广州天河区大气中二噁(口英)年度监测及气固分配规律

对广州天河区大气中二噁(口英)进行年度监测和气固分配模式的研究。结果表明,天河区大气中存在较高浓度的二噁(口英);低氯代二噁(口英)对毒性当量贡献较大,其主要分布在气相,2,3,4,7,8-PeCDF对毒性当量贡献最大,其贡献超过35%;高氯代二噁(口英)(主要是OCDF、OCDD、1,2,3,4,6,7,8-HpCDF和1,2,3,4,6,7,8-HpCDD)对浓度贡献较大,其主要分布在颗粒相。     

济南市大气细颗粒物中二(口恶)英污染水平及季节变化

2021年对济南市大气PM_2.5中17种2,3,7,8氯取代二(口恶)英(PCDD/Fs)污染现状进行监测。对其异构体分布、指示性单体、季节变化规律等特征及其与常规污染物相关性进行了分析。结果表明:大气PM_2.5中PCDD/Fs浓度范围和年平均值分别为0.157~1.595 pg/m³和0.785 pg/m³,而毒性当量(以I-TEQ计)范围和年平均值分别为0.009~0.116 pg TEQ/m³和0.052 pg TEQ/m³。PCDD/Fs浓度与毒性当量季节变化特征显著,均呈现出冬季>春季>秋季>夏季的情况,可能由季节性排放源和气象条件不同导致。不同季节PCDD/Fs异构体分布模式一致,主要由高氯代(1,2,3,4,6,7,8-HpCDF、OCDD、OCDF和1,2,3,4,6,7,8-HpCDD)单体组成;而对毒性当量贡献最大的单体是2,3,4,7,8-PeCDF,其与总毒性当量具有较好的相关性。同时,PCDD/Fs浓度与SO₂、NO₂、PM_2.5等大气常规污染物呈显著正相关。这表明,大气PM_2.5中PCDD/Fs与常规污染物的生成和排放密切相关。     

杭州城区环境空气中二噁英浓度状况研究

依据2009年7月至2012年2月连续3年对杭州城区环境空气中二噁英(PCDD/Fs)采样分析结果得知,杭州城区环境空气中二噁英毒性当量质量浓度变化范围为0.13~0.55 pg TEQ/m~3,均值为0.34 pg TEQ/m~3。城区环境空气中二噁英浓度季节变化不显著,夏季略低于冬季;城区范围内不同功能区之间二噁英浓度差别不显著;连续3年监测结果未显现二噁英年度变化趋势。沙尘暴天气环境空气中二噁英浓度显著增高,日常天气和烟花爆竹集中燃放天气环境空气中二噁英形态分布存在明显区别,烟花爆竹集中燃放期间八氯代二苯并-对-二噁英(OCDD)占总质量浓度比例显著提高。利用IBM SPSS Statistics 19.0统计软件对24个监测结果聚类分析发现,杭州城区环境空气中二噁英的同类物分布具有明显的"源"分布特征。     

某典型生活垃圾焚烧企业烟气中二噁英类变化特征

本文选取了1家典型的生活垃圾焚烧企业作为研究对象,分别采集了净化前和净化后的烟气,结果表明:净化后的烟气中二噁英毒性当量浓度均低于0.1 ng TEQ/Nm 3,去除效率为98.3%;净化前二噁英主要以“从头合成”为主,净化后变化成“前驱物合成”为主;无论是烟气净化前还是净化后,O 8CDD、1,2,3,4,6,7,8-H 7CDD和1,2,3,4,6,7,8-H 7CDF,占比都是最大的;通过相关性分析,1,2,3,4,7,8-H 6CDF质量浓度与I-TEQ相关性最高,可作为二噁英潜在的测定指示物。通过对比研究净化前后的烟气,初步掌握了二噁英工艺流程中变化特征,为企业焚烧控制技术和环境管理提供了数据支持。     

染料中二噁英类化合物的分析方法研究进展

综述了染料中二噁英类化合物的研究进展,指出染料基质复杂,化学结构差异较大,其中二噁英的预处理和检测需根据染料的性质选择最佳的方法;染料中二噁英含量较高,对环境和人体健康影响较大,而原料中的氯醌类物质是其主要污染源。     

