Real life James Bond? This Russian spy autopsy is "most dangerous ever".

The autopsy on the body of poisoned former Russian spy Alexander Litvinenko has been described as one of the most dangerous ever undertaken, on day two of an inquiry into his death.

Mr Litvinenko died in a London hospital on November 23, 2006, three weeks after drinking tea infused with deadly polonium-210 at a luxury hotel in the city’s Mayfair district.

The London inquiry was told “an inspired hunch” by police led them to bring in atomic scientists, who found Mr Litvinenko tested positive for alpha radiation poisoning two days before he died.

Lead pathologist Nathaniel Cary said without that finding, the cause of death would not have been discovered in a post-mortem.

He added he was unaware of any other case of someone being poisoned with alpha radiation in Britain, and probably the world.

“It has been described as the most dangerous post-mortem examination ever undertaken in the Western world and I think that is probably right,” he told the inquiry.

Those involved had needed to wear two white protective suits with specialised hoods fed with filtered air.

Hours after drinking the tea, Mr Litvinenko suffered from sickness and stomach pains.

He later lost all his hair and died 22 days after the meeting from a cardiac arrest caused by organ malfunction.

Dr Cary said the polonium-210 was the “smoking gun in the case – it shows you what happened”.

One of Britain’s top nuclear scientists, identified only as A1, told the inquiry only a tiny amount, nanograms to micrograms, of polonium would be fatal.

Tests had shown traces of polonium in parts of a ceramic teapot from the Millennium Hotel, including its spout, which were “off the scale”, she said.

She added that it was impossible to know where the substance, which must be produced in a nuclear reactor, had come from.

The expert estimated that 100 grams of polonium-210 were produced globally each year, the vast majority in Russia.

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Suspect dismisses inquiry evidence as ‘nonsense’

British police have named two chief suspects they want to question in connection with Mr Litvinenko’s death – Andrei Lugovoi and Dmitri Kovtun – but Russia refuses to extradite them.

Mr Lugovoi, now an MP in the Russian Duma, said any evidence produced against him at the inquiry was a falsification and nonsense.

In a letter dictated from his deathbed, Mr Litvinenko accused Russian president Vladimir Putin of having ordered his murder, an accusation which the Kremlin denies.

Mr Litvinenko served in the KGB during Soviet times and then in its successor agency, the FSB, when Mr Putin led it before becoming president in 2000.

In 1998, he and other FSB agents gave a press conference in Moscow accusing the agency of a plot to kill exiled oligarch Boris Berezovsky, who helped bring Mr Putin to power but later turned against him.

Mr Litvinenko was tried for abuse of power and, although acquitted in 1999, he fled Russia and was granted asylum in Britain.

The British government long opposed the public inquiry but agreed last year amid worsening relations with Moscow.

The inquiry is expected to last two months.

This article was original published on ABC and has been republished here with full permission.