Air Pollution In Belgium: Causes And Concerns

Belgium has been ranked poorly in terms of air quality, with numerous studies showing associations between fine particulate air pollutants and mortality in adults and infants. The country's air pollution is largely caused by emissions from diesel cars, which are substantially higher during real driving conditions than what is permitted by European legislation. Nitrogen oxides, released primarily by the burning of fossil fuels in traffic, are a major contributor to the country's air pollution, with concentrations of nitrogen dioxide (NO2) exceeding European and World Health Organization limits.

Nitrogen emissions from diesel cars

Belgium has been ranked poorly in the Environmental Performance Index (EPI) for air quality, finishing last among European countries in 2016. The country's air quality has been significantly impacted by nitrogen emissions, with certain areas recording some of the largest numbers of new asthma patients due to nitrogen dioxide. Nitrogen oxides are primarily released when fossil fuels are burned, and diesel cars are a major contributor to this issue.

Diesel cars have long been favoured in Belgium for their fiscal advantages and economic benefits. However, it is now recognized that they emit more dangerous pollutants than gasoline-powered cars. The combustion of fossil fuels in the transport sector, particularly by diesel vehicles, has led to a deterioration of urban air quality along city roads and highways.

Nitrogen oxides (NOx) emissions from diesel cars are a significant concern. These emissions are substantially higher during real driving conditions compared to the limits set by European legislation (EURO standards). Studies have shown that diesel cars have NOx emission rates ranging from 0.31 to 1.1 g/km, with some older models emitting even higher levels. In comparison, petrol cars have much lower NOx emission rates, with Euro 3-5 petrol cars emitting 5-10 times less.

The impact of nitrogen emissions from diesel cars on health cannot be overstated. In addition to asthma, high levels of nitrogen dioxide have been linked to an increased risk of respiratory disorders, decreased respiratory capacity, and the development of bronchitis. Air pollution peaks have also been associated with a significant increase in the number of heart attacks, and children are especially vulnerable to these health effects.

To address this issue, the Brussels-Capital Region has implemented a Low Emission Zone (LEZ) since 2018, gradually banning the most polluting vehicles, including old diesel cars. The timetable includes a phase-out of diesel cars by 2030, with the aim of significantly reducing emissions of nitrogen dioxide and other harmful pollutants. These measures are expected to have significant health benefits for residents, improving the air quality and reducing the negative impact of nitrogen emissions from diesel cars.

High volume of traffic

Belgium's air quality has been a significant concern, with the country scoring poorly on the Environmental Performance Index (EPI). While it is not the worst in Europe, Belgium's air pollution has a notable impact on the health of its residents, and traffic plays a major role in this issue.

The high volume of traffic in Belgium, particularly in densely populated areas, contributes significantly to air pollution. The country's dense population in certain regions, combined with a high number of vehicles on the roads, leads to a significant amount of pollutant emissions. These emissions are released primarily from the burning of fossil fuels, with diesel cars being a major contributor. Diesel-powered vehicles emit dangerous pollutants, including nitrogen oxides (NOx), which are known to have detrimental effects on human health.

Nitrogen oxides, particularly nitrogen dioxide (NO2), are of great concern in Belgium's air pollution crisis. Studies have linked the concentrations of NO2 in the air to the high number of new asthma patients under the age of 18 in the country. Belgium and the Netherlands record some of the highest numbers of new asthma cases attributed to NO2 pollution. This issue is exacerbated by the fact that diesel cars emit substantially higher levels of NOx during real driving conditions than what is permitted by European legislation.

The impact of traffic-related air pollution extends beyond respiratory disorders. Research has shown that air pollution peaks are associated with a significant increase in the number of heart attacks. Additionally, children are especially vulnerable to the effects of air pollution, with recent studies indicating potential impacts on cognitive development and an increased risk of premature birth and lower birth weight.

To address the issue of air pollution caused by traffic, Belgium has taken steps to improve its air quality. Since 2018, the most polluting vehicles have been gradually banned in the Brussels-Capital Region. The establishment of Low Emission Zones (LEZ) in Brussels aims to reduce emissions of harmful pollutants, particularly fine particles such as black carbon, and nitrogen oxides. These measures are expected to have a positive impact on the health of residents, demonstrating a commitment to mitigating the effects of traffic-related air pollution in the country.

