Given the high intake of potatoes by the world population, reliable methodologies with very low limits of detection are needed for the determination of highly toxic elements such as arsenic. For that purpose, graphite furnace atomic absorption spectrometry could be considered one of the techniques of choice; notwithstanding the matrix effect prevented its application in arsenic determination in potatoes as

Abstract

Given the high intake of potatoes by the world population, reliable methodologies with very low limits of detection are needed for the determination of highly toxic elements such as arsenic. For that purpose, graphite furnace atomic absorption spectrometry could be considered one of the techniques of choice; notwithstanding the matrix effect prevented its application in arsenic determination in potatoes as the analytical signal was absolutely depleted. The potential interferent was searched among the mineral content. As a result, it was found that the interference presumably could be attributed to phosphate. Attempts to overcome the matrix interference by different sample digestion methodologies, chemical modification and temperature variation in the graphite furnace ashing and ashing / atomization stage respectively, were unsuccessful. Consequently, an alternative methodology for determining arsenic in potatoes using hydride generation microwave induced plasma optical emission spectrometry was developed. Limit of detection was 0.0030 mg kg-1 in fresh potatoes. The developed method is a robust, simple and low cost alternative for total arsenic safe monitoring of this highly consumed worldwide vegetable.