Smoking harmful to your car's resale health

It didn't help actor Yul Brynner, who sounded the warning after contracting a fatal cancer, but it could help you at trade-in time. Keeping tobacco smoke away from your car's cabin is likely to add hundreds, or even thousands, to its secondhand price. And it's almost certainly helping your health as well.

A friend of Carsguide emails this week to raise the question of smoking in cars, after an interesting encounter during his morning commute. "I saw a woman this morning in a brand-new BMW 5 Series smoking her lungs out with all the windows up and pondered if this would affect resale. I reckon a non-smoker's car must be worth more," he says.

A quick call to Glass's Guide, the Australian authority on secondhand sales, reveals nothing substantial but a clear pointer. "We do not consider smoking as a criteria while predicting residual values," says Rashad Parkar.

"However, we believe that smoking does have a detrimental effect when it comes down to car valuation. If the car has cigarette marks or damaged upholstery due to smoking this will definitely impact residual values in a negative manner."

But things are more black-and-white in the USA, where research shows that even a heavy tobacco odour can put people off a car. The only serious study we can find on the subject is from San Diego in 2008 and it says a smoker's car would be worth up to nine per cent less in the USA.

Surprisingly, more than 20 per cent of cars for sale were owned by smokers or had been smoked in during the previous year, where more than 90 per cent of non-smokers banned any sort of tobacco ignition in their cars.

The study is funded by an anti-tobacco group so needs to be put into context, but lists more than 4000 chemicals in secondhand smoke and nicotine levels 30 times higher in smoker's cars than ones which are tobacco free.

"When tobacco is smoked in the enclosed environments of passenger cars, air concentrations of tobacco smoke pollutants can become extremely high. Many of the pollutants attach to surfaces and accumulate in duster from where they can be released back into the air over days and weeks after smoking," says Penelope Quintana, one of the study's author and a professor in the school of public health in San Diego.

The American research is nasty stuff but the everyday crackdown on smoking since then is bound to be producing an even bigger impact, as smoking becomes less and less tolerated in all areas of everyday life. The changing attitude is also reflected in the way car companies look at smoking.

These days, many cars do not have an ashtray and the cigarette lighter has become a power socket. It's a huge contrast to the days when Jaguar had identical chromed ash receptacles at three points in its XJ limousine, allowing the owner - or fiery journalists - to rotate them until all three were choked and in need of a full-scale clean out.

If you want a cigarette lighter in a BMW you must pay extra. And it's been that way for years. But power sockets are spreading faster than nicotine addiction and most cars have at least three, with the highest plug-in count we've discovered in an American SUV with six.

Cigarettes are on the way out but now we're plugging in phone chargers and GPS navigation systems on a daily basis, as well as back-seat entertainment systems and - once again, in the USA - beverage warmers for the giant coffee containers the seem to be compulsory for commuters.

But we still have to ask if we're swapping one danger for another in cars, stubbing out the cigarette threat but plugging in giant distractions that can easily lead to more trouble than a slump in the secondhand price.

This reporter is on Twitter: @paulwardgover