ABSTRACT
Pollution by different chemical species remains an important environmental issue. The increasing demand for chemical surveillance in environmental protection and in many industrial processes has created the need for remediation, with features such as high selectivity, sensitivity, reliability, and sturdiness. The presence of Cd(II), Hg(II), Pb(II), Ni(II), Cr(II), As(IV), some pesticides and surfactants such as zinc(II) dimethyldithiocarbamate, and cetyltrimethylammonium bromide, respectively, in potable water above the permissible limit is harmful to human beings. The various chemical species with their harmful effects are discussed as follows:
Cadmium is a toxic heavy metal that mainly appears in the environment due to industrial processes. Cadmium strongly adsorbs to organic matter in soils. The National Institute of Occupational Safety and Health (NIOSH) has set the danger to life and health level (IDLH) as 9 mg/m3. The U.S. Environmental Protection Agency (EPA) has found cadmium to potentially cause the following health effects when people are exposed to it at levels above the minimum concentration level (MCL) for relatively short periods of time: nausea, vomiting, diarrhea, muscle cramps, salivation, sensory disturbances, liver injury, convulsions, shock, and renal failure. In the long term, cadmium has the potential to cause the following effects from a lifetime of exposure at levels above the MCL: kidney, liver, bone, and blood damage (Rezaei et al. 2008). The major sources of cadmium exposure are the smelting process, electroplating, manufacture of cadmium alloys, and production of nickelcadmium batteries and welding.
