An ad for Dyson's air purifier has been banned for implying that indoor pollution is more damaging to health than outdoor pollution such as vehicle exhaust particles.
The television ad for the company's purifier heater, seen in May, showed a woman at the window of her house looking visibly concerned, before cutting to a car exhaust producing green vapour.
A voice-over said: "What could be worse than the pollution outdoors? Well, the pollution indoors can be up to five times worse where gases and microscopic particles can build up."
The camera followed the woman as she walked into the kitchen, where a number of appliances let off purple and green vapour, including household cleaning products next to a fridge, three potted plants and a hob, while text above them indicated benzene gas, pollen particles, formaldehyde gas and allergens being released.
The ad then showed the purifier sucking in the coloured vapour.
Three viewers complained that the ad exaggerated the health risks posed by pollution levels in a typical domestic kitchen, including by drawing a comparison with a car exhaust.
Dyson said its intention was to raise awareness about indoor air pollution, backing this with a paper from the European Respiratory Journal which stated that concentrations of some air pollutants were two- to five-fold higher indoors than outdoors.
Dyson also provided a study by the US Environmental Protection Agency (EPA) which stated that "indoor air levels of many pollutants may be 2-5 times and occasionally more than 100 times higher than outdoor levels".
The EPA report said indoor air pollution was an issue which required public attention and highlighted several common sources of indoor air pollution including gas hobs, flowering plants and domestic cleaning products.
Dyson said it did not intend to exaggerate the health risks of indoor air pollution by comparing it with car exhaust fumes but said the ad was meant to emphasise the amount of pollutants in the home. The company offered to remove the shot of the car exhaust fumes from the ad.
Upholding the complaints, the Advertising Standards Authority (ASA) said the ad would lead consumers to understand that indoor pollutants were more damaging than outdoor pollutants.
It said the reports provided by Dyson only discussed the presence and types of indoor pollutants and not if they were more damaging to health than outdoor pollutants.
The ASA said: "We considered that the reports were not relevant in determining the comparative damage of indoor and outdoor pollutants and that the evidence was therefore not sufficient to demonstrate that indoor pollution was more damaging than outdoor pollution.
"We therefore concluded that the ad was misleading."
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