ABSTRACT
In the past, the determination of total element concentrations was considered to be enough for clinical and environmental analyses. However, the knowledge of chemical speciation has primary importance because the toxicity, mobility, bioavailability and bioaccumulation of elements largely depend on their chemical species (Ebdon et al. 2001). Chemical species are specifi c forms of an element defi ned as isotopic composition, electronic or
1Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O.Box 80203, Jeddah 21589, Saudi Arabia. aEmail: malsaeed@kau.edu. sa, mohammad_el_shahawi@yahoo.co.uk 2Department of Chemistry, University College, Umm Al Qura University, Makkah, Saudi Arabia. 3Department of Applied Chemistry, College of Applied Science, Taibah University, Al-Madinah Al-Munawarah, P.O. Box: 3193, Saudi Arabia. *Corresponding author
oxidation state and/or complex or molecular structure (Templeton et al. 2000). Tellurite, Te (IV) is 10 times more toxic than tellurate, Te (VI) (Huang and Hu 2008). Therefore, speciation studies are important for the accurate evaluation of pollution levels in a wide variety of samples such as water, soil and sediment.
