Do rumours that the English poisoned him carry any weight?
None at all; since this is an old chestnut that regularly recurs, I will take the liberty of reposting what I have said about the matter previously:
Discussion of history of the question: Arsenic: environmental chemistry, health threats and waste treatment - Kevin R. Henke - Google Books
It is by no means certain that the arsenic found in the Emperor's corpse was abnormally high, and many of the usual signs of arsenic poisoning were absent:
"The postmortem examination was performed the day after Napoleon's death (6 May 1821) by Dr Antommarchi, a pupil of Giuseppe Mascagni (1755-1815), a famous anatomy professor at the University of Siena.[1,2]
According to Antommarchi's first and second autopsy reports, as well as the findings described by the English physicians,[1-3]
the external inspection documented an important amount of weight loss. Napoleon's height was 168 cm and his skin extremely pale. His hands and feet had no pathologic alterations. Internal examinations revealed several 'tuberculous' excavations in the superior lobe of the left lung; the right lung was completely normal. Several bronchial and mediastinal lymph nodes were enlarged and necrotic. In addition, a moderate, bilateral pleural effusion was observed. The heart was very pale, but without pathologic findings.
The stomach was filled with dark material that resembled coffee grounds, a strong indication of upper gastrointestinal bleeding that could have been the immediate cause of death. Examination of the gastric wall revealed an ulcerated lesion with hardened, irregular borders that extended from the cardia to the pyloric region (>10 cm) and a smaller prepyloric ulcer with thick adherences to the liver. The lesser omentum was enlarged and hardened, in contrast to a normal greater omentum. The perigastric lymph nodes were hardened and enlarged and some of them were necrotic. The liver and the spleen were congested. Dark material that resembled coffee grounds was also found in the colon.
The kidneys and the urinary bladder showed no relevant pathologic findings. Other relevant negative findings included the absence of hyperkeratotic lesions in the skin of the hands and feet, normal nails, the absence of other tumors, and "a very pale heart without any hemorrhage".
In aggregate, these findings militate against the possibility of chronic arsenic poisoning, which is characterized by palmar and solar keratosis, Mee's lines in the fingernails and toenails, cancers of the skin, lung and bladder,
and subendocardial hemorrhage on the left ventricular wall of the interventricular septum.
According to Maresch, the absence of subendocardial hemorrhage virtually rules out arsenic poisoning as a cause of death.
In 2004 it was shown that an elevated arsenic concentration was found in Napoleon's hair in 1814, before his exile to St Helena.
Other than deliberate poisoning, several possible sources of arsenic intoxication have been proposed in Napoleon's case.
In addition, historical evidence suggests that this theory of arsenic poisoning is highly unlikely.
Together, these arguments suggest arsenic poisoning should be excluded as the cause of Napoleon's death."
(From this article: Medscape: Medscape Access
From another article:
"The characteristic clinical symptoms of chronic arsenic poisoning were absent, symptoms such as extreme weight loss, loss of nails, fatty degeneration of the liver (steatosis), skin pigmentation, patchy bleeding visible as dark red spots on the inner surface of the stomach, Mees' lines and neurological symptoms. Furthermore, prolonged administration of arsenic leads to renal failure and anuria (that is, failure to produce urine). None of this was reported with respect to Napoleon and no physician, including those present at the autopsy, found any evidence of it. Also not reported was any evidence of vasodilatation (that is, reddening), a characteristic sign of the effects of arsenic on blood vessels. Other characteristic signs of chronic arsenic poisoning were considered absent at the autopsy, notably hyperkeratosis, that is, thickening of the scaly layer of the skin on the hands and feet. As to the general lack of body hair noted at the autopsy, it is true that this is characteristic feature of arsenic poisoning, but it could equally be explained by a hormonal syndrome diagnosed in Napoleon."
More here: http://www.napoleon.org/en/reading_r...ic_emperor.asp
On the arsenic levels, I would point again to the study from 2008: http://www.sciencedaily.com/releases...0211131357.htm Analysis of Napoleon’s Hair Deflates Arsenic Poisoning Theories - NYTimes.com
The results were published in a scientific paper in Il Nuovo Saggiatore, Bolletino de la Societa Italiana di Fisica, 2008: M. Clemenza et al., Misure con attivazione neutronica sulla presenza di arsenico nei capelli de Napoleone Buonaparte e di suoi familiari.
Another brief article worth looking at: http://www.clinchem.org/cgi/reprint/54/12/2092.pdf
The studies conducted at Pavia using the 'neutron activation' method did in fact produce most interesting results. They showed that the level of arsenic in Napoleon's hair was about 100 times the modern average, but that there had been no significant change in the level over the course of his life (they also had hair samples from his boyhood, and from his time in Elba), and moreover that the levels were much the same as those in his son and in the Empress Josephine, among others. This shows that he neither ingested any exceptional quantity of arsenic at Elba, nor died from its effects, but that the relatively high levels (by modern standards) must be ascribed to environmental factors. This was a rigorous scientific study undertaken at Italy's National Institute of Nuclear Physics using the most advanced techniques available, and published in a reputable journal, Il Nuovo Saggiatore. If the results cannot be shown to have been faulty, they must be accepted, I think, as fairly conclusive.
So, all in all, the best evidence suggests that it is most unlikely that Napoleon died of arsenic poisoning, and there is no reason to suppose that such arsenic as there was in his body was deliberately administered to him.