In-train particulate matter (PM₁₀ and PM_2.5) concentrations: Level, source, composition, mitigation measures and health risk effect – A systematic literature review

Abstract

Exposure of commuters to pollutants on trains has been an essential topic of discussion in recent years due to its health implications. This review summarizes literature that measures particulate matter (PM) in trains to understand the concentration levels and health effects caused due to exposure. The databases searched were Scopus, Web of Science (WOS) and Google Scholar. Articles, conference papers and textbooks written in English, measuring PM in train carriages and published between 1998 and 2022 were selected for this review. Out of the 3247 articles identified, only 73 were included in this study. 15/20 articles agreed that concentration is significant at the underground segment by a factor of 7 than the counterpart above/ground levels. The review observed that 80% of the publication of in-train concentrations of PM10 and PM2.5 were above the WHO standard. In-train PM2.5 concentration ranges from 2 μgm−3 to 563 μgm−3, and in-train PM10 concentration ranges from 6 μgm−3 to 997 μgm−3. People’s activities, mechanical movement of train parts, train operation conditions and local emissions were the primary source of PM. Future research should focus on health damage due to PM exposure and the effect of the filtration system on PM levels in trains.

The influence of near-wall heat sources with different configurations on particle deposition in a small-scale chamber

“…The increase in the temperature of the near-wall heat source led to an increase in particle deposition. (3) The increase in the distance from the near-wall heat source has led to a decrease in the effect of the nearwall heat source on particle deposition. (4) The particle deposition increased obviously with the increasing air velocity in the chamber.…”

“…A silicone pipe of length 0.35 m located 0.2 m above the geometric centre of the back wall of the chamber was used as the entrance of particles into the chamber. Solutions of monodisperse styrene microspheres with a density of 1.064 g/cm 3 and diameters of 0.275, 0.4, 0.55, 0.8, 1.0, 1.3, 1.5 and 2.0 μm in deionized water were used in each measurement. The volume of the monodisperse styrene microspheres solutions was 10 mL, and the content of sodium azide and solid content in the solutions were 0.05% and 2.5% w/v, respectively.…”

“…2 Furthermore, it can cause abnormal symptoms and diseases related to the respiratory system, nervous system and immune system and increase the fatality rate. 3,4 In addition to the threat posed by suspended particles, particles deposited on surfaces may also lead to adverse consequences. Particle deposition can cause serious accidents in electronic manufacturing, equipment operation, medical industry, aerospace and other fields.…”

Navigating dust storms and urban living: an analysis of particulate matter infiltration in Dubai’s residences

“…The floor plan thus offers invaluable insights into the potential regions of PM concentration and its relation to architectural features Figure 3. The targeted building is positioned adjacent to a bustling 14-lane Sheikh Zayed Road, implying that the exterior concentration of PM is expected to be substantial, owing to the continuous vehicular traffic outside commuting hours (Azimi et al, 2018b;Otuyo et al, 2023). The 14-lane thoroughfare runs parallel to the southern side of the apartment complex, with an approximate distance of 20 m separating the two.…”