Symptoms of arsenic poisoning can take eight to 14 years to manifest in a person.

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Other senior ministers have suggested that the arsenic poisoning may have been self-inflicted.

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But subsequent medical tests cleared him of any acute or chronic arsenic poisoning.

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When we think of the problems that plague the globe, arsenic poisoning is not one that springs readily to mind.

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Apart from disfiguring the skin, after two decades arsenic poisoning has a high risk of causing fatal cancer in the lungs, liver, bladder and kidneys.

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Cynthia was accused of poisoning him with arsenic.

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The Swiss team say the presence of arsenic in Napoleon's hair, the source of the poisoning theory, was linked to this enthusiasm for wine.

BBC: RELATED BBC SITES

Some well water contains so much arsenic that an adult drinking four litres a day could start to show signs of poisoning.

BBC: By Helen Sewell of BBC Science