A method was developed for the simultaneous determination of thirteen amines including seven aliphatic amines, two heterocyclic amines and four aromatic amines associated with atmospheric particulate matter (PM) by gas chromatography-mass spectrometry (GC-MS). PM samples were ultrasonically extracted with ultrapure water, and derivatized by benzenesulfonyl chloride (BSC) under alkaline condition. The derivatives were extracted with dichloromethane and then detected by GC-MS with DB-5MS chromatographic column. The method detection limits (S/N = 3) and quantitative limits (S/N = 10) for thirteen amines were between 0.00008–0.01695 μg mL−1 and 0.00026–0.0565 μg mL−1, respectively. Good linear correlations were obtained for all the thirteen amines with the linear relative coefficients between 0.9903–0.9996. The recoveries of thirteen amines were in the range of 54.4%–159.7% except for methylamine and benzylamine at spiked level of 1.0 μg mL−1, and the reproducibility expressed as relative standard deviations (RSDs) of thirteen amines were less than 30%, which indicated that the method had high precision and good reliability. PM2.5 samples were collected in Guangzhou city, China, and nine amines were detected by our established method. Methylamine, dimethylamine and butylamine accounted for 90% of the total nine amines which suggested that they were main amine components in PM2.5, while propylamine exhibited the lowest level with the concentration less than 1.0 ng m−3.A method was developed for the determination of thirteen amines including seven aliphatic amines, two heterocyclic amines and four aromatic amines in atmospheric particulate matter by GC-MS. The samples were ultrasonically extracted with ultra-pure water and derivatized with benzenesulfonyl chloride under alkaline condition. The derivatives were extracted with dichloromethane and then detected by GC-MS with DB-5MS column.Download high-res image (78KB)Download full-size image

•Size-resolved particulate amines were first characterized in the Pearl River Delta region, China.•ƩAmines exhibited a predominant occurrence in the size fraction between 0.49 and 0.95 μm.•The contribution of amines-N to WSON decreased with increasing particle size.•The Ʃamines/ammonium molar ratio ranged from 0.0068 to 0.0107 in PM1.5 with a maximum at < 0.49 μm.•Dry deposition fluxes of amines were dominated by fine particles within PM10.Size-segregated PM10 samples were collected in Guangzhou, China during autumn of 2014. Nine amines, including seven aliphatic amines and two heterocyclic amines, were detected using a gas chromatography-mass spectrometer after derivatization by benzenesulfonyl chloride. The total concentration of the nine amines (Ʃamines) was 79.6–140.9 ng m−3 in PM10. The most abundant species was methylamine (MA), which had a concentration of 29.2–70.1 ng m−3. MA, dimethylamine (DMA), diethylamine (DEA) and dibutylamine (DBA) were the predominant amines in the samples and accounted for approximately 80% of Ʃamines in each size segment. Two heterocyclic amines, pyrrolidine (PYR) and morpholine (MOR), were detected in all samples and had average concentrations of 1.14 ± 0.37 and 1.89 ± 0.64 ng m−3, respectively, in particles with aerodynamic diameters < 3 μm. More than 80% of Ʃamines were found in particles with diameters <1.5 μm, indicating that amines are mainly enriched in fine particles. All amines exhibited a bimodal distribution with a fine mode at 0.49–1.5 μm and a coarse mode at 7.2–10 μm. The maximum contributions of amines to particles (0.21%) and amines-N to water-soluble organic nitrogen (WSON) (3.1%) were found at the sizes < 0.49 μm. The maximum contribution of amines-C to water-soluble organic carbon (WSOC) was 1.6% over the size range of 0.95–1.5 μm. The molar ratio of Ʃamines to ammonium ranged from 0.0068 to 0.0107 in particles with diameters <1.5 μm, and the maximum ratio occurred in the smallest particles (diameter< 0.49 μm). The average dry deposition flux and velocity of Ʃamines in PM10 were 7.9 ± 1.6 μg m−2 d−1 and 0.084 ± 0.0021 cm s−1, respectively. The results of this study provide essential information on the contribution of amines to secondary organic aerosols and dry removal mechanisms in urban areas.

