Spatial variability of nitrogen dioxide and formaldehyde and residential exposure of children in the industrial area of Viadana, Northern Italy

Abstract

ABSTRACTChipboard production is a source of ambient air pollution. We assessed the spatial variability of outdoor pollutants and residential exposure of children living in proximity to the largest industry for chipboard production in Italy, aiming at evaluating the reliability of exposure estimates obtained from passive sampling for an ongoing epidemiological study.We obtained data on NO2 and formaldehyde, collected by the environmental protection agency of Lombardia region, at 25 passive sampling sites in the municipality of Viadana during 10 weeks (2017-18), and compared NO2 measurements with average weekly concentrations from continuous monitors. We compared interpolated surfaces of NO2 and formaldehyde for 2017-18 with previous maps for 2010. We assessed the relationship between residential proximity to the industry and pollutant exposures, assigned both using our maps and available countrywide/continental models based on routine monitoring data on NO2, PM10, and PM2.5.The correlation between weekly NO2 concentrations from a continuous monitor and a co-located passive sampler was high (Pearson’s r = 0.89), although passive sampling underestimated NO2 during the cold season. For both 2010 and 2017-18, we observed higher NO2 and formaldehyde concentrations in the southern part of Viadana, with hot-spots in proximity to the industry. PM10 and PM2.5 exposures were higher for children at <1km to the industry and NO2 exposure was higher at 1-1.7 km, compared to the children living at >3.5 km. The density of roads and population was also higher in proximity to the industry.Findings from a variety of exposure models suggest that children living in proximity to the chipboard industry in Viadana are more exposed to air pollution and that exposure gradients are relatively stable over time.