Researchers have for the first time analyzed outdoor particulate matter at Milano Linate Airport and identified high concentrations of benzothiazoles (BTHs), chemical additives from tire wear. The concentrations were significantly higher than those found in heavily trafficked Italian cities, with specific markers linked directly to airport operations. This study, published in Environmental Chemistry and Ecotoxicology, addresses a critical gap in understanding airport pollution beyond exhaust emissions.
Airports generate non-exhaust emissions, particularly tire wear particles (TWPs), which are produced during high-speed, high-friction events like takeoffs and landings. These rubber particles enter the atmosphere as particulate matter (PM), carrying chemical additives into the environment. "Although TWPs can derive from all tire-equipped vehicles, they might pose a higher risk at airports considering the large amount produced especially during the landings and the take offs," said Prof. Andrea Gambaro, senior author of the study available at https://doi.org/10.1016/j.enceco.2025.11.011.
The international research team investigated the chemical composition of atmospheric PM10 at Milano Linate Airport, focusing on eight rubber tire-related chemical markers and twenty-three other chemical species. They discovered BTH concentrations in airport PM10 were much higher than in other Italian cities like Milano and Collegno (Torino), indicating significant environmental input from airport activities.
By analyzing the sampling location and cross-referencing results with wind direction data, researchers discriminated between pollution sources. "This way, we discovered that the airport emits especially four benzothiazoles, two of which demonstrated a strong correlation among each other," explained lead author Dr. Giovanna Mazzi. Notably, these same compounds did not show this correlation in urban PM10 from other Northern Italian cities, suggesting they are specifically linked to airport operations.
An ecotoxicological assessment indicated low potential risk of occupational exposure to BTHs in outdoor air at Linate Airport. However, the identification of specific chemical markers represents significant progress in tracing airport non-exhaust emissions. "Although further research is still needed, these findings represent a key step toward identifying specific chemical markers for tracing airport non-exhaust emissions into the air," Mazzi added.
The research was developed within projects funded by Next Generation EU, including the "GRINS - Growing Resilient, INclusive and Sustainable" project and supported by the Department of Excellence 2023–2027 program. The work benefited from infrastructural support through the Italian Integrated Environmental Research Infrastructures System, funded by EU – Next Generation EU. This study matters because it reveals a previously understudied aspect of airport pollution that affects air quality near aviation facilities worldwide, providing crucial data for environmental monitoring and regulatory considerations.
