Taxing journey

Researchers have discovered that your level of exposure to pollution can vary according to what method of transport you use, with travelling by taxis resulting in the highest levels of exposure and walking the least.

Research published in the journal Atmospheric Environment, describes how the team from Imperial College London and the Health and Safety Laboratory, Buxton, measured and visualised exposure to pollution levels, while using a variety of different transport methods for travelling across London.

The researchers looked at five modes of transport, including walking, cycling, car, taxi and bus, and measured levels of exposure to ultrafine particles when travelling on them using a newly developed system that uses in combination an ultrafine particle counter and video recorder.

Ultrafine particles are less than 100 nanometres in diameter and mainly traffic related. Their small size and large surface area means it is possible to inhale large quantities which makes them particularly dangerous.