Validation of an Analytical Biomarker Approach for the Detection of Nandrolone Abuse in the Porcine

Chromatographia (Impact Factor: 1.44). 72(3):297-305. DOI: 10.1365/s10337-010-1652-4

ABSTRACT The use of anabolic steroids as growth promoting agents in food production is prohibited under European Union legislation,
but there is currently no internationally accepted method for detecting the abuse of the anabolic steroid nandrolone in the
porcine. Therefore, an analytical biomarker approach based on gas chromatography-tandem mass spectrometry (GC-MS-MS) analysis
of the major urinary free fraction nandrolone metabolite 19-noretiocholanolone was developed and validated. The lower and
upper limits of quantification of the assay were 25 and 3,000pgmL−1 respectively. The limit of detection was calculated as 13.2pgmL−1, which is significantly lower than previously reported methods. When applied to a population of untreated animals, 19-noretiocholanolone
distributions in boars and gilt were bimodal, with a small number of concentrations in each sex at around the 1,000pgmL−1 region and the majority of concentrations closer to the lower end of the calibration range. Statistical analysis of the data
was carried out in order to suggest screening and confirmatory threshold approaches for this steroid in the urine of boars
and gilts. The adopting of particular screening thresholds would be at the discretion of the individual regulating authorities,
but at a false non-compliance rate of 1 in 10,000 of the normal population, the suggested confirmatory thresholds (7,501.6pgmL−1 for boars and 19,200.4pgmL−1 in gilts) are able to detect the abuse of nandrolone for several weeks following administration of this steroid.

KeywordsGas chromatography–tandem mass spectrometry-Threshold-Porcine-Pig-Steroids-Nandrolone

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