Traffic is a main source of air pollutants in urban areas and consequently daily peak exposures tend to occur during commuting.Personal exposure to particulate matter(PM)was monitored while cycling and travelling by b...Traffic is a main source of air pollutants in urban areas and consequently daily peak exposures tend to occur during commuting.Personal exposure to particulate matter(PM)was monitored while cycling and travelling by bus,car and metro along an assigned route in Lisbon(Portugal),focusing on PM_(2.5) and PM_(1)0(PM with aerodynamic diameter<2.5 and 10μm,respectively)mass concentrations and their chemical composition.In vehicles,the indoor-outdoor interplay was also evaluated.The PM_(2.5) mean concentrations were 28±5,31±9,34±9 and 38±21μg/m 3 for bus,bicycle,car and metro modes,respectively.Black carbon concentrations when travelling by car were 1.4 to 2.0 times higher than in the other transport modes due to the closer proximity to exhaust emissions.There are marked differences in PM chemical composition depending on transport mode.In particular,Fe was the most abundant component of metro PM,derived from abrasion of rail-wheel-brake interfaces.Enhanced concentrations of Zn and Cu in cars and buses were related with brake and tyre wear particles,which can penetrate into the vehicles.In the motorised transport modes,Fe,Zn,Cu,Ni and K were correlated,evidencing their common traffic-related source.On average,the highest inhaled dose of PM_(2.5) was observed while cycling(55μg),and the lowest in car travels(17μg).Cyclists inhaled higher doses of PM_(2.5) due to both higher inhalation rates and longer journey times,with a clear enrichment in mineral elements.The presented results evidence the importance of considering the transport mode in exposure assessment studies.展开更多
基金European Union through the project LIFE Index-Air(LIFE15 ENV/PT/000674)supported by Portuguese Foundation for Science and Technology(FCT)through the projects Expo LIS(LISBOA-01-0145-FEDER-032088)and UID/Multi/04349/2013,the contract CEECIND/04228/2018 and the Ph D grants SFRH/BD/129149/2017 and SFRH/BD/147074/2019。
文摘Traffic is a main source of air pollutants in urban areas and consequently daily peak exposures tend to occur during commuting.Personal exposure to particulate matter(PM)was monitored while cycling and travelling by bus,car and metro along an assigned route in Lisbon(Portugal),focusing on PM_(2.5) and PM_(1)0(PM with aerodynamic diameter<2.5 and 10μm,respectively)mass concentrations and their chemical composition.In vehicles,the indoor-outdoor interplay was also evaluated.The PM_(2.5) mean concentrations were 28±5,31±9,34±9 and 38±21μg/m 3 for bus,bicycle,car and metro modes,respectively.Black carbon concentrations when travelling by car were 1.4 to 2.0 times higher than in the other transport modes due to the closer proximity to exhaust emissions.There are marked differences in PM chemical composition depending on transport mode.In particular,Fe was the most abundant component of metro PM,derived from abrasion of rail-wheel-brake interfaces.Enhanced concentrations of Zn and Cu in cars and buses were related with brake and tyre wear particles,which can penetrate into the vehicles.In the motorised transport modes,Fe,Zn,Cu,Ni and K were correlated,evidencing their common traffic-related source.On average,the highest inhaled dose of PM_(2.5) was observed while cycling(55μg),and the lowest in car travels(17μg).Cyclists inhaled higher doses of PM_(2.5) due to both higher inhalation rates and longer journey times,with a clear enrichment in mineral elements.The presented results evidence the importance of considering the transport mode in exposure assessment studies.
