A simple method was developed for speciation and spectrophotometric determination of inorganic As(III) and As(V) using ‎an electrochemical hydride generation technique. For speciation of As(III) and As(V), a graphite rod was used as cathode to reduce ‎As(III) to AsH3, the rod was then replaced with a tin-lead alloy wire for reducing As(V) to AsH3. The spectrophotometric ‎determination was based on the reaction of AsH3, with silver diethyldithiocarbamate to give an absorbing complex at 510 nm. ‎Under the optimized conditions, the calibration curves were linear over the ranges of 0.1 - 5 ug ml-1 for As(III) and of 0.5 - 4.0 ug ‎ml-\' for As(V). The concentration detection limits of 0.02 and 0.06 ug ml-1 were achieved for As(Ill) and As(V), respectively. The ‎relative standard deviations for five replicate speciation and determination of 3.0 ml-1 As(III) and As(V) were 0.8 and 7.2%, ‎respectively. The accuracy and recovery of the method were evaluated by analyzing tap water spiked with As(lll) and As(V).‎

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