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The analysis of 252 food samples (UK-produced and imported) purchased from a variety of retail outlets in the UK was undertaken for the presence of perfluorooctanesulphonic acid (PFOS), perfluorooctanoic acid (PFOA) and nine other perfluorocompounds (PFCs). A limit of quantification (LOQ) of 1 microg/kg was achieved for all target analytes, in all samples. Standard addition was used for quantification of PFC levels. All 11 of the targeted PFCs were detected in 75 individual food items. In 70% of the samples, including all meat other than offal, none of the analytes were present above the LOD. The highest levels found were 59 microg/kg perfluorooctanesulphonic acid (PFOS) and 63 microg/kg total PFCs (SigmaPFCs) in an eel sample, and 40 microg/kg PFOS (62 microg/kg SigmaPFCs) in a whitebait sample. The highest level in an offal sample was 10 microg/kg, in a wild roe deer liver. There were six samples with SigmaPFCs >15 microg/kg (fish, shellfish, crustaceans), a further seven samples with SigmaPFCs ranging 11-15 microg/kg (including a liver), nine with SigmaPFCs ranging 6-10 microg/kg (fish and livers), 31 with SigmaPFCs in the range 2-5 microg/kg (including kidneys, popcorn and processed peas) and a further 22 with SigmaPFCs close to the LOD of 1 microg/kg (including eggs and potatoes). These concentrations indicate that UK consumers are being exposed to a low level of PFC contamination from food. The estimated upper bound dietary intake of 10 ng/kg bodyweight (bw)/day of PFOS for average adult consumers is well below the 0.15 microg (150 ng)/kg bw tolerable daily intake (TDI) set by the European Food Safety Authority. The lower bound adult dietary intake estimate of 1 ng/kg bw/day is similar to estimates undertaken and reported in countries such as Canada, Germany and Spain.

The use of anabolic substances is prohibited in food-producing animals throughout the European Union. No method is available to reliably detect the misuse of natural hormones in cattle. A method was developed to detect the abuse of testosterone in cattle fattening. Synthesized testosterone is rather depleted in the (13)C/(12)C ratio. Hence, the method is based on gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) analysis of urine. To select testosterone metabolites and endogenous reference compounds (ERC), the concentration of urinary steroids of cattle was investigated. Dehydroepiandrosterone and androst-5ene-3beta,17alpha-diol were chosen as ERCs to show endogenous (13)C/(12)C ratios. Etiocholanolone and 5alpha-androstane-3beta,17alpha-diol were chosen as the most important testosterone metabolites. Other metabolites known from literature like epitestosterone were less promising. In principle, GC/C/IRMS is a nonspecific method because finally carbon dioxide is analyzed. Therefore, a dedicated cleanup procedure for the selected steroids was developed. By means of proposed confidence intervals in the isotopic composition of ERCs and metabolites, the administration of testosterone to cattle could be detected reliably. Differences of up to 11 per thousand on the delta-scale between ERC and testosterone metabolites were found after testosterone administration, whereas endogenous differences did not exceed 2 per thousand.

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