ESSENDON coach Mark Thompson insists his players aren't facing health risks over the club's 2012 supplements program, despite revelations the AFL was monitoring them over fears of cancer and hormonal problems.

Thompson said on Friday the Essendon players had been extensively briefed by club officials regarding the supplements given to them.

"I think it's OK. The players have been communicated to by specialists and the drugs, the supplements that we have given the players, they know that they're not harmful," Thompson told reporters.

"There's no risk. One actually helps in part of the treatment for cancer.

"So we haven't got a problem there at all as far as our communication and our players' awareness of what's healthy and what's not."

The league had arranged for special testing of samples from Essendon players during 2012, months before the club's supplements scandal broke.

Video evidence emerged this week of a speech from AFL medical officer Peter Harcourt last November at an anti-doping conference.

Harcourt told the conference in Zurich about the overseas testing and said he was setting up a program to monitor the players involved in the supplements regime because of fears they might contract cancer or have other hormonal problems.

Essendon chairman Paul Little has called for the AFL to consider a sanction for Harcourt and to establish whether the doctor had broken league rules.

Thompson described Harcourt's speech as damaging.

"I'm in line with the club. It's pretty poor, a poor reflection," Thompson said.

"The club, they've already said publicly that they would like (an explanation).

"To me it's already done.

"An apology, what does that mean? Nothing.

"The damage has been done already."

The AFL Players' Association has slammed Harcourt for suggesting there was a passive acceptance by the players of the club's supplements program.

Asked if the players were insulted, Thompson said: "You'd think they would be. But I can't answer for them."