Leonardo’s Letter Debunks Theory Parkinson’s Is Caused by Pollution

<i> Stein is a science writer for United Press International</i>

Leonardo da Vinci apparently described Parkinson’s disease in his writings, debunking the theory that the brain disease is caused by pollution created by the Industrial Revolution, researchers said Wednesday.

“This is the best (evidence) that establishes the situation quite firmly,” said Dr. Donald Calne, a neurologist at the University of British Columbia in Vancouver, Canada.

“In my view this does establish beyond doubt that Parkinson’s disease existed in the 15th Century,” Calne said in a telephone interview.

About 1 million Americans suffer from Parkinson’s disease, which causes a progressive, devastating loss of muscle control characterized by distinctive tremors and other body movements.


Dr. James Parkinson, a British surgeon, named the disease and described it for the first time in 1817. Since that is when the Industrial Revolution was occurring in England, researchers suspected the disease may not have existed before then and that a pollutant produced by modern industry was to blame.

But Calne and two colleagues report in a letter in the New England Journal of Medicine that they found a passage in a letter that the famed Italian artist and scientist wrote between 1490 and 1500 in which Leonardo appears to describe patients with the Parkinson’s symptoms.

Leonardo “was interested in many aspects of movement, including physiology, and described an example of movement independent of consciousness,” Calne and his colleagues wrote.

In the letter, Leonardo described movements that “appear clearly in paralytics . . . who move their trembling limbs such as the head or the hands without permission of the soul; which soul with all its power cannot prevent these limbs from trembling.”


“The combination of difficulty with voluntary movement . . . and tremor can leave little doubt of the diagnosis,” Calne and his colleagues said. “Parkinson’s disease must surely have existed before the Industrial Revolution.”

The disease may not have been as common until Parkinson’s time because most people did not live long enough to develop symptoms, the researchers speculated.

Working with Dr. Adriana Dubini of Milan, Italy, and Dr. Gerald Stern of the University College School of Medicine in London, Calne found the Leonardo letter among manuscripts stored in Windsor Castle in England, Calne said.

Calne said in the telephone interview that discovery of the reference by Leonardo does not rule out the possibility that some substance that occurs naturally in the environment may play a role in the disease.


Dr. Abraham Lieberman, chairman of the medical advisory board of the American Parkinson’s Disease Assn., said Calne is a highly respected researcher. “Anything that Dr. Calne said I would certainly pay attention to. He’s very careful and very accurate,” Lieberman said by telephone.