Arsenic is a non-metallic constituent, present naturally in groundwater due to some minerals and rocks. Arsenic is not geologically uncommon and occurs in natural water as arsenate and arsenite. Additionally, arsenic may occur from industrial discharges or insecticide application. World Health Organization (WHO) and Pakistan Standard Quality Control Authority have recommended a permissible limit of 10 ppb for arsenic in drinking water. The arsenic at lower concentrations can be determined in water by using high tech instruments like Atomic Absorption Spectrometer (hydride generation). The arsenic concentration at low limits of 1 ppb could not be determined easily with simple spectrophotometric technique. Therefore, Spectrphotometric technique using the silver diethyldithiocarbamate was modified to achieve the better results, up to the extent of 1 ppb arsenic concentration.
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