Posted on 28 February 2017
Alastair Lewis, Professor of Atmospheric Chemistry at the National Centre for Atmospheric Science (WACL), responded to the report:
“The report highlights the considerable uncertainties that exist in trying to estimate concentrations of air pollutants 5, 10 and as far as 20 years out from today; the recent track record with forecasting NO2 does not help instil confidence. Whether the areas around Heathrow will meet current air quality standards will be crucially dependant on how emissions from other sectors evolve over time, and whether predicted reductions from these can offset new pollution arising from expansion. Part of this will depend on the uptake of newer low emissions cars, something highlighted in the report, but it will also depend on continued reductions in emissions from trucks, buses, and other numerous other combustion sources.
“The report focuses particular attention on whether statutory air quality targets will be met and these are a clear set of obligations that the government has to meet. This is a simple a pass / fail test - concentrations just above the limit value and it’s a fail, just below and it’s a pass. However the health impacts of air pollution do not conveniently follow a similarly simple set of pass / fail rules. Elevated air pollution even below limit values is now known to affect health and has a real cost. The ambition should always be for development to aim for as low a concentration of pollution as is practical, not simply to do the minimum necessary to gain a pass-mark.”