Coal combustion is one of the most significant sources of air pollution in China. In this study, emission factors (EFs) of 15 polycyclic aromatic hydrocarbons (PAHs), 26 nitrated PAHs (NPAHs) and 6 oxygenated PAHs (OPAHs) were determined in five different coals with different geological maturity (vitrinite reflectance RO = 0.77–1.88%) burned in the form of honeycomb briquettes. The total EFs ranged from 9.82 to 215 mg kg–1 for PAHs, 0.14 to 1.88 mg kg–1 for NPAHs and 4.47 to 20.8 mg kg–1 for OPAHs. Measured EFs and gas-particle partitioning varied depending on the geological maturity. The lowest EFs were found in anthracite. The proportion of PAHs, NPAHs and OPAHs in gaseous phase increasing with increased geological maturity. The coal with higher geological maturity produced more 3-ring PAHs. On the basis of the statistical analysis for the residential sector of China in 2008, PAHs, NPAHs and OPAHs emitted from residential honeycomb coal briquettes were 4.36 Gg, 0.03 Gg and 0.47 Gg in 2007, respectively. By 2020, the emission would decrease to 2.18 Gg, 0.02 Gg and 0.24 Gg for PAHs, NPAHs and OPAHs due to the increasing usage of new energy resources. If only anthracite is used as the residential coal, 93% PAHs, 87% NPAHs and 71% OPAHs would be reduced in 2020.

Heavy metals and persistent organic pollutants polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were analyzed in 34 surface soil samples collected from farmland and 7 soil or dust samples collected from the workshops in South China, where e-waste was dismantled using primitive techniques. The results show that Cd, Cu and Hg were the most abundant metals, in particular Cd pollution was serious in farmland soils, and the median concentrations in farmland soils were beyond the environmental quality standard for soils (China Grade II). A correlation between Cd, Cu, Zn, Pb and PCBs or PBDEs was significant indicating similar sources. Among the PCB congeners, high relative similarity was observed between the e-waste dump site soil (EW1) and Aroclor 1254, implying that the technical product Aroclor 1254 was one of the major sources of PCB contamination. High concentrations of PCBs in workshop dusts (D2 and D3) (1958 and 1675 μg kg−1) demonstrated that the workshops dismantling electrical wires and cables, electrical motors, compressors and aluminum apparatus containing PCBs in lubricants represent strong PCB emission sources to this area. Principal component analysis (PCA) and PBDE homologue patterns verify that farmland soils surrounding the e-waste recycling sites were enriched with lower brominated congeners, and the major source of PBDEs in dust samples might potentially be associated with the extensive use of deca-mix technical products as a flame retardant. The difference between e-waste soils, dusts and farmland soils can be observed in the PCA score plot of PCBs and PBDEs, and E-waste soils and dusts exhibited more diversity than farmland soils. Furthermore, a prediction of the particular kinds of pollution from different recycling activities through the analysis of each contamination and the connections between them was investigated.

Daytime and nighttime PM2.5 samples were collected between August 5 and 16, 2009 and between January 24 and February 4, 2010 in an industrial complex site (site A) and an electronic waste recycling site (site B) to determine the seasonal and diurnal variations of 19 individual polycyclic aromatic hydrocarbons (PAHs) with molecular weight 302 (MW302) including four highly carcinogenic dibenzopyrene (DBP) isomers dibenzo[a,l]pyrene (DBalP), dibenzo[a,e]pyrene (DBaeP), dibenzo[a,i]pyrene (DBaiP), and dibenzo[a,h]pyrene (DBahP). This is the first report on DBP isomers in air particles from South China. The total concentration of PAH MW302 isomers ranged from 1.65 to 3.60 ng m−3 in summer and 3.82 to 9.81 ng m−3 in winter. The strongest peaks in the chromatograms of the MW302 isomers were naphtha[2,1-a]pyrene (N21aP), dibenzo[j,l]fluoranthene (DBjlF), naphtha[1,2-b]fluoranthene (N12bF), naphtha[1,2-k]fluoranthene (N12kF) and dibenzo[a,e]fluoranthene (DBaeF), constituting 52.0 to 55.4% of the total MW302 isomers. All the MW302 isomers showed notable seasonal variations. Most of the MW302 isomers in site B showed distinctive diurnal variations with higher concentrations occurring in the night. Taking into account both concentration and potency equivalence factors (PEFs), the strongest carcinogen in the analyzed samples was DBaiP, and the ratios of sum carcinogenic potency of four highly carcinogenic DBP isomers to benzo[a]pyrene (BaP) was about 0.94 in winter to 1.89 in summer, indicating the importance of DBP isomers for the risk assessment. Health risk assessment indicated that on average, 1 in 100000 residents in the two industrial sites may have an increased risk of cancer due to PAH exposure.

