Compared with central London, the air in Paris seems relatively clean, except that there is a permanent whiff of diesel fumes that is pervasive on the main thoroughfares in the rush hour.
Now, French scientists and the authorities responsible for controlling air pollution are starting to talk about the "sensitive" subject of the possible effect of diesel fumes on health.
Government pricing policy has encouraged diesel fuel use. It is up to 25 per cent cheaper than leaded or lead-free petrol and almost half the vehicles on French roads has a diesel engine, a three-fold increase in 10 years.
A few years ago, if you went to a French service station at a busy time of day with a petrol-engined car, there were queues at all pumps. Now, you will often overtake a long queue of cars waiting for the diesel pumps and fill up immediately.
Last week, though, diesel drivers confronted a worse threat than queueing. A headline in the main evening paper screamed: "Diesel to rise to the price of petrol." Yesterday it became known that the agency for the environment and energy control had completed a report on traffic fumes and health, proposing six new studies. These would include a study on the effects of pollutants, including lead and the components of diesel fumes, and the effect of frequent stopping in urban areas.
A science article in the Figaro spoke of the "pernicious effects of the fashion for diesel" and said diesel combustion produced very fine particles that went to the lungs and were particularly toxic. It expressed surprise that the effects had been so poorly researched and regretted that few health specialists had taken part in discussions.
It cited figures for the Ile de France region that showed increases in the number of days spent in hospital by asthma sufferers and in the number of visits to the doctor in connection with lung and breathing problems. These increases were matched by increases in cardio-vascular problems and showed a correlation with the rates of increase of fine particles in the atmosphere from diesel fumes.
Although diesel pollution is coming into the open, there is no sign that drivers are buying cars for other considerations than fuel and price economy.
In Britain, consumers are not being turned off by environmental fears over diesel cars. About 22 per cent of the 1.9 million new cars sold in Britain last year were diesel, with Ford's Mondeo and the Peugeot 405 the most popular models. This compared with 3 per cent of the market 10 years ago. Half the new vehicles sold in Britain every year are company cars and more businesses are choosing diesels because they are more cost-efficient.
Most car markets have seen a growth in sales of diesels due to favourable tax regimes. Quality car producers, such as Mercedes and BMW, have begun production and of the big executive car producers, only Jaguar does not make a diesel model.
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