Valco Instruments Co. Inc


Valco Instruments Co. Inc.pubs.acs.org/doi/pdf/10.1021/ac00209a725terol levels, and lead to an intense ag- gressive beha...

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emerged at the 1984 Los Angeles Olympics (boycotted by many of the then Eastern bloc nations). Athletes withdrew about two units of blood several days prior to the Olympics and then reinjected the blood before competing. Blood doping, as this process is called, raises oxygen-carrying capacity by about 10% and thus increases endurance. It also carries the risk of promoting circulatory failure. Indeed, all of these drugs and schemes pose severe health risks. Steroid use, for instance, can stop bone growth, cause liver dysfunction and possibly liver cancer, affect the endocrine system, trigger breast enlargement in males, adversely affect cholesterol levels, and lead to an intense aggressive behavior known as steroid rage. Unlike marijuana or cocaine, these are not substances with "pleasurable" effects. To keep one step ahead of substance abusers, organizations such as the International Olympic Committee now ban entire classes of drugs rather than specific compounds. The testing procedure, according to Sample, begins with an observed, on-site urine collection from top-finishing athletes following an event. Random screening also takes place. Refusing to be tested is considered the same as testing positive. Half of the sample is sent for testing, and the rest is stored in case an athlete contests the analysis results. A contesting athlete does have the right to observe each step of the analysis. Currently five procedures screen for potential violations. Procedural details vary, depending on where the analyses are performed. Procedure 1 picks up certain stimulants that are excreted unchanged. Basically, procedure 1 is an alkaline ether extract followed by GC with GC/MS confirmation. Drugs such as narcotics, beta blockers, and some stimulants, which are metabolized and excreted as conjugates, are captured in procedure 2. In this screen, the analyte is first hydrolyzed. This is followed by an alkaline ether extraction and derivatization with a standard agent such as trifluoroacetic acid. The material is then detected by GC with a nitrogen-phosphorus detector or by GC/MS with full-cycle or selective ion monitoring. According to Sample, recent results from athletic events suggest that abuse of narcotics or beta blockers among amateur athletes is not very common. Procedures 3 and 5 are alkaline and acidic extractions, respectively, to detect caffeine and diuretics. The alkaline extract is screened by HPLC, whereas the procedure 5 material is analyzed by GC/MS.

Stimulants such as caffeine pose a problem of what constitutes misuse. For instance, the cutoff for caffeine has been set at 12 /ig/mL, which, claims Sample, corresponds to downing 10-15 cups of coffee in 15 min. Analysts also have to account for stimulants such as ephedrine that are present in over-thecounter cold remedies. Although stimulants have lost some of their nineteenth century popularity, they still turn up in about 20% of sports drug misuse cases. On the other hand, steroid use has grown during the last decade; today, experts believe steroids are probably the most misused chemical. At Seoul, steroids accounted for nearly 60% of the positive tests. The most commonly misused steroid is nandrolone, which can be detected for up to one year after use. (Ben Johnson, who lost the gold medal in the 100-m run because of alleged steroid use, tested positive for stanozolol, a synthetic derivative of testosterone.) Procedure 4 screens anabolic steroids. In fact, this is a two-part procedure. Steroids that are excreted unconjugated are extracted from urine and derivatized for analysis by GC/MS with selective ion monitoring. Steroids that are excreted metabolized are extracted on a C-18 or ion-exchange column, hydrolyzed by an enzyme, extracted at pH 9, derivatized, and then analyzed by GC/MS. Testosterone misuse is identified by measuring its ratio with another naturally occurring hormone, epitestosterone. This second hormone is neither a metabolite nor a precursor of testosterone and thus will not be affected by changes in testosterone levels. A ratio of testosterone to epitestosterone greater than six indicates misuse, although analysts must worry about individuals with genetically determined low levels of epitestosterone. Blood doping presents a greater problem for analysts. It is possible to detect additional blood by testing for the protein hormone erythropoietin. This protein triggers hemoglobin production, and thus synthesis of erythropoietin would be suppressed in an individual with excess blood. However, the analysis procedure is invasive—it requires a blood sample—and not very sensitive. At present, officials must rely on self-reporting to identify athletes involved in this practice. Overall, however, drug testing has made it more difficult for athletes to misuse drugs. Unfortunately, says Sample, "There doesn't seem to be any end to the drugs athletes are able to abuse." Alan R. Newman

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ANALYTICAL CHEMISTRY, VOL. 62, NO. 10, MAY 15, 1990 · 603 A