An Italian judge is investigating the suspicious death of 70 football stars amid fears that drugs their clubs gave them may have triggered their fatal illnesses.

Raffeale Guariniello, a magistrate in Turin, is investigating the unusually high incidence of cancer and motor neurone disease amongst players who've appeared for Italy's top clubs.

Gianluca Signorini, a defender with Roma and Genoa through the nineties, is the latest player to die - aged just 42.

Gianluca Signorini - died aged 42

It's claimed that the use of performance enhancing hormones and pain-killing injections along with intensive training are causing the high mortality rate.

Now, football associations around Europe are beginning their own investigations - which could lead to multi million dollar legal claims.

Sandro Donati is the head of doping investigations at the Italian Olympic Committee. He explained how hard it would be to prove a link for certain.

"We must be very careful because it is a complicated problem" he said.

"There is the possibility of this problem being caused by drugs used to enhance sporting performances but we must also look at other hypotheses.

"We must also consider the effects of the violent impact on the brain caused by heading the ball.

"Guariniello is the first independent voice to reflect on this problem, but something should have been done sooner" he said.

Jaap Stam tested positive for Nandrolone

Donati questioned whether the ethics of sport could be part of the problem.

"At this moment sports institutions only care about having a high level of competition, and it's the same in the media" he said.

"They only care about who is the champion, and never look at the big problems under the surface.

"Society in general must reflect, after a 100 years of professional sport, what is its purpose? Is it to increase people's health or destroy it?

"For eleven years I was the national athletics coach and I collaborated with many different Italian national teams, but when I began to speak about doping the sports world turned its back on me" he went on.

"The sports world doesn't need me, it needs a global solution, but it's a signal that the sports world doesn't want to acknowledge the problem. For normal people sport is meant to make you healthier, but now people only care about who is the winner".

You can hear all of Alan Green's interview with Sandro Donati on World Football on Saturday 25 January. Use the audio link on the front page.