The nutritional value and preliminary risk assessment of major and trace elements accumulated in 8 edible seaweeds

16 major and trace elements content of 8 edible seaweeds were determined by ICP-AES after wet digestion to compare the nutritional value and pollution level between Cyanophyta (blue), Chlorophyta (green), Rhodophyta (red), Phaeophyta (brown) species. The concentration changes of trace elements in seaweeds had some differences from four species, but the concentration distribution tendency of trace elements was similar. Major elements (K,Ca,Na,Mg,P) and functional elements (Fe,Mn,Zn,Cu,Se,Cr) were abundant in Cyanophyta (blue) and Phaeophyta (brown) species, these two species, however, accumulated Al selectively. The pollution levels of toxic elements like As, Pb and Hg in most seaweeds from this study demonstrated that the cultivation aquatic eco- environments were relatively safe. In this paper, Nostoc commune var. Flagelliforme (Cyanophyta) abounds in Fe, Zn and major elements, moreover the concentration of potentially toxic elements were relatively low. The second was Phaeophyta species, especially Laminaria japonica Aresch. Porphyra yezoensis Ueda (Rhodophyta) shows the lowest nutritional value.