Particulate air pollution and noise: Assessing commuter exposure in Africa's most populous city. (June 2018)

• Record Type: Journal Article
• Authors: Okokon, Enembe O.; Taimisto, Pekka; Turunen, Anu W.; Amoda, Olanrewaju A.; Fasasi, Abolaji E.; Adeyemi, Lewis Gregory; Juutilainen, Jukka; Lanki, Timo
• Is Part Of: Journal of transport & health. Volume 9(2018)
• Page Start: 150
• Page End: 160
• Publication Date: 2018-06
• Subjects: AC Air-conditioning -- BC Black carbon -- CBD Central business district -- CV Coefficient of variation -- dB (A) A-weighted Decibels -- PM Particulate Matter -- PM2.5 Particulate matter 2.5 micrometres or less -- PM10 Particulate matter 10 micrometres or less -- PM10-2.5 Particulate Matter with diameter between 2.5 and 10 micrometres (coarse particles) -- PNC Particle number concentration -- pc Particles -- UFP Ultrafine particles -- µm Micrometre -- µg/m3 Microgram per cubic metre; Road traffic -- exposure -- particulates -- black carbon -- noise -- transport mode; Transportation -- Health aspects -- Periodicals; Transportation -- Periodicals; Public Health -- Periodicals; Noise, Transportation -- Periodicals; Air Pollutants -- Periodicals; 388
• DOI: 10.1016/j.jth.2018.04.003
• Languages: English
• ISSNs: 2214-1405

Abstract

Abstract: Africa is rapidly urbanising, consequently, there is the growing relevance of daily air pollution and noise exposure during urban commuting. Yet, little is known about commuter exposures in Africa. Lagos has a population in excess of nine million people, and approximately 788, 000 registered motor vehicles. We monitored exposures of commuters within the Lagos metropolis to various size fractions of particulate air pollution, black carbon, and noise while traveling by car (taxi), microbus and larger bus with an aim to determine exposure levels and compare between modes. We conducted, altogether, 139 trips on nine designated commuting routes. The highest exposures were recorded when vehicle windows were open and air-conditioners turned off. For example, mean gravimetric PM10 levels of 364, 489 and 280 µg/m 3, and mean particle number count (PNC) levels of 92, 52 and 27 (x 10 3 pc /cm 3 ) were recorded in the car, microbus and larger bus, respectively. With the closed window setting, considerable reduction in particulate matter (PM) concentration was recorded on larger buses compared with cars. The highest mean (85 dB(A)) and highest mean 99 th percentile (92 dB(A)) noise levels were obtained during trips on microbuses when windows were left open. This study observed remarkably high particulate air pollution and noise exposures during commuting in the major African city. A major shift to modern mass transportation systems would limit commuter exposure. Highlights: Particulate matter (PM) and noise exposures estimated in three transport modes during Harmattan season. Overall exposures to PM, black carbon (BC) and noise were high in all transport modes and settings. Exposure levels exceed those reported in similar studies from Europe and Asia. Larger bus commuters had lower PM exposures than cars but higher noise exposures. Proper vehicle maintenance and designated lanes can lessen commuter PM exposures.