NERC funds hourly traffic pollution monitoring in London

19 September 2014

New state-of-the-art equipment recently installed on Marylebone Road in central London is giving hourly measurements of kerbside traffic pollution in more detail than ever before.

The Xact instrument, funded as part of NERC's 2013 Strategic Environmental Science Capital Call, uses X-ray fluorescence technology to precisely measure the concentrations of 24 different chemical elements.

From this, scientists can work out the individual contribution of non-exhaust sources of traffic pollution, such as brake wear, tyre tread and road dust.

Together with a suite of monitoring equipment already installed at the site, this gives researchers the most complete picture yet of the chemicals that make up traffic pollution. This improved data will help to inform the debate about how best to tackle the problem.

Previously, the samples had to be collected and taken back to the lab for analysis, restricting both the number and regularity of measurements. But the Xact collects and analyses samples automatically and continuously, as often as every 15 minutes, if required.

The equipment was awarded by NERC as part of a £6·5m strategic capital investment aimed at enhancing the UK's research infrastructure.

Investment in research capital such as this is essential to ensure the UK has a well-founded research base to stimulate growth and support the wellbeing of the nation.

The instrument was installed by scientists at King's College London as part of the Traffic project, a £2m research programme whose aim is to better understand the health problems caused by air and noise pollution from traffic in London.

One of those scientists, Dr David Green, says, "This is the first Xact to be used in Europe and the first to be used in a high concentration urban environment like Marylebone Road. It will join the other high time resolution chemical speciation instruments and enable us to measure the non-exhaust and mineral contributions that we have never been able to see before."

Poor air quality in major cities around the world has been linked with a number of health problems, including increased risk of respiratory diseases and heart disease.

Of particular concern are pollution particles less than 10 millionths of a metre across, called PM10. Vehicle exhausts are a known source of these particles, but a recent study in the Hatfield Tunnel on the M1 suggested they are now responsible for only a third of traffic pollution.

Almost half is now down to non-exhaust sources, and Green hopes the data generated by the Xact can be used to design effective policies for dealing with the problem.

The instrument, which is manufactured in the US by Cooper Environmental Services LLC, can also detect fine Saharan dust clouds, such as the one which blew over the UK earlier this year, leaving a thin layer of grime over many of the nation's cars.

Detecting the dust, which can cause sore throats and itchy eyes in healthy people, is vital for producing timely health warnings for those with existing respiratory conditions.

NERC has since provided a further opportunity for the science community to apply for infrastructure investment through the 2014 Strategic Environmental Science Capital Call.

NERC is currently implementing a new process for prioritising capital investment which will be better informed by the views of the community, in line with our approach to investments in national capability and strategic research.

Further information

NERC media office
01793 411568
07785 520929


1. Traffic is a research project funded under the Environmental Exposure & Health Initiative (EEHI), jointly funded by the Natural Environment Research Council (NERC), Medical Research Council (MRC), Department for Environment, Food & Rural Affairs (Defra), Department of Health and the Economic & Social Research Council (ESRC), NE/I008039/1.

Press release: 24/14