Citizen study shows big differences in air pollution at street level


The CurieuzeNeuzen project in Antwerp has shown that air quality can differ significantly between neighbouring streets, depending on the amount of traffic

Curious noses

The air quality in cities differs significantly from street to street, according to a citizen project in Antwerp. The air in a small and busy street can contain twice as much nitrogen dioxide (NO2) as that in a traffic-free street, even if the roads are next to each other.

As part of the CurieuzeNeuzen (Curious Noses) project, which ran throughout May, 2,000 Antwerp citizens hung sensors in their window to measure the amount of NO2, an important indicator for air pollution caused by traffic. Scientists from Antwerp University and the Free University of Brussels (VUB) analysed the results, at the request of activist organisation Ringland.

The lowest NO2 concentrations were found in traffic-free areas like the city park, where they amounted to 30 micrograms of NOper cubic metre. This is still higher than outside the city centre. “The concentration in the centre is increased by local traffic and traffic on the ring road,” VUB researcher Joris Van den Bossche told science magazine Eos.

The highest concentrations, of about 60 micrograms, were measured in narrow streets with tall, continuous buildings on both sides of the road.

The European limit for NOis  set at an annual average of 40 micrograms. On the basis of the data, the scientists believe that this limit is exceeded at 45% of the measuring points used for CurieuzeNeuzen.

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