Diesel pollution sky-high in Brussels

29 November 2021

A new study shows that diesel vehicles and filter malfunctions account for shocking amounts of air pollutants in the Brussels-Capital Region, confirming the need to gradually eliminate diesel transport in the city.

The research found that although only 12% of diesel Euro 4 cars were tested, they produced almost half of all emissions of particulate matter (PM) measured.

Diesel Euro 5 – just 20% of all cars sampled – were responsible for 40% of the total release of nitrogen oxides (NOx) in the air. Faults to particulate filters detected in 5% of the light-duty diesel vehicles fitted with it caused over 90% of particle number (PN) emissions in total.

In general, diesel Euro 4, Euro 5 and Euro 6 showed NOx emissions from three to five times above legal limits. Conversely, the newest diesel models belonging to categories Euro 6d-TEMP and Euro 6d released the lowest amount of NOx compared to all other diesel vehicles.

Vehicles in Brussels’ city centre. Photo by: ssalae

The region steps in

The report validates existing plans to ban older diesel cars from the Belgian capital’s roads as a crucial measure to lower pollution levels, says Alain Maron, Environment Minister of the Brussels-Capital Region.

“It proves that Euro 4 and Euro 5 vehicles, which will be affected by the next milestones of our Low Emission Zone, have a disproportionate impact on air quality in Brussels, and that phasing them out will have a significant positive impact on air pollution,” Maron explains.

To limit the effects of private transport on human health and the environment, in 2018 the Brussels-Capital Region set up a Low Emissions Zone to outlaw the most polluting vehicles and eventually all fossil fuel-powered cars by 2035. This while making efforts to widen the city’s cycling infrastructure and encourage the use of public transport.

The region plans to ban Euro 4 transport from 2022, diesel Euro 5 from 2025 and to put an end to diesel particulate filter fraud. “In 2022, Brussels will become a pioneer in Europe by introducing new exhaust tests capable of detecting such problem, during the annual technical inspection of all vehicles,” Maron explains.

The Brussels study reviewed 130,588 cars in total and relied on sensors and light beams placed along roads in eight areas of the city between October and December 2020. The study was carried out by Bruxelles Environnement – the region’s environmental agency – and the International Council for Clean Transportation, within the framework of The Real Urban Emissions Initiative (TRUE) campaign.

Cars in Brussels. Photo by: Satyam Kapoor

A Europe-wide issue

The “Evaluation of real-world vehicle emissions in Brussels” report comes as the European Commission is expected to propose a revision of current EU vehicle emission standards legislation – so-called Euro 7/VII – in the coming months.

This latest data was published just a few months after the WHO issued new Air Quality Guidelines recommending much lower limits than those in place in the EU and demanding more decisive action.

The Belgian study provides just a snapshot of the complex air quality picture in Europe. Although municipalities – from London to Florence to Sofia – are taking decisive action, the continent is still struggling to meet recommended standards, with heavy consequences on residents’ health.

Air pollution poses the biggest environmental health threat in Europe, according to the European Environmental Agency. It is the continent’s major cause of premature death and is linked to illnesses such as heart and lung disease, stroke and lung cancer. It also leads to biodiversity loss.

While the risk of certain diseases can be lessened by abstaining from smoking, drinking, undergoing check-ups or exercising, pollution is inescapable so the most effective way to prevent air quality-related illnesses is to reduce transport emissions.

Will Euro 7 help clear the air?

The EU’s planned shift to zero-emission mobility will eventually help, but combustion engine vehicles will continue to be sold until their proposed phase out in 2035 and stay on the roads much beyond that.

The issue calls for an urgent review of current rules. The EU Commission’s Euro 7 new regulation may help provide answers and carve a new direction.

To shed light on some of the key issues of Euro 7, on 3 December Eurocities will moderate an online debate among cities, EU officials, representatives from Transport and Environment and BEUC, the European Consumer Organisation .

What: Euro 7 – Updating the EU’s vehicle emission standards: what’s at stake? Why it matters?
When: Friday 3 December 2021, 13:00 – 14:00 CET
Where: online. Click here to register and find the full agenda.




Daniela Berretta Eurocities Writer