British 'cleared' of Napoleon's murder

Some theorists have insisted the French emperor's enemies had him poisoned on the isle of St Helena. They pointed to the high levels of arsenic discovered by modern testing methods in samples of the dead man's hair as proof of the conspiracy.

But now, new research suggests Napoleon's exposure to the toxic element was long term and unlikely to be the primary cause of his death.

Napoleon was exiled following defeat at the Battle of Waterloo in 1815. He died in May 1821, still in exile.

Official post-mortem reports at the time indicated cancer arising from a perforated stomach ulcer had claimed him.

Before and after

The chief suspect in the arsenic murder theory was one of Napoleon's companions, Count Charles de Montholon.

It was he, some have alleged, who poisoned the emperor on the instructions of the British. London wanted to rid Europe of Napoleon's continuing influence.

But a new analysis of Napoleon's hairs taken in 1805, 1814 - prior to his exile - and 1821 cast doubt on the theory.

All the samples, tested at the police toxicology lab in Paris, France, show high levels of arsenic - between 15 to 100 parts per million.

This would suggest that, if arsenic was indeed the cause of Napoleon's death, he had been exposed to it at various times during his later life - not just on St Helena.

Ivan Ricordel, who led the researchers, told AFP: "If arsenic caused Napoleon's death, he would have died three times over."

Because of the way that arsenic is absorbed by the growing hair, it is impossible to pinpoint when Napoleon came into contact with the poison.

Wallpaper theory

The maximum safe limit is widely considered to be only three parts per million.

The results were published in a French magazine, Science et Vie, which declared that this proved that there had been no poisoning at St Helena.

However, it is still unclear how Napoleon came to be exposed to such a high level of arsenic throughout his later life.

Possibilities include arsenic used to produce a green colour in wallpaper, handling gun cartridges, or even 19th Century hair restorer, which was known to contain arsenic.

After his death, Napoleon's body was brought back to Paris and interred at the Invalides.

Calls for its exhumation to solve the mystery have so far been resisted by the authorities.