A second Nigerian has failed a drugs test at the Commonwealth Games.

Samuel Okon, 24, who was sixth in the 110m hurdles won by Andy Turner, tested positive for the same drug as women’s 100m winner Damola Osayemi.

According to Commonwealth Games Federation president Mike Fennell, Okon is waiving the right to the B sample test but this has yet to be confirmed.

Osayemi has been provisionally suspended until the result of her B sample is received.

Both athletes tested positive for methylhexaneamine, which is a stimulant that was added in 2009 to the World Anti-Doping Agency’s list of banned drugs. It was reclassified earlier this year, meaning it can be used with a therapeutic use exception certificate.

Fennell said: “We are concerned with the number of incidents that are coming up with the same substance.

“At this stage I cannot speak very definitively as to where it’s coming from but it appears that it may be coming from the use of supplements.

“The supplements industry is by and large an unregulated industry worldwide and it is an industry that is a cause of great concern, not only for the fight against doping but also the protection of athletes.”

Asked when the results for Okon’s B sample test would be known, Fennell replied: “We have been informed that the athlete is waiving the right to the B sample (test) but this has yet to be confirmed.

“We will confirm this at his hearing this afternoon.”

The Nigerian team have been informed and are also investigating.

“We have already had discussions with the leadership of the Nigerian team, who are themselves taking it very seriously. They are very concerned about it,” Fennell told a news conference.