臺灣鮮奶與嬰兒奶粉中黃麴毒素M1含量及其可能之致肝癌風險

Abstract

當乳牛攝食遭到黃麴毒素B1污染的飼料後，其分泌的乳汁當中可能殘留代謝毒物黃麴毒素M1。本研究每月收集12個台灣市售三大主要品牌之鮮乳，並分兩季購買進口和台灣生產之嬰兒配方奶粉，總計160個樣本，利用固相萃取、免疫親和管柱淨化與使用液相層析/質譜/質譜儀進行定性與定量。結果顯示，在秋冬兩季鮮乳中的黃麴毒素M1有較高現象；另外低脂鮮乳中的黃麴毒素M1含量也高於全脂鮮乳。在144個鮮乳樣品中皆可檢測出微量(1.17-54.7 ng/L)黃麴毒素M1 (平均偵測極限 = 1.4 ng/L)，但僅有一個樣本含量些微超過歐盟規範的0.05 μg/L。在嬰兒奶粉方面，16個樣本皆未檢測出黃麴毒素M1 (平均偵測極限 = 12 ng/kg)。 本研究基於上述量測結果，利用WHO的方法進行鮮乳中黃麴毒素M1致肝癌風險評估。結果顯示潛在風險最高的族群為6–9歲之間的女性 (平均每年可能增加之肝癌發生數12.2)，風險最低的族群為45–64歲的男性(平均每年可能增加之肝癌發生數3.45) 。影響風險之主要因素為不同性別與年齡層間鮮乳的每日攝取量差異。國人因鮮乳中黃麴毒素M1所造成的風險相當低，屬可接受的範圍。

Pasteurized milk may contain the liver carcinogen aflatoxin M1 (AFM1) if cow ingests aflatoxin B1 contaminated feed. We collected twelve milk samples per month of three predominant brands in Taiwan; infant formulae produced domestically or imported were also purchased in two periods. A total of 160 samples were extracted by solid-phase extraction, cleaned up by immunoaffinity columns, and quantified by LC/MS/MS. Levels of AFM1 in the autumn and the winter were higher than those in the spring and the summer; interestingly, concentrations of AFM1 in low-fat milk were higher than those in whole-fat milk samples. All milk samples were detectable at trace levels (1.17-54.7 ng/L) of AFM1 (LOD = 1.4 ng/L) but there was only one sample slightly exceeded the European Union maximum level (0.05 μg/L). In contrary, AFM1 in infant formulae were all non-detectable (LOD = 12 ng/kg). The risk of liver cancer was evaluated using the WHO method. The most risky group is the 6–9 years old female (12.2 additional cases in average); the male group at 45–64 years old has the lowest risk (3.45 additional cases averagely), and this would result from their lower milk consumption than other groups. Consequently, the liver cancer risk is low for Taiwan people via milk ingestion of AFM1.