Vehicles using diesel fuel are the leading cause of air pollution in London.
Although measures have been put in place to discourage their use, the Institute for Public Policy Research (IPPR) says that they are not enough to help the UK meet its air pollution targets.
“London’s air is both lethal and illegal,” Harry Quilter-Pinner a, researcher at IPPR, told the Guardian.
He said: “This is a public health crisis and it should be ignored no longer. Only bold action will make the capital’s air safe to breathe again.”
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Diesel engines produce less carbon dioxide than their petrol equivalents, but they also produce nitrogen oxides and small particles, which can cause breathing difficulties in vulnerable people.
The IPPR’s Lethal and Illegal report found that if more is not done about diesel pollution, London will not meet its legal requirements on air quality until 2025 or later.
Experts from the RAC Foundation said that other alternatives should be found to improve air quality, including increasing the number of charging points for electric vehicles.
A scrappage scheme would allow motorists to trade in their diesel vehicles for alternative cars at a lower cost, with funding coming from the Government.
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But the RAC’s chief engineer David Bizley believes such a solution would only pay off if it were to include the UK’s worst road offenders - public transport and commercial vehicles.
He said it is more likely to be older buses and commercial vehicles that account for the largest share of emissions.
As part of the Clean Air Action plan, drivers of older, less environmentally friendly cars sold before 2005 will have to pay a £10 pollution charge to enter central London from 2017.
London’s new Ultra Low Emission Zone is also set to be rolled out in 2019. Drivers wishing to enter the ULEZ will have to ensure their vehicle meets emissions standards or pay a fee.
Initially applying to inner London, the ULEZ would be expanded from 2020 to the North and South Circular for motorcycles, cars and vans, and across the capital for lorries, buses and coaches.