A new study published in Environmental Chemistry and Ecotoxicology provides the first analysis of outdoor PM10 at Milano Linate Airport, revealing elevated levels of benzothiazoles (BTHs)—chemical additives from tire wear. The findings underscore the significant but often overlooked contribution of airports to non-exhaust particulate pollution, with implications for air quality monitoring and occupational health.
The aviation sector is a vital global connector, but airports generate forms of pollution beyond exhaust emissions. Tire wear particles (TWPs) are produced during high-speed, high-friction events like landings and takeoffs. These rubber particles can carry chemical additives into the atmosphere, contributing to particulate matter (PM). Despite this, airport non-exhaust emissions remain poorly studied.
Professor Andrea Gambaro, senior author of the study, noted, "Although TWPs can derive from all tire-equipped vehicles, they might pose a higher risk at airports considering the large amount produced especially during landings and takeoffs." The research team, part of an international and multidisciplinary collaboration, analyzed the chemical composition of PM10 at Linate, focusing on eight BTHs and 23 other chemical species to identify tracers linked to airport activities.
The study discovered that BTH concentrations in airport PM10 were much higher than in heavily trafficked Italian cities such as Milan and Collegno (Turin), highlighting the substantial input from airport operations. Further insights emerged when considering wind direction data. The sampling site was influenced by two sources: roads and parking on one side, and airport activities on the other. By cross-referencing results with wind data, lead author Dr. Giovanna Mazzi and her team discriminated the contributions. They found that the airport emits four specific benzothiazoles, two of which showed a strong correlation—a behavior not observed in urban PM10 from other northern Italian cities, suggesting their link to airport activities.
An ecotoxicological assessment indicated a low potential risk of occupational exposure to BTHs in outdoor air at Linate. However, the researchers emphasize that further studies are needed.
"These findings represent a key step toward identifying specific chemical markers for tracing airport non-exhaust emissions into the air," Mazzi added. The study, funded by the Next Generation EU project "GRINS" and other sources, provides critical baseline data for future air quality management and regulatory efforts.
For more details, the study is available at https://doi.org/10.1016/j.enceco.2025.11.011. The research was supported by the Department of Excellence 2023–2027 and the ITINERIS infrastructure project.
