Researchers have for the first time analyzed outdoor particulate matter (PM10) from Milano Linate Airport and determined concentrations of Benzothiazoles (BTHs), chemical additives used in tire manufacturing. The study, published in Environmental Chemistry and Ecotoxicology, found that BTH levels at the airport were significantly higher than those measured in highly trafficked Italian cities such as Milano and Collegno, indicating a substantial contribution from airport activities to environmental contamination.
Non-exhaust emissions, particularly tire wear particles (TWPs), are generated during high-speed, high-friction events such as landings and takeoffs. These particles can carry rubber chemical additives into the air and contribute to atmospheric particulate matter. “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.
The international and multidisciplinary research team investigated PM10 samples collected at Linate Airport, focusing on eight BTH markers and 23 other chemical species. By cross-referencing results with wind direction data, the team could discriminate between contributions from roads and parking areas versus airport activities. Lead author Dr. Giovanna Mazzi explained, “This way, we discovered that the airport emits especially four benzothiazoles, two of which demonstrated a strong correlation among each other.” Notably, these two compounds did not show similar behavior in urban PM10 samples from other Northern Italian cities, suggesting they may be specific tracers of airport non-exhaust emissions.
An ecotoxicological assessment indicated 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.
The study was funded by the Next Generation EU project “GRINS - Growing Resilient, INclusive and Sustainable” and supported by the Department of Excellence 2023–2027 and the Centre for Trace Analysis (CeTrA) through the ITINERIS project. The full study is available at https://doi.org/10.1016/j.enceco.2025.11.011.
