A Journey Through France

Have you ever visited France ? Picture Peter Herrmann

Let’s take a tour of the country together.

This is a map of population density in mainland France, using data from the Global Human Settlement Layer project.

White lines represent regional boundaries, blue pixels show the most populated areas.

For example, here is the Île-de-France region, with Paris in the center. Picture Nuno Lopes

But I also want to tell you about another map of France.

This one is a map of the number of pesticides applications per year.

It was obtained by taking into account all fields declared to the Common Agricultural Policy, and applying an average number of treatments per crop and per region.

Red pixels show the areas with the highest number of pesticides applications.

This is particularly the case in Northern France because of the cultivation of industrial crops (sugar beet, potatoes) which require a high number of treatmentst: potatoes receive around 20 pesticide applications a year, compared with 3 for maize, for example. Picture Piotr Zakrzewski

…but also because of a higher number of treatments for a given crop in Northern France compared to other regions, as illustrated below for soft winter wheat.

This can be explained by more intensive farming systems and weather conditions that favor crop disease development in Northern France.

Any idea what is coming next ?

[…last chance to take a guess…]

By combining the two maps, we obtain a map of the population’s exposure to pesticides.

Let’s take a close look at the legend.

Approximately 25 % of the population is exposed to at least one pesticide application per year less than 100m from their home.

This figure varies greatly from region to region.

For example, in Brittany, over 45% of the population is exposed to at least one pesticide application per year.

Such a result can be explained by the proximity of housing to fields in this region, with many small urban areas intermingled with agricultural areas.

But some people are more sensitive to pesticide exposure than others.

Ten years ago, 28 pupils and their teacher at a school in the Bordeaux vineyards experienced illness when pesticides were sprayed near their playground. Source Jérôme Jamet, France Info

Like potatoes, vines receive a large number of pesticide treatments (around 15 a year for Bordeaux vineyards, for example).

The following map will allow you to explore the school’s surroundings.

A few years earlier, pesticide use had been suspected in the development of pediatric cancers in another commune of the same region.

The ensuing epidemiological study highlighted the high level of wine-growing activity in the study area, with pesticide spraying in the vicinity of the school.

Again, you may explore the school’s environment with the following map:

But in that case a lack of data made it impossible to conclude on the link between pesticide use and pediatrics cancers.

We hope that the map of pesticide treatments in France that we have developed may help to elucidate this issue.

In fact, in the same way that we as we combined the map of pesticide applications with population density, this map can also be crossed with the location of schools in the country to create a map of pupils’ exposure to pesticides.

For example, here is a map of the 1,663 schools exposed to more than 10 pesticide applications per year.

The Bordeaux wine-growing area is indeed one of the regions concerned.

… as is the case for the Burgundy vineyards.

… but also in the field crop regions of northern France.

Unfortunately, the youngest students are the most exposed to pesticides applications.

This is due to the fact that schools for the youngest children are scattered throughout the territories, while high schools are concentrated in the cities.

Recent research has highlighted a potential harmful effect of pesticide treatments on children.

In North America, Frank (2024) showed that the decrease of insect-eating bat populations led to an increase in insecticide treatments, which in turn has led to an increase in infant mortality in the affected regions.

Such research depend on reliable, accurate and easily accessible quantification of pesticide use.

Hence, to facilitate the implementation of similar epidemiological studies in France, the map of pesticide use we presented here is freely downloadable at this link.

To go further

Click on the pictures below to explore additional ressources: