Cases reports: Unintended anti-doping rule violation after dorzolamide use several months prior to a doping control

Case Report: A case study of positive doping control by animal-to-human drug transfer after an athlete administered medicine in spray format, containing clostebol acetate, to a pet dog

The presence of a doping substance in an athlete's biological sample may not be only related to intentional pharmacological support. The unintended use of a prohibited substance may be due various reasons. This paper describes the case of a Polish canoeist preparing for the 2024 Summer Olympics in Paris who presented a positive doping test result, as a consequence of administering medication to her injured dog. The athlete used a Trofodermin cutaneous spray (containing clostebol acetate) for pet treatment, which resulted in human transfer during close contact and subsequent detection by doping authorities. To bolster the athlete's defense, it was essential to substantiate the scenario of an unconscious violation of anti-doping rules with scientific evidence. Hence, the decision was made to analyze and compare samples of the athlete's hair and her dog's fur. This investigation confirmed that clostebol absorption occurred through the skin of the hands, transfer during sleeping with the dog on the same bedding and/or inhalation (during the application of the medication, which was dispensed to the animal's paws). This defense was accepted by the Court of Arbitration for the Sport Anti-Doping Division, which subsequently found that the athlete committed an anti-doping rule violation, but under circumstances that amounted to a "no fault" scenario.

An innovative electrochemical sensor for brinzolamide detection in athletes' urine using a mercury-phen complex: a step forward in anti-doping

Brinzolamide (BRZ) is an antiglaucoma drug also used by athletes for doping purposes; therefore, it is prohibited by the World Anti-Doping Agency. Consequently, the presence of BRZ or its metabolites in athletes' urine constitutes a violation of anti-doping rules. The current work presents a novel electrochemical method that assesses the effectiveness of mercury oxide nanoparticles (HgO-NPs) and a mercuric chloride-1,10-phenanthroline complex (HgCl2-Phen complex) as sensors for BRZ analysis. A comparative analysis revealed that the synthesized HgCl2-Phen complex exhibited superior sensitivity and efficiency in determining BRZ levels. The properties of the modifiers were extensively characterized using elemental analysis, X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM). Furthermore, electrochemical characterization was conducted using square wave voltammetry (SWV), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The electrode showed a good response for SWV evaluations of BRZ in a concentration range of 0.1 to 6.0 μmol L-1, with very low limits of detection (0.01 μmol L-1) and quantitation (0.031 μmol L-1). The method's applicability was validated by detecting BRZ in urine samples from healthy human volunteers and in pharmaceutical eye drops. Additionally, the practical effectiveness of the method was assessed using the blue applicability grade index (BAGI). The key advantages of this sensor include its simple manufacturing process, as well as its remarkable sensitivity and selectivity.

Adverse analytical finding due to red blood cells transfusion: A rare case involving the diuretic dorzolamide

Early November 2020 an Olympic gold medal winner returned during an out-competition control an adverse analytical finding for dorzolamide, a diuretic mostly used to treat glaucoma. Estimated urine concentrations were 2.2 and 1.6 ng/ml in the A and B specimens, respectively. As the athlete denied any use of dorzolamide, a complex forensic investigation was suggested. It revealed that the athlete was severely injured during a car crash 6 months before where he received 2× 500 ml of red blood cells transfusion. One of the blood donors declared using dorzolamide. A plasma aliquot, stored for legal purposes, was tested by LC-MS/MS several months later and contained 4.3 ng/ml of dorzolamide. Given the very long half-life of the drug, up to 150 days and its reported incorporation into erythrocyte, it was accepted by the French antidoping administration (AFLD) that the source of contamination was this blood transfusion and that the antidoping rule violation was unintended.

Annual banned-substance review: Analytical approaches in human sports drug testing 2020/2021

Most core areas of anti-doping research exploit and rely on analytical chemistry, applied to studies aiming at further improving the test methods' analytical sensitivity, the assays' comprehensiveness, the interpretation of metabolic profiles and patterns, but also at facilitating the differentiation of natural/endogenous substances from structurally identical but synthetically derived compounds and comprehending the athlete's exposome. Further, a continuously growing number of advantages of complementary matrices such as dried blood spots have been identified and transferred from research to sports drug testing routine applications, with an overall gain of valuable additions to the anti-doping field. In this edition of the annual banned-substance review, literature on recent developments in anti-doping published between October 2020 and September 2021 is summarized and discussed, particularly focusing on human doping controls and potential applications of new testing strategies to substances and methods of doping specified in the World Anti-Doping Agency's 2021 Prohibited List.