市售魚肉中不同砷物種之檢測   全文下載

Arsenic Speciation in Fish on the Market

利用快速蘇氏萃取法及HPLC-ICPMS 建立水產品中砷酸甜菜鹼、雙甲基砷、單甲基砷、亞砷酸及砷酸同時檢測方法（回收率分別為：95、111、83、85 及84%）。檢測鮪魚肉（BCR 627, tuna fish）及鯊魚肉（DORM-2, dogfish muscle）等標準參考樣品中砷酸甜菜鹼之回收率分別為：95 及90%，檢測極限經推估為0.02 mg/kg。檢測市售60 件水產品（頭足類20件、小型魚類16 件及大型魚類24 件）之結果顯示，水產品中可檢測出54至100% 之砷酸甜菜鹼，微量砷酸（平均含量為0.10 mg/kg），檢測不到雙甲基砷、單甲基砷及亞砷酸。頭足類、小型魚類及大型魚類中砷酸甜菜鹼之含量分別為5.42、1.57 及1.54 mg/kg。經由取食水產品而攝入砷之安全評估結果，顯示總砷攝取量為30.6 μg/kg body weight/week，高於每人每週容許攝取量15 μg/kg body weight/week（無機砷），但其中87% 為對人體無毒之砷酸甜菜鹼，因此尚在安全範圍內。"

Arsenic speciation in fish samples on the market was analyzed using gradient anion exchange high performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICPMS) detection. Freeze-dried samples were extracted by methanol and water mixture (8:2 v/v) with a high-speed Soxhlet system; the concentration of arsenobetaine (AsB), dimethylarsinic acid (DMAA), monomethylarsonic acid (MMAA), arsenate (As(V)) and arsenite (As(III)) in the extract were then determined using HPLC-ICPMS. The method for determining arsenobetaine concentration was confirmed using standard reference material (SRM) of BCR 627 (tuna fish) and DORM-2 (dogfish muscle); recovery rates were 95 and 90%, respectively. The arsenic compounds in 60 market-ready fish muscle samples were investigated. The predominant arsenic compound found in samples was AsB. Arsenate was detected in low concentrations (ranged in 0.02–0.34 mg/kg As for fresh weight), whereas DMAA, MMAA and arsenite content were undetectable. Average AsB content in cephalopods, small fish and large fish were 5.42, 1.57 and 1.54 mg/kg As (fresh weight), respectively. The weekly intake of As was calculated based on the consumption of fish by Taiwanese residents. The calculated results demonstrated that the intake is 30.6 μg/kg (total As) body weight/week, higher than the acceptable weekly intake of 15 μg/kg body weight/week for inorganic arsenic that was suggested by WHO. However, around 87% of As in fish muscle was AsB. AsB is non-toxic and non-carcinogenic to humans, and is rapidly excreted after ingestion. Therefore, intake of fish muscle is low risk based on investigation results.