What chemical element was said to have led to the death of Napoleon?

Napoleon Bonaparte died in 1821, but the cause of his demise is still being debated. At one time, a group of French doctors and pathologists were said to have confirmed that Napoleon I died of arsenic poisoning during his imprisonment on the island of St. Helena. This conclusion was made after analysis of the Emperor's hair strands at death. Analysis showed that the amount of arsenic in Napoleon's hair has been exceeded 38 times compared with the yield that can withstand the human body.

A 2008 analysis suggests high levels of arsenic in Napoleon Bonaparte's hair throughout his life, suggesting he was not poisoned at the end of his life while in exile on the island of Saint Helena, rather he probably absorbed arsenic constantly throughout his life. Physicists at the University of Milano-Bicocca and the University of Pavia compared the arsenic levels in hair samples taken from Napoleon Bonaparte at various stages in his life with levels in hairs from Napoleon's son (the King of Rome), Empress Josephine and 10 living persons. The results showed that the level of arsenic in the hair samples from 200 years ago was found to be 100 times greater than the average level detected in samples from persons living today. According to the researchers, including toxicologists who participated in the study, it is evident that this was not a case of poisoning but instead the result of the constant absorption of arsenic.