Abstract
A close-vessel microwave dissolution method for the determination of arsenic and selenium in lake sediments and mine tailings is compared with a conventional hot plate digestion technique. The utilization of a mixture of HC1-HNO3-HF allowed the best recovery of As (105% and 100%) and Se (109%) present in certified reference materials analysed by Hydride Generation Atomic Absorption Spectrometry when the hot plate technique only led to poor recovery of both elements. Relationships between the total concentration of arsenic and total iron and between the total concentration of selenium and total sulfur have been observed in surficial lake sediments and mine tailings.