Arsenic Is Linked to British King’s Episodes of Madness

The well-known madness of King George III, who ruled England during the American Revolution, was probably exacerbated by arsenic-contaminated medicines used to treat some of his symptoms, a study of his hair in today’s issue of the journal Lancet found.

In 1966, researchers proposed that George III suffered from a genetic disorder called variegate porphyria, an overproduction of the reddish pigments in hemoglobin, which carry oxygen in red blood cells. George III displayed many symptoms of porphyria, including abdominal pain, reddish urine and mental disturbance. Similar symptoms have been reported across several generations of the royal lineage.

Arsenic disrupts hemoglobin production, but that disruption paradoxically triggers many of porphyria’s symptoms.

Biochemist Martin J. Warren of the University of Kent and his colleagues studied five strands of George III’s gray hair preserved at London’s Science Museum. They concluded that the hair had an arsenic content of 17 parts per million -- 17 times the level generally considered to indicate arsenic poisoning.

“It is extremely likely that his bouts of madness were due to severe porphyric attacks,” Warren said. “Arsenic may have precipitated his attacks, or made them much more severe.”

George III’s nearly 60-year rule began in 1760. During his reign, he experienced at least five bouts of extreme derangement, each lasting weeks.

He occasionally became violent, and he often talked to imaginary people, including a tree he thought was the Prussian king, Frederick II.