Reducing In-Cabin Exposure To Pollen Allergens- A Controlled Study of Cabin Filter Performance Against Key Asthma Triggers

JOHN MCKEON, John Ryan, Angela Southey, Oliver Dsa, Allergy Standards Ltd

     Abstract Number: 385
     Working Group: Exhibitor and Instrument Application Showcase

Abstract
Asthma remains a major global public health issue, with airborne pollen identified as a significant trigger, contributing heavily to disease burden worldwide. Among the wide range of aeroallergens, specific pollen-derived allergens—Phl p 5 (from timothy grass), Bet v 1 (from birch), and Amb a 1 (from ragweed)—stand out as leading agents in inducing allergic asthma symptoms. Amb a 1 alone accounts for over 99.9% of ragweed allergenicity. As urban populations spend considerable time traveling in enclosed motorized vehicles annually, in-cabin air quality has emerged as a critical factor in respiratory health. Despite the confined environment, insufficient attention is often paid to the air filtration systems within vehicles.

This study was bespoke designed to evaluate the efficacy of automotive cabin air filters in mitigating pollen exposure. A specialized test rig (plenum) was engineered to securely accommodate standard cabin filters, which was then integrated into a vehicle's air handling system. Controlled pollen aerosols—containing known concentrations of Phl p 5, Bet v 1, and Amb a 1—were introduced via the duct inlet to simulate real-world pollen infiltration. The downstream air was monitored to assess the filters’ pollen removal performance.

The results demonstrated high filtration efficiency: the cabin filter removed 99% of particles larger than 3 µm, and significantly reduced allergen concentrations—with a 99.8% reduction for Phl p 5, and over 99.9% reductions for both Bet v 1 and Amb a 1. Further testing is recommended to assess VOC removal efficiency. These findings underscore the critical role that correctly installed, high-efficiency cabin air filters can play in protecting vehicle occupants from allergenic pollen exposure, particularly for individuals with asthma or allergic rhinitis. Implementing and maintaining effective cabin filtration systems could be a practical intervention to mitigate the global burden of pollen-induced asthma symptoms.