Reporterre’s revelations on Tuesday, October 13 aroused turmoil in the midst of the Covid-19 epidemic. The information site specializing in ecology revealed that the fabric masks of the Dim brand provided by the National Education to teachers were treated with a biocidal chemical considered toxic: zeolite of silver and copper. This information raises questions which the “True or Fake” cell of franceinfo is trying to answer.
What masks are we talking about?
At the start of the school year in September, the National Education distributed fabric masks to each teacher. “The rule was five masks each minimum, but some colleagues received only two”, specifies to franceinfo Catherine Nave-Bekhti, general secretary of the SGEN-CFDT union.
But teachers were not the only ones to receive fabric masks from the Sun brand. After a week of controversy, the government finally recognized it, Tuesday, October 20, in a press release from Bercy. The State, which bought them from the lingerie manufacturer “in spring”, also distributed them “to state civil servants and associations”.
One of these masks was even worn by Emmanuel Macron, during a trip to a high school in Clermont-Ferrand in early September. He had also had a coughing fit and had said: “Sorry, I’m choking. (…) I’m going to put on a lighter mask, because I must have absorbed something from the mask. “
The general public was also able to obtain them on online sales sites and, at least until Tuesday, on the website of Dim. The brand announced in a press release Wednesday, October 21 that it was suspending their marketing.
What are zeolites?
Zeolites are minerals. Crystals more precisely. “You can find zeolites in nature, but you can also synthesize them. There are over 240 different types of synthetic zeolites.”, tells franceinfo Svetlana Mintova, CNRS research director at the National School of Engineers in Caen. The particularity of zeolites is to have a porous molecular structure. These crystals can thus absorb other chemical elements. This faculty makes them interesting for the industry in more than one way.
Many common products therefore contain zeolites, exposes Svetlana Mintova. “There are zeolites in the washing powder that we wash our clothes. They are used to remove calcium from water and make it softer during washing.” Given their absorbent power, these crystals are also found in certain cat litter or in substrates for bonsai. “Zeolites are also used as food additives or to extract radioactive elements and heavy metals, as after the nuclear disasters of Fukushima or Chernobyl”, lists the researcher.
Why treat fabric masks in this way?
But the addition of zeolites in fabric masks could have another interest, notes Svetlana Mintova: “Zeolites are also very hydrophilic and can therefore also serve to trap moisture in our breathing.” In addition to an antimicrobial effect, the treatment with silver and copper zeolite applied by Dim could therefore serve to provide additional comfort to wearers of its fabric masks. The latter are also the only textiles of the brand to receive this treatment, assures the company.
Is this chemical treatment authorized?
Dim says he’s applying this zeolite-based treatment to his sheet masks “within the framework of category TP09, in accordance with delegated regulation n ° 1062/2014 and regulation n ° 528/2012 of the European Chemicals Agency concerning the placing on the market and use of biocidal products”. The choice by Dim of this category “type 9” is important.
The European regulation on biocidal products classifies them in 22 types, according to their possible uses. Like other biocides, silver and copper zeolite is subject to an evaluation process at European level. This, entrusted to Sweden, is underway, as indicated on the website of the European Chemicals Agency.
To date, a verdict has not been rendered for silver and copper zeolite only for two of the 22 categories of potential uses: those falling under “type 2” or “type 7”. In these two categories, his use as a biocide has not been approved. The opinion delivered in October 2018 by The European Chemicals Agency was endorsed by a decision of the European Commission in November 2019.
In the absence of a European decision against it in the other categories, thea zeolite of silver and copper can therefore still be used as a biocide, in particular in uses falling under “type 9”. Namely, as a product for “protect fibrous or polymerized materials”, as “textile products”, by preventing “the accumulation of microorganisms on the surface”, by preventing or preventing “the formation of odors” or by presenting more widely “other types of advantages”, according to the regulations.
Are these minerals harmful to health?
Dim assures us that his masks “are sure”. “Our masks comply with the requirements of Standard 100 Oeko-Tex, which means that each of their components has been tested ‘free of harmful substances’ and, therefore, they pose no risk to human health”, guarantees the company. “The tests are done by independent laboratories”, insists the group. A point also underlined by Bercy in its press release. Dim also claims that his masks “contain a very small amount of silver and copper zeolite” and “do not contain zeolite nanoparticles “.
