Citizen science in London – local residents map air pollution and challenge roadbuilding plans

The following is a rough-and-ready amalgam of two press releases distributed this week by the No to Silvertown Tunnel campaign to various London and UK-wide media outlets…

Across southeast and east London, people are living with air pollution at levels up to two-and-a-half times legal limits. According to local residents, the situation will worsen considerably if plans for two controversial infrastructure projects are given the go-ahead.

Community campaigners in the London boroughs of Greenwich and Lewisham joined forces in January 2014 to monitor levels of nitrogen dioxide in the atmosphere, in what is believed to be the largest citizen science air pollution study ever conducted in the capital.

Nitrogen dioxide, which is emitted in motor vehicle exhausts, is the cause of the brown haze often seen on urban horizons. Prolonged exposure to nitrogen dioxide causes respiratory problems, and can lead to cancer and premature death. It also hinders the development of children’s lungs.

The citizen science study undertaken by a coalition of the No to Silvertown Tunnel campaign, Don’t dump on Deptford’s Heart, and the Network for Clean Air, involved recording nitrogen dioxide levels over the space of a few weeks at 150 sites across five London boroughs. The results show horrifying pollution levels right where people live, work, play, shop and go to school.

A proposed cross-river road tunnel between Greenwich and the Royal Docks in Silvertown, supported by Transport for London and the London boroughs of Greenwich and Newham, would add massively to pressure on the road network in the region. Adding to road capacity encourages more traffic onto local roads, and increases air pollution in the long term, damaging health and worsening the overall quality of life for residents.

A proposal from Thames Water to build a 17 metre wide shaft in Deptford, as part of its “super sewer” plans, would mean the partial closure of an already congested arterial road for more than a year, causing chaos on all major roads in the area.

The European legal limit for nitrogen dioxide pollution is 40 microgrammes per cubic metre, averaged over a year. In a number of UK cities we have seen this so-called limit value exceeded to the extent that the European Commission recently launched a legal action against the UK government for failing to meet its air quality commitments.

In the latest citizen science study into air pollution in southeast and east London, nitrogen dioxide levels up to 110 µg/m³ were recorded along roads that would be affected by the proposed Silvertown Tunnel and Deptford super-sewer works. This is approaching three times the legal limit.

In more local detail…

  • A nitrogen dioxide level of 110 µg/m³ was recorded at the New Cross one-way system, blighting homes, student halls and Goldsmiths College. In total, five sites on the A2 from Deptford to New Cross recorded levels over double the EU limit.
  • Lee High Road in Lewisham town centre recorded 109 µg/m³. The road network here will come under extra pressure if the Silvertown Tunnel is built.
  • Children walking to school in Charlton face a level of 104 µg/m³ at the Bramshot Avenue underpass, underneath the congested A102 dual carriageway, which is expected to cope with extra traffic from the Silvertown Tunnel.
  • Levels of twice the legal limit were seen on Millennium Way on the Greenwich Peninsula, where Greenwich Council plans to build a new primary school. Levels well above the the limit were also recorded outside the Royal Greenwich University Technical College, Windrush and Fossdene primary schools in Charlton, as well as Deptford Park primary, Deptford Green School, and Addey and Stanhope secondary schools.
  • A level of 88 µg/m³ was recorded on the Catford one-way system – more than twice the legal limit. The historic town centre of Greenwich, a world heritage site, is blighted by air pollution at almost twice the legal limit.

The latest measurements may be spot values rather than annual averages, but the data are consistent with those recorded in a previous study carried out by No to Silvertown Tunnel in the summer of last year. The community campaigners do not pretend to be doing peer-reviewed research, but their studies are rigorous, and the results have been critically reviewed by independent scientific experts.

Extensive media coverage of a recent Saharan dust cloud over London brought air pollution issues to public attention, but the dust coating parked cars was only a small part of a much larger and far less visible problem. It takes diligent scientific investigation to provide a full picture of air quality and airborne health hazards.

The community campaigners behind this citizen science study are making a positive contribution to a wider public health investigation, as well as highlighting local issues around transport infrastructure and quality of life. They plan now to combine their data with local authority-collated figures, in order to derive a fuller picture of air pollution across the region.

No to Silvertown Tunnel spokesman Darryl Chamberlain said: “Generations of local people have paid the price for a lack of investment in new public transport, walking and cycling facilities, while politicians prioritise the profits of property developers over people.”


(1) Photos, further detailed information and quotes for publication are available on request.

(2) Full results from the air pollution study are available here:

(3) The No to Silvertown Tunnel study was supported with funding from individual campaign supporters and the Network for Clean Air.

(4) The Don’t dump on Deptford’s Heart study was conducted with help and funding from the Network for Clean Air, the Greenwich Co-operative Development Agency, Joan Ruddock MP and Deptford First.