Contador's urine sample, taken during the day before his clenbuterol positive sample, was reported to contain plastic residue (plasticizers) indicating possible blood doping as these materials are introduced to the bloodstream from blood bags used in blood doping,[158] but the test was not recognised by the World Anti-Doping Agency, so https://griffinsbjrr.webbuzzfeed.com/17388454/sobre-arka-online-contabilidade