广州市珠江隧道二噁英类化合物的含量与分布

对广州市珠江隧道中气相和颗粒态样品,以及隧道附近大气样品中的二噁英类化合物(PCDD/Fs)进行了检测.结果表明,珠江隧道中17种2,3,7,8-氯取代二苯对二噁英和二苯并呋喃(包括气相和颗粒态)的浓度范围夏季(7月)为3830.9 fg·m-3-4690.2 fg·m-3,毒性当量为193.0 fg·I-TEQ·m-3-217.0fg·I-TEQ·m-3;冬季(12月)为18600.8 fg·m-3-20388.8 fg·m-3,毒性当量为1275.4fg·I-TEQ·m-3-1392.2 fg·I-TEQ·m-3;冬季浓度远远高于夏季,隧道内冬季浓度是夏季浓度的3-4倍.环境大气样品中PCDD/Fs浓度低于隧道.同时期样品中,隧道出口、隧道中间、隧道外以及沙面公园中PCDD/Fs的浓度呈递减趋势,并且在冬季这种趋势更加明显,冬季隧道内浓度是环境大气浓度的2倍(毒性当量为5倍).加权平均后PCDD/Fs的排放因子值为1994.6 pg·km-1·辆-1(104.8 pg I-TEQ).     

The major components of particles emitted during recycling of waste printed circuit boards in a typical e-waste workshop of South China

Electronic waste from across the world is dismantled and disposed of in China. The low-tech recycling methods have caused severe air pollution. Air particle samples from a typical workshop of South China engaged in recycling waste printed circuit boards have been analyzed with respect to chemical constituents. This is the first report on the chemical composition of particulate matter (PM) emitted in an e-waste recycling workshop of South China. The results show that the composition of PM from this recycling process was totally different from other emission sources. Organic matter comprised 46.7–51.6% of the PM. The major organic constituents were organophosphates consisting mainly of triphenyl phosphate (TPP) and its methyl substituted compounds, methyl esters of hexadecanoic and octadecanoic acids, levoglucosan and bisphenol A. TPP and bisphenol A were present at 1–5 orders of magnitude higher than in other indoor and outdoor environments throughout the world, which implies that they might be used as potential markers for e-waste recycling. The elemental carbon, inorganic elements and ions had a minor contribution to the PM (<5% each). The inorganic elements were dominated by phosphorus and followed by crustal elements and metal elements Pb, Zn, Sn, and lesser Cu, Sb, Mn, Ni, Ba and Cd. The recycling of printed circuit boards was demonstrated as an important contributor of heavy metal contamination, particularly Cd, Pb and Ni, to the local environment. These findings suggest that this recycling method represents a strong source of PM associated with pollutants to the ambient atmosphere of an e-waste recycling locale.     

Characterization of organic compounds and molecular tracers from biomass burning smoke in South China I: Broad-leaf trees and shrubs

Biomass burning smoke constituents are worthy of concern due to its influence on climate and human health. The organic constituents and distributions of molecular tracers emitted from burning smoke of six natural vegetations including monsoon evergreen broad-leaf trees and shrubs in South China were determined in this study. The gas and particle samples were collected and analyzed by gas chromatography–mass spectrometry. The major organic components in these smoke samples are methoxyphenols from lignin and saccharides from cellulose. Polycyclic aromatic hydrocarbons (PAHs) are also present as minor constituents. Furanose, pyranose and their dianhydrides are the first reported in the biomass burning smoke. Some unique biomarkers were detected in this study which may be useful as specific tracers. The corresponding tracer/OC ratios are used as indicators for the two types of biomass burning. U/R (1.06–1.72) in the smoke samples may be used as parameters to distinguish broad-leaf trees and shrubs from fossil fuel. Other useful diagnostic ratios such as methylphenanthrene to phenanthrene (MPhe/Phe), phenanthrene to phenanthrene plus anthracene (Phe/(Phe + Ant)) and fluoranthene to fluoranthene plus pyrene (Flu/(Flu + Pyr)) and octadecenoic acid/OC are also identified in this study. These results are useful in efforts to better understand the emission characterization of biomass burning in South China and the contribution of regional biomass burning to global climate change.     

邻苯二甲酸二丁酯的酶促降解性的研究

测定了Ｐｓｅｕｄｏｍｏｎａｓ ｆｌｕｏｒｅｓｃｅｎｓ ＦＳ１的邻苯二甲酸酯降解酶对邻苯二甲酸二丁酯的降解特性;提出了邻苯二甲酸二丁酯酶促降解的途径,Ｐｓｅｕｄｏｍｏｎａｓ ｆｌｕｏｒｅｓｃｅｎｓ ＦＳ１细胞中的颗粒部分、溶液部分对邻苯二甲酸二丁酯都具有降解作用,Ｐｓｅｕｄｏｍｏｎａｓ ｆｌｕｏｒｅｓｃｅｎｓ ＦＳ１的邻苯二甲酸酯降解酶尾胞内酶;Ｐｓｅｕｄｏｍｏｎａｓ ｆｌｕｏｒｅｓｃｅｎｓ ＦＳ１     

