Ioanna AthanasiadouIoanna Athanasiadou is currently working on her PhD in Pharmacokinetics/pharmacodynamics at the Faculty of Pharmacy, University of Athens. Athanasiadou has worked for more than five years as a Lab Scientist at Antidoping Control Laboratory of Athens (Greece) dealing with the analysis of routine doping control samples.  

The upcoming Sochi Olympic Games will see 57 percent more doping tests than the previous Winter Olympics in Vancouver, and the tests will be the toughest ever, the head of the International Olympic Committee (IOC) has announced.

Doping is a multifaceted phenomenon, officially defined as the occurrence of one or more of the anti-doping rule violations as stated in the World Anti-Doping Code: the presence of a prohibited substance (or its metabolites), the misuse or attempted use or possession or trafficking of a prohibited substance or method, the refusal or failure for testing, the (attempted) administration to any athlete of any prohibited method or substance and tampering or any attempt to tamper collected samples are all considered as doping offences.

shutterstock_172412651Prohibited pharmaceutical substances and methods are listed under different classes in the prohibited list of the World Anti-Doping Agency (WADA), including dope masking (Class S5) and manipulation (Class M2). Masking agents are not characterized as performance-enhancing drugs, and their objective is to mask the presence of other doping agents. This category includes diuretics, epitestosterone, probenecid, 5a-reductase inhibitors, and plasma volume expanders, which are all forbidden in both in-and-out of competition doping control testing.

Masking strategies have the potential to inhibit the passive excretion of doping agents by altering the urinary pH, which conceals their presence by increasing the urine volume or alters hematological parameters. For example, frequent use of diuretics are being used quite often by athletes causing a rapid urine production and loss of electrolytes, resulting in diluted concentrations of abused substances that may otherwise not be undetected.

Alterations on body hydration such as dehydration caused by diuretics could also be used as masking techniques. Recently, it has been noticed that over drinking before anti-doping sample collection is being adopted by some athletes as masking procedure, since dilution is not prohibited as a practice. For instance, recombinant human erythropoietin (rHuEPO)—one of the urine profiles run to detect doping—has been reported as undetectable in some cases, which could be attributed to highly diluted urine samples.

Based on these observations, a simulation analysis was conducted examining the influence of hyperhydration on the urine pharmacokinetic profiles of rHuEPO and its possible role as a masking procedure. The results revealed a clear effect of hyperhydration on the rHuEPO urine profile, supporting the reported cases of undetectable erythropoietin urine levels. These findings may have practical implications regarding the timing of urine collection during antidoping sampling and the subsequent detection of doping agents if hyperhydration could be used as masking.

Any method that can alter the integrity and validity of the specimens collected during the doping control sampling procedure is considered manipulation. Numerous cases have already been reported regarding attempts of doping manipulation, such as urine substitution and/or adulteration. For example, proteolytic enzymes are used by athletes in order to manipulate and thus mask the abuse of peptide hormones such as human chorionic gonadotropin (hCG), rHuEPO, and various kinds of insulin. Proteases can efficiently and rapidly degrade urinary proteins without affecting other parameters that could raise suspicion of manipulation. The introduction of minuscule amounts of proteases into the urethra by some elite athletes before the sampling procedure has been reported. Proteases and protease cocktails are readily available in various household products, with major applications as detergent enzymes and nutritional supplements. Furthermore, cases have been reported where a non-alcoholic beer was provided as a urine sample or specimens collected by different individuals were proven to be identical.

Despite the strict regulations and resulting sanctions, anti-doping authorities (including laboratories and national/international organizations) are involved in the continuous challenge of preserving the values of fair competition and clean sports.