3. Results
3.1. Postcode-level associations across all postcodes in London
Spatial patterns of noise (LAeq,24 h) and air pollution (PM2.5traffic) exposure estimates for postcode locations in the centre of London are shown in Fig. 2, stratified by equal sized categories. In general, LAeq,24 h and PM2.5traffic exhibited different spatial distributions with higher noise levels strongly determined by proximity to main roads, while PM2.5traffic estimates, although higher near main roads, were generally more smoothly varying and higher in central London. We observed this spatial pattern for other traffic-related and background air pollutants.