High-resolution sampling and analysis of ambient particulate matter in the Pearl River Delta region of southern China: source apportionment and health risk implications

Abstract

Abstract. Hazardous air pollutants, such as trace elements in particulate matter (PM), are known or highly suspected to cause detrimental effects on human health. To understand the sources and associated risks of PM to human health, hourly time-integrated major trace elements in sizesegregated coarse (PM 2.5-10 ) and fine (PM 2.5 ) particulate matter were collected at the industrial city of Foshan in the Pearl River Delta region, China. Receptor modeling of the data set by positive matrix factorization (PMF) was used to identify six sources contributing to PM 2.5 and PM 10 concentrations at the site. Dominant sources included industrial coal combustion, secondary inorganic aerosol, motor vehicles and construction dust along with two intermittent sources (biomass combustion and marine aerosol). The biomass combustion source was found to be a significant contributor to peak PM 2.5 episodes along with motor vehicles and industrial coal combustion. Conditional probability function (CPF) analysis was applied to estimate the source locations using the PMF-resolved source contribution coupled with the surface wind direction data. Health exposure risk of hazardous trace elements (Pb, As, Si, Cr, Mn and Ni) and source-specific values were estimated. The total hazard quotient (HQ) of PM 2.5 was 2.09, higher than the acceptable limit (HQ = 1). The total carcinogenic risk (CR) was 3.37 × 10 −3 for PM 2.5 , which was 3 times higher than the least stringent limit (1.0 × 10 −4 ). Among the selected trace elements, As and Pb posed the highest non-carcinogenic and carcinogenic risks to human health, respectively. In addition, our results show that the industrial coal combustion source is the dominant non-carcinogenic and carcinogenic risk contributor, highlighting the need for stringent control of this source. This study provides new insight for policy makers to prioritize sources in air quality management and health risk reduction.

The regional nature of nitrate-dominant haze pollution during autumn over the Pearl River Delta area

“…Its rapid urbanization and industrialization and concurrent population increase are leading to enhanced anthropogenic emissions. Photochemical smog and particle pollution are frequent in this region (Liu et al 2014;Zou et al 2015;Zhou et al 2018). Studies have reported that primary or anthropogenic emissions from industry, biomass burning, traffic, and coal combustion act as significant contributors to local particle emissions (Pan et al 2016a;Fu and Chen 2017).…”

“…Furthermore, the accumulation of traffic emissions has frequently been reported as a primary cause of pollution events in urban areas of the PRD (Qin et al 2017). In contrast, biomass burning, which is extremely rare at most times of the year, nonetheless plays more important roles in particle concentrations and pollution events in the PRD in harvest season (Zhang et al 2010;Tao et al 2014;Wang et al 2016;Liu et al 2018;Zhou et al 2018). Influenced by multiple atmospheric conditions such as relative humidity and temperature, secondary processes, mainly generating sulfates, nitrates, and secondary organic aerosols, also substantially contribute to ambient aerosol concentrations (Hua et al 2015;.…”

“…Despite many studies having been conducted in the PRD region to characterize local particle pollution and further establish environmental policies, existing knowledge of the detailed sources, atmospheric processes, and chemical mechanisms of ambient aerosols is still far from enough Zhou et al 2018). Measurements have usually focused on pollution characteristics at a single site, failing to gain an overall insight into the regional air condition in the PRD region.…”

Source apportionment of highly time resolved trace elements during a firework episode from a rural freeway site in Switzerland

“…Traffic-derived PM has high risk of respiratory illness, asthma and cardiovascular diseases, resulting in increased rate in mortality (Kelly and Fussell, 2011). Traffic-related PM is emitted mainly as exhaust emissions (tailpipe exhaust from gasoline and diesel engines) and non-exhaust emissions (resuspension of road dust and brake and tire wear emissions) (Lawrence et al, 2013;Lin et al, 2015;Thorpe and Harrison, 2008;Zhou et al, 2018;Grigoratos and Martini, 2015;Amato et al, 2014b;Bukowiecki et al, 2010). Exhaust emissions are predominantly in the fine fraction of PM whereas non-exhaust emissions contribute mostly to the coarse fraction (Amato et al, 2011;Thorpe and Harrison, 2008).…”

“…It has been reported that asphalt pavement-induced particles were characterized mainly by high concentrations of Cu, Cr, Ni, As and Pb (Yu, 2013) as well as Ca, Si, Mg, Al, Fe, P, S, Cl, K, V, Mn, Na (Fullova et al, 2017). Therefore, it is important to monitor traffic emissions for health risk assessment, the study of which relies heavily on the source apportionment (SA) of PM using chemically speciated data (Zhou et al, 2018).…”