Global atlas of pesticide use

Imagine the Earth as a giant, living garden. To keep this garden from being eaten alive by hungry bugs, weeds, and fungi, farmers use special chemical tools called pesticides. Think of these chemicals like a gardener's spray bottle: some are for killing weeds, some for stopping bugs, and some for fighting fungal diseases. But just like a real gardener needs to know exactly how much spray to use, where to spray it, and when to spray it, the whole world needs to know how these chemicals are being used on a massive scale. If we use too much, or use it in the wrong way, it can hurt the soil, the water, and even our own health. For a long time, figuring out exactly how much of these chemicals is used, where, and on what crops has been like trying to count the stars in a cloudy sky—we knew they were there, but the details were fuzzy, missing, or hidden in different notebooks around the world.

This is where a new, massive project steps in to clear the fog. A team of scientists from universities and industry partners has built the first-ever "Global Atlas of Pesticide Use." Think of this atlas not as a map of roads and cities, but as a super-detailed, high-definition video game map of the world's farms. Instead of just saying "Country X uses pesticides," this map zooms in to show exactly which chemical is used on which crop, at what time of the plant's life, and how it's sprayed. They crunched data from 2016 to 2020, combining official government reports, market research, and expert estimates to create a picture of the world's agricultural habits. Their goal was to turn a blurry, patchy picture into a sharp, clear image so we can see where the "hotspots" of chemical use are and figure out how to make farming safer and more sustainable for everyone.

The Great Pesticide Map

So, what did this team actually find when they turned on the lights and looked at their new map? First, they discovered that the world is using a staggering amount of these chemicals. Between 2016 and 2020, farmers applied an average of 2.9 million tonnes of pesticide every single year. To put that in perspective, that's enough to fill a huge line of trucks stretching around the globe.

The map revealed that this usage isn't spread out evenly like sprinkles on a cookie. Instead, it's concentrated in specific places. Just three countries—China, the USA, and Brazil—are responsible for nearly half (45%) of all the pesticide mass used worldwide. Even more interesting, these three countries only treat about 25% of the total farmland area, meaning they are using a massive amount of chemicals on a relatively smaller slice of the world's crops. Following them are countries like Argentina, India, Australia, Japan, Spain, and Canada, which together add another 22% of the total.

When the scientists looked at what kind of chemicals were being used, they found that herbicides (weed killers) are the big winners, making up 53% of the total mass. Fungicides (for fighting fungus) and "other" pesticides each take about 17%, while insecticides (bug killers) make up 13%. The most famous name on the list is glyphosate, which is used at a rate of 0.79 million tonnes per year. It's followed by sulfur, mancozeb, and atrazine.

The "How" and "Where" Matters

One of the coolest things about this atlas is that it doesn't just count the chemicals; it explains how they are used. The scientists found that the amount of spray needed can vary wildly depending on the job. It's like the difference between using a tiny dot of glue to fix a paper cut versus using a whole bucket of it to seal a roof.

The application rates (how much chemical is put on one hectare of land) swing over six orders of magnitude.

• The Light Touch: Some treatments, like putting insecticides on seeds before they even sprout, use a tiny amount, with a median of just 0.07 kg/ha.
• The Heavy Hitters: On the other end, clearing soil before planting (like fumigation) can use up to 80 kg/ha.

The map also showed that the type of crop matters a lot. Perennial crops (plants that live for many years, like fruit trees) get about 2.5 times more pesticide per hectare than cereals (like wheat or corn). And climate plays a role too; in hotter, more humid places, farmers often need to use more diverse and heavier doses of pesticides because pests love warm, wet weather.

Hotspots and Surprises

The atlas acts like a heat map, lighting up the "hotspots" where pesticide use is most intense.

• Soybeans are the biggest target, soaking up 14.4% of the global pesticide mass, mostly in Brazil, the USA, and Argentina.
• Maize, wheat, and rice are also major players, treated in many countries.
• Some countries have very specific habits. For example, Japan has the highest "annual load" (pesticide per hectare of crop area) because of the heavy use of cyanamide on root crops. Israel stands out for using high amounts of formaldehyde and other chemicals on fruits and nuts.

The researchers also found some worrying details. Even though some chemicals are banned or severely restricted in many parts of the world, the map shows they are still being used. Specifically, 73 banned or severely restricted chemicals are still being applied across 48 countries, totaling 24.2 million kg per year. This suggests that while rules exist, they aren't always followed everywhere.

How They Built the Map

You might wonder, "How did they get all this data?" It wasn't easy. They gathered information from three main sources:

1. Official Panel Data (71%): Surveys of farmers in places like China, the USA, Brazil, and Europe.
2. Industry Statistics (27%): Estimates from market experts, especially for parts of Latin America, Asia, and Africa where official data was missing.
3. Market Research (2%): Data for places like Canada and parts of Africa.

They had to clean up the data, throwing out about 10% of it because of errors, like negative numbers or impossible chemical names. For the 68 countries that had no data at all (mostly in Sub-Saharan Africa), they used smart computer models (machine learning) to guess what was likely being used based on the climate, the crops grown, and the country's economic development. They also filled in the gaps for missing details like when the spray happened (crop growth stage) and how it was sprayed (aerial, boom sprayer, etc.).

Why This Matters

This atlas is a game-changer because, for the first time, we have a clear, detailed view of the global pesticide landscape. Before this, we mostly had rough estimates or data that was lumped together in big, unhelpful categories. Now, we can see exactly where the problems are.

The authors suggest that this data is crucial for making better policies. If we know exactly where and how pesticides are being used, we can:

• Set better targets for reducing chemical use.
• Understand the risks to bees, water, and human health.
• Find better ways to protect crops without relying so heavily on chemicals.

However, the paper is careful to note that this is a snapshot of the past (2016–2020). Regulations change, and new chemicals are approved or banned all the time. For instance, a chemical like mancozeb was still widely used in 2020 but has since been banned in the European Union. So, this map needs to be updated regularly to stay accurate.

In short, this paper gives us the first high-resolution "Google Earth" view of how the world protects its food. It shows us that while we are using a lot of chemicals, the patterns are complex and vary wildly from place to place. By shining a light on these patterns, we can start the conversation about how to farm smarter, safer, and more sustainably for the future.