Ask the expert: Can environmental factors cause Parkinson’s?
Author: Saskia MairPublished: 11 June 2020
Prep: Cook: Serves:
In the latest in our ‘Ask the expert’ series, neurologist Dr Ray Dorsey discusses how “the rise of Parkinson’s may be largely human-made”, the risk of certain pesticides – and why he thinks activism is crucial to changing the course of the condition
How are environmental factors linked to Parkinson’s?
The rise of Parkinson’s may be largely human-made. The condition is tied to several environmental factors, including certain pesticides, industrial solvents, heavy metals, and air pollution. The evidence for the link is strongest for certain pesticides, like paraquat, but industrial solvents, like trichloroethylene (TCE), are also likely major contributors. Air pollution has been less studied but could also be influential.
Do we know why pesticides are linked to Parkinson’s?
Many pesticides are nerve toxins, targeting the parts of cells that are known to be damaged in Parkinson’s, and dissolve in fat, which is the principal make-up of the brain. When you give some of these pesticides to mice and rats, they get Parkinson’s.
Were you surprised by the significance of environmental factors when working on your book, ‘Ending Parkinson’s Disease’?
Yes. I knew about the link between pesticides and Parkinson’s, but I did not know the extent of the evidence, and the strength of the relationship between them. I also didn’t know that chemicals like TCE are the most common contaminant of water found underground and contaminate thousands of sites around the US – including one 15 minutes from my home in suburban Rochester, New York.
Who is most at risk of being affected by pesticides?
Numerous studies suggest that farmers are at a 50 to 200% increased risk, and that residents of rural areas and drinkers of well water are also at higher risk. A registry of Parkinson’s in Nebraska, US, has shown the rates of the condition in the country’s rural areas are two to four times higher than in urban areas like Omaha.
Globally, the areas of the world that are most industrialised, like the US and western Europe, have the highest rates of the condition. Areas that are least industrialised, such as sub-Saharan Africa, have the lowest rates, and those that are going through the most rapid industrialisation, like China, have the highest rates of increase.
However, we have been unwilling to invest in these areas to our collective detriment.
Do you have any advice for readers who are concerned about the impact of environmental factors on their health?
Read our book. We wrote it for you – not for researchers – and it is dedicated to those who bear the burden of the condition. All of its authors are devoting the proceeds to efforts to end Parkinson’s. We have a limited number of copies available for free if cost is an issue – email us at info@endingPD.org to find out more.
The best way to change the course of Parkinson’s is activism from those most affected. A March of Dimes changed the course of polio, activism prevented millions of us from being infected with HIV, and ribbons have raised awareness for breast cancer. We need to end the silence on Parkinson’s.
Need to know: Dr Ray Dorsey
Dr Ray Dorsey is David M Levy Professor of Neurology and Director at the Center for Health + Technology at the University of Rochester Medical Center, US, which has conducted more than 100 clinical trials – including trials that led to the approval of four Parkinson’s medications. He recently co-wrote the book,‘Ending Parkinson’s Disease: A Prescription for Action’.
Environmental factors and Parkinson’s
Researchers believe that a combination of genetic and environmental factors can cause Parkinson’s. Chemicals, viruses, bacteria and heavy metals have all been linked to the condition – this could be because they may cause neurons that produce dopamine to die. Scientists have also suggested a connection between herbicides and pesticides, and Parkinson’s.
To find out more about the causes of Parkinson’s, please visit the EPDA website.
13-year-old redesigns Parkinson’s tulip, the international symbol of the condition
Winning design for Parkinson’s awareness T-shirt announced
6 days ago
Why is it harder to cross obstacles when you have Parkinson’s disease?
A team of researchers at São Paulo State University, Brazil, have offered insights on why people with Parkinson’s disease can find it more difficult to cross obstacles than those without the condition. As part of the study, 13 people with Parkinson’s disease and 11 controls stepped over an obstacle 15 times, and scientists measured the distance between the foot and the obstacles during the step. They found that step-length synergy – the ability of the musculoskeletal system to adapt movement when encountering an obstacle – was 53% lower in people with the condition. “There are patients in our exercise group who fall three or four times a week,” said Fabio Augusto Barbieri, one of the study authors. “It’s important to understand how these patients’ gait and locomotion adapt while crossing obstacles so that we can improve step-length synergy.”
This April, The World Parkinson Coalition is launching The Parkinson Tulip Project – a global collaborative photography campaign to raise awareness of the world’s fastest growing neurological disease. As part of the campaign, which is supported by Supernus Pharmaceuticals, members of the Parkinson’s community are invited to share a photo of themselves with tulips – the official symbol of Parkinson’s disease. The project will run until April 2022, and all images shared by the community will be displayed at the sixth World Parkinson Congress in Barcelona, Spain. Additionally, every photo submitted will be entered into The Parkinson Tulip Project raffle. The World Parkinson Coalition hopes that the project will “give a face and name to those impacted by Parkinson’s” and “inspire the community, reminding people touched by Parkinson’s disease that they are not alone”.
Looking after dental health with Parkinson’s disease
Parkinson’s disease symptoms and medications can cause dental health problems – including difficulty cleaning teeth and increased tooth decay. Now, a study from researchers in Brazil has offered dental care recommendations to help people living with the condition. Analysing data from 14 studies, the scientists highlighted people with Parkinson’s can have “reduced quality of oral health and hygiene”. Their advice included routine teeth-brushing, as well as regular trips to a dentist. They also suggested brushing teeth with both hands, as symptoms like tremor and rigidity could mean using one hand is more difficult. The researchers wrote: “Although oral diseases are largely preventable, they are among the most prevalent diseases globally, thus creating a public health problem. “Despite the relatively low level of evidence in studies on oral health among patients with Parkinson’s disease, the data retrieved for this systematic review allowed us to create a set of simple guidelines.”