A High Resolution Spatiotemporal Model for In-Vehicle Black Carbon Exposure: Quantifying the In-Vehicle Exposure Reduction Due to the Euro 5 Particulate Matter Standard Legislation

Abstract

Abstract:Several studies have shown that a significant amount of daily air pollution exposure is inhaled during trips. In this study, car drivers assessed their own black carbon exposure under real-life conditions (223 h of data from 2013). The spatiotemporal exposure of the car drivers is modeled using a data science approach, referred to as "microscopic land-use regression" (µLUR). In-vehicle exposure is highly dynamical and is strongly related to the local traffic dynamics. An extensive set of potential covariates was used to model the in-vehicle black carbon exposure in a temporal resolution of 10 s. Traffic was retrieved directly from traffic databases and indirectly by attributing the trips through a noise map as an alternative traffic source. Modeling by generalized additive models (GAM) shows non-linear effects for meteorology and diurnal traffic patterns. A fitted diurnal pattern explains indirectly the complex diurnal variability of the exposure due to the non-linear interaction between traffic density and distance to the preceding vehicles. Comparing the strength of direct traffic attribution and indirect noise map-based traffic attribution reveals the potential of noise maps as a proxy for traffic-related air pollution exposure. An external validation, based on a dataset gathered in 2010-2011, quantifies the exposure reduction inside the vehicles at 33% (mean) and 50% (median). The EU PM Euro 5 PM emission standard (in force since 2009) explains the largest part of the discrepancy between the measurement campaign in 2013 and the validation dataset. The µLUR methodology provides a high resolution, route-sensitive, seasonal and meteorology-sensitive personal exposure estimate for epidemiologists and policy makers.

Exposure to Air Pollution in Transport Microenvironments

“…For instance, Ref. [69] found that in-vehicle exposure is highly dynamic and related to local traffic dynamics. A fitted diurnal pattern indirectly explains the complex diurnal variability of the exposure due to the non-linear interaction between traffic density and distance to the preceding vehicles.…”

Carbonaceous Aerosols in the Atmosphere

“…This issue is analysed by Jereb et al [34], who quantify BC concentrations at chosen sites and cycling routes in Slovenia and conclude that exposure can indeed be reduced through adequate urban and traffic planning and management. Dekoninck & Int Panis [35], on the other hand, focus on the influence of transportation modes and assess the exposure of car drivers to BC with a microscopic land-use regression approach, taking into account regulatory interventions (e.g., the Euro 5 Particulate Matter Standard). This kind of exposure estimate is especially relevant for epidemiologists and policy makers.…”