REGARDING Mr Limmer’s letter (Wednesday’s Oxford Mail ViewPoints) and with reference to fumes from diesel engines being a major factor in the cause and spread of lung cancer.

The particulates from a diesel engine, that is the invisible particles that are the cause of pollution, are far lower in a diesel engine than a similar-sized petrol engine.

Vehicle excise duty on each model is based, by the Department for Transport, on the pollution into the atmosphere of these particulates through the exhaust system.

The yearly excise duty on my 1.4 diesel is £35 a year. The excise duty on a similar-sized petrol engine is £165 a year. As to smoking, it’s a filthy habit that kills more people a year than motor vehicles, either petrol or diesel.

KEN ROPER, Morton Avenue, Kidlington