Air pollution in parts of Silvertown is more than one-and-a-half times the European legal limit, according to a new study.

Campaigners from the No to Silvertown Tunnel group, who carried out the research, warn levels will get worse should the Newham Council-backed road tunnel connecting the Royal Docks to the Blackwall Tunnel approach at North Greenwich get the go-ahead.

The group monitored nitrogen dioxide levels at 150 sites across Newham and four other London boroughs in January.

The results showed the nitrogen dioxide level at the site of the tunnel’s planned northern portal in Dock Road was 62 microgrammes per cubic metre, far greater than the EU legal limit of 40 microgrammes per cubic metre.

Readings at the junction of Greengate Street and Barking Road in Plaistow measured nitrogen dioxide levels as 71 microgrammes per cubic metre in the middle of a residential area and levels of 50 microgrammes per cubic metre were recorded both at the junction of Mill Road and North Woolwich Road and at the northern end of Silvertown Way, by Canning Town station.

Prolonged exposure to air pollution causes respiratory problems and can lead to cancer. Pollution from motor vehicles can also affect the development of children’s lungs.

Darryl Chamberlain, spokesman for No To Silvertown Tunnel, said: “Local politicians are backing dangerous plans for the Silvertown Tunnel rather than taking a stand against the lethal air pollution that blights our communities, and the traffic that causes it. A new tunnel will only bring extra traffic - it won’t bring relief from congestion or pollution.

“It’s time we took a stand and worked together to reduce the traffic on our roads, instead of encouraging more vehicles from Kent and Essex to clog up our roads and pollute our neighbourhoods. Newham Council, Greenwich Council and the Mayor of London must rethink their support for the Silvertown Tunnel before it’s too late.”

Andrew Wood of Network for Clean Air said: “These results bear out what we know: the failure of Boris Johnson to address air pollution is damaging health and London’s economic development.

“The Mayor of London needs to immediately appoint a Commissioner for Air Quality with a task force to knock heads together.”