MONTREAL – Two scientific literature reviews published today show links between exposure to certain pesticides widely used in Quebec and the risk of autism and Parkinson’s disease. These reports were produced by Autisme Montréal, Parkinson Québec, Alliance pour l’interdiction des pesticides systémique (AIPS) and the David Suzuki Foundation.

Today, the authors1 Louise Hénault-Éthier, Electra Dalamagas, Isabelle Pitrou and Pascal Priori published a literature review entitled Alarming increase in autism: Should we worry about pesticides? Romain Rigal2 of Parkinson Québec also published the conclusions of his study entitled Parkinson and Pesticides. An established causality. Measures to protect all citizens. The two reports were submitted to the National Assembly of Quebec’s Committee on Agriculture, Fisheries, Energy and Natural Resources, which will be looking into the impacts of pesticides on human health and the environment this fall.

Over the past few years, research has shown that in addition to individual factors, improvements in detection and changes to the DSM diagnostic criteria, environmental factors play a critical role in explaining an increase in the prevalence of autism. The literature review published today cites many studies that present a link between pesticide exposure and the increased risk for a child to develop autism.

“Considering the alarming increase in cases of autism, the accumulation of scientific evidence showing a link between pesticide exposure and the risk of autism requires wide-scale action to protect us against the potential human health impacts of pesticides,” explained Dr. Isabelle Pitrou, physician epidemiologist at Université de Sherbrooke.

The list of pesticides linked to autism is long3. For example, insecticides in the organochlorines, organophosphates and pyrethroids families all affect the development of connections between neurons, which may explain associations with neurodevelopmental disorders. Among the most popular pesticides indicated in these studies are DDT (banned today but still present in the environment), chlorpyrifos (whose renewal of approval in Europe received a negative EFSA scientific opinion), as well as popular glyphosate-based herbicides.

“Insecticides are designed to interfere with synaptic transmission in the central nervous system, however, neurotoxic properties of pesticides may have unintended consequences in the brain of developing children,” explained biologist Louise Hénault-Ethier, co-author of the study and Science Project Manager for the David Suzuki Foundation. “With extensive use of such substances in agricultural practice — approved by our federal and provincial regulatory bodies — corporations have been able to use the population of Quebec and Canada as guinea pigs, and now we see what could be one of the most harmful consequences of this careless and poorly controlled experiment.”

“Exposure to environmental toxins such as pesticides needs to be minimized, as epidemiological studies show that there is a high risk for fetuses to develop autism,” explained Electra Dalamagas, who is responsible for family intervention at Autisme Montréal. “This report underlines how our view of prenatal health must also change. In essence, prenatal health and the health linked to the neurological development of a fetus starts well before time of conception, and is directly dependent on the physical environment of future parents – as well as toxic products found within these environments. The concern regarding pesticides is even greater as their consequences can transcend generations.”

According to co-author and spokesperson for Alliance pour l’interdiction des pesticides systémiques, Pascal Priori: “On one hand, there is a significant increase in autism in Quebec without any action taken against potential contributing factors. On the other hand, the independent scientific research clearly shows the association to pesticides. We overuse pesticides even though we know how to do without them. Yet governments continue to approve pesticides based on an outdated and biased process. The status quo or reassuring speeches are no longer adequate — we need swift action to protect our children.”

As for the link between pesticide exposure and the increase in cases of Parkinson’s disease, it was first observed in Quebec in the 1980s. Since the 1990s, more than 100 studies have been conducted to evaluate the link between these two phenomena. The results of these epidemiological works have been summarized in eight meta-analyses that unanimously conclude that the risk of developing Parkinson’s disease is doubled following pesticide exposure. This association is unanimously accepted in the scientific community, which uses certain pesticides, such as rotenone and paraquat, to create animal models of Parkinson’s.

“Nearly 40 years after the first theories on the link between pesticide exposure and the development of Parkinson’s disease, the Quebec government now has enough evidence showing the causal role of pesticides in Parkinson’s. Additional scientific research is in fact needed to better determine the products and the most toxic doses, but immediate action must be taken to protect all citizens, including our children in particular, whose nervous system is the most sensitive, and who are the most vulnerable to exposure. Their risk of developing the disease is up to six times higher.” Moreover, added Romain Rigal from Parkinson Québec: “This increased risk is not limited to farmers, but it also affects the entire Quebec population living near pesticide application sites or those who use pesticides at home.”

The authors of the two studies published today urge the Quebec government, the Committee on Agriculture, Fisheries, Energy and Natural Resources, Health Canada and the Pest Management Regulatory Agency (PMRA) to do everything in their powers to limit the population’s exposure to these substances, especially those used extensively in agriculture.

It is crucial to take action to prohibit any use of pesticides that are dangerous to our health and to stop the introduction of dangerous new pesticides by thoroughly reforming the registration process. Promoting non-toxic alternatives as well as assessing serious risks by conducting more research, such as longitudinal epidemiological studies, must be among the potential solutions prioritized by government.

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The reports are available here:

For more information or to arrange an interview, please contact:

Diego Creimer, David Suzuki Foundation, 514-999-6743

Charlotte Bichon, Parkinson Québec, 514-861-4422, ext. 269


  1. Authors: Louise Hénault-Ethier, PhD, Science Project Manager for the David Suzuki Foundation; Electra Dalamagas, MSW, Responsible for Family Intervention, Autisme Montréal; Isabelle Pitrou, PhD, Physician Epidemiologist at Université de Sherbrooke; Pascal Priori, MSc, Alliance pour l’interdiction des pesticides systémiques.
  2. Romain Rigal, MSc, Service Development Director, Parkinson Québec.
  3. The list includes carbamates, organochlorines, organophosphates, pyrethroids, neonicotinoids, organobromines and macrocyclic lactone derivatives. DDT and its derivative DDE, chlorpyrifos, diazinon, malathion and avermectin also appear among the pesticides associated with autism, as well as permethrin, cypermethrin, bifenthrin, imidacloprid, dicofol, endosulfan and methyl bromide. Besides insecticides, herbicides glyphosate and ammonium glufosinate; fungicides myclobutanil, phosphine, pyraclostrobin, trifloxystrobin, famoxadone and fenamidone; as well as rodenticides have also been listed in studies showing correlations with autism.