John Henry (toxicologist)
Learn more about John Henry (toxicologist)
John Henry is a professor specializing in toxicology in the Faculty of Medicine, Imperial College London, at St Mary's Hospital in Paddington. He has done research on the health effects of cannabis, cocaine and other recreational drugs.
He was the clinical toxicologist who dealt with the poisoning case of Russian dissident Alexander Litvinenko (at University College Hospital) in November 2006. Initially he suggested poisoning from the metal thallium, although it later turned out that the toxin was polonium-210.