Arsenic in the prepared edible brown alga hijiki, Hizikia fusiforme

To reduce the arsenic content of the leaves and branches of an edible brown alga, hijiki Hizikia fusiforme, the Japanese traditional washing and soaking process before cooking was shown to be effective: about 32 to 60% of the arsenic was removed from the alga at room temperature. Increasing the amount of water in which the hijiki was soaked did not affect arsenic removal. On the other hand, arsenic content decreased linearly as the temperature used to wash and soak hijiki increased from 0 to 60 degreesC. In the washed and soaked hijiki, inorganic arsenic accounts for 90% of the total arsenic and dimethylated arsenic compounds 10%. Copyright (C) 2001 John Wiley & Sons, Ltd.