Antwerp is the most populous municipality in Belgium with a population of 530.504 and a metropolitan population of around 1.200.000 people, it is the second-largest metropolitan region in Belgium, after only Brussels. The Port of Antwerp is one of the largest in Europe and it has Europe's largest chemical cluster.
The City of Antwerp is working on better air quality. Air pollution by soot, particulate matter and nitrogen dioxide (NO2) must decrease further. The pollution is mainly the result of emissions from vehicles, companies and households. The city is tackling the problem in several ways, among them is a low emission zone.