Abstract:

The samples were pretreated by wet nitration and HCl extraction，and the contents of As in marine algae were determined by HG-AFS．The analytical conditions were optimized by orthogonal designing．Under optimum conditions，the detection limit of total arsenic，inorganic arsenic，trivalent arsenic were 0.05799 μg/L，0.03351 μg/L and 0.05286 μg/L, respectively. The correlative coefficient of linear regression equation was over 0.9994 and the precisions of total arsenic and norganic arsenic were 1.33% and 2.94% (RSD, n=5), respectively . The average recoveries were 102.95% and 103.40% (n=5). The contents of total arsenic and inorganic arsenic in 11 kinds of marine algae samples varied within the range of 5.15 to 118.72 μg/g and 1.05 to 89.19 μg/g. Trivalent arsenic ranged from 0.31 to 27.11μg/g. The contents of inorganic arsenic in the 11 kinds of marine algae samples were beyond GB/T 2762 — 2005 and GB/T 19643 — 2005 standard except for amethyst algae．

Key words: hydride generation-atomic fluorescence spectrometry, marine algae, inorganic arsenic