• WHY are black taxis allowed to leave their engines idling in taxi ranks, particularly outside major stations like Euston and King’s Cross when it is proven that this is the worst form of pollution particularly for pedestrians?

Surely now traffic wardens should be on the look-out to give immediate on-the-spot fines to illegally idling black cabs, cars and lorry drivers throughout the Camden area.

The awful irony is that black cab drivers, lorry drivers and car drivers, sitting in their idling cars suffer the most air-pollution effects?

As taxis and minicabs are obviously on the roads the most and are therefore the highest NO2 and particulate polluters, surely legislation and incentives can be applied to reduce the number of diesel engines on the road together with a campaign to re-educate and inform pedestrians, drivers, and local authorities of their rights and duties.

The increase in congestion charge on all diesel cars is merely a sticking plaster and revenue generator, but will not resolve the underlying issues as most people will still continue to pay the extra fee and drive the cars as normal.

DANIEL TAPSELL, SW1