Here, I relate what the journalist said in his article “Des niveaux alarmants de pesticides mesurés dans les sols et les vers de terre”. All quotes, originally in French, were translated by me.
The Senate would have adopted, on October 27, the reauthorization of NNIs for sugar beets. At the same time, published online at the end of September in Agriculture, Ecosystems & Environment, a study carried out on the Plaine and Val de Sèvre workshop area would show the impact of pesticides on soils and earthworms (Pelosi et al. 2020). The researchers, including Vincent Bretagnolle, took samples from various areas (agricultural, conventional or organic plots, meadows and hedges that had never been treated, etc.) to study the presence of 31 pesticides. They would have found
- at least one pesticide in all the samples analyzed;
- a mixture of at least one insecticide, fungicide and herbicide in 90% of the samples;
- more than ten different pesticides in 40% of cases.
This study would be very original, such data on contamination being “surprisingly rare”.
“The four most commonly found substances are diflufenican (a herbicide), imidacloprid (a neonicotinoid insecticide) and two fungicides, boscalid and epoxiconazole. At least one of these four substances is detected in more than 80% of the soils analyzed. “
The researchers also studied the earthworms present in the soils. They found it in 155 samples out of 180 and imidacloprid in 80% of the earthworms, sometimes in astronomical concentrations:
“The concentrations found are spectacular: 43% of earthworms have an imidacloprid level of more than 100 ppb [parts per billion] and 8% have more than 500 ppb”, specifies Mr. Bretagnolle. The maximum recorded is close to 780 ppb. That is, for example, a concentration almost 400 times higher than what is measured in rapeseed nectar, when the latter is treated with imidacloprid. “
This is believed to be a sign of bioaccumulation, which may have been overlooked by EFSA, which considered imidacloprid to be “at low risk of bioaccumulation”. Researchers have also reportedly found other pesticides in earthworms, all of which pose “a high risk of chronic toxicity.” It would also be worrying on a larger scale, in particular, for example, for birds feeding on said earthworms.