Qualité de l’air à Debrecen

What is the current level of air pollution in Debrecen?

Debrecen is Hungary's second-largest city, after Budapest, and is the regional centre of the Northern Great Plain region. According to a census conducted in 2019, the estimated population was calculated as 202,402 people, with approximately 328,642 when taking the entire urban area into account.

At the beginning of 2022, Debrecen was experiencing a period of “Moderate” air quality with a US AQI reading of 63. This United States Air Quality Index number is an internationally used set of metrics supported by the World Health Organisation (WHO) and is used to compare the air quality in different cities throughout the world using comparable standards. It is calculated by using the levels of the six most commonly found pollutants such as nitrogen dioxide, sulphur dioxide, ozone, carbon monoxide and both sizes of particulate matter, which are PM2.5 and PM10. If all six figures are not always available in which case, a level is calculated by using what data there is. Debrecen measured all six of these major pollutants which were as follows; PM2.5 - 18 µg/m³, PM10 - 19 µg/m³, ozone (O₃) - 58.1 µg/m³, nitrogen dioxide (NO₂) - 8.6 µg/m³, sulphur dioxide (SO₂) - 4 µg/m³ and carbon monoxide (CO) - 684 µg/m³.

This level of PM2.5 is almost twice the recommended safe level of 10 µg/m³ as suggested by the World Health Organisation (WHO) as being an acceptable level. Although no amount of air pollution is considered to be safe.

When air pollution is classified as being “Moderate” the given advice would be to remain indoors as much as possible, closing doors and windows to prevent the ingress of more polluted air. Those who are more sensitive to poor quality air should avoid venturing outside until it improves. If this is unavoidable, then a good quality face mask should be worn at all times. All types of outdoor exercise should be avoided until the air quality improves. There is a downloadable app from AirVisual.com which is suitable for all operating systems and gives the latest information regarding air quality in real-time.

Does the level of air pollution vary much throughout the year in Debrecen?

Air quality can be affected by many things, therefore it can and does change rapidly depending on the local conditions. Looking back at the 2020 figures published by IQAir.com, it can be seen that for the months of May, June and July, Debrecen achieved the target figure of being 10 µg/m³ or less as recommended by the WHO. The cleanest month was June with a figure of 8.3 µg/m³. The months of August and September saw “Good” air quality with readings between 10.1 and 12.0 µg/m³. The remaining seven months of the year saw air from the “Moderate” category with readings between 12.1 and 35.4 µg/m³. The dirtiest month was January with a figure of 34.7 µg/m³.

There were no records about air pollution kept before 2020 when a figure of 16.1 µg/m³ was recorded, however, this lower figure was almost expected because it would have been affected by the COVID-19 pandemic as many vehicles were no longer in daily use because the offices were closed and the staff encouraged to work from home, in an attempt to halt the spread of the virus. Many factories and non-essential production units were also required to close which removed their emissions from the atmosphere, albeit on a temporary basis. Worldwide, cities reported a much better quality of air due to the general lack of traffic pollution in city centres due to the pandemic.

Where does all the air pollution come from in Debrecen?

The winter smog situation is typically caused by high concentrations of nitrogen oxides and particles entering the air. Both are released into the air in large quantities during heating and road transport. Gas heating is responsible for nitrogen oxides, while coal and wood heating converts smog with soot and other hydrocarbon particles. Even more damaging than the latter is the unfortunate practice in many places of burning waste (especially plastics).

Incineration of garden waste is also a significant source of air pollution.

Nitrogen oxides are formed by heat. 78 per cent of the atmosphere consists of stable nitrogen gas, which is naturally oxidized during forest fires and nitrogen oxides. The same process takes place under human influence, for example when burning fossil fuel in cars, or in thermal power plants, or even in household-sized stoves and boilers.

Smoke from wood burning contains substances that are harmful to health due to imperfect combustion. Wood burning can also make a significant contribution to emissions of volatile organic compounds, carbon monoxide and some heavy metals.

Can anything be done to improve air quality in Debrecen?

There is a wide range of measures available to the state, authorities and municipalities that can reduce air pollution in the longer term. They can limit emissions by tightening regulations and raising penalties, and they can support the thermal insulation of buildings and the modernization of heating. They can reduce car traffic by city tolls, creating green zones and improving the conditions for public transport and cycling. Replacing obsolete buses is also urgent. Mileage-based tolls on trucks, for example, reduce emissions from one of the biggest polluters, truck traffic.

What are the detrimental effects of breathing in polluted air?

Sulphur dioxide has a detrimental effect on organisms, manifested in the fact that it combines with the moisture content of the atmosphere to form sulfuric acid and damages organisms, the soil and the built environment, and destroys plant tissue. It causes symptoms of intoxication with difficulty breathing in animals and humans, and is one of the causes of inflammatory disease of the mucous membranes. Cattle have been found to die due to respiratory lesions and to die due to acidification of the waters. Inflammation of the sinuses and bronchitis are common in people and emphysema, as well as sulphur dioxide irritates the mucous membranes, can lead to severe coughing, lung disorders, and even death.

Carbon monoxide (CO) is also a colourless, odourless, but extremely toxic, explosive gas that is the end product of the imperfect combustion of carbon and carbon-containing compounds. Just like soot. Inhaling small amounts over a long period of time can cause fatal poisoning, as inhaling a certain amount of carbon monoxide removes oxygen from the brain in an amount that causes the brain to shut down, ultimately due to persistent lack of oxygen. Its affinity for red blood cells is three hundred times greater than that of oxygen.