Would France be overwhelmed by its pesticides – even those whose use is now prohibited? After being spread on the fields, they have infiltrated our basements. Over the years, their degradation produces new molecules, metabolites. These metabolites can contaminate the water resources of many municipalities, and even end up in tap water. But for lack of sufficient scientific studies, their possible effects on health are not well known.
A precautionary principle not always applied
What do the regulations say about this? If in doubt about a metabolite, ANSES, the National Health Security Agency, classifies it as “relevant”. When a relevant metabolite exceeds the quality limit, set at 0.1 micrograms per litre, the water is declared “non-compliant”. But for its consumption to be prohibited, a second threshold must be reached: the “Maximum health value”, or Vmax. However, for many molecules, it is not possible to determine it, for lack of scientific knowledge. In such a case, water containing more than 0.1 micrograms of metabolite per liter may be prohibited for consumption. But this precautionary principle is far from always being applied, as discovered by “Complément d’Enquête”…
In 2021, 3,307 municipalities, i.e. nearly 1 in 10, experienced the quality limit exceeded at least once for metabolites without Vmax.
This is the conclusion reached by the journalists by compiling the results of hundreds of thousands of water health checks carried out in 2021. They then classified them by department, by molecule, and by overrun noted.
Desphenyl chloridazone (a metabolite derived from a herbicide used in beet cultivation and banned since 2020) was, for example, detected in Merlieux-et-Fouquerolles at 12.46 micrograms per liter, well above the standard. In this municipality of Hauts-de-France, if the precautionary principle were strictly respected, it should be forbidden to drink tap water… However, on the municipal panels which display, as provided for by law, the results of the controls sanitary facilities, the supply water is declared “in conformity with the quality requirements in force for all the parameters controlled”, therefore consumable…
National record in Merlieux-et-Fouquerolles (Hauts-de-France)
But what pesticides, which are not mentioned? They were also tested on April 13, 2021, but the document presenting these results is not visible on the notice board outside the town hall… They notably show the presence of desphenyl chloridazone quantified at 12.46 micrograms per litre. That is 124 times more than the quality limit set at 0.1 micrograms per litre. This is the French record…
The consumption of water not being prohibited by the health authorities, the mayor (now deceased) would not have deemed it necessary to inform the population – or even his municipal councillors, according to their statements. The mayor is responsible for the distribution of tap water, but it is not he who decides whether or not to authorize its consumption; it is the prefecture. Why did that of Aisne not apply the precautionary principle recommended by the General Directorate of Health? At this time of filming, the prefecture refused interview requests from “Complément d’Enquête”, but made a written response to the journalists. It emphasizes that this metabolite, desphenyl chloridazone was “classified as relevant only for lack of sufficient data, and not in the presence of a proven health risk”. And claims to have put in place a monitoring program with reinforced controls…
Excerpt from “Is tap water (really) drinkable?”, a document to see in “Complément d’Enquête” on 22 september 2022.
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