An article has recently appeared in the British Medical Journal warning of the dangers to public health in the UK caused by air pollutants. In 2011 a report from the House of Commons Environmental Audit Committee suggested that the costs to society from poor air quality were on a par with those from smoking and obesity. Air pollution has fallen sharply over the last 25 years, in particular nitrogen oxide levels have dropped by two thirds and particulates have halved. However, whilst the pollution levels have fallen, the medical profession is now better able to quantify the damage caused.