July 26, 2017

expert reaction to the Government’s Air Quality Plan for nitrogen dioxide

New diesel and petrol vans and cars will be banned in the UK from 2040 in a bit to tackle the effect of poor air quality on people’s health, the government has announced.

Dr Zongbo Shi, air pollution scientist, University of Birmingham, said:

“The headlines today are ‘New diesel and petrol cars to be banned from 2040’, but this policy is not going to do any good to the current air pollution problems in the UK.  It is good to see that some new measures are being proposed to encourage the uptake of the cleaner vehicles and to promote public transport, walking and cycling.  But it is debatable how effective these measures will be in the short term.

“What we should always bears in mind is the ultimate goal of improving air quality, that is, to protect public health.  And this can only be achieved by reducing pollutant emissions, in particular from the most polluted old vehicles.  The cost of air pollution to the economy and NHS per year far exceeds the investment of £3 billion proposed and therefore it is essential that more aggressive measures are in place to reduce pollutant emissions.”

Prof. Ian Colbeck, Professor of Environmental Science, University of Essex, said:

“Despite acknowledging that air pollution results in £2.7bn in lost productivity there’s little urgency to tackle the problem.  Again it is left up to local authorities for solutions and they have until December 2018 to come up with their proposals.

“The plan notes that Clean Air Zones, that include charging, will reduce air pollution in “the shortest possible time”.  However the Government is asking local authorities to consider other measures as the first option.”

Prof. Bill Collins, Professor of Climate Processes, University of Reading, said:

“The replacement of petrol and diesel vehicles by electric ones seems to be rapidly gathering pace.  This will benefit both climate change and air pollution.  Diesel engines are the largest source of nitrogen dioxide in cities, a harmful gas which has been linked to around twenty thousand premature deaths in the UK each year.  Electric cars still produce pollution as fine particles from tyres and brakes, but are far cleaner than the current fossil-fuelled fleet.”

Prof. Alastair Lewis, Professor of Atmospheric Chemistry, National Centre for Atmospheric Science, University of York, said:

“Although air quality in the UK is clearly very much better than some other parts of the world, the economic case to continue to improve it is overwhelming, even though technically this becomes more and more challenging.

“The costs to the economy, through lost productivity and costs to the NHS are measured in the billions of pounds per year, and could well increase further with an ageing population.

“Given the rate of improvement in battery and electric vehicle technology over the last ten years by 2040 small combustion engines in private cars could well have disappeared without any government intervention.  Nonetheless this reported new announcement of a ban is highly symbolic since it signals to both the public and to manufacturers that there is no turning back from electrification.  It will go down as significant milestone in the history of air pollution in the UK.

“Eliminating petrol and diesel engines from cities will have the most beneficial impact on reducing roadside exposure to NO2 and fine particulate matter (PM), but the policy will not in isolation completely ensure good air quality for everyone.

“Electric vehicles have no direct tailpipe emissions but they are still a source of PM from brake and tyre wear and through agitating road dust.  There still remain many other urban sources of pollution not only from transport, but also heating, construction, domestic emissions, and external sources of pollution that drift into cities from outside, most notably from the agricultural sector.  Some other urban sources of pollution are even on an upwards trend, most notably from wood burning stoves.

“If we look forward five to 10 years it is highly likely that the current NO2 problems in urban centres will have noticeably diminished, but it may leave us with PM and ozone as the two stubborn pollutants that prove hardest to reduce to the levels recommended by the World Health Organisation.

“Controlling NO2 is relatively straightforward – if a molecule is removed from the tailpipe the amount in air responds proportionately.  For PM and ozone much more complex chemistry occurs in the atmosphere, where controls on emissions do not always give one-to-one improvements in air quality.

“For some particles and for ozone very large reductions in their precursor emissions can be needed to generate sometimes only modest improvements in air quality.”

* https://www.gov.uk/government/publications/air-quality-plan-for-nitrogen-dioxide-no2-in-uk-2017

Declared interests

Prof. Alastair Lewis: “No interests to declare.”

None others received.