Detectability of oxandrolone, metandienone, clostebol and dehydrochloromethyltestosterone in urine after transdermal application

Clostebol detection after transdermal and transmucosal contact. A systematic review

INTRODUCTION

To analyze the available evidence about the correlation between the presence of detectable amounts of clostebol metabolites in urine and the transdermal or transmucosal contact of clostebol.

CONTENT

A systematic review was performed. A systematic search was conducted in PubMed/MEDLINE, Scopus, Web of Science and the Cochrane library databases. Criteria for including studies were clinical studies reporting: (i) adult subjects; (ii) detection of urine clostebol metabolites derived from transdermal or transmucosal contact of clostebol.

SUMMARY

Seven papers pertinent to our questions were found: 3 case reports, one experimental study and 3 case reports with an experimental section for a total of 32 subjects. The median concentration of urine clostebol's metabolite 4-chloro-androst-4-en-3α-ol-17-one, M1 was 0.5 ng/mL (range 0.086-4.000 ng/mL; 25%-75 % IQ: 0.5-0.9 ng/mL) and 8.1 ng/mL (range 1.0-36.6 ng/mL; 25%-75 % IQ: 2.8-22.0 ng/mL), in subjects with indirect and direct exposure of clostebol, respectively (p=0.005).

OUTLOOK

We found consistent data that the detection of M1 in urine can be reconcilable with a transdermal or transmucosal contact of clostebol. In the cases of indirect exposure, the urine concentrations of M1 seem to be far lower than the concentrations found in case of direct exposure.

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.

Determination of clostebol residues in the urine of slaughter animals using liquid chromatography-tandem mass spectrometry

Introduction

Synthetic anabolic hormones, which may pose a potential risk to human health, should not be used in fattening food-producing animals. Because of the hormonal effects they cause, growth-promoting compounds are banned by legislation in the EU for use in animal husbandry. Consequently, all EU member states are required to conduct monitoring tests on the content and residues of these compounds in prescribed biological matrices to ensure the safety of food consumers. The aim of this research was to develop a liquid chromatography-tandem mass spectrometry method for the detection of the residue of one such anabolic hormone, clostebol in food animal urine.

Material and Methods

Clostebol and its marker metabolite residues were determined by a method involving enzymatic hydrolysis, isolation of compounds from urine on a C18 solid-phase extraction (SPE) column, purification of the extract by liquid-liquid extraction using n-pentane and a NH2 SPE column, and detection by liquid chromatography-tandem mass spectrometry.

Results

No traces of this anabolic steroid hormone or its metabolites were found in any of the samples tested. The method was validated in accordance with the current requirements for confirmatory methods, and the determined parameters of the decision limits necessary for assessing sample compliance met the specified criteria.

Conclusion

In 2023, the method was introduced for testing under the National Control Plan in Poland. Up to July 19, 2024, 53 urine samples from different animal species had been tested.

Unravelling the threat of contamination in elite sports: Exploring diverse sources impacting adverse analytical findings and the risk of inadvertent exposure to prohibited substances

In recent years, increasing concerns have emerged regarding athletes being exposed to various sources of contamination that could result in an adverse analytical finding (AAF), which is considered a positive doping test and may lead to the athlete's sanction. This review aims to examine the potential sources of contamination. Firstly, exogenous sources such as food, water, supplements, and medications will be described, along with endogenous sources, primarily arising from the athlete's physiological condition via the biotransformation of Medications. Finally, other hypothetical contaminations arising from sample collection procedures, poor transport or storage, and laboratory conditions will be discussed. Despite some legislative efforts to regulate the production of food and supplements, contamination remains a significant concern in the context of anti-doping, necessitating athletes to stay vigilant against the risks of inadvertent uptake of illicit products. Increased knowledge of the potential sources of contamination is essential for all parties involved in the fight against doping, including athletes, support personnel, legitimate supplement product manufacturers, and the anti-doping and scientific community. Such insights can contribute to developing the most effective strategy for preventing contamination and, most importantly, reducing the risk of inadvertent AAFs.

Clostebol and sport: about controversies involving contamination vs. doping offence

Clostebol, the 4-chloro derivative of testosterone, available as Over The Counter product in pharmacies and drugstores in several countries, is mostly commercialized as a cream or spray in the form of acetate ester. As other anabolic steroids, clostebol is listed as a prohibited substance by the World Anti-Doping Agency (WADA). Controlled transdermal application of clostebol acetate has been reported to produce detectable amounts of its metabolites in urine, even after a single exposure. Indeed, a low urine concentration can be interpreted as the tail of a drug voluntarily used to enhance performance or a direct consequence of a contamination. The increased number of adverse analytical findings (AAFs) involving clostebol reported in the last years should lead to highlight the need for athletes to be warned against personal and /or accidental use/exposure of dermal preparation containing this doping agent. Further discussion on possible threshold limits and laboratory testing on different matrices (e.g. hair) to better clarify the origin of minimal amounts of clostebol in urines is advisable.

Biotransformation of anabolic androgenic steroids in human skin cells

In comparison to well-known drug-metabolizing organs such as the liver, the metabolic capacity of human skin is still not well elucidated despite the widespread use of topical drug application. To gain a comprehensive insight into anabolic steroid metabolism in the skin, six structurally related anabolic androgenic steroids, testosterone, metandienone, methyltestosterone, clostebol, dehydrochloromethyltestosterone, and methylclostebol, were applied to human keratinocytes and fibroblasts derived from the juvenile foreskin. Phase I metabolites obtained from incubation media were analyzed by gas chromatography-mass spectrometry. The 5α-reductase activity was predominant in the metabolic pathways as supported by the detection of 5α-reduced metabolites after incubation of testosterone, methyltestosterone, clostebol, and methylclostebol. Additionally, the stereochemistry structures of fully reduced metabolites (4α,5α-isomers) of clostebol and methylclostebol were newly confirmed in this study by the help of inhouse synthesized reference materials. The results provide insights into the steroid metabolism in human skin cells with respect to the characteristics of the chemical structures.

Annual banned-substance review-Analytical approaches in human sports drug testing 2021/2022

Also in 2021/2022, considerable efforts were invested into advancing human sports drug testing programs, recognizing and taking into account existing as well as emerging challenges in anti-doping, especially with regard to substances and methods of doping specified in the World Anti-Doping Agency's 2022 Prohibited List. In this edition of the annual banned-substance review, literature on recent developments published between October 2021 and September 2022 is summarized and discussed. Focus is put particularly on enhanced analytical approaches and complementary testing options in human doping controls, appreciating the exigence and mission in anti-doping and, equally, the contemporary "new normal" considering, for example, the athlete's exposome versus analytical sensitivity and applicable anti-doping regulations for result interpretation and management.