A woman in Canada has died after the pills she bought online turned out to contain radioactive material. Marcia Bergeron, 57, chose to buy her anti-anxiety medicine over the internet instead of through a doctor.

But the pills turned out to contain high concentrations of strontium, selenium, aluminium, barium and even more alarmingly uranium - the radioactive element enriched for use in nuclear power stations.

When she began to take her pills, Bergeron started to experience blurred vision, but even when her hair started to fall out she didn't stop taking the internet pills. A week after experiencing her first symptom, she was found dead in her home.

"This is a tragic reminder that you should always consult a doctor and never purchase pills online or reply to emails that offer miracle cures at knock-down prices," said Graham Cluley, at online security company Sophos.

Radioactive medication

"Self-prescription can not only result in you buying medication that you don't need, but more worryingly there's no guarantee that the pills won't be just a cheap concoction of whatever minerals the sellers can get their hands on, designed for the sole purpose of earning money.

"It's madness to buy drugs from an unknown source. Who knows what's in it?"

The Canadian Pharmacists' Association has said that as much as 50 per cent of the drugs from online pharmacies can be sub-standard.

"We do not know how many other Canadians could be buying counterfeit medications through the internet," said local Liberal MP Dr Carolyn Bennett.

"It is time for the government to act to ensure Canadians are protected."