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The control of food additives in order to protect the best consumer health and to limit fraudulent practices in the field of sports is essential. Fewer studies have been described in literature for the screening of steroids in dietary supplements.The aim of this work is to develop a simple, cost-effectiveness and qualitative analytical method allowing the achievement of the widest possible use of GC-MS than LC-MS in our doping control Laboratory for the screening of steroids in dietary supplements.During our analysis, several difficulties were occurred. Extraction method was proved to be the most problem due to the different matrixes and that steroids are presented at lower levels. The scope of conventional GC-MS is limited for nonvolatile and thermally labile compounds.Our goal is to overcome all the challenges affecting both the extraction procedure and GC-MS analysis. Our strategy includes first development of liquid-liquid extraction method then analysis by GC-MS of the TMS-derivatives.The developed method was validated then applied to the research of steroids in commercially dietary supplements. One of the monitoring sample was positive to methandienone. Our analytical method can be beneficial for screening of AAS in dietary supplements from liquid and solid forms.Several studies have highlighted that nutritional supplements may contain undeclared anabolic steroids that are banned by the International Olympic Committee/World Anti-Doping Agency. Any kind of abuse with these drugs is extremely dangerous because of their side effects. Thus, the control of food additives in order to protect the best consumer health and to limit fraudulent practices in the field of sports is essential.This paper describes a simple and effective qualitative gas chromatography-mass spectrometry (GC–MS) method to detect anabolic androgenic steroids (AAS): androsterone, nandrolene, dehydroepiandrosterone, 5α-androstane-3β, 17β-diol, dihydrotestosterone, testosterone, methenolone acetate, methandienone, boldenone and fluoxymesterone, in food supplements. Methyltestosterone was used as internal standard. Target compounds were extracted with a mixture of N-pentane and di-ethylether (7.5:2.5, v/v). A good extraction recovery was obtained by our method for all the AAS (R > 88%). Crude extract was derivatized with N-methyl-N-trimethylsilyl-trifluoracetamide. Separation was performed on a GC connected to quadrupole MS detector using a 5% phenylmethylsiloxane fused silica capillary column (30 m × 0.25 mm i.d.; film thickness, 0.25 μm). Helium was used as carrier gas with a flow rate of 0.3 μl min−1 (measured at 6.1 psi 190 °C). The MS was operated in electron ionization mode (70 eV) and in selected ion monitoring (SIM). The mass spectra of the standard compounds were acquired in full SCAN mode (50–700 m/z) by infusion of a reference solution at 50 μg/ml. Three higher diagnostic ions were monitored for each compound of interest.All AAS get separated with good peak shapes and resolution factor. The total analysis time by our optimised method was only 20 min. The developed method was validated according to Laboratories International Standard regulations for specificity, precision in both liquid and solid matrixes, and memory effect. The Tolerance Interval was judged true. The limit of detection was about 10 ng/g for solid samples and 10 ng/ml for liquid samples. The developed method was then applied to the research of steroids in nine Tunisian commercially dietary supplements using for each compound of interest SIM mode for screening then SCAN mode for confirmation. One of the monitoring samples was positive to methandienone not declared on the label. Our analytical method can be beneficial for AAS screening in dietary supplements.