Air pollution in London hit record levels on Thursday due to a combination of traffic fumes, relatively still weather and an influx of dirty air from the north of England and northern France. Official monitoring stations in the capital show that particles, nitrous oxide, sulphur dioxide and other pollutants have reached levels not recorded since stringent new measurements were introduced in 2008. Health advice from the Department for Environment, Food and Rural Affairs (Defra) says that adults and children with lung problems, adults with heart problems and all older people should not take any "strenuous physical activity" while pollution is at the recorded levels. The general population is advised to reduce exercise too. "Recirculated dirty air from Europe and the north of England is partly to blame, along with a lack of wind," the Guardian quoted Gary Fuller, senior lecturer in air quality measurement at King's College London as saying.