One thousand London buses are to be retrofitted to reduce their PM10 and NOx emissions.
Transport for London has been trialling equipment which is fitted to the exhausts of buses to reduce the amount of pollution they generate.
55 buses on routes 7, 10, 48, 49, 56, 148 and 205 will be retrofitted to cut PM10 levels while up to 1,000 older buses will be fitted with equipment to reduce their NOx emissions.
TfL say in pilots the equipment with reduced PM10 emissions by 77 percent and NOx by 88 per cent.
Announcing the roll-out of the retrofitting programme, Mayor Boris Johnson said: “I am committed to delivering cleaner air in London and we are pushing the boundaries of current technology to achieve this.’
Poor air quality in the capital contributes to thousands of premature deaths each year and critics say the Mayor needs to do more to address the problem.
Last year the capital was given an extension to meet EU limits for emissions.
The Mayor has since implemented the delayed third phase of the Low Emission Zone and launched a campaign to discourage idling by motorists.