Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany.
Arch Environ Contam Toxicol. 2012 Aug;63(2):288-98. doi: 10.1007/s00244-012-9759-2. Epub 2012 Mar 28.
A pilot study was performed with dairy sheep to generate the first data on the transfer of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from feed into food of animal origin. Corn silage was cultivated on cropland in Lower Saxony in Germany where, as a result of illegal waste disposal in 2006, farmland was contaminated with perfluorinated alkylacids (PFAAs). Two sheep were exposed by way of PFAA-contaminated corn silage to PFOS (1.16 and 1.45 μg/kg body weight [bw]/d, respectively) and PFOA (0.43 and 0.53 μg/kg bw/d) during a period of 21 days. During the PFAA-feeding period, PFOS levels in plasma increased continuously to maximum concentration of 103 and 240 μg/L for sheep 1 and sheep 2, respectively. The PFOA plasma concentration remained low (sheep 1 = 3.3 ± 2.2 μg/L; sheep 2 = 15.6 ± 8.3 μg/L). Data indicate that urinary excretion is the primary clearance route for PFOA (sheep 1 = 51 %; sheep 2 = 55 %), whereas PFOS excretion by way of urine could not be quantified. The highest PFOS excretion (4 to 5 %) was detected in faeces. PFOS was also excreted at higher levels than PFOA by way of milk. During a period of 21 days, a total PFOS transfer into milk ≤ 2 % was calculated. Overall, total excretion of PFOS was significantly lower compared with that of PFOA (PFOS 6 %; PFOA 53 to 56 %). PFOS levels in sheep 1 and sheep 2 were highest in liver (885 and 1,172 μg/kg weight wet [ww], respectively) and lowest in muscle tissue (24.4 and 35.1 μg/kg ww, respectively). PFOA levels in muscle tissue were low for sheep 2 (0.23 μg/kg ww) and not detectable after the PFAA-free feeding period in sheep 1. A slight background load of PFOS in liver (1.5 μg/kg ww) and kidney (0.3 μg/kg ww) was detected in sheep 3 (control).
本研究以奶绵羊为实验动物，旨在探讨源于饲料的全氟辛酸（PFOA）和全氟辛烷磺酸（PFOS）向动物源食品转移的情况，为相关研究提供数据支持。实验采用的青贮饲料由德国下萨克森州农田种植的玉米制成，该农田曾因 2006 年非法倾倒废物而受到全氟烷基酸（PFAAs）污染。实验绵羊通过摄入受 PFAAs 污染的青贮饲料，在 21 天的时间里，分别摄入 PFOS（1.16 和 1.45μg/kg 体重/天）和 PFOA（0.43 和 0.53μg/kg 体重/天）。在 PFAA 喂养期间，绵羊 1 和绵羊 2 的血浆中 PFOS 浓度持续增加，最高浓度分别达到 103μg/L 和 240μg/L。而绵羊 1 和绵羊 2 的 PFOA 血浆浓度一直保持在较低水平（绵羊 1=3.3±2.2μg/L；绵羊 2=15.6±8.3μg/L）。实验数据表明，PFOA 主要通过尿液排出（绵羊 1=51%；绵羊 2=55%），而 PFOS 则无法通过尿液定量排出。通过粪便检测到的 PFOS 排泄率最高（4%至 5%）。与 PFOA 相比，PFOS 还通过乳汁以更高的水平排出。在 21 天的实验周期内，通过计算发现绵羊奶中 PFOS 的总转移量≤2%。总体而言，PFOS 的总排泄量明显低于 PFOA（PFOS 为 6%；PFOA 为 53%至 56%）。绵羊 1 和绵羊 2 的肝脏中 PFOS 含量最高（分别为 885μg/kg 湿重[ww]和 1172μg/kg 湿重[ww]），肌肉组织中含量最低（分别为 24.4μg/kg ww 和 35.1μg/kg ww）。绵羊 2 的肌肉组织中 PFOA 含量较低（0.23μg/kg ww），绵羊 1 在停止摄入 PFAA 后也未检测到 PFOA。绵羊 3（对照组）的肝脏（1.5μg/kg ww）和肾脏（0.3μg/kg ww）中均有少量 PFOS 背景负荷。
