Impact of London’s low emission zone on air quality and children’s respiratory health: a sequential annual cross-sectional study
Low emission zones (LEZ) are an increasingly common, but unevaluated, intervention aimed at improving urban air quality and public health. Authors investigated the impact of London's LEZ on air quality and children's respiratory health.
The authors did a sequential annual cross-sectional study of 2164 children aged 8–9 years attending primary schools between 2009–10 and 2013–14 in central London, UK, following the introduction of London's LEZ in February, 2008. They examined the association between modelled pollutant exposures of nitrogen oxides (including nitrogen dioxide [NO2]) and particulate matter with a diameter of less than 2·5 μm (PM2·5) and less than 10 μm (PM10) and lung function. They assigned annual exposures by each child's home and school address, as well as spatially resolved estimates for the 3 h, 24 h, and 7 days before each child's assessment, to isolate long-term from short-term effects.
The main findings of the study are that within London's LEZ, a smaller lung volume in children was associated with higher annual air pollutant exposures. Authors found no evidence of a reduction in the proportion of children with small lungs over this period, despite small improvements in air quality in highly polluted urban areas during the implementation of London's LEZ. Interventions that deliver larger reductions in emissions might yield improvements in children's health.
Authors: Ian S Mudway, Isobel Dundas, Helen E Wood, Nadine Marlin, Jeenath B Jamaludin, Stephen A Bremner, et al., The Lancet Public Health