Just before the general election was announced, criticism of the Government’s Clean Air Act made air pollution big news.

Despite this, most of the parties have failed to address an environmental issue which affects UK cities and over half of the UK population. Let’s have a look at how an issue barely mentioned in the manifestos will play out across the country.

Data from Public Health England provides estimates of particulate matter –  the sum of all solid and liquid particles suspended in air many of which are hazardous – on a local authority basis. This allow sus to look at the geography of something that is both responsible for a number of deaths and has recently been linked to poor sleep.

The 10 local authorities with the worse and best air quality. Source: Public Health England.

Three findings emerge from the data:

Firstly, London boroughs dominate the list: the 19 local authorities with the worst pollution in Britain are all in London. Westminster and Kensington, two of the richest authorities in the country, lead this list. It’s estimated that long term exposure to air pollution was to blame for 8.3 per cent of all deaths in 2010 in these two areas.

Secondly, and unsurprisingly, urban areas have worse air quality. When looking at the 50 most polluted local authorities, just five are outside of urban areas (you can see our definition of urban here). Meanwhile those least polluted tend to be rural authorities.

Thirdly, larger urban authorities aren’t necessarily the most polluted. Nottingham, Leicester and Luton have worse air quality than Manchester. Ipswich has higher levels of particulate matter than London, and York and Glasgow are among the least polluted cities in the UK.

Ed Glaesar would describe pollution as a “demon of density” – a downside of concentrating growth in specific places. While it may have fallen off the agenda in this election, it’s a problem that both central government and cities must tackle if they are to stay attractive to both people and businesses.

London already has a low emissions zone, a traffic pollution charge scheme with the aim of reducing the tailpipe emissions of diesel-powered commercial vehicles; and Sadiq Kahn is proposing further restrictions, including a new toxicity charge to be introduced from autumn 2017. Similar steps will be required to tackle this problem elsewhere.

Adeline Bailly is a research intern at the Centre for Cities, on whose blog this article originally appeared.