High levels of PM2.5

Belgium has been ranked poorly in the Environmental Performance Index (EPI) regarding air quality, finishing last among European countries. The most dominant indicator causing Belgium's low air quality score is the "population-averaged spatial mean of PM2.5 concentrations" or average population exposure to PM2.5.

PM2.5 refers to particulate matter that is 2.5 microns or smaller in diameter. These fine particles can be inhaled deep into the respiratory system, causing or exacerbating a range of health issues. In Belgium, high levels of PM2.5 have been linked to increased infant mortality, with a 2011 study finding that the risk of death increased by 4% for a 10-µg/m³ increase in daily mean PM2.5. The association was even more significant for late neonates (2-4 weeks old), with an 11% increased risk of death per 10-µg/m³ increase.

Numerous studies have also found associations between fine particulate air pollutants and mortality in adults. Short-term effects of elevated PM2.5 levels have been studied in Flanders, Belgium, with results indicating a link to nontraumatic causes of death before one year of age. In addition, air pollution peaks have been associated with a significant increase in the number of heart attacks.

The sources of PM2.5 pollution in Belgium are varied. One significant contributor is nitrogen oxides (NOx) emissions, primarily from diesel cars. Certain areas with high traffic density, such as ring roads, highways, and inner-city streets, experience high NO2 concentrations. While Belgium has implemented measures like Low Emission Zones (LEZ) to reduce emissions, real-world driving conditions often result in higher emissions than what is allowed by European legislation.

Black carbon emissions

Black carbon, or black carbon soot, is a type of particulate matter (PM) that is released into the atmosphere as a result of the incomplete combustion of fossil fuels, biofuel, and biomass (such as wood). It is one of the key contributors to air pollution in Belgium, which has been linked to a range of adverse health effects, including respiratory disorders, decreased respiratory capacity, and the development of asthma and bronchitis.

In Belgium, black carbon emissions are primarily generated by diesel-powered vehicles, which are a significant source of air pollution in the country. Due to historical fiscal incentives and economic advantages, diesel cars have long been favoured in Belgium. However, it is now recognized that diesel vehicles emit more dangerous pollutants than gasoline-powered cars, particularly nitrogen oxides (NOx) and black carbon.

To address the issue of black carbon emissions and improve air quality, the Brussels-Capital Region has started to gradually ban the most polluting vehicles. The establishment of Low Emission Zones (LEZ) in Brussels aims to reduce emissions of harmful pollutants, including fine particles such as black carbon, and nitrogen oxides. By prohibiting access to the city for the most polluting vehicles, the LEZ is expected to have a positive impact on the health of Brussels residents, particularly children, who are especially vulnerable to the effects of air pollution.

While Belgium's overall air quality score remains relatively low compared to other European countries, efforts to reduce black carbon emissions and improve air quality are ongoing. The gradual phase-out of polluting vehicles, the implementation of emission reduction strategies, and the transition to cleaner energy sources are all contributing to a downward trend in Belgium's carbon dioxide emissions, with levels in 2023 being the lowest in over five decades.

Ozone (O3)

O3 concentration depends on weather conditions, season, time of day, and emissions of precursors. Typically, O3 levels are higher during the daytime and on sunny days. Over the year, O3 concentrations are higher in the summer, with the peak ozone season in Belgium ranging from April to September.

Ozone is a highly reactive and oxidative gas, which makes it harmful to both humans and ecosystems. High O3 concentrations have been linked to a range of respiratory problems, including coughing, wheezing, asthma attacks, and even death in extreme cases. Ozone affects individuals of all ages.

In Belgium, O3 concentrations are generally higher in the Walloon Region compared to the Flemish Region and the Brussels Capital Region. The spatial pattern of O3 is largely the inverse of the pattern of NO2, with locations of high NO2 concentrations, such as cities and busy roads, having lower O3 pollution.

Frequently asked questions