Traffic-related nitrogen dioxide exposure modelling in Kaunas cohort study

Abstract

Evidence suggests that air pollution exposure adversely affects pregnancy outcomes. Few studies have examined individual-level intra urban exposure contrasts effects on birth outcomes. We evaluated the impacts of NO2 exposure on low birth weight risk in Kaunas cohort study using modelled air quality data and logistic regression. The relationship between LBW and modelled ambient levels of NO2, using Airviro, a dispersion model developed by the Swedish Meteorological and Hydrological Institute, was evaluated in Kaunas city. We used the ambient air monitoring data from the Kaunas Air Pollution monitoring stations for the Gaussian model validation. The Cohort Database consisted of live singleton births. Maternal exposures to NO2 pollution were assigned to women living in Kaunas city at the time of birth using geographic information systems (GIS). NO2 exposure effect was evaluated as a categorical variable and relative risks were estimated from logistic regression, adjusted for confounding variables. The model predicted NO2 concentrations were by 4.15-3.12% higher than those monitored. After adjustment for gestation age, smoking, family status, education and body mass index, moderate NO2 exposure was associated with a 1.6 times increase in LBW risk (95% confidence interval (CI), 0.79-3.18) and odds ratios (OR) were nearly twice as high in the highest exposure stratum (OR 2.35; 95% CI 0.96–5.75) as the lowest exposure stratum. Findings from our study suggest a general association between NO2 concentrations predicted from Airviro model and those monitored by stationary stations. Little association between modelled traffic-related NO2 pollution and LBW was observed in a population-based cohort with relatively low ambient air pollution exposure