Spatial Relationships of Air and Noise Pollution from Road Traffic in London: the TRAFFIC Study

Abstract

Background: There is a strong body of evidence linking air pollution with adverse health effects as well as a growing literature on health effects from noise but evidence is mixed. The possible joint effects of air and noise pollution are however understudied and have rarely been considered in environmental epidemiological research, although there is well-established evidence from occupational settings. Environmental exposures to air pollution and noise pollution in urban areas should exhibit some correlation as they both are strongly influenced by traffic. Differences in these associations in space and by air pollution metric are however largely unknown. Aim: To study associations between exposure to traffic-related air pollutants and noise pollution for residential postcode centroids and neighbourhoods in London. Methods: Air pollution was modelled using the dispersion model London Air Quality Toolkit (LAQT). Noise pollution was modelled using a model developed for the NERC/MRC funded TRAFFIC study based on the UK Calculation of Road Traffic Noise (CRTN) method. Exposure to air pollutants (Total and traffic only PM10, NO2, NOX) and LAeq16 and LNight for noise were modelled for ~220,000 postcode centroids in London. .We aggregated estimates from postcode centroids to small areas and compared each of the air pollution metrics with the noise pollution metrics at both levels. Data for 2003 and 2010 were analysed to study change in associations over time. Results: Preliminary results suggest that there are high correlations between air pollution and noise across London but the degree to which they correlate differs between different metrics and between neighbourhoods. Further analysis is currently being carried out and full results will be presented. Conclusions: Understanding the differences in spatial correlation between traffic-related air pollution and noise exposure is important to evaluate the potential joint effects of air and noise pollution.