Polychlorinated biphenyls contamination in urban soil of Shanghai: level, compositional profiles and source identification

Surface soil samples taken from 55 sampling sites at the urban areas of Shanghai were collected and analyzed for the occurrence of 144 polychlorinated biphenyls (PCBs) by GC-μECD. The results showed that totally 74 PCB congeners were identified and the mean concentration of total PCBs was 3057 ng kg⁻¹ with a range of 232 to 11325 ng kg⁻¹. Compared with the related reports, the level of PCBs contamination in this study was approximately equal to the global background value in soils, but higher than Chinese background for rural and urban soils. According to the compositional profiles of PCBs homologues, a higher proportion of low chlorinated (from tri-CBs to hexa-CBs) was observed. The results indicated that PCB15 + 13, PCB18, PCB28, PCB104 + 47 and PCB153 were the most dominant congeners among the identified PCBs. Through homologues analysis, cluster analysis and principal component analysis (PCA), it was found that PCBs were stretched from mixed local sources, and appeared to be mostly originated by Aroclor 1260- and 1254-like mixtures as well as some samples influenced by Aroclor 1232 and 1242. The correlation analysis showed the relatively good correlation among the PCB homologues and soil total organic carbon (TOC), suggesting important influence of soil TOC on PCBs contamination in soil matrix in Shanghai region. The toxic equivalency (TEQ) concentrations of these six dioxin-like PCBs detected in urban soil samples range from 2.71 to 24.9 pg kg⁻¹-PCDDeq with a mean 8.18 pg kg⁻¹-PCDDeq.     

Seasonal and spatial changes of free and bound organic acids in total suspended particles in Guangzhou,China

The concentrations and compositions of free and bound organic acids in total suspended particles from typical urban, suburban and forest park sites of Guangzhou were determined in this study. The free form of organic acids (solvent extractable) in aerosols in Guangzhou varied with site and season. The suburban samples contained the highest contents of alkanoic, alkenoic and dicarboxylic acids. These findings were consistent with a higher supply of hydrocarbons and NOx in the suburban area. However, concentrations of aromatic acids were similar in the urban, suburban and forest park sites. Generally, winter season samples of the acids from anthropogenic sources contained more organic acids than summer season samples due to stronger removal by wet deposition in the summer. For the acids from botanic sources, the summer season samples were higher. In addition to the free acids, bound acids (solvent non-extractable) mainly formed by esterification of free acids were also found in the samples. In general, bound acids were higher than free acids. Esterification is mainly controlled by the pKa of organic acids and the atmospheric pH value. This explains why aromatic and dicarboxylic acids occur mainly as bound forms and why the samples from urban sites contained high levels of bound acids as the pH of rain water can reach 4.53.Concentrations of alkanoic and alkenoic acids in the aerosols of Guangzhou were much higher than those in the other areas studied.     

Preliminary study on the occurrence and distribution of polycyclic musks in a wastewater treatment plant in Guandong, China

The occurrence and distributions of six polycyclic musks were studied in influent, primary and effluent waters from a municipal wastewater treatment plant (WWTP) in Guangdong. Five polycyclic musk compounds, 1,2,3,5,6,7-hexahydro-1,1,2,3,3-pentamethyl-4H-inden-4-one (DPMI), 4-acetyl-1,1-dimethyl-6-tert-butylindan (ADBI), 6-acetyl-1,1,2,3,3,5-hexamethylindan (AHMI), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta(g)-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronaphthalene (AHTN) were found in wastewater in the WWTP. DPMI, HHCB and AHTN were measured at 0.38-0.69, 11.5-146, 0.89-3.47 microg/l, respectively, in influents. Meanwhile 0.06-0.10 microg/l DPMI, 0.95-2.05 microg/l HHCB, 0.10-0.14 microg/l AHTN were detected in effluents, ADBI and AHMI were also detected in some primary waters and effluents. The results suggested that wastewater from cosmetic plants cause high loadings of polycyclic musks to this WWTP. Under the currently applied treatment technology, the removal efficiencies achieved were 61-75% for DPMI, 86-97% for HHCB and 87-96% for AHTN by transfer to sludge as the main removal route.     

污灌区重金属污染对土壤的危害

由于土壤中重金属元素的含量对人体健康影响很大,淮阴市环境监测中心站于１９９３年至１９９７年造反某污灌区中０．６６７ｈｍ＾２的蔬菜田及其邻近的某一地下水灌区中０．６６７ｈｍ＾２的蔬菜田按梅花布点法分别布设８个测点,对其土壤中的总镉、总汞、总砷、总铬和总锅进行监测。结果表明,地下水藻区５年来综合污染指数变化不大,污染等级属安全级,说明该灌区没有受到重金属污染,而污灌区的综合污染指数逐年增高,１９９５年     

含锑工业废水的样品保存方法研究

选取5-Br-PADAP光度法和原子吸收法分析预处理后水样的保存效果,经检测发现利用HNO,-HC1溶液作为固定剂,调节pH〈1后在无色玻璃瓶中贮存的样品,常温下可保存31d,锑回收率达95％以上,同时前处理带入的干扰离子最少,能够满足验收废水监测中质量控制要求。