Archive for the 'Air Pollution' Category

Particulate Air Pollution

shanghai_china_skyline_111229_o Over the last decade there has been a clear lack of improvement in air quality and particulate matter concentrations.

Traffic is the main source of PM in urban areas.  Diesel exhausts are rich in ultrafine particles and contain a range of highly toxic substances.  Such particles are able to penetrate deep within the lungs into the alveolar region, where oxygen exchange occurs.  Over the last 25 years, the health effects have been uncovered by high-powered studies looking at particle concentrations and mortality.  It is thought that a 7-8 month loss in life expectancy can be attributed to air pollution, and this has been compared to a 2-3 month loss per person for both second hand smoking and car accidents.  The health effects on individuals will vary according to different exposures and susceptibilities.

Indicators of road traffic emissions show a lack of any sustained improvements since 2002 and a recent air quality study ranking European cities according to how well they tackled particulate air pollution between 2005 and 2010 shows that London is not far from the bottom.   This appears likely to be due to increasing traffic volumes as well as less than expected emission reductions from the introduction of new vehicle emissions standards, which suggests a discrepancy between test cycles and real world driving conditions.  A lack of political will means that significant air quality improvements for UK urban areas are unlikely anytime soon.