Studying Inorganic Arsenic, Heavy Metals, and Iodine in Dried Seaweed.

In this study, 33 different dried seaweed products were purchased in local markets in Madrid and analyzed. Arsenic, cadmium, mercury, nickel, lead and iodine were determined by inductively coupled plasma--mass spectrometry (ICP-MS) in samples previously digested in a microwave oven. In addition, inorganic arsenic (iAs) was determined by high performance liquid chromatography (HPLC) combined with microwave-assisted extraction followed by ICP-MS. Results indicate that the levels of Cd, Ni, and Pb were relevant in some of the samples, and may pose a risk to consumers. The concentrations of Hg were overall the lowest found in the samples. Hijiki seaweed (Hizikia fusiforme) contained a considerable iAs fraction, whereas all the other seaweed species contained minimal fractions. Lastly, iodine content in most of the seaweeds surpassed the tolerable daily intakes recommended by the European Food Safety Authority (EFSA), which may pose a risk to consumers. [ABSTRACT FROM AUTHOR]