ヒジキに含まれるヒ素の健康リスク評価

抄録

The toxicity and carcinogenicity of arsenic depend on its species. Individuals living in Japan consume much seafood that contains high levels of organoarsenics. Speciation analysis of urinary arsenic was performed for 210 Japanese male subjects without occupational exposure using HPLC-ICP-MS. The median values of dimethylarsinic acid(DMA)and arsenobetaine(AsBe)were 42.6 and 61.3 μgAs/L, respectively. These findings indicate that DMA and AsBe levels in Japan are much higher than those found in Italian and American studies. It appears that the high levels of DMA and AsBe observed in Japanese may be due in part to seafood intake. Hijiki(hizikia fusiforme)is a traditional food and used as a part of a balanced diet in Japan for centuries. In 2004 the UK Food Standards Agency advised not to eat Hijiki seaweed. To clarify the risks of Hijiki ingestion, a 42-year-old male volunteer ingested 825 μg of inorganic arsenic compounds contained in eight servings of commercial Hijiki food, after refraining from eating seafood for 3 months. The total amounts of sodium arsenate, sodium arsenite, monomethylarsonic acid and DMA excreted in urine over 50 h were 11.2, 31.8, 40.9 and 104.0 μgAs, respectively. Long-term ingestion of Hijiki might elevate the risk of carcinogenicity.