Air quality and noise exposures near an urban freight railyard in Canada

Growing demand for freight rail alongside trends in residential land use can lead to increased railyard activity near populations. Railyard locomotive and train movements generate air and noise pollution associated with adverse health effects. We sampled gaseous and particulate pollutants and measured sound levels over 15 months in a Toronto (Ontario, Canada) residential neighbourhood surrounding an active freight marshalling railyard. Analyses showed that both air pollutant concentrations and noise levels were higher in the railyard neighbourhood compared to non-railyard-influenced urban locations, notably during overnight hours. The composition of fine particulates in the railyard neighbourhood was enriched in elements consistent with railyard-relevant sources, such as wheel and rail abrasion, soil dust, and diesel fuel combustion exhaust. Railyard neighbourhood concentrations of toxic polycyclic aromatic hydrocarbons were also elevated. Noise modeling showed that railyard sources contribute to locally elevated noise levels and noise characteristics. Thus, railyard neighbourhoods may have comparably high combined multi-pollutant exposures, inclusive of noise exposure. These findings can inform mitigation strategies for reducing air pollutant and noise exposure health risks for populations living near freight transportation hubs.