40 years of legislation reduced air pollution ‘significantly’

Policies to improve air quality in the UK over the past 40 years are saving lives and ‘significantly’ reducing pollution, but more work is still to be done, a major research project has found.

The study, which was led by the Centre for Ecology & Hydrology, charted emissions of a variety of air pollutants in the UK between 1970 and 2010, when there was a host of different legislation and technology introduced to combat air pollution such as the 1979 UN Air Convention, major UK legislation such as the Clean Air Act 1993, Environment Act 1995 and several Air Quality Standards Regulations, plus a series of EU directives relating to different pollutants.

It revealed total annual emissions of PM2.5 (fine particulate matter), nitrogen oxides (NOx), sulphur dioxide (SO2) and non-methane volatile organic compounds (NMVOC) in the UK all reduced ‘substantially’ — by between 58% and 93%.

The scientists behind the project believe their study is ground-breaking due to the long timeframe studied and the removal of weather factors from modelling, meaning any changes in air pollution can be directly attributed to emission levels.

However, it found that ammonia emissions have been on the rise in recent years.

Ammonia has been called the ‘poor cousin’ of air pollution as it has flown below the radar of regulators, despite its destructive impacts.

According to official figures, farming is responsible for around 88% of all UK emissions of ammonia gas which can travel long distances, is damaging to the environment and combines with other pollutants to form particulates.

The report also warned that NOx levels are still well above legal levels in many towns and cities.

Edward Carnell of the Centre for Ecology & Hydrology, lead author of the study, said: ‘Technology advances over the past 40 years, such as the three-way catalytic converter for cars and equipment to reduce sulphur and nitrogen dioxide emissions from large power plants have contributed to significant reductions in emission levels and therefore improved public health.

‘However, it is legislation that has driven these technological improvements.’

Dr Sotiris Vardoulakis of the Institute of Occupational Medicine in Edinburgh, one of the co-authors of the study, added: ‘Concerted action is needed by the government, local authorities, businesses and individuals to further improve air quality and protect human health.’

The study, which also involved the Universities of Oxford, Birmingham, Edinburgh and Exeter, was funded by the Natural Environment Research Council (NERC). It has been published in the journal Environmental Research Letters.