Researchers have detected dozens of agricultural chemicals—including insecticides, herbicides, and fungicides—in clouds over France. These pollutants eventually fall back to Earth as rain or snow, in some cases at highly concentrated levels.
Who needs chemtrails or geoengineering when reality is worse? A new study delivers catastrophic data for both humans and the environment: clouds over Europe are contaminated with dozens of pesticides that eventually descend to the ground with rainfall or snow. These chemicals, including substances already banned, could have far-reaching impacts on ecosystems, drinking water, and human health.
This first-of-its-kind study was published on September 8, 2025, in the journal Environmental Science & Technology. For the first time, a wide array of agricultural chemicals has been detected in clouds over France. The organization Children’s Health Defense reported on the findings.
Researchers identified insecticides, herbicides, and fungicides, including ten substances already banned in the European Union. Every sample was contaminated, and in two cases, concentrations exceeded the EU drinking water threshold of 0.5 micrograms per liter. Measurements were taken at Puy de Dôme, a mountain observatory in France that is part of international networks such as ACTRIS and the World Meteorological Organization’s Global Atmosphere Watch. Out of 446 tested chemicals, 32 were detected, including new breakdown products and pollutants like 2,4-dinitrophenol, which exceeded safety limits. Many of these pesticides are not local in origin but are transported long distances through the atmosphere.
They enter the air via evaporation or wind drift, a mechanism known as the “grasshopper effect.” As much as half of the 2.6 million tons of pesticides used worldwide annually may escape into the atmosphere in this way.
In clouds, they act as “chemical reactors”: moisture binds the pollutants into droplets where they can undergo chemical changes. For example, triphenyl phosphate is transformed into diphenyl phosphate within 90 minutes in cloud water. The study estimates that clouds over France may contain between 6 and 139 tons of pesticides at any given time—about 0.2 percent of the country’s annual pesticide use.
The most heavily contaminated samples came from air masses that had passed over farmland during the spraying season, while samples originating from Atlantic or forested areas showed lower concentrations.
Notably, the study found banned substances such as atrazine (prohibited since 2003) and carbendazim (since 2008). These likely originate from countries outside the EU, where their use is still permitted, and travel through the atmosphere.
Pesticides are linked to severe health risks: they can trigger cancers in children and adolescents, cause neurological disorders, and contribute to problems with reproduction, respiratory systems, metabolism, and development—including infertility, premature births, Parkinson’s disease, and type 2 diabetes.
