A study conducted by the University of Hertfordshire, published in the journal Atmospheric Environment, has concluded that nearly half of the air pollution from road traffic is down to non-exhaust sources such as brake-wear, road surface-wear, and particles launched into the air from the road by passing vehicles. The research team took samples from the Hatfield Tunnel on the A1 (M) in Hertfordshire which “provided an ideal laboratory” according to Professor Sokhi, who led the study, as it minimised the effect of the weather.
The study focussed on particulate matter with an aerodynamic diameter of less than 10µm (PM10) which is linked with long-term health problems such as heart disease. In the laboratory, samples were separated into their chemical components and their origins analysed. Results showed that petrol and diesel exhausts are responsible for only 33% of the particles, 27% are thrown into the air from the road by vehicles, while brake and road surface wear account for 11% each.
Road traffic is thought to be the most important source of air pollution in the UK. As well as the health effects, poor air quality is estimated to cost the UK economy up to £16 billion every year. As a result of the study, Professor Sokhi is calling for greater control of non-exhaust pollution stating that; “in terms of mass, non-exhaust sources can be more important than exhaust fumes, but legislative control has focussed on exhaust emissions. As exhaust regulations become stricter, non-exhaust sources become proportionately more important. Continuing to control exhaust emissions alone may not be enough to achieve legal air-quality standards.”
Across the UK and internationally, through the use of Air Quality Assessments, REC’s Air Quality Consultants work to ensure communities are not exposed to poor air quality, as a result of road traffic exhaust pollution. REC undertakes dispersion modelling assessments to help protect sensitive receptors such as schools, hospitals and residential areas from high pollution levels and associated health effects, and to ensure legal air quality standards are complied with.