In-car and Near-road Exposure to PM2..

The current study aims to characterize the PM_2.5 and the equivalent black carbon (eBC) inside/outside vehicles (hereafter called "in/out-cabin") and near roadway, and to estimate their personal exposure to the driver himself as well as the school-aged children. Based on the DoseDEP of a mouse reaching the 90% polymorphonuclear leukocytes (PMNs90%) (Stoeger et al., 2006), the time (day) to reaching the PMNs_90% in the blood of a male resident who lives around the roadway was newly calculated. Five independent measurements of PM_2.5 and eBC were intensively taken in May 2019 using the monitors attached to the interior and exterior of the vehicle, respectively. In-cabin and out-cabin PM_2.5 on the course of driving measurement ranged from 29.4-47.4 µg/m3 with an average of 34.4 µg/m3 and 32.5-56.0 µg/m3 with an average of 45.6 µg/m3, respectively. The eBC in/out-cabin ratio during idling on a busy road ranged from 22% to 86% depending on the windows open/close and ventilation on/off. The in-cabin DosePM_2.5 (ng) for 30 seconds on the test driving route ranged from 166-240 ng with an average of 190.4 ng. The average in-school DosePM_2.5 (µg) for the schoolchild attending the school near a bus stop is 1.2 times higher than that of schoolchild attending the school away from a bus stop. The time (day) to reaching the PMNs90% due to DEP inhalation for the male resident who lives around the roadway was estimated as 113 days. [ABSTRACT FROM AUTHOR]