Originally published 2019-01-24.
Yes, France really did go further than the rest of the European Union on bee-harming pesticides. From 1 September 2018, under a biodiversity law passed in 2016, France banned five neonicotinoid insecticides: clothianidin, imidacloprid, thiamethoxam, thiacloprid and acetamiprid. The EU had agreed earlier that year to stop outdoor use of only the first three. The French ban also covered greenhouses, where the EU still allowed them.
That headline needs one honest footnote. France did not ban every pesticide that can hurt bees, and the ban did not stay airtight: sugar beet growers later won temporary exemptions, which a French court struck down in 2023. Here is what the chemicals do, why the ban happened, and how it has held up.
What neonicotinoids are and why bees are exposed
Neonicotinoids are a family of synthetic insecticides chemically related to nicotine. Bayer patented imidacloprid, the first commercial one, in 1985, and by the late 1990s it was spreading quickly across farms worldwide. For years it was the most widely used insecticide on the planet.
They work on the insect nervous system. The molecules latch onto nicotinic acetylcholine receptors, the switches that carry nerve signals. A small dose overstimulates the insect; a larger one blocks the receptors entirely, causing paralysis and death. Because insect receptors bind these chemicals far more tightly than mammalian ones, the products are much more toxic to insects than to people, which is a big part of why farmers welcomed them as a step up from older, harsher sprays.
The catch is that neonicotinoids are systemic. Applied as a seed coating, they are absorbed by the growing plant and spread through its tissues, including pollen and nectar. A bee visiting a treated flowering crop, or wildflowers growing in contaminated soil nearby, can take in small amounts with every visit. Dust from coated seeds during sowing is another route.
What research says about the harm to bees
Most of the concern is about sublethal effects: doses too low to kill a bee outright that still change how it behaves and breeds. Studies have linked chronic exposure to trouble with navigation and learning, poorer foraging, weaker immune responses, lower sperm viability in drones, shorter-lived queens and fewer new queens. A forager that cannot find its way home is as lost to the colony as a dead one.
In 2013 the European Food Safety Authority found a high acute risk to honeybees from some seed-treatment uses. Its larger review in February 2018 went further, concluding that most outdoor uses posed a risk to both wild bees and honeybees. That assessment is what pushed EU governments to act.
The science is not one-sided, and it is fair to say so. Some field studies have failed to reproduce harm seen in the lab, possibly because lab doses were higher than bees meet in real fields. Bumblebees and solitary bees often appear more vulnerable than honeybees, which have been studied most.
Two common myths: addiction and colony collapse
You will often read that bees get "addicted" to neonicotinoids. The research behind that claim is a 2015 study in Nature led by Sébastien Kessler and Geraldine Wright. Given a choice, honeybees and buff-tailed bumblebees drank more sugar solution laced with imidacloprid or thiamethoxam than plain sugar water. The authors found that bees could not taste the chemicals at all, so they had no way to avoid them. That is a preference with real consequences, but "addiction" goes beyond what the study showed.
The second myth is that these pesticides were proven to cause colony collapse disorder, the sudden disappearance of worker bees that alarmed beekeepers from around 2006. Researchers now see colony losses as the result of several stresses acting together: varroa mites and the viruses they spread, poor nutrition, loss of wildflowers, and pesticides among them. Many collapsed colonies show no trace of neonicotinoids at all. The more defensible claim is that these chemicals can make bees more vulnerable to the other threats.
How France's ban compared with the rest of Europe
The EU first restricted imidacloprid, clothianidin and thiamethoxam on bee-attractive crops in December 2013. On 27 April 2018 member states agreed to end all outdoor use of those three, leaving only permanent greenhouses. The change took effect at the end of 2018.
France had already written its own wider rule into law. Its 2016 biodiversity act set a September 2018 start date and named the whole class, adding thiacloprid and acetamiprid to the list and covering greenhouse use. Thiacloprid later lost its EU approval in 2020, so on that one the rest of Europe eventually caught up.
Britain's position also shifted. The UK did not support the first EU restrictions in 2013, but in November 2017 the government announced it would back a wider ban, citing new evidence on the risk to bees.
Farmers' objections and the sugar beet exemptions
Beekeepers and environmental groups welcomed the ban. Many arable farmers did not. Growers of sugar beet and cereals warned that they would be left with fewer tools against aphids and other pests, and that farmers in countries without such rules would gain an unfair price advantage. France's largest farm union, the FNSEA, asked for exemptions wherever no workable alternative existed and questioned the strength of the evidence on bee decline.
The French food and environmental safety agency, ANSES, took a different view in its assessments, finding that effective alternatives already existed for most uses, whether other chemicals or non-chemical methods.
Sugar beet became the flashpoint. In 2020 aphids spread beet yellows virus through French fields and yields fell sharply. A law of 14 December 2020 let the government grant temporary exemptions for beet seed coated with imidacloprid or thiamethoxam, and these were used in 2021 and 2022.
They did not survive the courts. On 19 January 2023 the Court of Justice of the European Union ruled that a member state cannot grant an emergency exemption for a seed treatment the European Commission has expressly banned. On 3 May 2023 France's Conseil d'État applied that ruling and revoked the 2021 and 2022 exemptions as illegal.
The debate reopened in 2025, when French lawmakers passed a farm bill that would have allowed acetamiprid back under conditions. A public petition against it gathered well over a million signatures, and in August 2025 the Constitutional Council struck down that provision.
What this means if you care about bees
A ban on one class of chemicals is a significant step, but it is not a cure on its own. Pollinators also need food and shelter through the whole season, and that is where individuals can help:
- Plant a mix of flowers that bloom from early spring to autumn, and leave some lawn unmown.
- Check labels on garden insecticides and avoid spraying open flowers, especially on sunny days when bees forage.
- Be wary of nursery plants pre-treated with systemic insecticides; ask the seller if unsure.
- Buy honey from local beekeepers, who track colony health closely and often know the local pesticide picture.
France's decision mattered because it showed a large farming nation could legislate ahead of the EU and keep most of its rules in place despite pressure. The sugar beet episode shows the other side: such bans hold only as long as courts, scientists and the public keep watching.
Sources: Wikipedia: Neonicotinoid; Kessler et al., Bees prefer foods containing neonicotinoid pesticides, Nature (2015); Conseil d'État: Neonicotinoids, no exemptions to the European ban (3 May 2023); Britannica: Colony collapse disorder. Photo: Luca Biada via Flickr.
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