Total ban on pesticides unrealistic: researcher
Special to The Compass
A leading Canadian researcher says while cosmetic use of chemical pesticides should be banned, a total ban on such products is unrealistic.
“Some farmers depend on them for their livelihood and without them their crop yields would be low...and in some poorer countries, without pesticides, people would be dying of malaria,” says Dr. Shawn Hayley who is studying the link between environmental toxins and Parkinson’s Disease.
In terms of the farming indus- try, Dr. Hayley says looking at more organically friendly products should be the way of the future.
“But just to have a pretty lawn, I’d ban all chemical pesticides.”
No one knows what causes Parkinson’s Disease. However, Dr. Hayley and other researchers across the country are trying to find answers to that question.
Dr. Hayley is originally from St. John’s and is a Memorial University graduate.
He now works as associate professor and Canada Research Chair of Behavioural Neuroscience at Carleton University in Ottawa.
A neurodegenerative disease, Parkinson’s affects over 100,000 Canadians.
Movement is normally controlled by dopamine, a chemical that carries signals between the nerves in the brain. When cells that normally produce dopamine die, the symptoms of Parkinson’s appear.
Often touted as the disease where “your body turns against you,” many people with Parkinson’s suffer from tremors, slowness and stiffness, balance problems, and rigidity of the muscles. Other symptoms include fatigue, soft speech, writing problems, stooped posture, and depression.
Dr. Hayley believes that environmental toxins such as chemicals in some pesticides, insecticides and fungicides as well as heavy metals including aluminum, lead, iron, mercury, manganese and methyl mercury may lead to an increased incidence of Parkinson’s.
“I’ve started to study the herbicide Paraquat here in my lab,” Dr. Hayley says of the herbicide that’s used in many parts of the world, including Canada.
Dr. Hayley’s research has found that, administering Paraquat to rodents destroys about 30 per cent of the dopamine neurons in the brain.
“These are the same neurons that die in Parkinson’s and these animals then show some slowness of movement similar to Parkinson’s patients,” Dr. Hayley says.
Dr. Hayley’s research is now looking at ways the herbicides could be killing these dopamine neurons.
“We’re gathering evidence that activation of the inflammatory immune system seems to be one important player in this pathology,” he says.
In particular, Dr. Hayley says, Paraquat causes an activation of specialized brain cells called microglial cells.
These cells are important in fighting off infection, he says.
However, he says, Paraquat recognizes these microglial cells as foreign cells, which causes the cells to be over-activated for long periods of time.
“This is causing damage to oth- erwise healthy neurons so those same defenses that are used to fight off infections are killing healthy neurons,” he says.
Dr. Hayley’s research explores why such damage is taking place.
“It’s probably not just one toxin that’s responsible for such a complex disease as Parkinson’s. It’s probably a combination of multiple toxins over one’s lifetime,” he says.
As well, Dr. Hayley says, there are likely genetic factors that come into play in persons with Parkinson’s.
Dr. Hayley is one of hundreds of Canadian researchers who have received funding from the Parkinson Society of Canada.
His hope is that the research will lead to drugs that could help slow the progression of the disease.
“Right now we’re simply managing the symptoms,” Dr. Hayley says.
Dr. Hayley will hold a public lecture at the Health Sciences Centre in St. John’s on Thurs- day, June 11 where he’ll discuss his research linking environmental factors to Parkinson’s disease.
The Parkinson Society Newfoundland and Labrador is hosting the lecture.
“This is exciting for us because unlike many diseases, researchers have yet to determine a cause for Parkinson’s. To have researchers focus on the environment gives us hope that perhaps a cause will be found,” says Patricia Morrissey, executive director of the provincial Parkinson Society.
The society will video-conference Dr. Hayley’s lecture to Carbonear, Corner Brook, Grand Falls-Windsor, Gander, Clarenville and Burin.
For more information on Dr. Hayley’s presentation call 709754-4428, toll free at 1-800-5677020 or by e-mail email@example.com
Dr. Shawn Hayley works as associate professor and Canada Research Chair of Behavioural Neuroscience at Carleton University in Ottawa.