M12半自动净化法与手工净化法应用于飞灰中二噁英类检测比较

研究比较了M12半自动净化法与手工净化法应用于二噁英检测的效果。结果显示,采用高分辨气相色谱-高分辨质谱法(HRGC-HRMS)检测飞灰样品中的二噁英,手工净化法的回收率要优于M12半自动净化法的回收率,但M12半自动净化法除2种单体外,其余单体回收率均满足对二噁英的分析要求,且2种净化方法所得二噁英的总毒性当量结果相近,证明手工净化法与HRGC-HRMS联用检测飞灰中二噁英的效果较好,但M12半自动净化法也能够满足HRGC-HRMS检测二噁英的净化要求。应用酶联免疫法检测飞灰样品中二噁英的总毒性量,当样品中二噁英浓度较高时,M12半自动净化法和手工净化法净化测得结果与基准值一致性较好;当样品中二噁英浓度较低时,手工净化法检测结果与基准值差别较大,表明酶联免疫法更适合用M12半自动净化法进行净化。     

鞍山市城区采暖期大气PM_(2.5)中PAHs的污染特征研究

通过对鞍山市(1个工业区、2个工业区周边、3个居住区、1个对照点)2015年1月采暖期大气PM_(2.5)中多环芳烃(PAHs)的监测,采用BaP当量致毒系数TEF,分析了鞍山市大气PM_(2.5)中典型PAHs毒性当量分布特征。研究表明,鞍山市大气PM2.5中工业区及工业区周边Ba P毒性当量浓度要远高于居住区和对照点,污染物主要由4~6环的PAHs组成,很强致癌BaP当量浓度为9.351~38.59 ng/m3。     

深圳市大气中PCDD/Fs污染水平初步研究

目的:了解深圳市大气中二噁(PCDD/Fs)的污染水平和分布特征。方法:利用大流量空气采样器分别采集6个采样点的空气样品,每个采样点采集两个平行样品。参照美国环保总局(US EPA Method TO-9A)二噁的检测方法,通过高分辨气相色谱-高分辨双聚焦磁式质谱仪(HRGC/HRMS)对大气样品中17种具有毒性当量因子(TEF)的单体进行了定性和定量分析。结果:∑PCDD/Fs的浓度范围为0.23～11.88pg/m3(平均值为3.84 pg/m3)。毒性当量浓度范围为0.014～0.29 pg I-TEQ/m3(平均值为0.135 pg I-TEQ/m3)。OCDD、HpCDD、HpCDF、OCDF、HxCDF是丰度较大的单体,分别占总浓度的48.21%、15.85%、11.37%、7.40%、6.59%。PCDDs和PCDFs单体浓度(除OCDF之外)均随氯原子取代个数的增加而增大。2,3,4,7,8-PeCDF对总的毒性当量贡献最大,占总毒性当量浓度的38.87%。六个采样点中有三个地点二噁同系物分布显示了"源"的特征,而另外三个地点则显示了"汇"的特征。成人的PCDD/Fs暴露量为0.0023～0.047 pg I-TEQ/kg.day;儿童PCDD/Fs暴露量为0.0052～0.11 pg I-TEQ/kg.day。结论:深圳市大气样品中二噁浓度低于国内一些城市研究水平,而高于日本、欧美国家的研究水平。     

乌鲁木齐南部冬季空气中气相多环芳烃的特征

本研究选择乌鲁木齐南部大气作为研究对象,利用TSP串PUF大流量采样器从2011年12月至2012年2月采集气相多环芳烃,并对气相中多环芳烃的含量和分布特征进行了分析。结果表明,大气气相多环芳烃中二环和三环的质量分别占总量的56%和43%;通过特征分子含量比值法对大气气相中多环芳烃的来源进行研究,结果表明,乌鲁木齐南部冬季大气气相中的多环芳烃主要来自于化石燃料和生物质的燃烧;毒性当量因子法分析表明,大气气相中90%样品的多环芳烃总毒性当量(Ba Peq)浓度均低于世界卫生组织建议的限值(1 ng/m3)。     

氯苯类化合物在大气中分布特征探究

建立环境空气和有组织废气排放模拟污染源,以玻璃纤维滤膜+玻璃棉和活性炭为吸附材料采集大气中氯苯类化合物,使用气相色谱法测定各组分,考察氯苯类化合物在大气气相和颗粒物中的分布特征。结果显示,环境空气和固定污染源有组织排放废气中一氯代至四氯代苯类各组分主要分布在大气气相中,颗粒物中少有分布,说明现行环境监测方法以固体吸附剂采集测定大气中的氯苯类化合物可行。     

