Evaluating the joint impact of parental decision to drive and traffic control measures on children’s exposure to traffic-related pollutants during school commutes

The relationship between traffic around schools and children’s exposure to pollution is well estab-lished. Few studies investigated the extent to which parental decisions to drive or walk to schoolshape children’s exposure to traffic emissions, as well as the moderating role of traffic-control condi-tions. In this study, considering different traffic control scenarios, we examined the relationshipbetween traffic emissions resulting from children being driven to school and the pollutant dose expe-rienced by the children walking to school. A simulation-based framework was used to quantify thecombined effects of parents’ mode choice (either walk or drive) and traffic control measures (e.g.speed limit, and delay-based actuated signal controls) on traffic related pollutant concentration andthe dose experienced by children walking to school. The combined impact assessment showed thatthe effectiveness of emission reduction strategies around the school was found to vary dependingon the school location (high and low background traffic scenario), the proportion of children drivento school, and the traffic control condition. Results revealed the gross inequality of the impacts ofhigh car use, as the dose per child walking to school was significantly higher than that for a childdriven to school. For both school locations, reducing school-bound cars and controlling speed werefound to result in a decrease in PMx dose experienced by walkers. The results from this study providekey insights into school travel plan management strategies in different school locations.