Commonwealth Games Federation chief Michael Fennell said on Tuesday that the two positive doping tests of the Nigerian athletes could be related to use of supplements.
Nigerian sprinter Samuel Okon tested positive for a banned stimulant to cause further embarrassment for the African nation at the 2010 Commonwealth Games in Delhi.
Okon, who finished sixth in the 110 meters hurdles, tested positive for the banned stimulant methylhexaneamine the same as compatriot and women's 100 meters winner Damola Osayomi.
"The same substance is coming up but at this stage I cannot speak definitely about where it is coming from. But at this stage it appears to us it maybe coming from the use of supplements.
"The supplement industry is by and large an unregulated industry worldwide and it is an industry that is causing great concern not only for the fight against doping but also the protection of the athletes and outside of sports for the protection of people," Fennell said.
He also added that Okon may not be asking to get his B sample tested.
"As far as the second athlete is concerned, we have heard that he is waving the right to have his B sample test but this has not been confirmed yet. We have to ensure all of these things are confirmed by the athlete when we have the provisional hearing later today," Fennell added.
Meanwhile, Delhi Games Organising Committee chairman Suresh Kalmadi reiterated that he still harbours the dream of hosting an Olympics Games in the country.
"I have a dream of hosting the Olympics but I don't know when," Kalmadi said.
"I will have to talk to the government and the members of the Indian Olympic Association and then I can decide when we can do it. But this is only possible after the Commonwealth Games are over," he added.
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