Spatial and temporal associations of road traffic noise and air pollution in London: Implications for epidemiological studies. (March 2016)

• Record Type: Journal Article
• Authors: Fecht, Daniela; Hansell, Anna L.; Morley, David; Dajnak, David; Vienneau, Danielle; Beevers, Sean; Toledano, Mireille B.; Kelly, Frank J.; Anderson, H. Ross; Gulliver, John
• Is Part Of: Environment international. Volume 88(2016:Mar.)
• Page Start: 235
• Page End: 242
• Publication Date: 2016-03
• Subjects: Noise -- Air pollution -- Road traffic -- Exposure assessment -- Correlation -- London; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2015.12.001
• Languages: English
• ISSNs: 0160-4120

Abstract

Abstract: Road traffic gives rise to noise and air pollution exposures, both of which are associated with adverse health effects especially for cardiovascular disease, but mechanisms may differ. Understanding the variability in correlations between these pollutants is essential to understand better their separate and joint effects on human health. We explored associations between modelled noise and air pollutants using different spatial units and area characteristics in London in 2003–2010. We modelled annual average exposures to road traffic noise (LAeq, 24 h, Lden, LAeq, 16 h, Lnight ) for ~ 190, 000 postcode centroids in London using the UK Calculation of Road Traffic Noise (CRTN) method. We used a dispersion model (KCLurban) to model nitrogen dioxide, nitrogen oxide, ozone, total and the traffic-only component of particulate matter ≤ 2.5 μm and ≤ 10 μm. We analysed noise and air pollution correlations at the postcode level (~ 50 people), postcodes stratified by London Boroughs (~ 240, 000 people), neighbourhoods (Lower layer Super Output Areas) (~ 1600 people), 1 km grid squares, air pollution tertiles, 50 m, 100 m and 200 m in distance from major roads and by deprivation tertiles. Across all London postcodes, we observed overall moderate correlations between modelled noise and air pollution that were stable over time (Spearman's rho range: | 0.34–0.55 |). Correlations, however, varied considerably depending on the spatial unit: largest ranges were seen in neighbourhoods and 1 km grid squares (both Spearman's rho range: | 0.01–0.87 |) and was less for Boroughs (Spearman's rho range: | 0.21–0.78 |). There was little difference in correlations between exposure tertiles, distance from road or deprivation tertiles. Associations between noise and air pollution at the relevant geographical unit of analysis need to be carefully considered in any epidemiological analysis, in particular in complex urban areas. Low correlations near roads, however, suggest that independent effects of road noise and traffic-related air pollution can be reliably determined within London. Highlights: Largest study of the relationship of noise and air pollution in space and time. Correlations of noise and air pollution metrics across different spatial units. Overall moderate correlations between levels of noise and air pollution in London. Correlations vary greatly in magnitude by size of spatial unit. Studies should consider the variability in co-linearity of noise and air pollution.