Does wearing a face mask really protect against air pollution?

The tests on the volunteers revealed that the average leakage from the masks ranged from as low as three percent to as much as 68% while the participants performed sedentary tasks such as sitting.

Despite being a common sight in polluted cities, particularly those in Asia, new research suggests that face masks designed to filter out pollution particles may not be as effective as they claim to be.

Carried out by an international team of researchers from Heriot-Watt and the Institute of Occupational Medicine in the UK, the study assessed the effectiveness of a selection of masks in Beijing.