Emission profiles, source identifications, and health risk of polycyclic aromatic hydrocarbons (PAHs) in a road tunnel located in Xi'an, China.

Understanding the sources and characteristics of PM-bound PAHs from traffic-related pollution can provide valuable data for mitigating air contamination from traffic in local urban regions. However, little information on PAHs is available regarding the typical arterial highway-Qinling Mountains No.1 tunnel in Xi'an.

Regional Transport of PM from Coal-Fired Power Plants in the Fenwei Plain, China.

The Fenwei Plain (FWP) remains one of the worst PM-polluted regions in China, although its air quality has improved in recent years. To evaluate the regional transport characteristics of PM emitted by coal-fired power plants in the FWP in wintertime, the primary PM, SO, and NOx emissions from coal-fired power plants with large units (≥300 MW) in 11 cities of the area in January 2019 were collected based on the Continuous Emission Monitoring System (CEMS). The spatial distribution and source contribution of primary and secondary PM concentrations were investigated using the Weather Research and Forecast (WRF) model and the California Puff (CALPUFF) model.

Spatial characteristics of VOCs and their ozone and secondary organic aerosol formation potentials in autumn and winter in the Guanzhong Plain, China.

As critical precursors of tropospheric ozone (O) and secondary organic aerosol (SOA), volatile organic compounds (VOCs) largely influence air quality in urban environments. In this study, measurements of 102 VOCs at all five major cities in the Guanzhong Plain (GZP) were conducted during Sep.09-Oct.

[Characteristics of VOCs and Formation Potentials of O and SOA in Autumn and Winter in Tongchuan, China].

Volatile organic compounds (VOCs) are the main precursors of tropospheric O and secondary organic aerosol (SOA), which can enhance atmospheric oxidation, promote the formation of secondary pollutants, and affect regional air quality and human health. In order to gain insights on VOCs characteristics and their potentials for O and SOA formation, the volume fraction of 102 VOCs in autumn and winter in the urban area of Tongchuan were monitored using the TH-300B online monitoring system. The maximum incremental reactivity (MIR) coefficient and the fractional aerosol coefficient (FAC) were used to estimate the ozone formation potential (OFP) and SOA formation potential (SOAFP), respectively.

VOCs characteristics and their ozone and SOA formation potentials in autumn and winter at Weinan, China.

Frequent ozone and fine particulate matter (PM) pollution have been occurring in the Guanzhong Plain in China. To effectively control the tropospheric ozone and PM pollution, this study performed measurements of 102 VOCs species from Sep.19-25 (autumn) and Nov.

Phthalates in house dust in Chinese urban residences: Concentrations, partition, origin and determinants.

Exposure to phthalates poses adverse health impacts to human beings. In this study, we analyzed 7 phthalates in dust samples, which were collected with vacuum cleaner from 40 to 31 residences in Beijing in summer and winter, respectively. The major phthalates (median concentration in the summer and winter, respectively) were DiBP (55 and 40 ng/mg), DnBP (99 and 30 ng/mg) and DEHP (795 and 335 ng/mg).

Chemical characterization of PM emitted from China IV and China V light-duty vehicles in China.

This study reported the emission factors (EFs) and detailed chemical compositions of PM collected from China IV and China V light-duty vehicles (LDVs) through dynamometer test. The China IV LDVs containing 4 gasoline vehicles (GVs) and 4 natural gas vehicles (NGVs) had port fuel injection (PFI) engines, while the China V LDVs included 2 GVs with PFI engines and 2 GVs with gasoline direct injection (GDI) engines. The average EFs of PM were 1.

Emission characteristics and ozone formation potentials of gaseous pollutants from in-use methanol-, CNG- and gasoline-fueled vehicles.

Alternative-fueled vehicles have been introduced to solve the problem of the energy crisis and address air pollution. However, typical pollutants (e.g.

Morphology and composition of particles emitted from conventional and alternative fuel vehicles.

Size, morphology, and composition of airborne particles strongly affect human health and visibility, precipitation, and the kinetic characteristics of particles. In this study, the morphology and chemical composition of particles emitted from conventional (diesel and gasoline) and alternative (CNG and methanol) fuel vehicles were characterized through scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX). The SEM images revealed that the size of primary particles (without agglomeration) was approximately 10 nm in the exhaust from all the tested vehicles.

Scenario analysis of vehicular emission abatement procedures in Xi'an, China.

Vehicular emissions contribute significantly to air pollution, and the number of vehicles in use is continuing to rise. Policymakers thus need to formulate vehicular emission reduction policies to improve urban air-quality. This study used different vehicle control scenarios to predict the associated potential of mitigating carbon monoxide (CO), volatile organic compounds (VOCs), nitrogen oxide (NO), particulate matter with an aerodynamic diameter less than 2.

Airborne phthalates in indoor environment: Partition state and influential built environmental conditions.

Exposure to phthalates has recently become a major public health concern. The information of indoor airborne phthalates and their air-particle partition in real indoor environmental condition is still limited. In this study, the gas- and PM-concentrations of 7 phthalates in 40 residences were concurrently measured in summer and winter.

Chemical characterisation of PM emitted from motor vehicles powered by diesel, gasoline, natural gas and methanol fuel.

Vehicle emissions are affected by factors such as vehicle type, fuel quality, and engine repair. Therefore, mobile source profiles should be established based on a characteristic fleet for a specific region. This study characterised the chemical composition of PM emitted from motor vehicles that are commonly used in Xi'an through dynamometer tests.

Characteristics of ambient bioaerosols during haze episodes in China: A review.

Frequent low visibility, haze pollution caused by heavy fine particulate matter (PM) loading, has been entailing significant environmental issues and health risks in China since 2013. A substantial fraction of bioaerosols was observed in PM (1.5-15%) during haze periods with intensive pollution.

[Air Pollution Characteristics and Jogger Inhalation Exposure in Typical Running Area of Beijing].

To investigate the exposure to major air pollutants of runners while running in Beijing, the concentrations of PM, CO, O, and NO were constantly monitored at typical park running areas (Tiantan Park and Olympic Sports Center), roadside running areas (Qianmen East Street and Yongding Inner Street), and a background area (Dinglin) during April, June, and October of 2016 and in January 2017. The concentration variation characteristics for the pollutants in different areas and at different times were analyzed. Using a numerical model of human respiratory exposure, 102 joggers were studied, as was the temporal-spatial variation of inhalation dose of pollutants.

Bacterial community structure in atmospheric particulate matters of different sizes during the haze days in Xi'an, China.

Serious air pollution events have frequently occurred in China associated with the acceleration of urbanization and industrialization in recent years. Exposure to atmospheric particulate matter (PM) of high concentration can lead to adverse effects on human health. Airborne bacteria are important constituents of microbial aerosols and contain lots of pathogens.

Emission inventory estimation of an intercity bus terminal.

Intercity bus terminals are hotspots of air pollution due to concentrated activities of diesel buses. In order to evaluate the bus terminals' impact on air quality, it is necessary to estimate the associated mobile emission inventories. Since the vehicles' operating condition at the bus terminal varies significantly, conventional calculation of the emissions based on average emission factors suffers the loss of accuracy.