London and Paris were both found to exceed legal limits for nitrogen dioxide and airborne particle pollution، according to a study.
For the first time، the study measures the impact of policies introduced in 2010 designed to reduce air pollution from urban traffic over the last twelve years.
It found that despite efforts across both cities to combat air pollution، neither have achieved compliance with the objective، set by the World Health Organisation. Researchers، from King's College London and Airparif، a French air quality monitoring organisation، measured the impact of policies designed to reduce air pollution from urban traffic since 2005.
They found that policies put in place to tackle air pollution have led to improvements but overall، the rate of change is 'not enough'.
The team analysed the levels of pollution over two time periods، 2005-2009 and 2010-2016.
Since 2010، they found that there have been improvements in levels of nitrogen dioxide and particle concentrations across both cities. Nitrogen dioxide (NO) is a toxic gas caused by diesel vehicles and a major air pollutant which causes significant health effects.
Breathing air with a high concentration of NO can irritate airways in the human respiratory system.
As the legal compliance approached in 2010، nitrogen dioxide in both cities was getting worse.
Despite passing stringent laboratory tests، new diesel cars failed to achieve anticipated reductions when driven on the roads.