But one point raises questions. In its opinion, the European Chemicals Agency considers silver and copper zeolite as “toxic”, especially for “the reproduction”, because likely to harm the good development of the fetus. LThe European Agency even considers that “the use of textiles [traités à la zéolithe d’argent et de cuivre] intended for direct contact with human skin presents unacceptable risks for all age groups “.
The organization recognizes, however, that it has spoken “in the absence of substance specific information”. She explains that she judged silver and copper zeolite based on known data for other substances with a similar structure (silver and zinc zeolite, silver salts … ), by extrapolating from the information available for each component element zeolite of silver and copper (i.e. silver, copper and zeolite) or by consulting the results of work on silver and copper ions.
Similarly, notes the Ministry of Industry, “a study dating from the end of 2019 highlighted the health risks of these two substances, for a use however different from that declared by the companies producing masks, and in particular of the Dim brand”. And to specify:
This study is based on generic analyzes that do not make it possible to conclude on the toxicity of masks treated with zeolite, given the concentrations present in the masks and the exposure conditions.The Ministry of Industry
in a press release
These methods of analysis are not unanimous, according to Svetlana Mintova. “We cannot compare the toxicity of pure silver nanoparticles (or almost) with silver immobilized in zeolites, she criticizes. The toxicity of pure silver is well known. However, the silver in zeolites exists as low concentration cations, in trace amounts. “
Do these masks present any risks?
The question is: “Is there a risk that particles will come off the mask?”, form with franceinfo Jérôme Mijoin, lecturer at the Institute of Chemistry of Environments and Materials at the University of Poitiers, attached to the CNRS. For him, the answer depends on the manufacture. “Depending on the impregnation method used, the silver incorporated into the zeolite can be more or less ‘labile’ [“instable” en chimie]. It can therefore be expelled from the crystal structure of the zeolite, in particular during washing “, points out Jérôme Mijoin.
Among the range of possible techniques, spraying is in the opinion of Svetlana Mintova the most problematic. “If the zeolite is sprayed dry on the surface of the fabric mask, yes that can be a problem, but I don’t believe a company would produce masks this way.”, judge the researcher. The zeolite would in fact be present only on the surface and the treatment would not last. Dim does not reveal its industrial secrets, but the group argues that the presence of zeolite on its masks is “even more reduced after washing the product”, recommended before first use and after each wearing. This clarification questions both the durability of the treatment and the way in which it was applied.
At this stage, it cannot be concluded that the silver present in the zeolites is dangerous or not, in particular as regards this product.Svetlana Mintova
“One thing is certain, as with all silicic or alumino-silicic compounds, the inhalation and deep penetration of zeolite particles into the pulmonary alveoli is clearly not desirable”, retorts Jérôme Mijoin.
“It is the active metal ions of silver, inserted into the zeolite particles, which can be toxic”, specifies to HuffPost Fabrizio Pariselli, toxicologist, director of the chemical risk prevention unit at CNRS. “In high doses, they can enter the bloodstream and be neurotoxic. They can also lead to weight loss, weaken the immune system, be corrosive to the eyes.”, he lists, adding however that“it takes a very prolonged report and very high doses”.
Other experts contacted by Reporterre believe that, when in doubt, the precautionary principle should apply. “Why give masks with silver ions when there are harmless masks? It is the precautionary principle: do not use potentially toxic product even if it is a tiny dose”, says neuroscience researcher Yves Burnod.
How did the state react?
The State will therefore replace these masks with others that do not contain zeolites. He also asked his other suppliers to certify that their models did not contain zeolites. The Ministry of National Education specifies that the distribution of new masks to teachers is planned after the All Saints holidays. According to Snes, a message is also sent to the staff of National Education asking them to no longer wear them.
Elisabeth Allain-Moreno, National Secretary of Unsa-Education, in charge of quality of life at work, “advises colleagues to fill in the occupational health and safety register in their establishment”. “If one day the health authorities find that these masks present a danger to health, it is only if the personnel are registered in this register that they will be able to demand repairs and damage”, underlines the teacher unionist.
ANSES, the national health security agency, confirms to Franceinfo that it has been tasked with carrying out an expertise by the Ministry for Ecological Transition, in charge of issues related to biocides. “We are going to get closer to the manufacturer to collect all the data necessary for the expertise. We will use the scientific literature on the subject, as we do each time. This work is in progress”, specifies the agency.