KCL study finds London air pollution from traffic improving, but continues to exceed limits in many parts of city
Green Car Congress
SEPTEMBER 5, 2016
This contrasted with the trends for the preceding five year period (2005–2009) when a wider upward tendency was observed in ΔNO 2 concentrations; this can be attributed in part to a 3% rise in the number of diesel buses and coaches between 2005 and 2009 and to the failure of tighter Euro class emissions standards. Roadside PM 2.5
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