Data released today (Tuesday 27 September 2016) from the World Health Organization (WHO) indicates that over 90 per cent of the UK’s population lives in areas where levels of air pollution exceed WHO limits.

Air pollution increases the risk of respiratory and cardiovascular diseases, stroke, lung cancer, acute respiratory infections and other diseases. Major sources of outdoor air pollution include transport, burning of waste and household fuel, coal-fired power plants, and industrial activities. Globally, it is estimated that 3 million deaths a year can be attributed to outdoor air pollution.

A new air quality model released by the WHO estimates that 92 per cent of the world’s population live in areas where levels of air pollution exceed WHO limits. The model was developed in collaboration with an international team of scientists led by the University of Bath, United Kingdom and represents the most detailed outdoor (or ambient) air pollution-related data ever reported by WHO.

A major risk to public health

The model provides information on levels of particulate matter, known as PM2.5, that have a diameter of less than 2.5 micrometres. These ultra-fine particles, that include sulphate, nitrates and black carbon, can penetrate deep into the lungs and into the cardiovascular system, posing considerable risk to human health.

The model estimates that more than 90 per cent of the UK population lives in areas where levels of PM2.5 are higher than WHO air quality limits.

Dr Gavin Shaddick, of the University of Bath’s Department of Mathematical Sciences and Deputy Director of the Bath Institute for Mathematical Innovation, led the international research team.

Dr Shaddick said: “Globally, air pollution presents a major risk to public health and a substantial number of lives could be saved if levels of air pollution were reduced.

“The model we have developed provides a wealth of information related to air quality around the world and highlights areas that exceed WHO air quality limits. This information is vital for health impact assessment, informing policy and the development of mitigation strategies.

“The model successfully integrates data from many sources to provide information on levels of fine particulate matter, one of the pollutants most strongly associated with adverse health outcomes. It provides comprehensive data on air quality for all countries, including areas where ground monitoring may be sparse.”

International research collaboration

The research team consists of sixteen leading scientists from eight international institutions together with the WHO. This group includes Professor Jim Zidek, from the University of British Columbia who was the Bath Institute for Mathematical Innovation Global Chair from 2015-16. Matthew Thomas and Amelia Jobling, both at the University of Bath, assisted with the development and implementation of the model. The model was run on the University’s £1 million high performance computer facility, Balena.

Dr Flavia Bustreo, Assistant Director General at the WHO said: “The new WHO model shows individual countries where their air pollution danger spots are, and provides a baseline for monitoring progress in combatting it.”

“Air pollution continues to take a toll on the health of the most vulnerable populations - women, children and the older adults,” adds Dr Bustreo. “For people to be healthy, they must breathe clean air from their first breath to their last.”

WHO has produced an interactive map of global air quality.

88 per cent of mathematical sciences research from the University of Bath was judged to be internationally excellent by the in the recent independently-assessed Research Excellence Framework 2014.