Study Reveals High Concentrations of Tire-Related Chemicals in Airport Air Pollution

Researchers have for the first time analyzed outdoor particulate matter at Milano Linate Airport and identified elevated concentrations of benzothiazoles (BTHs), chemical additives from tire wear particles. The study, published in Environmental Chemistry and Ecotoxicology, found BTH levels much higher than those in heavily trafficked Italian cities like Milan and Collegno, indicating airports may be significant sources of these pollutants.

While aviation's exhaust emissions receive considerable attention, non-exhaust emissions like tire wear particles remain poorly studied. These particles are generated during high-speed, high-friction events such as landings and takeoffs, releasing rubber particles that carry chemical additives into the atmosphere. "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 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. By cross-referencing results with wind direction data, researchers distinguished between pollution from roads and parking areas versus airport-specific emissions. "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 pattern in airborne urban PM10 sampled in other Northern Italian cities, suggesting they are specifically linked to airport activities. The findings represent a key step toward identifying chemical markers for tracing airport non-exhaust emissions, addressing what researchers describe as a "huge knowledge gap" in understanding aviation's environmental impact beyond exhaust gases.

An ecotoxicological assessment conducted as part of the research indicated a low potential risk of occupational exposure to BTHs in outdoor air at Linate Airport. However, the identification of specific airport-linked chemical markers provides regulators and airport operators with new tools for monitoring and potentially mitigating this form of pollution. The research was supported by multiple European Union initiatives, including the GRINS project funded by Next Generation EU.

As global air travel continues to expand, understanding all sources of airport-related pollution becomes increasingly important for environmental protection and public health. This research provides the first concrete evidence that airports emit specific tire-related chemicals at concentrations exceeding urban traffic areas, establishing a foundation for future monitoring and regulation of non-exhaust emissions in the aviation sector.