title: Transfer of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) from contaminated feed into milk and meat of sheep: pilot study.
abstract: 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).
authors.affiliation: Federal Institute for Risk Assessment (BfR), Max-Dohrn-Str. 8-10, 10589, Berlin, Germany. janine.kowalczyk@bfr.bund.de
authors.forename: Janine
authors.initials: J
authors.lastname: Kowalczyk
authors.forename: Susan
authors.initials: S
authors.lastname: Ehlers
authors.forename: Peter
authors.initials: P
authors.lastname: Fürst
authors.forename: Helmut
authors.initials: H
authors.lastname: Schafft
authors.forename: Monika
authors.initials: M
authors.lastname: Lahrssen-Wiederholt
mesh_terms: D017738:Alkanesulfonic Acids / Q000032:analysis / Q000493:pharmacokinetics*; D000818:Animals; D002210:Caprylates / Q000032:analysis / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005466:Fluorocarbons / Q000032:analysis / Q000493:pharmacokinetics*; D005506:Food Contamination / Q000032:analysis*; D005858:Germany; D007220:Industrial Waste / Q000032:analysis; D008460:Meat / Q000032:analysis*; D008892:Milk / Q000737:chemistry*; D010865:Pilot Projects; D012756:Sheep / Q000378:metabolism*; D012820:Silage / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis / Q000493:pharmacokinetics*; D014018:Tissue Distribution
chemical_list: D017738:Alkanesulfonic Acids; D002210:Caprylates; D005466:Fluorocarbons; D007220:Industrial Waste; D012989:Soil Pollutants; C023036:perfluorooctanoic acid; C076994:perfluorooctane sulfonic acid