Negotiation of a plastic treaty –
Microplastic also detected in the air in Geneva
Greenpeace finds plastic fibers in a recent sample. With what health risks? A HUG doctor takes stock.
A 6 -meter high sculpture inspired by the famous “thinker” of Rodin, created specially for the negotiations of the Plastics Treaty, on the Place des Nations in Geneva.
KEYSTONE
- The samples taken from Greenpeace last July reveal twelve plastic particles in 1.7 cubic meters of filtered air.
- The sample is limited to revealing the fragments of more than 10 microns, without diving into the concentration of nanoparticles.
- Ivan Guerreiro, pulmonologist at the HUG, explains that the deleterious effect on respiratory health was mainly studied in the context of professional and laboratory exhibitions. There is an important need for studies on the effects of inhalation in the population in general.
The metropolis at the end of Lake Geneva will be, until the end of the week, The world plastic capital. Difficult negotiations are held there in the United Nations in an attempt to bring out a treaty to limit plastic pollution worldwide.
The rest of the year, Geneva is not to be outdone. Measures carried out by Greenpeacein July, reveal the presence of microplastics in the ambient air. The one breathed in the 1900 participants in this UN Last Chance Conference.
These samples point to an unknown aspect of the problem of plastic particles, identified for twenty years – both on the Himalayan summits and in the body of many species of the depths. Their health effects are the subject of much research. “This study shows that the fragments and fibers of microplastics are an atmospheric pollutant in urban areas, even in Switzerland,” warns the environmental organization.
In July 2022, an exhibition in the courtyard of the Musée du Léman, in Nyon, already drew public attention to microplastics in the waters of Lake Geneva. Three years later, samples taken by Greenpeace in Geneva confirm their presence in the air that we breathe.
Chantal Dervey
Polyamide fibers
Bus interior, cafes, restaurants, shopping centers, workspaces … This instant photo was taken on July 17, aspiring 1.7 m³ of air for eight hours – just under half of what we breathe over this duration. Among the hundred micropossers chosen, most often “indeterminate”, the study under the microscope of its filtration “shows the presence of microplastics in quantities comparable to those of other studies – with six fragments and six fibers detected”, note the two researchers responsible for the analysis.
The identified plastics are proven to be polyester and polyamide fibers “which can come from clothing or furnishings”. As well as fragments made up of several types of polyethylene, for example those used in cables.
On July 17, 2025, a Greenpeace researcher spent the day sampling ambient air inside public spaces – public transport, cafes, restaurants, shopping centers, shops – as well as coworking spaces, to allow the measurement of their microfragment and plastic fibers.
© Marc Meier / Greenpeace
What about nanoparticles?
“We cannot assume that all the microplastics of the sample are inhaled, some can also be expired,” recognize the two researchers. Who also admit that “this snapshot does not allow us to draw from the plastic contamination of Geneva as a whole, or comparisons with other cities”. Even if, at first glance, the content observed seems far from the thousand microplastics identified per cubic meter in a study carried out in the Chinese metropolis of Wenzhou, in 2021.
However, the analysis of the Geneva sample was limited to the fragments of more than 10 microns. While recent studies make it possible to estimate an exhibition “100 times higher” at the microparticles of a few microns – the thickness of a soap bubble -, according to the researchers.
Still too few studies
What are the health effects of these air fragments? Ivan Guerreiro, assistant doctor at the Hug pulmonology service, replied that exposure to micro- and nanoplastics (MNP) in the professional framework was studied in the 1970s. The first highlighting of plastic in pulmonary tissue dates back to 1998. “On the other hand, there are very few studies on the general population and therefore on the impact of these inhaled pollutants on respiratory diseases and health.”
Ivan Guerreiro, assistant doctor at the Hug pulmonology service.
DR
A WHO report believes that human exposure via inhalation could be more than 3000 particles per day. However, Ivan Guerreiro recalls a principle: “The lung is designed to receive only air and dust. He also has defense mechanisms against microbes. Everything else can cause inflammation and cellular damage, sometimes irreversible. ”
Under these conditions, it would be “difficult to say that microplastics, whose inhaled quantity we probably underestimate, have no impact on our respiratory health”. Laboratory tests have shown that exposure to MNPs damages the cells of the lungs, in particular, the famous stem cells.
And the particles under 10 microns?
According to the doctor, one can imagine that these products promote the appearance or worsening of conventional respiratory diseases, such as fibrosis, COPD (chronic obstructive bronchopneumopathy) or pulmonary cancers. But he is cautious because many questions remain open.
Ivan Guerreiro also notes that the majority of studies evaluating the microplastics contained in the air highlight mainly sizes greater than 100 microns – which probably decreases their toxicity. Indeed, it is admitted that the inhaled particles must usually be of size less than 10 microns to reach the lung in depth.
In addition, the direct relationship between these particles present in the air that we breathe and precise pathologies is not scientifically established. “Contrary to what we know about conventional air pollution, there is, for example, no study which shows a link between the decline of pulmonary capacity and exposure to micro- and nanoplastics,” he explains.
More microplastics in tumors
The evidence is greater during specific professional exhibitions, with many cases described. Thus, a study was carried out in 1998 on exposure to plastics linked to work in PVC production. She has shown that plastic particle concentrations are higher in pulmonary tumors than in the adjacent lung. But apart from the professional context, knowledge is essentially based on studies carried out on animals or carried out in vitro.
Ivan Guerreiro still stresses that several sources of pollution can interact, and that it is difficult to differentiate the impact of each. Human is often exposed at the same time to microplastics and other products that can promote inflammation or carcinogenic additives (which can cause cancer). Finally, the effects vary according to the type of plastic studied, sometimes with differences between the results obtained in the laboratory and the real effects “in real life”.
“Latest news”
Do you want to stay at the top of the info? “24 hours” offers you two meetings a day, not to miss anything of what is happening in your canton, in Switzerland or in the world.
Other newsletters
Did you find an error? Please report it to us.