上海市危险废物焚烧行业二噁英排放特征研究

通过对上海市危险废物焚烧行业焚烧炉排放烟气数据的分析，结果表明：不管是医疗废物焚烧炉还是一般危险废物焚烧炉，其二蟋英分布规律大致相同；PCDFs对二曝英的贡献率远高于PCDDs；实测检出的二嚼英异构体中，占二嚼英总量比例较大的依次为1，2，3，4，6，7，8-HpCDF、1，2，3，4，6，7，8-HpCDD和OCDD；I—TEQ贡献最高的二嚼英异构体为2，3，4，7，8-PeCDF，贡献率达31．08％～53．56％。17种二喏英异构体与I—TEQ的相关性分析表明，仅2，3，4，7，8-PeCDF在2类焚烧炉中与I—TEQ均存在相关性，其相关系数分别为0．989和0．998，可以作为潜在的测定指示物。     

杭州城区环境空气中二口恶英浓度状况研究

依据2009年7月至2012年2月连续3年对杭州城区环境空气中二英（PCDD/Fs）采样分析结果得知，杭州城区环境空气中二英毒性当量质量浓度变化范围为0.13～0.55 pg TEQ/m³，均值为0.34 pg TEQ/m³。城区环境空气中二英浓度季节变化不显著，夏季略低于冬季；城区范围内不同功能区之间二英浓度差别不显著；连续3年监测结果未显现二英年度变化趋势。沙尘暴天气环境空气中二英浓度显著增高，日常天气和烟花爆竹集中燃放天气环境空气中二英形态分布存在明显区别，烟花爆竹集中燃放期间八氯代二苯并-对-二英（OCDD）占总质量浓度比例显著提高。利用IBM SPSS Statistics 19.0统计软件对24个监测结果聚类分析发现，杭州城区环境空气中二英的同类物分布具有明显的“源”分布特征。     

Large variation in breast milk levels of organohalogenated compounds is dependent on mother's age, changes in body composition and exposures early in life

We identified factors that are important determinants of body burdens (breast milk levels) of polychlorinated biphenyls (PCBs), dioxins (polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs)) and polybrominated diphenyl ethers (PBDEs). PCBs, PCDD/Fs and PBDEs were analysed in breast milk from up to 325 first-time mothers in Uppsala, Sweden, who delivered between 1996 and 2006. Hierarchical clustering was used as a method for identification of groups of compounds with common sources of exposure and similar toxicokinetics. Based on correlations between levels of single compounds/congeners in breast milk, distinctly separated clusters were formed, strongly dependent on structural similarities of the organohalogen molecules. In a multiple regression model, levels of PCBs (except PCB 28), PCDD/Fs and BDE-153 were positively associated with age of the mother and weight loss after delivery and inversely associated with pre-pregnancy BMI (body mass index) and weight gain during pregnancy. Higher levels of mono-ortho PCB TEQ, non-ortho PCB TEQ and BDE-153 in milk were found among women with high physical activity. Women who were breastfed during infancy and grew up on the Baltic coast of Sweden, with high availability of contaminated fish from the Baltic sea, had higher levels of PCBs and PCDD/Fs in breast milk indicating that exposure early in life from breast milk and contaminated fish may still affect body burdens at the time of pregnancy. The importance of current consumption of fatty Baltic fish as a source of exposure was supported by the positive association with breast milk levels of mono-ortho PCB TEQ, PCDF TEQ and BDE-153. The results show that, in contrast to the lower brominated PBDE congeners, the hexa-brominated BDE-153 resembles the chlorinated compounds with regards to determinants in breast milk. This suggests that some of the PBDEs may have toxicokinetic properties and that are similar to the PCBs and PCDD/Fs. Our results show that a few simple advices to women regarding weight changes in connection with pregnancy and consumption of contaminated fatty fish during the whole lifetime may lower the levels of dioxins in breast milk by up to 60%.     

The variability of PCDD/F concentrations in the effluent of wastewater treatment plants with regard to their hydrological environment

The occurrence, concentrations, patterns, and loads of 17 2,3,7,8-substituted congeners of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in treated wastewater collected at the outlets from 14 wastewater treatment plants (WTPs), divided into three size categories. The analysis also considered the effect of wastewater outflow on the final concentrations of PCDDs/Fs, as the samples were collected during flooding and stable hydrological conditions. None of the studied WTPs were found to completely remove toxic congeners of PCDDs/Fs from wastewater: the PCDD concentrations in the outgoing effluent during stable wastewater flow ranged from 2.99 to 177.19 pg/L, PCDFs from 6.05 to 51.30 pg/L, and the Toxic Equivalent (TEQ) was between 0.94 and 4.87 pg/L. The results from high wastewater flow were less diversified, ranging from 5.04 to 8.85 pg/L for PCDDs, from 11.47 to 32.33 pg/L for PCDFs and from 2.00 to 4.65 pg/L for TEQ. The smallest WTPs demonstrated the highest average total and TEQ concentrations due to limited volume, short retention time and outdated technology, and, hence, insufficient treatment efficiency. The largest WTPs have the potential to substantially affect the quality of river water, as despite being associated with the lowest concentrations, they released much greater volumes of treated wastewater and, hence, the greatest amounts of analyzed compounds. Elevated TEQ values were observed at high flow in all WTP size categories indicating the impact of high and stable wastewater flow on the concentrations of the observed PCDDs/Fs.     

