Biological functions of cobalt and its toxicology and detection in anti-doping control

Objectives. Over the last decade, hematopoietic stimulants have grown increasingly popular in elite sports. This is supported by the growing number of high-profile doping scandals linked to their use. A group of these stimulants includes cobalt salts, which cause an increase in the oxygen capacity of the blood as well as a powerful stimulation of metabolic processes, resulting innoticeable competitive advantages. The use of cobalt salts is regulated according to the Prohibited List of the World Anti-Doping Agency (WADA). Currently, only a few works have been dedicated to solving the problem of detecting the abuse of cobalt salts in anti-doping control. Only a few laboratories have included cobalt salt determination in their methodological bases. The purpose of this review is to attract the attention of the scientific community to the toxicity of cobalt compounds, consequences of their intake, and pharmacokinetics, as well as the problems in their detection methods due to their widespread availability in the modern market and the growing number of abuse cases.
Results. The main biological functions of cobalt, cellular levels of exposure, toxicity, and symptoms of cobalt salt poisoning are presented in detail in this review article. The data from the literature on the main methods for detecting cobalt as a doping agent have been generalized and systematized. There is a major focus on the amount of cobalt in dietary supplements that could cause an athlete to test positive for cobalt when they are consumed.
Conclusions. After analyzing promising cobalt detection approaches and methods, it was determined that high-performance liquid chromatography in combination with inductively coupled plasma mass spectrometry has an undeniable advantage for detecting cobalt as a doping agent. The lack of explicit WADA requirements for detection methods and the lack of its obligation to determine cobalt make it tempting for unscrupulous athletes to use its salts. Therefore, antidoping laboratories must implement the abovementioned method as soon as possible.

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