The relationship between particle and culturable airborne bacteria concentrations in public transportation

Abstract

This study aims to determine the in-vehicle and outdoor culturable airborne bacteria concentration, fine particle (PM 2.5) concentration and particle number concentration for six size ranges (0.3-0.5 mm, >0.5-1.0 mm, >1.0-3.0 mm, >3.0-5.0 mm, >5.0-10 mm, and >10 mm) and to assess the relation between the culturable airborne bacteria and PM 2.5 concentrations in different public transport vehicles. The measurement campaign was conducted in the morning and evening onboard of the Metrobus, red-bus and outdoors. PM 2.5 concentrations in the Metrobus and red-bus were observed as 58.8 AE 10.2 mg/m 3 and 76.2 AE 30.9 mg/m 3 , respectively, and the outdoor value was about two times more. For both types of public transportation, the amount of internal environment particulate matter and the amount of external environment particulate matter displayed a high level of correlation (red-bus/outdoors, R ¼ 0.97; Metrobus/outdoors, R ¼ 0.88) with the particulate matter size. The concentration of Staphylococcus aureus correlated with PM 2.5 concentrations in the Metrobus and Staphylococcus spp. was found to be higher in in-vehicle. The number of commuters, vehicle ventilation type and outdoor air entering the vehicles probably caused the differences in in-vehicle culturable airborne bacteria and particle concentrations.

The Effects of COVID-19 Measures on Air Pollutant Concentrations at Urban and Traffic Sites in Istanbul

“…Although there has been research on the relationship between bacteria and particulate matter (Onat et al, 2017), there are limited studies on the relationship between viruses and air pollution. One such study found a significant positive correlation between the infection rate of respiratory syncytial virus and PM 2.5 (r = 0.45) and; PM 10 (r = 0.40) (Croft et al, 2019).…”

HVAC systems for environmental control to minimize the COVID-19 infection

“…Several investigations on transport microenvironments have found serious indoor environment quality (IEQ) Public vehicles Nine people on the bus were tested positive and J got on the bus after A got off 9 problems compared to outdoors. 37 The high density of crowd and relatively enclosed environment may account for the serious IEQ inside public vehicles. Hence, commuters' potential exposure to viral infection in such a restricted indoor environment could engender opportunity for transmission of the virus during epidemics.…”

Particulate matter air pollution from the city of Quito, Ecuador, activates inflammatory signaling pathways in vitro

“…PM has previously been shown to be associated with bacterial products. 3,4,42 The cell-surface receptor TLR2, dimerized with TLR1 or TLR6, recognizes lipoproteins and lipopeptides of the cell wall of Gram-positive bacteria, 43 as well as a diversity of molecules derived from Gram-negative bacteria, 44 fungi, 3,45 and protozoa. 46,47 To assess the ability of PM from Quito to activate the TLR2 signaling pathway, we stimulated TLR2-expressing luciferase reporter cells with PM 10 particles.…”