Preconcentration of cadmium using amberlite xad-4 prior to atomic absorption spectrometery
Heavy metals can be considered as a unique class of environmental toxicant. They occur and persist in nature and most of them are advantageous to humans because of their vast usages in different industries, agriculture, and medicine. However, they may pose health hazards to the public because of their presence in air, water food chains as well as to the workers engaged in mining, smelting, alloy, painting, electroplating, pesticides, and the variety of industrial activities. Some heavy metals such as cadmium have a wide range of toxicities, leading to toxic effects on the renal, respiratory, and nervous nervous systems. Chronic exposure to cadmium results in renal damage. Also, long term inhalation exposure at low levels leads to decreased lung function and emphysema. Other consequences of Cd exposure are anemia, eosinophilia, and occasional ulceration of the nasal septum (Frank, 1996; Hathway et al., 1996; Bingham et al., 2004; WHO, 1998). Because, usages of this heavy metal are unavoidable, from the environmental and occupational viewpoints, study of this compound is of great interest. One of the most important aspects of metal studies is determination of such compounds in different matrices. In environmental and biological samples, either exposed compounds or their metabolites, metals are mostly present at trace level, causing major problems in their determination stages (Mc Dowall, 1989; Shahtaheri et al., 1998; Shahtaheri et al., 2005).