Monitoring fine and ultrafine particles in the atmosphere of a Southeast Chinese city

Abstract

There have been few studies on submicron particles in the atmosphere reported from developing countries. With rapid economic development, the size of the road vehicle fleet has increased dramatically in China. The increase in vehicle emissions has raised concerns about air quality, especially in the urban areas of this developing country. A model study was conducted in Hangzhou, a city in Southeast China, with the aim of characterizing the emission patterns of submicron particles ≤1.0 micron from on-road vehicles and the impact of vehicle density and speed on the concentrations of submicron particles in the atmosphere. Results showed that the average ultrafine particle (UFP) number concentration was 45 805 particles cm(-3) and the average mass concentration of particulate matter 1.0 (PM1.0) was 217 μg m(-3) during the survey period. Autoregressive Integrated Moving Average modelling results indicated that an increase of vehicle density and driving speed were positively correlated with the increase of UFP and PM1.0 concentrations (p < 0.05) in the atmosphere. Results from this study suggest that vehicle density and driving speed are significant predictors of submicron particle emissions. This study provides first hand information for future investigations on the submicron particle emissions in Hangzhou, a city with rapidly increasing vehicle numbers and for further investigations into a possible causal relationship between submicron particles and health effects on local residents.

Atmospheric Distribution of PAHs and Quinones in the Gas and PM1 Phases in the Guadalajara Metropolitan Area, Mexico: Sources and Health Risk

“…Barradas-Gimate et al [23] reported that in the GMA the 1,4-PQ in PM 2.5 is emitted mostly as product of diesel combustion, and is in good agreement with the observations in Grenoble, France, for primary emissions reported by Tomaz et al [22]. Furthermore, the correlation between ΣQuinones (p) and SO 2 of r = 0.77 may confirm that quinones have a primary origin, and suggests that submicron particles can be a better indicator for primary emissions than PM 2.5 [76]. The 1,4-NQ was correlated positively with the 5,12-NAQ in the particle phase (r = 0.75), which may arise from the role of the NQ as an intermediary in the formation of 5,12-NAQ through the Diels-Alder reaction [77].…”

Exposure characteristics of ferric oxide nanoparticles released during activities for manufacturing ferric oxide nanomaterials

“…The total NCs were determined using a P-TRAK ultrafine particle counter (Model 8525; TSI, Shoreview, MN). It is a portable condensation particle counter (CPC) that is used frequently to measure the particle NC of NP or ultrafine particles (Jian et al, 2011;Morawska et al, 2009). The counter, which was calibrated by the manufacturer, was set to zero daily prior to sampling.…”

Predicting submicron air pollution indicators: a machine learning approach

“…To address this gap, particularly in the context of a developing country, we prepared a dataset containing measurements of both traffic and weather variables, as well as PM1.0 and UFP levels, at a busy road in Hangzhou, China, a city witnessing a rapid increase in its vehicle eet. In previous work, we conducted Autoregressive Integrated Moving Average (ARIMA) regression analyses on this dataset, 20,21 revealing that both weather and traffic variables can inuence the PM1.0 and UFP levels. However, ARIMA and other regression models do not directly provide predictions about which levels of PM1.0 and UFP are considered too "high" in the atmosphere, and thus, further action is needed to control the pollution level.…”