Interview. Pollution: "ZFEs arrived without the measures that were supposed to accompany them."

Charlotte Liotta, researcher in environmental economics at the Autonomous University of Barcelona.

Do Low Emission Zones (LEZs) work?

The main objective is to improve air quality. From this perspective, the measure is justified. Studies conducted in Europe, where there is a little more perspective than in France, show a reduction in air pollution (nitrogen dioxide and fine particles) when ZFEs are implemented.

In Madrid, for example, it has reduced the concentration of nitrogen dioxide, a gas harmful to health, by a third. In Germany, EPZs have helped reduce the incidence of respiratory and cardiovascular diseases.

The measure is criticized for its socially unequal aspect...

There are two dimensions to consider. There are beneficiaries: residents in the ZFE breathe better air. Their sociology depends on the shape of the city, which population lives where in the cities, etc.

For example, in Paris, it's mostly the wealthiest who live in the city center, but in Brussels, it's the opposite; it's mostly the lower-income population. But there are also the losers in the ZFE, in terms of accessibility and mobility.

Overall, it's the poorest who suffer, as they tend to own older, more polluting vehicles and live further from public transportation or their workplace. Our research has shown that employees and workers are the most affected by a loss of access to employment due to EPZs.

How can things be improved?

ZFEs are short-term policy decisions, targeting a specific vehicle type overnight. They are easier to implement than long-term public policies, such as improving the public transport network or providing social housing close to jobs.

But the ZFEs arrived without the measures that were initially supposed to accompany them: improving public transport (particularly the metropolitan RER), developing cycling, improving housing accessibility, etc. Yet a broader set of solutions is needed than the ZFEs. And this wasn't thought through. They were banned without providing sufficient support.

What are the problems encountered with the implementation of ZFE?

Already, ZFEs are much less unpopular than we think: studies show that a majority of citizens support them. We still have a problem with information and communication around ZFEs. People don't know what they are, where to get information, where to change vehicles, etc.

The benefits are also not well known, especially since it's about air quality: it's abstract, we don't realize it. Yet it's a major cause of mortality, with 47,000 premature deaths per year.