There are few more emotive words in sport than drugs.

If anyone thinks it’s something that gets lost in the midst of time it is never too late for drugs allegations to be made as 1980 Olympic 100m gold medallist Alan Wells was implicated in a BBC Panorama investigation over the weekend.

Or, as Mo Farah found out, you can be implicated by association, with the same TV programme having questioned the methods of his coach Alberto Salazar’s training camp in the Oregon.

It left Farah, who left Twickenham a few years ago because he felt crossing the Atlantic would help his medals quest, pulling out of a Diamond League meeting because he was drained and pledging to seek “urgent answers” from Salazar.

However, by refusing to dispense with the services of the man at the centre of allegations, there were plenty lining up to question the integrity of Britain’s most decorated athlete.

Having spent years sneering at the likes of Justin Gatlin, whose exploits in setting the 100m world alight this year seem rather tainted by his previous multiple doping offences, the Panorama programme brought the whole issue rather uncomfortably close to home.

Riding out of the other side, rather appropriately, at the weekend came Frankie Dettori – a hugely popular winner of the Epsom Derby on Golden Horn.

Of course, this was Dettori’s first appearance in the event since a six-month drug ban for cocaine abuse.

The loveable Italian’s use of the drug is considered recreational rather than performance-enhancing, but the fact remains he took banned substances.

The investigators do a great service in exposing the cheats, but there are never any winners because in a sporting sense drugs really are a disease. They not only affect the people who use them, they blur the lines in the very sports they represent.

Put simply, we just don’t know who to believe any more.