The organic constituents and distributions of molecular markers emitted from a residential coal-stove burning honeycomb coal briquettes were determined in this study. The major organic components emitted directly in smoke particles were polycyclic aromatic hydrocarbons (PAHs), with abundant hydroxy-polycyclic aromatic hydrocarbons (OH-PAHs), i.e., thermally altered derivative compounds from coal combustion, UCM (unresolved complex mixture of branched and cyclic compounds), n-alkanes and n-alkanoic acids. Other compounds present as minor components included n-alkenes, phenols, alkylbenzenes and n-alkanols. The distributions of the organic compounds in the coal smoke samples were highly variable and dependent on combustion temperature, flame aeration, fire duration, and coal rank. Coal smoke emissions may be identified by some indicators including: (1) presence of hydroxy-PAHs, (2) the decrease in carbon preference index (CPI) of n-alkanoic acids with increasing rank, (3) the decrease of the ratios of 17α(H),21β(H)-29-norhopane to 22R-17α(H),21β(H)-homohopane and 17α(H),21β(H)-29-norhopane to 17α(H),21β(H)-hopane with increasing rank, (4) the increases in the homohopane index [22S/(22S + 22R)] and the 17α(H),21β(H)-hopane to 17β(H), 21α(H)-hopane ratio with increasing rank, and (5) the increase of benzo[e]pyrene/(benzo[e]pyrene + benzo[a]pyrene) with increasing rank. In addition, the diagnostic ratios among PAHs and between PAHs and the corresponding hydroxy-PAHs, such as benz[a]anthracene/(benz[a]anthracene + chrysene), indeno[1,2,3-cd]pyrene/(indeno[1,2,3-cd]pyrene + benzo[ghi]perylene), pyrene/OH-pyrene, and chrysene/OH-chrysene can be used to distinguish bituminous from anthracite coal smoke emissions.

Total suspended particles (TSP), collected during June 2002 to July 2003 in Guangzhou, a typical economically developed city in South China, were analyzed for the organic compound compositions using gas chromatography–mass spectrometry (GC/MS). Over 140 organic compounds were detected in the aerosols and grouped into different classes including n-alkanes, hopanoids, polycyclic aromatic hydrocarbons, alkanols, fatty acids, dicarboxylic acids excluding oxalic acid, polyols/polyacids, lignin products, phytosterols, phthalates and water-soluble sugars. The total amounts of the identified organic compounds including unresolved complex mixture (UCM) ranged from 3112 ng/m3 in spring to 5116 ng/m3 in winter, comprising on seasonal average 2.8% of TSP. Primary organic compounds peaked in winter although there are no heating systems burning fuels in Guangzhou. The highest saccharide levels occurred in fall due to agricultural activities. This study demonstrated that utilization of fossil fuels, biomass burning, soil resuspension and plastic/refuse burning are the major contributors to the identified organic compounds in the urban atmosphere of South China.

This study focuses on the chemical characteristics of size-segregated aerosols and the size distribution of submicron aerosol in an urban area of Pearl River Delta (PRD) region, China during 23th October 2010 and 10th January 2011. Light dry haze, with mean PM3 concentration at 130.2 ± 25.4 μg m−3, approximately 1.6 times that for clear days, was frequently observed throughout this period. A particle mass build-up period from 27th October to 06th November 2010 was obtained corresponding to the enhanced light extinction. The results show that organic matter (OM), SO42-, NO3- and NH4+ increased remarkably on the hazy days, and the major enhancement of these species was found in the size range of 0.49–1.5 μm. Higher fraction of SO42- and NO3- in the size range of 0.95–1.5 μm on hazy days increased the water uptake and also the mass concentration. The yield of secondary organics in the size range <0.49 μm showed strong dependent on the aerosol acidity on the hazy days. Light extinction coefficients of different chemical components were also estimated by IMPROVE protocol. Sulfate and OM played an important role in visibility impairment, followed by nitrate (being more important on hazy days) and elemental carbon (EC). The results would help us to better understand the physical and chemical properties of atmospheric aerosols and their influence on the formation of haze in the PRD region.

