Summer Olympic Games federal government; the country's economic crisis; health and safety concerns surrounding the Zika virus and significant pollution in the Guanabara Bay; and a state-sponsored doping scandal involving Russia, which affected the participation of its athletes in the Games. Tokyo, Japan will host the 2020 Summer Olympics, making it the first Asian city to host the Olympic Games twice. Forty-two sports, spanning 55 disciplines, have been part of the Olympic program at one point or another. Twenty-eight sports have comprised the schedule for three of the recent games, 2000, 2004, and 2008 Summer Olympics. Due to the removal of baseball and
Olympic Games detect banned substances. Several athletes were barred from competition by their National Olympic Committees prior to the Games; only three athletes failed drug tests while in competition in Beijing. In London over 6,000 Olympic and Paralympic athletes were tested. Prior to the Games 107 athletes tested positive for banned substances and were not allowed to compete. During and after the Games eight athletes tested positive for a banned substance and were suspended, including shot putter Nadzeya Ostapchuk, who was stripped of her gold medal. Russia was partially banned from the 2016 Summer Olympics and completely banned from the 2018 Winter