Data for a new study, developed by researchers from the Centers for Research and Studies in Sociology (CIES-Iscte), Research in Information Sciences, Technologies and Architecture (ISTAR-IUL) and Natural Resources and Environment (CERENA), were collected by 80 sensors, between August 2021 and July this year.

In a note from the authors, it is explained that analysis of the values ​​of nitrogen dioxide (N02) and PM10 suspended particles was carried out, concluding that, in certain areas of the city of Lisbon, they “exceed the parameters accepted” by the WHO.

“The cruise terminal in Santa Apolónia, as well as the bike paths in certain arteries of the capital, are areas with high levels of pollution and harmful to health. The ongoing investigation corroborates, following previous studies, high traffic and maritime transport as determining factors in the pollution situations recorded in the municipality of Lisbon.

With regard to nitrogen dioxide, the researchers found that, in the period under analysis, the values ​​in the city of Lisbon were, on average, 71.08 μg/m3, “well above the level defined by the WHO”, which is 10 μg/m3.

Calçada de Carriche (Lumiar), Alameda da Encarnação, Avenida 24 de Julho, and Avenida Infante Dom Henrique, in Santa Apolónia, were the areas with the highest levels of nitrogen dioxide pollution.

With regard to the concentration of PM10 suspended particles, the most worrying levels were detected in Calçada da Ajuda, Rua dos Sapadores (Graça), Avenida Fontes Pereira de Melo, Avenida Alfredo Doutor Bensaúde (Olivais) and Calçada de Carriche.

For PM10 particles, the WHO sets the average daily limit at 45 ug/m3 and the average annual limit at 15 ug/m3.

“Although in none of the sensors used the average daily limit was exceeded on more than 10% of the days, the average annual value was 15.7 μg/m3, slightly exceeding the limit defined by the WHO”, explain the researchers.

According to the study's conclusions, transit and maritime transport are identified as possible causes for pollution levels to exceed the parameters established by the WHO.

In addition to these factors, the study also points to issues such as residential and commercial heating, construction, and industry as polluting elements, in addition to “natural phenomena such as the transport of dust from the Sahara desert”.

According to the authors of this study, the WHO states that “exposure to nitrogen dioxide and PM10 particles increases the risk of chronic diseases, such as acute respiratory infections, cardiovascular diseases, chronic obstructive pulmonary disease, and lung cancer.