Air pollution is a real public health issue. With more than 40,000 deaths per year attributed to poor air quality, according to French authorities, it is even a national problem. Fine particles, microparticles, nanoparticles, dust, droplets... How do you find your way around? Where do they come from and what are the dangers? Finally, how do we measure them and how can we protect ourselves from fine particles? Are anti-pollution masks really efficient?
What are fine particles?
Fine particles are a category of solid or liquid airborn particles, with a diameter of less than 2.5 microns (µm). Within this category called PM for Particulate Matter, we mainly distinguish PM10, PM2.5 andPM1 with a diameter of less than 1µm called ultrafine particles up to PM0.1 ie nanoparticles less than 0.1µm. To put it simply, we could say that these are extremely fine dusts.
Where do those fine particles come from?
They can be of natural origin like volcanic eruption, land fires, atmospheric chemical reaction, natural particles carried by the wind such as pollen, mold in homes, bacteria and viruses. But main of this dust link to human activities comes from combustion that is not complete and which generates what is called unburned matter.
When we see smoke coming out of a chimney pot, an exhaust pipe or when we breathe out cigarette smoke, it is because there are, in addition to water vapour, a lot of more or less small size particles. Industrial activity, road traffic (exhaust gases, brake pad dust, tyre wear, road wear, etc.), heating (wood, coal, fuel), solvents used in glues, furniture or household products are all sources producing toxic fine particles.
The most dangerous are sulfur dioxide, ozone, carbon monoxide and nitrogen dioxide.
What are the dangers to humans?
We need to breathe 15,000 liters of air per day to provide our bodies with the oxygen they need. This exposure makes air the main threat to our lungs when it is polluted.
Unlike heavier dust that falls to the ground, fine particles remain suspended in the air as aerosols. This is why they are very likely to infiltrate the respiratory tract. Depending on their quantity and toxicity, these colorless and odorless enemies can cause health problems for those who breathe them, from simple irritation to cardiovascular accidents, chronic respiratory diseases, degradation of the body's defenses to microbial infections, diabetes or lung cancer.
According to WHO (Risk Assessment Summary, 2005 update), more than 2 million premature deaths worldwide each year can be attributed to the effects of outdoor air pollution in cities and indoor air pollution.
Source: International Institute for Applied Systems Analysis
How are fine particles measured?
Pollution is measured in micrograms per cubic meter of air and depending on the type of particles, a maximum number of days exposed to them should not be exceeded. The WHO (World Health Organization) recommends exposure levels (concentrations and durations) below which no harmful effects on human health have been observed.
The Air Quality Index (AQI) is calculated by taking into account measurements of the six main pollutants. PM2.5 is the smallest particle measured. The waqi.info website allows you to know the AQI in real time anywhere in the world (well, where there are sensors). There are a multitude of applications for monitoring air quality
Maps have been available for several years on an annual scale and every day for the previous day. They are now available on an hourly scale, in real time.
How to protect from fine particles?
Many studies show that protection against fine particles such as caulking is not 100% effective because they infiltrate everywhere. The only effective option is to reduce their emissions as an integral part of the ecological transition (CSR approaches for companies, development of soft mobility, use of electric vehicles, development of non-polluting public transport, speed limits, etc.).
It is possible to act to reduce indoor air pollution in homes, offices or cars by airing them by opening the windows wide, at least 10 minutes per day and during activities such as cleaning, DIY, cooking, etc. The aim of this natural ventilation is to dry the air and surfaces.
It is also important to ensure good ventilation of the home in order to renew the air continuously, whether natural (vents and grilles) or mechanical (controlled mechanical ventilation or CMV) and to maintain them regularly.
Outside, the best solution to protect yourself remains the use of a filter mask, especially when cycling or on 2 wheels in the middle of road traffic. It will also be necessary to ensure its filtration level (FFP2/N95 minimum) and its sealing so that a maximum of inspired air passes through the filters and not through the sides between the mask and the skin. It will therefore be important to know how to choose your respiratory mask.
Frogmask masks are equipped with FFP2/N95 filters, a standard that requires a minimum of 94% filtration of the inspired air for particles up to 0.4µm. Available in 3 sizes so that the mask is well adapted to the morphology of the face and ensures a good seal. Very breathable and limiting fogging thanks to the double noseband system (mask and filter), they are suitable for both occasional and intensive use.