•Size and mixing state of individual ambient aerosols were measured by a SPAMS.•Carbonaceous and inorganic types showed different mixing state with sulfate/nitrate.•Air mass played a considerable role on the temporal profiles of particle types.•Carbonaceous rather than inorganic types showed distinct diurnal variation.•Two EC particle types LC-EC and NaK-EC may have different origins.Continuous ambient measurement of atmospheric aerosols was performed with a single particle aerosol mass spectrometer (SPAMS) in Guangzhou during summer of 2012. The aerosols mainly consisted of carbonaceous particles as major compositions in submicrometer range, including K-rich (29.8%), internally mixed organics and elemental carbon (ECOC, 13.5%), organic carbon-rich (OC, 18.5%), elemental carbon (EC, 12.3%) and high molecular OC (HMOC, 3.2%), and inorganic types (e.g., Na-rich Na-K, Fe-rich, V-rich, and Cu-rich) as major ones in supermicrometer range. Results show that carbonaceous particles were commonly internally mixed with sulfate and nitrate through atmospheric processing, in particular, with sulfate; inorganic types were dominantly internally mixed with nitrate rather than sulfate, indicative of different evolution processes for carbonaceous and inorganic particles in the atmosphere. It was observed that variations of these particle types were significantly influenced by air mass back trajectories (BTs). Under the influence of continental BTs, carbonaceous types were prevalent, while Na-K and Na-rich types considerably increased when the BTs originated from south marine regions. Number fraction of carbonaceous types exhibited obvious diurnal variation throughout the sampling period, which reflects their relatively stable emission and atmospheric processes. Two EC particle types LC-EC and NaK-EC showed different diurnal distributions, suggesting their different origins. The obtained information on the mixing state and the temporal variation of particle types is essential for developing an understanding on the origin and evolution processes of atmospheric aerosols.

Heavy metals and persistent organic pollutants polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) were analyzed in 34 surface soil samples collected from farmland and 7 soil or dust samples collected from the workshops in South China, where e-waste was dismantled using primitive techniques. The results show that Cd, Cu and Hg were the most abundant metals, in particular Cd pollution was serious in farmland soils, and the median concentrations in farmland soils were beyond the environmental quality standard for soils (China Grade II). A correlation between Cd, Cu, Zn, Pb and PCBs or PBDEs was significant indicating similar sources. Among the PCB congeners, high relative similarity was observed between the e-waste dump site soil (EW1) and Aroclor 1254, implying that the technical product Aroclor 1254 was one of the major sources of PCB contamination. High concentrations of PCBs in workshop dusts (D2 and D3) (1958 and 1675 μg kg−1) demonstrated that the workshops dismantling electrical wires and cables, electrical motors, compressors and aluminum apparatus containing PCBs in lubricants represent strong PCB emission sources to this area. Principal component analysis (PCA) and PBDE homologue patterns verify that farmland soils surrounding the e-waste recycling sites were enriched with lower brominated congeners, and the major source of PBDEs in dust samples might potentially be associated with the extensive use of deca-mix technical products as a flame retardant. The difference between e-waste soils, dusts and farmland soils can be observed in the PCA score plot of PCBs and PBDEs, and E-waste soils and dusts exhibited more diversity than farmland soils. Furthermore, a prediction of the particular kinds of pollution from different recycling activities through the analysis of each contamination and the connections between them was investigated.

Daytime and nighttime PM2.5 samples were collected between August 5 and 16, 2009 and between January 24 and February 4, 2010 in an industrial complex site (site A) and an electronic waste recycling site (site B) to determine the seasonal and diurnal variations of 19 individual polycyclic aromatic hydrocarbons (PAHs) with molecular weight 302 (MW302) including four highly carcinogenic dibenzopyrene (DBP) isomers dibenzo[a,l]pyrene (DBalP), dibenzo[a,e]pyrene (DBaeP), dibenzo[a,i]pyrene (DBaiP), and dibenzo[a,h]pyrene (DBahP). This is the first report on DBP isomers in air particles from South China. The total concentration of PAH MW302 isomers ranged from 1.65 to 3.60 ng m−3 in summer and 3.82 to 9.81 ng m−3 in winter. The strongest peaks in the chromatograms of the MW302 isomers were naphtha[2,1-a]pyrene (N21aP), dibenzo[j,l]fluoranthene (DBjlF), naphtha[1,2-b]fluoranthene (N12bF), naphtha[1,2-k]fluoranthene (N12kF) and dibenzo[a,e]fluoranthene (DBaeF), constituting 52.0 to 55.4% of the total MW302 isomers. All the MW302 isomers showed notable seasonal variations. Most of the MW302 isomers in site B showed distinctive diurnal variations with higher concentrations occurring in the night. Taking into account both concentration and potency equivalence factors (PEFs), the strongest carcinogen in the analyzed samples was DBaiP, and the ratios of sum carcinogenic potency of four highly carcinogenic DBP isomers to benzo[a]pyrene (BaP) was about 0.94 in winter to 1.89 in summer, indicating the importance of DBP isomers for the risk assessment. Health risk assessment indicated that on average, 1 in 100000 residents in the two industrial sites may have an increased risk of cancer due to PAH exposure.