A study carried out by experts at the University of Surrey found that closing windows and turning off fans while a car is stationary can reduce the amount of toxic fumes inhaled by 76%.
It comes as millions of motorists are expected to head out on the road over the bank holiday weekend, with many likely to get stuck in traffic jams.
In the study, researchers found that sitting in traffic with the windows closed and the fans on can increase drivers’ exposure to toxic fumes as pollutants are sucked into the vehicle.
The problem is particularly bad at traffic lights, where fumes from a number of vehicles can linger long after the cars themselves have been driven off.
In built-up cities, the World Health Organisation (WHO) has said that air pollution can be as carcinogenic to humans as smoking.
The WHO has also linked as many as seven million premature deaths a year to air pollution and listed it as one of the top health risks faced by humans.
It is for this reason that drivers should aim to keep their windows closed and fans off whenever possible, senior author of the research Dr Prashant Kumar said.
“Where possible and with weather conditions allowing, it is one of the best ways to limit your exposure by keeping windows shut, fans turned off and to try and increase the distance between you and the car in front while in traffic jams or stationary at traffic lights,” Dr Kumar said.
“If the fan or heater needs to be on, the best setting would be to have the air recirculating within the car without drawing in air from outdoors."
The research, which has been published in the Royal Society of Chemistry’s journal Environmental Science: Processes and Impacts, also found that pedestrians can be affected by toxins at traffic lights.
It follows earlier findings by Dr Prashant’s team showing that drivers stuck at traffic lights were exposed up to 29 times more harmful pollution particles than those driving in free-flowing traffic.