Air quality readings by ‘citizen scientists’ are revealing a far worse picture than that acknowledged by officials, writes Iarina Ciceu. The campaign by Hungarian activists is an inspiration to us all.
Iarina Ciceu is a volunteer with the Hungarian Clean Air Action Group, a member of the European Environmental Bureau.
Data collected in Budapest by the Clean Air Action Group (CAAG) suggests that air pollution in the city is far more harmful than that recorded by official measuring stations.
The death rate from air pollution in Hungary is said to be the second highest in the world, coming just behind China: about 10,000 people die prematurely in the country each year because of diseases linked to poor air quality.
While official data already demonstrates that the concentrations of certain harmful substances in Budapest’s air regularly exceed air quality limit values, our measurements highlight a further problem ignored by officials: ultrafine particulate matter (UFPs).
With a diameter smaller than 100 nanometres, these particles are especially dangerous and particularly hard to measure.
Although Budapest’s air can contain a very large number of UFPs, their mass is so vanishingly small that official figures, which assess air pollution by measuring the mass of pollutants contained in one cubic metre, do not capture the magnitude of the problem.
We have been monitoring concentrations of UFPs in Budapest since 2015, but have recently acquired a new device that has enabled more accurate measurements over the last four months. The new instrument can measure the number of particles with diameters between 10 and 700 nanometres in one cubic centimetre.
According to measurements to date, in environments with relatively clean urban air, the typical number of UFPs is around 3,000 per cubic centimetre, while on busy Budapest roads this figure is usually 30,000 to 60,000 – ten to twenty times higher. In one case it even rose as high as 470,000. The new device also shows the average diameter of the particles measured, a feat beyond the capabilities of our previous device. Along busy roads, average particle diameter ranged between 40 and 60 nanometres. The mass of these particles’ is so small that even a concentration of 500,000 particles per cubic centimetre would not result in a breach of air quality limit values in an official measuring station.
These measurements are particularly frightening because the smaller the pollutant particles, the more wide-ranging are their health effects.
While PM10 (less than 10,000 nanometres in diameter) and PM2.5 (less than 2,500 nanometres in diameter) particles only penetrate the lungs as far as the bronchi or bronchioles, UFPs can enter deeper into the alveoli; they are more prone to deposit in the lungs and can cause inflammation in the alveoli and exacerbation of existing respiratory diseases in more vulnerable individuals such as asthmatics, children, and those suffering from circulatory or respiratory diseases. More importantly, via the alveoli these particles can also enter the bloodstream and lead to cardiac arrhythmias, narrowing of blood vessels and enhanced coagulability, thereby increasing the number of cardiovascular disease-related deaths. Once in the bloodstream, UFPs can reach other organs as well. Research has shown that UFPs transported in the blood are primarily deposited in the liver, where they may cause oxidative stress which can damage cells and eventually lead to liver cirrhosis or even cancer.
Depending on their composition, ultrafine particles can also damage the brain. While airborne magnetite particles in the brain may increase the risk of Alzheimer’s disease, some carcinogenic particles are associated with an increased risk of brain cancer.
Another study has shown that UFPs can even infiltrate the placenta of pregnant women and harm the foetus.
Collecting evidence about the amount of ultrafine particles we breathe is key to adopt adequate measures to cut air pollution and protect our health and environment. The CAAG is ready to assist local authorities to ensure that UFPs monitoring becomes a priority.