SPORTS cheats beware. As of 1 January, professional athletes became subject to routine checks on steroid concentrations in their urine. These tests won’t be used to spot specific drugs, but to form a baseline by which to detect any future suspicious deviations from the athlete’s normal physiology. The checks have been added to the World Anti-Doping Agency’s “biological passport”, a procedure for monitoring every athlete’s metabolic profile.

Since WADA introduced the passports in 2009, various components of athletes’ blood are tested about nine times a year. These include the mass of oxygen-carrying haemoglobin, and the number of red blood cells present in a sample, which can reveal a suspected blood transfusion or doping with the hormone erythropoietin, which enriches the oxygen content of blood. Now the same routine is being applied to steroids found in urine. To date, the only routine check on steroid misuse is through individual measurements of testosterone and epitestosterone. WADA says that the new steroid profile will monitor six steroids and the ratios between them to gauge any abnormal fluctuations from ratios normally present in urine. “We can’t put a number on how many people will be caught out, but a more intelligent anti-doping programme should deter athletes from cheating,” says Ben Nichols, a WADA spokesman. http://www.newscientist.com/article/mg22129502.400-athletes-biological-passports-will-track-steroid-use.html#.UsV1YfRDt8E