Arsenic is one of the most important toxic trace elements [1]. Chemical hydride generation (CHG) is a well-established technique for the determination of arsenic (As) [2]. In the present research, a funnel assisted-headspace liquid phase microextraction technique has been used in combination with hydride generation for determination of arsenic (As) by UV–Vis spectrophotometry. The method is based on the reduction of As to Arsine (AsH3) in acidic media by sodium tetrahydroborate (NaBH4) followed by its subsequent reaction with silver diethyldithiocarbamate (AgDDC) to give an absorbing complex at 510 nm. The complexing reagent (AgDDC) has been dissolved in a 50:50 (%v/v) chloroform/chlorobenzene microdroplet and exposed to the generated gaseous arsines via a reversed funnel in the headspace of the sample solution. Effect of several operating parameters affecting the performance of the method has been examined and optimized. Acetonitrile solvent has been added to working samples as a sensitivity enhancement agent. Under the optimized operating conditions, the detection limit has been obtained to be 0.2 ng mL-1 (based on 3sb/m; nb=8) and the calibration curve was linear in the range of 0.5-12 ng mL-1. The relative standard deviation for eight replicate measurements was 1.9%. Also, the effects of several potential interferences have been studied. The accuracy of the method was validated through the analysis of standard reference material JR-1 geological sample. The method has been successfully applied for determination of arsenic in raw and spiked soft drink and water samples with recoveries ranging from 90 to 97%.

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