Personal Exposure to PM2.5 in the Megacity of Mexico: A Multi-Mode Transport Study

Atmosphere

Ulises Diego-Ayala¹  Juan C. Zavala-Reyes²  Arón Jazcilevich²  Iván Y. Hernández-Paniagua²  Luis G. Ruiz-Suarez²  Gema L. Andraca-Ayala²  Irma Rosas-Pérez²  Laura Gochicoa-Rangel³  Silvia Cid-Juárez³  Luis Torre-Bouscoulet³ 

[1] Arian International Projects, c/Baldiri Reixach, 4, 08028 Barcelona, Spain;Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de Mexico, Circuito de la Investigación Científica S/N, Ciudad Universitaria, Coyoacán, 04510 Ciudad de Mexico, Mexico;Department of Respiratory Physiology, National Institute of Respiratory Diseases Ismael Cosío Villegas, Calzada de Tlalpan 4502, Col. Sección XVI, Tlalpan, 14080 Mexico City, Mexico;

关键词: air quality;    cyclists;    inhalation;    pedestrians;    vehicular emissions;   

DOI  :  10.3390/atmos9020057

来源: DOAJ

【 摘 要 】

Recurrent personal exposure to ambient PM2.5 is associated with adverse human health effects, in particular on the respiratory and cardiovascular systems. Here, we present an assessment of personal exposure and inhalation of PM2.5 for five modes of transport (walking, cycling, public bus (trolleybus and diesel bus), conventional car (CC) and hybrid-electric car (HEC)) and two routes of similar distance, along a major road in the Mexico City metropolitan area (MCMA). Arithmetic average exposure concentrations ranged from 16.5 ± 6.5 µg m−3 for walking to 81.7 ± 9.1 µg m−3 for cycling (henceforth shown as average ±1 SD), with no significant differences with geometric averages. The maximum exposure concentration of 110.9 µg m−3 was observed for the conventional car. The highest exposure concentrations depended on route and the mode of transport, being observed for cycling and walking. The PM2.5 measurements showed large spatial heterogeneity in the exposure levels for walking and cycling, while public buses and private transport showed less spatial heterogeneity. The greatest peaks in PM2.5 coincided with 4-way intersections for all modes of transport, being positively influenced by traffic density. The mass of PM2.5 inhaled depended mostly on the mode of transport, and ranged between 1.0 ± 0.3 and 30.1 ± 14.2 µg km−1 for the HEC and bicycle, respectively. Local area PM2.5 increments identified as ‘residuals’ after subtraction of data recorded at the closest fixed monitoring site from exposure concentrations along the studied road suggested that inhalation for bicycle and diesel buses is strongly influenced by vehicular emissions. Residuals estimated for the trolleybus, CC and HEC confirmed a lower inhalation than for the other modes of transport evaluated due to protection by the cabin.

【 授权许可】

Unknown