Filters fitted to vehicle exhaust systems to remove particulate matter pollution have limited impact on ultrafine particles, new research shows.
Filters fitted to vehicle exhaust systems to remove particulate matter pollution have limited impact on ultrafine particles, new research shows.
Airborne particles from vehicle emissions are a major contributor to air pollution levels. Exhaust filters designed to mitigate this pollution have been a legal requirement in new cars since 2011, and in heavy duty vehicles since 2013.
The filters are able to remove the majority of larger, solid particles, but the new study, published in Environment International, shows they are less effective at removing smaller liquid particles.
While the World Health Organization has not yet set a guideline for safe levels of ultrafine particles, it recognizes that particulate pollution overall is associated with negative impacts on cardiovascular and respiratory health.
