Annual average concentration of nitrogen dioxide is again above the legal limits. After validation of the data, ZERO will file a complaint to the European Commission for lack of measures to improve air quality.

The data for 2022, which is still provisional, shows that the nitrogen dioxide (NO2) on Avenida da Liberdade showed an annual average of 45 µg/m3 (microgram per cubic meter), a concentration about 12.5% higher than the maximum value of 40 µg/m3 required in the national legislation and European. And for two days last year an average concentration of 200 µg/m was exceeded.3. The environmental association ZERO will now request validation of the data and then will report non-compliance to the European Commission.
In a statement, ZERO explains that it has been following the evolution of air quality in Lisbon in detail. The association analyzes the concentration of pollutants measured at the air quality monitoring stations managed by the Lisbon and Tagus Valley (LVT) Regional Coordination and Development Commissions (CCDRs), and whose data is made available by the Portuguese Environment Agency.
No measures to improve air quality
In accordance with European legislation, when limits are exceeded, the responsible authorities should develop plans and programs to improve air qualityin order to reduce the concentrations of pollutants to the permitted level.
Between 2011 and 2014, there were several instances of non-compliance with the limit values for the pollutants nitrogen dioxide and particulate PM10 (these particles, with a diameter of less than 10 micrometers, can be inhaled and pose a considerable health risk as they penetrate deep into the body through the pulmonary alveoli). As a result, a plan to improve air quality in the Lisbon Metropolitan AreaThis plan was drawn up by the CCDR-LVT. In accordance with national legislation, these plans should form the basis for drawing up implementation programs, which should include the actions to be carried out, their timetable, as well as the identification of the entities responsible for their implementation and the indicators for assessing their effectiveness. However, ZERO denounces that, almost four years after the plan was drawn up, its implementation program it hasn't even been approved yet.
"One of main causes of air pollution in urban centers are the combustion gases resulting from road transport by car. Therefore, pollution can be counteracted by strong investments in public transport and soft mobility, as well as measures to reduce the use of individual transport - an advantage not only in terms of air quality, but also for people's wallets, the climate and improving public space in the city.", points to ZERO.
"However, in the Lisbon Metropolitan Area, car use has increased in the last decade, being the main means of transportation for most people, with a higher representation than public transport, walking and cycling all combined (Census 2021). O traffic already exceeds 2019 levels (TomTom Index), putting car traffic at chaotic levels. That's why ZERO warns of the urgent need for a Sustainable Urban Mobility Plan for the city of LisbonThis is the only capital in the southern European countries without a plan of this kind"the association also points out.
New European legislation will be more demanding and Portugal is unprepared
ZERO warns that, in the context of the ongoing review of current European air quality legislation, the annual limit value for nitrogen dioxide should be 20 µg/m3 and is expected to be exceeded not only on Avenida da Liberdade, but in many other places in Lisbon and throughout the country. The same will happen for other pollutants if no action is taken, the association says.
A air pollution is one of the main causes of premature death worldwideIt is responsible for around one in eight deaths. It is a threat to both human health and natural ecosystems, and is linked to the onset or worsening of diseases such as strokes, heart disease, lung cancer, and respiratory diseases such as asthma.
In the case of nitrogen dioxidein high concentrations has effects ranging from irritating the eyes and throat to affecting the respiratory tract, causing reduced breathing capacity, chest pains, pulmonary edema and damage to the central nervous system and tissues. Groups such as children, the elderly, asthmatics and people with chronic bronchitis are the most affected. This pollutant can also increase reactions to allergens of natural origin. In Portugal, air pollution is responsible for the premature death of around six thousand people every year.
The Lisbon Chamber put and kept the ambitious ZER ABC plan on the back burner, which proposed reduce car traffic by 40% in Lisbon's historic center. At the same time, the municipality has also failed to update the boundaries of the city's two existing ZERs. And in 2022, the Mayor, Carlos Moedas, criticized the approval by a majority of the city council of a proposal by Livre to hold car-free Sundays on that avenue - a measure which would contribute to reducing pollution on that artery at least once a week.