Yeru Huang

Concentration and source identification of polycyclic aromatic hydrocarbons and phthalic acid esters in the surface water of the Yangtze River Delta,China

The pollution from polycyclic aromatic hydrocarbons (PAHs) and phthalic acid esters (PAEs) in the surface water of the rapidly urbanized Yangtze River Delta region was investigated. Fourteen surface water samples were collected in June 2010. Water samples were liquid-liquid extracted using methylene chloride and analyzed by gas chromatography-mass spectrometry. Concentrations of PAHs and PAEs ranged 12.9-638.1 ng/L and 61-28550 ng/L, respectively. Fluoranthene, naphthalene, pyrene, phenanthrene, di-2-ethylhexyl phthalate, and di-n-butyl phthalate were the most abundant compounds in the samples. The water samples were moderately polluted with benzo[a]pyrene according to Chinas environmental quality standard for surface water. The two highest concentrations of PAHs and PAEs occurred in samples from Taihu Lake, Wuxi City and the western section of Yangchenghu Lake. Potential sources of pollution at S7 were petroleum combustion and the plastics industry, and at Yangchenghu Lake were petroleum combustion and domestic waste. Pollution in samples from the Beijing-Hangzhou Grand Canal originated from diesel engines. There were no obvious sources of pollution for the other water samples. These results can be used as reference levels for future monitoring programs of pollution from PAHs and PAEs.

Concentrations and possible sources of polychlorinated biphenyls in the surface water of the Yangtze River Delta, China.

In this study, polychlorinated biphenyls (PCBs) pollution in the surface water of the Yangtze River Delta (YRD) was investigated. A total of 26 samples were collected from water bodies in three cities within the YRD during the dry season from October to November of 2009. The total PCBs (dissolved plus particulate) ranged from 1.23 to 16.6 ng L(-1) and were dominated by tri-, tetra-, and penta-chlorinated biphenyls. The mean PCBs in the Beijing-Hangzhou Grand Canal and the Yangtze River were 8.84 and 3.36 ng L(-1), respectively. A t-test showed that there were no significant differences in the concentration of samples from the metropolitan area and the development zone. According to the Chinese national environmental quality standards for surface water (GB 3838-2002), the concentrations of PCBs observed in this study do not pose a hazard to aquatic or human health. Overall, this study described the PCB concentration and homolog distribution patterns in one of the most rapidly developing areas in China, and the results can be used as reference levels for future PCB monitoring programs.

Passive air sampling of organochlorine pesticides and polychlorinated biphenyls in the Yangtze River Delta, China: Concentrations, distributions, and cancer risk assessment

The Yangtze River Delta (YRD) has been quickly industrialized and urbanized. Passive air sampling of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) was carried out in the YRD in 2010-2011 to investigate their spatiotemporal distributions and estimate the risk of cancer from their inhalation. Annual concentrations were 151, 168, 18.8, 110, 17.9, and 35.0 pg m(-3) for HCB, ∑DDTs, ∑HCHs, ∑chlordane, mirex, and PCBs, respectively. The highest OCP and PCB concentrations were generally detected in the autumn and winter. The average concentrations of OCPs and PCBs for the different site groups followed the order urban ≈ urban-rural transition > rural. The lifetime excess cancer risks from the inhalation of OCPs and PCBs were <1.0 × 10(-6). The predicted cancer cases per lifetime associated with the inhalation of OCPs and PCBs are 12, 7, and 4 per ten thousand people for urban, urban-rural transition, and rural areas, respectively.

Levels, Seasonal Patterns, and Potential Sources of Organochlorine Pesticides in the Urban Atmosphere of Beijing, China

Air samples collected monthly on the roof of a building in Beijing were analyzed for the levels, seasonal patterns, and potential sources of organochlorine pesticides (OCPs). A high-volume air sampler with polyurethane foam and quartz fiber filters was used to collect monthly samples from November 2005 to April 2009. Hexachlorobenzene (HCB) and DDT isomers were the most abundant organochlorinated pesticides in the Beijing atmosphere. Higher OCP concentrations were generally found in summer, except for HCB. Coal combustion, waste incineration, and fuel combustion were assumed to be the potential HCB emission sources. Significant input of either of these OCPs during our study period was considered very unlikely.

Spatial distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Camphor (Cinnamomum camphora) tree bark from Southern Jiangsu, China.

The concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) were investigated in Camphor tree bark from Southern Jiangsu, China. Tree bark samples were collected in August 2012. The Σ15PAHs concentrations were ranged from 6.18 to 1560 ng g(-1)dry weight (dw), with an average value of 407 ng g(-1)dw. Generally, the concentrations of PAHs in the suburban areas were the highest, followed by urban and rural areas. Principal component analysis and diagnostic ratios results showed that vehicle emission, biomass and coal combustion and industrial emission were the major sources of PAHs in tree bark from Southern Jiangsu. Good correlation was found between tree bark and polyurethane foam (PUF) samplers, indicating that both of them respond well to the gas-phase PAHs monitoring.

Concentration and Gas-particle Partitioning of Hexachlorobenzene in the Ambient Air Before and After the Beijing Olympic Games

Systematic studies of hexachlorobenzene in the ambient air before and after the Beijing Olympic Games were carried out during July 2007 to March 2009. Air samples were collected around 20th monthly on the roof of a building near the Olympic center. The average concentration of hexachlorobenzene was 264 pg·m−3, which was higher in winter than other seasons. However, hexachlorobenzene concentration was decreased clearly in winter in 2008 compare with in 2007 due to the implementation of a series of “Green Olympic” policies. Gas-particle partitioning shows that the increase of hexachlorobenzene levels in winter time was mainly contributed by the high total suspended particulate from combustion processes such as coal-burning and traffic emission.

Polycyclic aromatic hydrocarbon concentrations, compositions, sources, and associated carcinogenic risks to humans in farmland soils and riverine sediments from Guiyu, China.

The concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) were measured in 23 farmland soil samples and 10 riverine sediment samples from Guiyu, China, and the carcinogenic risks associated with PAHs in the samples were evaluated. Guiyu is the largest electronic waste (EW) dismantling area globally, and has been well known for the primitive and crude manner in which EWs are disposed, such as by open burning and roasting. The total PAH concentrations were 56-567 ng/g in the soils and 181-3034 ng/g in the sediments. The Shanglian and Huamei districts were found to be more contaminated with PAHs than the north of Guiyu. The soils were relatively weakly contaminated but the sediments were more contaminated, and sediments in some river sections might cause carcinogenic risks to the groundwater system. The PAHs in the soils were derived from combustion sources, but the PAHs in the sediments were derived from both combustion and petroleum sources.

Review on the analytical methods of emerging persistent organic pollutants

Polybrominated diphenyl ethers (PBDEs), polybrominated biphenyls (PBBs), perfluorooctanoic acid (PFOA), perfluorooctyl sulfonates (PFOS), chlordecone and polybrominated dibenzo- p -dioxin and dibenzofurans (PBDD/Fs), as the new listed POPs in Stockholm Convention and emerging POPs, were increasingly concerned by environmental scientists. The research work about the residue’s characteristic, source analysis, trends evolution, transport, bioaccumulation, and toxic effects of these emerging chemicals depended on the development of the analytical methods. Analytical procedures of PBDEs and PBBs were similar to those of organochlorine pesticides (OCPs) and poly chlorinated biphenyls (PCBs), due to their similar physical and chemicalcharacteristics with “Dirty Dozen”. Many extraction methods, such as Soxhlet extraction, automatic Soxhlet extraction, supersonic extraction, microwave assisted extraction, pressurized fluid extraction, were applied for water, sediment, soil and particulate matter. Common clean-up steps were sulfuric acid silica gel cartridge, multiple layer chromatography column and GPC. Although HRGC/HRMS and GC/MS/MS were effective for environmental background samples, GC/MS-EI and GC/MS-NCI were most popular for determinations of the PBDEs and PBBs indicators or markers. HPLC/MS/MS with solid phase extraction was developed for the perfluorinated alkyl acids, sulfonates and their salts. HLB solid phase column was efficient for PFOA/PFOSs recoveries from water samples, as the weak anion exchange column could raise the recoveries of perfluorinated alkyl acids and sulfonates with the carbon chain ranging from 4 to 14. Acetone was necessary in the extraction because of the polarity of clordecone. The GC injector and capillary column needed cleaning carefully when clordecone was analyzed by GC/ECD and GC/MS, otherwise the strong tailing of chromatographic peak would make the exact qualitative and quantitative impossible. The analysis procedures for polybrominateddibenzo-p-dioxin and dibenzofurans (PBDD/Fs) were similar to those of PCDD/Fs. Florisil or active carbon-impregnated silica gel column were packed to separate PBDEs and PBDD/Fs. The instrumental conditions were optimized to prevent from the thermal degradation of higher brominated compounds. The application of the method was also depended on the improvement of PBDD/Fs reference materials.