tetano
Editor, Senior Moderator
Sci Total Environ
. 2021 Mar 19;781:146618.
doi: 10.1016/j.scitotenv.2021.146618. Online ahead of print.
Road traffic and air pollution: Evidence from a nationwide traffic control during coronavirus disease 2019 outbreak
Chengyong Jia[SUP] 1 [/SUP], Wending Li[SUP] 1 [/SUP], Tangchun Wu[SUP] 1 [/SUP], Meian He[SUP] 2 [/SUP]
Affiliations
Abstract
Existing estimations of air pollution from automobile sources are based on either experiments or small-scale governmental interventions. China's nationwide traffic control during the coronavirus disease 2019 outbreak provided us a unique opportunity to assess the direct dose-effect relationship between vehicle density and air pollution. We found that, during the coronavirus disease 2019 outbreak, the nationwide reduced air pollution (except for O[SUB]3[/SUB]) could be largely explained by traffic control measures. During the traffic control period, every doubling of vehicle density was associated with a decrease of 4.2 (2.0, 6.4) ?g/m[SUP]3[/SUP] in PM[SUB]2.5[/SUB], 5.5 (2.9, 8.1) ?g/m[SUP]3[/SUP] in PM[SUB]10[/SUB], 1.5 (0.9, 2.0) ?g/m[SUP]3[/SUP] in NO[SUB]2[/SUB], and 0.04 (0.02, 0.07) mg/m[SUP]3[/SUP] in CO comparing cities with different vehicle densities. Similarly, for every 10% increase in the truck proportion, PM[SUB]2.5[/SUB] decreased by 12.3 (4.1, 20.6) ?g/m[SUP]3[/SUP], PM[SUB]10[/SUB] decreased by 14.3 (4.6, 23.9) ?g/m[SUP]3[/SUP], and CO decreased by 0.14 (0.05, 0.23) mg/m[SUP]3[/SUP]. Moreover, the associations between vehicle density and reduction in PM[SUB]2.5[/SUB], PM[SUB]10[/SUB], and CO during the traffic control period were stronger and showed near-complete linearity in cities with low green coverage rate (All P < 0.05 for interaction). According to our estimation, PM[SUB]2.5[/SUB] emissions from every doubling of vehicle density can lead to over 8000 excess deaths per year, 66% of which were caused by cardiopulmonary diseases. This natural experiment study is the first to observe the dose-effect relationship between on-road traffic and traffic-generated air pollution, as well as the mitigating effect of urban greening. Findings provide key evidence to the assessment and control of traffic-generated air pollution and its public health impact.
Keywords: Air pollution; COVID-19; Intervention; Mortality; Traffic; Urban greening.
. 2021 Mar 19;781:146618.
doi: 10.1016/j.scitotenv.2021.146618. Online ahead of print.
Road traffic and air pollution: Evidence from a nationwide traffic control during coronavirus disease 2019 outbreak
Chengyong Jia[SUP] 1 [/SUP], Wending Li[SUP] 1 [/SUP], Tangchun Wu[SUP] 1 [/SUP], Meian He[SUP] 2 [/SUP]
Affiliations
- PMID: 33780836
- DOI: 10.1016/j.scitotenv.2021.146618
Abstract
Existing estimations of air pollution from automobile sources are based on either experiments or small-scale governmental interventions. China's nationwide traffic control during the coronavirus disease 2019 outbreak provided us a unique opportunity to assess the direct dose-effect relationship between vehicle density and air pollution. We found that, during the coronavirus disease 2019 outbreak, the nationwide reduced air pollution (except for O[SUB]3[/SUB]) could be largely explained by traffic control measures. During the traffic control period, every doubling of vehicle density was associated with a decrease of 4.2 (2.0, 6.4) ?g/m[SUP]3[/SUP] in PM[SUB]2.5[/SUB], 5.5 (2.9, 8.1) ?g/m[SUP]3[/SUP] in PM[SUB]10[/SUB], 1.5 (0.9, 2.0) ?g/m[SUP]3[/SUP] in NO[SUB]2[/SUB], and 0.04 (0.02, 0.07) mg/m[SUP]3[/SUP] in CO comparing cities with different vehicle densities. Similarly, for every 10% increase in the truck proportion, PM[SUB]2.5[/SUB] decreased by 12.3 (4.1, 20.6) ?g/m[SUP]3[/SUP], PM[SUB]10[/SUB] decreased by 14.3 (4.6, 23.9) ?g/m[SUP]3[/SUP], and CO decreased by 0.14 (0.05, 0.23) mg/m[SUP]3[/SUP]. Moreover, the associations between vehicle density and reduction in PM[SUB]2.5[/SUB], PM[SUB]10[/SUB], and CO during the traffic control period were stronger and showed near-complete linearity in cities with low green coverage rate (All P < 0.05 for interaction). According to our estimation, PM[SUB]2.5[/SUB] emissions from every doubling of vehicle density can lead to over 8000 excess deaths per year, 66% of which were caused by cardiopulmonary diseases. This natural experiment study is the first to observe the dose-effect relationship between on-road traffic and traffic-generated air pollution, as well as the mitigating effect of urban greening. Findings provide key evidence to the assessment and control of traffic-generated air pollution and its public health impact.
Keywords: Air pollution; COVID-19; Intervention; Mortality; Traffic; Urban greening.