Swedish carmaker Volvo has launched a campaign called Emissions Equality, calling for greater openness on harmful emissions from cars.

Attempting to draw attention to pollutants beyond CO2, the car maker says focusing on lower CO2 scores has allowed focus to shift from other pollutants.

Volvo's Regional President of UK, Ireland and Iceland, Peter Rask, says the "focus on CO2 alone gives a false picture".

Currently, consumers are told how much CO2 a car emits. But Rask says buyers should also be told about the level of nitrogen oxide (Nox) and hydrocarbons emitted by their vehicles.

Whereas CO2 emissions have a harmful effect on the environment over the long term, "the other emissions affect us today", he reasons.

Volvo hopes to highlight the issue by providing information to its buyers on the entire range of car emissions. If its campaign is successful, then there is likely to be a shift in the economics of car production towards other low-carbon technologies, such as petrol-electric hybrids.