The aviation sector plays a key role in worldwide connections, yet alongside its benefits, airports generate forms of pollution, beyond exhaust gas emissions, that are often underestimated and go unnoticed: non-exhaust emissions, such as tire wear particles (TWPs). Produced during the high-speed, high-friction events, TWPs are rubber particles that can easily enter the air, contributing to the atmospheric Particulate Matter (PM), and affect its quality by also carrying rubber 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 a new study published in Environmental Chemistry and Ecotoxicology. "So far, airport non-exhaust emissions are still poorly studied, leaving a huge knowledge gap."
The researchers, from an international and multidisciplinary context, investigated the chemical composition of atmospheric PM10 of Milano Linate Airport, with a focus on eight rubber tire-related chemical markers (Benzothiazoles, BTHs) and other twenty-three chemical species, aiming to find tracers specifically linked to airport activities.
The team discovered that BTHs' concentrations determined in outdoor airport PM10 was much higher than in other trafficked Italian cities such as Milano and Collegno (Torino), pointing out the significant input of these chemicals into the environment due to airport activities.
Additional insights were discovered when considering the location and the surroundings of the sampling spot. Indeed, the PM10 was sampled in an area influenced by two main sources of Benzothiazoles: roads and parking on the right-side, and airport activities on the left side.
"By cross-referencing our results with wind direction data, we managed to discriminate the contribution of the two sources" explained lead author Dr. Giovanna Mazzi. "This way, we discovered that the airport emits especially four benzothiazoles, two of which demonstrated a strong correlation among each other." Notably, the same compounds did not show this behaviour in airborne urban PM10 sampled in other cities of Northern Italy, highlighting that they might be linked to the airport activities.
An ecotoxicological assessment was also carried, which highlighted a low potential risk of occupational exposure to BTHs in outdoor air at Linate airport.
"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.
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References
DOI
10.1016/j.enceco.2025.11.011
Original Source URL
https://doi.org/10.1016/j.enceco.2025.11.011
Funding information
This article was developed within the project funded by Next Generation EU- "GRINS - Growing Resilient, INclusive and Sustainable" project (PE0000018), National Recovery and Resilience Plan (NRRP) PE9 Mission 4, C2, Intervention 1.3. The present work was supported within the framework of the Department of Excellence 2023–2027 (Ministero dell'Università e della Ricerca, AIS.DIP.ECCELLENZA2023_27.FF project). This work has benefited from the infrastructural support of the Centre for Trace Analysis (CeTrA) of Ca' Foscari University through the project IR0000032 – ITINERIS, Italian Integrated Environmental Research Infrastructures System, funded by EU – Next Generation EU, PNRR – Mission 4 "Education and Research" Component 2: "From research to business"–Investment 3.1: "Fund for the realization of an integrated system of research and innovation infrastructures".
About Environmental Chemistry and Ecotoxicology
Environmental Chemistry and Ecotoxicology publishes studies that examine the environmental chemistry (distribution, dynamics and fate) of pollutants, the biologic and toxic effects of man-made chemical pollutants on ecotoxicological animal models and plants.