4. Conclusion
Analysis of total arsenic in drinking water requires the reduction of As(V) species to As(III) for accurate quantification. We have found that the sample can be prepared in 3M HCl and prereduced with 1% KI for 30 min at room temperature and then aspirated in the instrument—AAS(VGA). Alternatively KI (10%) can be mixed in sodium borohydride solution for use in reduction channel and the sample prepared in 6M HCl
can be aspirated in the VGA directly. Thus using both the methodologies analysis of arsenic can be performed precisely and accurately at ppb level. While in the prereduction method time could be saved, working with lower acid concentration was possible in the latter methodology when the sample was directly aspirated in the instrument compared to what has been reported earlier.