Researchers have for the first time analyzed outdoor particulate matter at Milano Linate Airport and determined concentrations of benzothiazoles (BTHs), tire-related additives that show much higher levels than in heavily trafficked Italian cities. The study, published in Environmental Chemistry and Ecotoxicology, provides critical data on non-exhaust emissions from aviation activities, specifically tire wear particles generated during aircraft landings and takeoffs.
While the aviation sector enables global connectivity, airports generate forms of pollution beyond exhaust emissions that often go unnoticed. Tire wear particles are produced during high-speed, high-friction events and can easily enter the air, contributing to atmospheric particulate matter and 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 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 to identify tracers specifically linked to airport activities. They discovered BTH concentrations in outdoor airport PM10 were significantly higher than in other trafficked Italian cities like Milano and Collegno, highlighting the substantial environmental input from airport operations.
By cross-referencing results with wind direction data, researchers managed to discriminate between contributions from roads and parking areas versus airport activities. "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 behavior in airborne urban PM10 sampled in other Northern Italian cities, indicating they might be specifically linked to airport activities.
The ecotoxicological assessment showed a low potential risk of occupational exposure to BTHs in outdoor air at Linate Airport. However, the findings represent a crucial step toward identifying specific chemical markers for tracing airport non-exhaust emissions into the air. "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.
For business and technology leaders in the aviation and transportation sectors, this research highlights an emerging environmental consideration beyond traditional emissions metrics. The identification of airport-specific chemical markers creates new possibilities for monitoring and potentially regulating non-exhaust emissions, which could influence future airport operations, environmental compliance strategies, and sustainable aviation initiatives. As airports worldwide face increasing pressure to reduce their environmental footprint, understanding and addressing all emission sources becomes essential for long-term operational sustainability and regulatory compliance.
