CVM contamination of drinking water has been well known to regional Health agencies (ARS) for several decades, but less from the general public. Vert explains everything to you on this toxic gas in this article. As revealed by our survey, this carcinogenic substance released by PCV pipes of the years 1960-1980 continues to exceed the regulatory limit of 0.5 μg/L (microgram per liter). Hundreds of thousands of French people are or have been exposed to harmful doses of CVM.
This article is the second part of a series of articles on monomeric vinyl chloride, a toxic and carcinogenic gas present in many PVC pipes and yet largely unknown by the general public. A three -part survey carried out for Vert By Hugo Coignard, Marie-Aimée Copleutre and Marti Blancho, of the collective of independent journalists in ENKETO.
In order to measure the magnitude of this pollution, we have analyzed two complementary data games. On the one hand, the results of the samples taken from the drinking water network concerning the CVM, obtained by Gaspard Lemaire, doctoral student in political science for the Earth chair of the University of Angers, with the ARS who were kind enough to communicate them. On the other, the results of the health control of the distributed water, made available by the Ministry of Solidarity and Health.
After combining these two sources, we had to find all the municipalities connected to each drinking water distribution network affected by an exceeding the CVM limit. In the end, we identified 5,506 localities with at least one result more than 0.5 μg/l. It should be noted that the same installation can water several municipalities and that the different districts of the same city can be connected to different networks. Finally, if a municipality does not appear on the map, it is that no measure exceeds the threshold or that it could not be identified (see methodology, below).
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Methodological notes
Some analysis results are preceded by a lower sign “<". To be able to compare them to others in a coherent way, we have removed this sign in order to keep only the absolute value. In addition, we only kept the results strictly superior to the regulatory limit (0.5 μg/L). However, these results are subject to "a margin of error up to 40%, depending on the analytical capacities of the laboratories", recalls Gaspard Lemaire.
Part of the data obtained from the ARS were devoid of the code to identify the distribution network corresponding to the levy, and therefore the municipalities concerned. This card is therefore only a partial photograph of the contamination of France to the CVM. The absence of a municipality therefore does not indicate that it is spared by pollution.
