ABSTRACT
Arsenic is found on the Earth’s crust and its concentration varies in the environment. It has 0.0001 percent of abundance and exists with the ores of lead, gold and copper in nature. Its concentration is relatively lower in different samples. For example, As concentration is < 4.0 µg/L in river and marine waters, < 200 µg/L in sediment pore waters, ~ 5.0 mg/ kg in unconsolidated sediments and ~ 7.0 mg/kg in soils (Smedley and Kinniburgh 2002). Arsenic levels may increase in the environment by weathering and dissolution of arsenic-containing minerals in surface and waters (Chowdhury et al. 2000). In addition, it is known that arsenic is introduced into the environment by anthropogenic activities. The principle
1Department of Chemistry, Middle East Technical University, 06800 Ankara, Turkey. Email: sbora@metu.edu.tr 2Department of Chemistry, Dicle University, 21280 Diyarbakir, Turkey. aEmail: iaydin@dicle.edu.tr bEmail: ekilinc@dicle.edu.tr cEmail: faydin@dicle.edu.tr *Corresponding author
anthropogenic sources are the base metal smelters, mining of arsenic ores (Krysiak and Karczewska 2007, Palumbo-Roe and Klinck 2007) and wastes from arsenic-processing plants. Moreover, in the poultry and livestock industries, several phenyl arsenical compounds have been used as feed additives to prevent coccidiosis and enhance animal growth. Poultry or livestock excrete most of the arsenic in the feed and then arsenic is easily passed into the soil because of the use of poultry litter as a type of fertilizer (Stolz et al. 2007, Garbarino et al. 2003).
