Determinants of in-home personal exposure to black carbon: the MobiliSense sensor-based study

Past studies have investigated black carbon (BC) exposure during daily travels and often referred to it as individuals' daily BC exposure, while people spend most of their time indoors. The aim of this study was to investigate the determinants of in-home BC exposure in Grand Paris, France, using data from the MobiliSense cohort. The personal BC concentration of 278 participants was measured continuously at a 10-second resolution with a MicroAethalometer device (MicroAeth AE51) strapped on their shoulder for 4 days. We applied a multilevel model with a random intercept at the household level, since more than one individuals from the same house were participating in the study, to predict the hourly in-home BC concentration. The use of home appliances and the characteristics of the dwelling, along with outdoor air pollution concentrations, were modelled as predictors. Our findings suggest that some heating systems, such as open fireplaces and stoves using woods, and outdoor pollutants, were predictors of in-home BC concentration. Our study suggests that in-home pollution can be reduced by improving home features, such as heating systems, or by reducing the infiltration of outdoor air pollutants into indoor microenvironment either by using air filters or redesigning the ventilation system.