Unexpected changes in source apportioned results derived from different ambient VOC metrics.

Although most source apportionments of VOCs use mixing ratios, about 23 % of published studies use mass concentrations. Thus, systematically exploring the changes in VOC source apportioned results caused by metric differences is important to assess the differences in key precursor apportionment results given the observed increases in O pollution situation. Different monitoring instruments measured hourly VOC volumetric concentrations in three typical Chinese cities (i.

[Source Apportionment of Ambient VOCs in Qingdao Based on Photochemical Loss Correction].

Ozone was one of the major pollutants affecting the environmental air quality in China. The accurate apportionment of key sources and their contributions of ambient ozone and its precursor VOCs played an important role in the effective prevention and control of ozone pollution. Therefore, this study utilized the photochemical-age-based parameterization method to estimate the initial concentrations of ambient VOCs data collected from January 1 to February 28, 2021 in Jiaozhou, Qingdao and corrected the photochemical losses of ambient VOC species.

Source apportionment of consumed volatile organic compounds in the atmosphere.

Conventional source apportionments of ambient volatile organic compounds (VOCs) have been based on observed and initial concentrations after photochemical correction. However, these results have not been related to ozone (O) and secondary organic aerosol (SOA) formation. Thus, the apportioned contributions could not effectively support secondary pollution control development.

Changes in source apportioned VOCs during high O periods using initial VOC-concentration-dispersion normalized PMF.

Ambient volatile organic compounds (VOCs) concentrations are affected by emissions, dispersion, and chemistry. This work developed an initial concentration-dispersion normalized PMF (ICDN-PMF) to reflect the changes in source emissions. The effects of photochemical losses for VOC species were corrected by estimating the initial data, and then applying dispersion normalization to reduce the impacts of atmospheric dispersion.

[Chemical Characteristics and Source Apportionment for VOCs During the Ozone Pollution Episodes and Non-ozone Pollution Periods in Qingdao].

The ambient concentration of ozone is high in Qingdao, and ozone pollution episodes occur frequently in summer. The refined source apportionment of ambient volatile organic compounds (VOCs) and their ozone formation potential (OFP) during ozone pollution episodes and non-ozone pollution periods can play an important role in effectively reducing air ozone pollution in coastal cities and continuously improving ambient air quality. Therefore, this study applied the online VOCs monitoring data with hourly resolution in summer (from June to August) in 2020 in Qingdao to analyze the chemical characteristics of ambient VOCs during the ozone pollution episodes and non-ozone pollution periods and conducted the refined source apportionment of ambient VOCs and their OFP using a positive matrix factorization (PMF) model.

Chemical characteristics and sources of ambient PM in a harbor area: Quantification of health risks to workers from source-specific selected toxic elements.

Samples of ambient PM were collected in the Qingdao harbor area between 21 March and May 25, 2016, and analyzed to investigate the compositions and sources of PM and to assess source-specific selected toxic element health risks to workers via a combination of positive matrix factorization (PMF) and health risk (HR) assessment models. The mean concentration of PM in harbor area was 48 μg m with organic matter (OM) dominating its mass. Zn and V concentrations were significantly higher than the other selected toxic elements.