Philippe Grandjean says to himself ” very worried “ the levels of pesticides to which Europeans are subjected. According to him, each European ingests an average of 300 g of pesticides per year. 50% of the foods that we consume regularly (fruits, vegetables, cereals) would have the residues of a pesticide and 25% would be contaminated by several of these chemicals.

The major risk lies in the synergy of the effects of pesticides, which according to the doctor-researcher, is not sufficiently taken into account by the European Food Safety Authority (EFSA). For the moment, this establishes toxic thresholds for each pesticide (including insecticides, fungicides, herbicides, etc.) taken separately.

The impact of pesticides on brain development

According to Professor Grandjean, it is on “Our most precious organ”, the brain, that this cocktail of pesticides would cause the most disastrous damage. This vulnerability is all the more important when the brain is developing “It is the fetus and the early stage child who suffer from it”.

The scientist bases his remarks on a series of studies carried out on young children around the world. One of them compared the brain development of two groups of 5-year-olds with similar characteristics in terms of genetics, diet, culture and behavior.¹. Although coming from the same region of Mexico, one of the two groups was subjected to high levels of pesticides, while the other did not.

Result: Children exposed to pesticides showed decreased endurance, coordination, short-term memory as well as the ability to draw a person. This last aspect is particularly obvious. 

During the conference, the researcher cites a series of publications, each more worrying than the last. A study shows, for example, that the gradual increase in the concentration of organophosphate pesticides in the urine of pregnant women is correlated with the loss of 5,5 IQ points in children at the age of 7 years². Another shows clearly on imaging of brains damaged by prenatal exposure to chlorpyrifos (CPF), a commonly used pesticide³.

Acting under the precautionary principle

Despite these alarming results, Professor Grandjean believes that too few studies are looking at the subject at present. Moreover, he judges that « l’EFSA [European Food Safety Authority] must take studies on the neurotoxicity of pesticides seriously with as much interest as those on cancer. 

At the end of 2013, however, EFSA had recognized that exposure of Europeans to two insecticides – acetamiprid and imidacloprid – could adversely affect the development of neurons and brain structures associated with functions such as learning and Memory. Beyond a drop in toxicological reference values, the agency’s experts wanted to make the submission of studies on the neurotoxicity of pesticides compulsory before authorizing their use on European crops.

For the professor, waiting for the results of the studies would waste too much time. European decision-makers must act quickly. “Do we have to wait for absolute proof to protect what is most valuable? I think the precautionary principle applies very well to this case and that the protection of future generations is important in decision-making. “

“So I send a strong message to EFSA. We need to protect our brains more vigorously in the future ” hammers the scientist. What if we started by eating organic?

Philippe Grandjean is professor of medicine at the University of Odense in Denmark. Former adviser to the WHO and EFSA (the European Food Safety Agency), he published a book on the impact of environmental pollution on brain development in 2013 « Only on chance — How Environmental Pollution Impairs Brain Development – and How to Protect the Brains of the Next Generation » Oxford University Press.

Access the retransmission of the workshop organized on November 18, 2015 by the Scientific and Technological Choices Assessment Unit (STOA) of the European Parliament.