libycus proved site-related and organ-specific, recognizing a higher affinity of most tested metals towards the kidneys, liver and brain than the lung and heart. The comparatively lower site-specific accumulation of Pb in soft tissues was attributed primarily to its major hypothetical accumulation in bones, whereas, the transition rate of Hg from the liver was suggested to be lower to the brain than to the kidneys. Although a non hazardous status was assumed for Cu (11.27-13.16 ?g g^-1) and Hg (up to 0.207 ?g g^-1) in tissues of M. libycus, a potential risk was imposed by mean tissue concentrations of Cd (up to 3.29 ?g g^-1), Ni (up to 1.48 ?g g^-1) and Pb (up to 1.94 ?g g^-1). On the grounds of the significantly higher metal levels in polluted soft tissues versus reference subjects, Libyan jirds possess high exposure potential and can be useful biomonitors of environmental metal contamination.

Key words

Metal toxicity, Libyan jird, Organ accumulation, Bioindicator

Copyright ? 2011 Triveni Enterprises. All rights reserved. No part of the Journal can be reproduced in any form without prior permission. Responsibility regarding the authenticity of the data, and the acceptability of the conclusions enforced or derived, rest completely with the author(s).