Environmental Issues in London

The premature deaths are due to two key pollutants, fine particulates known as PM2.5s and the toxic gas nitrogen dioxide (NO2), according to a study carried out by researchers at King’s College London.

The study – which was commissioned by the Greater London Authority and Transport for London – is believed to be the first by any city in the world to attempt to quantify how many people are being harmed by NO2. The gas is largely created by diesel cars, lorries and buses, and affects lung capacity and growth.

London, Birmingham, and Leeds are among the UK cities that have been in breach of EU safety limits on NO2 for five years, prompting legal action that led to a supreme court ruling in April that the government must publish a clean-up plan by the end of the year.

Previous research attributed 4, 267 annual premature deaths to PM2.5s in 2008, based on 2006 levels of the particulates. Subsequent falls in those particulates and a change in methodology that excludes natural sources of the pollutant sees that figure fall to 3, 537 for 2010 levels of PM2.5s in the new study.

However that fall is more than cancelled out by the addition of an estimated 5, 879 deaths from NO2 each year, bringing the total early deaths from both pollutants in 2010 to 9, 416.

Matthew Pencharz, the deputy mayor for environment and energy, said that local authorities could only do so much and the government needed to step in. “It’s [the new research] an important message for government, where the supreme court judgment has already focused minds.”

Although the report found that a larger proportion of deaths caused by PM2.5 were from particulates that originated outside the city than within it, it found that most of the deaths linked to NO2 were because of NO2 emissions from diesel vehicles and other sources within the capital.

London air pollution: which mode of transport has the highest exposure?

Last year, mayor Boris Johnson came in for criticism after a King’s researcher published figures showing Oxford Street had the worst NO2 levels in the world, largely because of its high concentration of diesel buses. The mayor later called for a diesel scrappage scheme to tackle pollution in the capital.