Chlorinated and brominated dibenzo-p-dioxins and dibenzofurans in surface sediment from Taihu Lake, China

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in surface sediment samples from Taihu Lake--an important water supply of the Yangtze River Delta, China--were investigated in the present study. Concentrations of PCDD/Fs ranged from 0.91 to 4.8 pg TEQ g(-1) dw (mean: 2.9 pg TEQ g(-1) dw, TEQ: Toxic Equivalent), which were all higher than the threshold effect level established by interim sediment quality guidelines in Canada (0.85 pg TEQ g(-1) dw). The levels of PBDD/Fs ranged from 0.16 to 1.6 pg TEQ g(-1) dw (mean: 0.52 pg TEQ g(-1) dw) and accounted for 5-33% (mean: 14%) of the total PCDD/Fs and PBDD/Fs TEQ. Comparatively, the abundance of sedimentary PCDD/Fs in the three regions (Meiliang Bay, Gonghu Bay, and Xukou Bay) showed a decreasing trend from the inflow region to the outflow region, while no significant difference was observed among their 2,3,7,8-PBDD/Fs levels, which suggested that the sources of PCDD/Fs and PBDD/Fs differed in this area. Principal component analysis suggested that the historical production/usage of pentachlorophenol and sodium pentachlorophenate was the dominant source of PCDD/Fs in the sediment of these regions. Although the specific sources of PBDD/Fs in the sediment of Taihu Lake were unclear, it was suspected to be due to atmospheric deposition; however, an additional study is needed to confirm this.     

Concentrations and accumulation profiles of PCDDs, PCDFs and dioxin-like PCBs in adipose fat tissues of Korean women

Reports on residue levels and accumulation profiles of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in human adipose tissue are scarce in Korea. In this study, concentrations and accumulation features of PCDD/Fs and DL-PCBs were determined in the samples of adipose tissue collected from Korean women in 2007-2008. The total dioxin-like toxic equivalent (TEQ) concentrations (3.4-42 pg g(-1) lipid wt) in Korean adipose tissues were similar to those reported in European and other Asian countries. The relative contributions of individual compounds to total TEQs were as follows: non-ortho PCBs (mean: 45%) > PCDFs (28%) > PCDDs (24%) > mono-ortho PCBs (3%), a pattern similar to those reported for seafoods in Korea. The dominant PCDD/F congeners found in adipose tissues were OCDD and 2,3,4,7,8-PeCDF and dominant PCBs were 118, 156 and 105. No correlation was found between subject's age and concentrations of dioxin-like contaminants. Body mass index was not correlated with concentrations of PCDD/Fs and was negatively (p < 0.001) correlated with concentrations of DL-PCBs. The results of this study provide baseline information on PCDD/Fs and DL-PCBs in adipose tissues of the general population in Korea.     

Distribution patterns of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans in sediments of the Xiangjiang River, China

We investigated the occurrence and distribution patterns of 2,3,7,8-substituted polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in six sediment samples from the Xiangjiang River, Hunan Province, People’s Republic of China. Total concentrations of PCDD/Fs ranged from 876 to 497,759 (mean 160,766) ng/kg dw, the highest of which exceeded that have ever been reported for sediment samples. World Health Organization total toxicity equivalent (WHO-TEQ) concentrations in three out of six samples were significantly higher than the guidance level (21.5?ng WHO-TEQ/kg dw) suggested by Canadian Sediment Quality Guideline. A predominance of octachlorodibenzo-p-dioxin (OCDD) was observed with an average contribution of 90.8% to the total PCDD/F concentrations, while 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin (HpCDD) was the major contributor to the PCDD/F WHO-TEQ concentrations in most of the sites. Such high levels of OCDD and HpCDD may be attributed to the presence of PCP/PCP-Na pollution, although MB-WW, agricultural straw open burning, and boilers–hazardous wastes were also the potential sources of PCDD/Fs. This is the first report for the concentrations and congener profiles of PCDD/Fs in sediment samples from the Xiangtan, Zhuzhou, and Changsha sections of the Xiangjiang River, providing scientific evidence for establishing priorities to reduce ecological risks posed by PCDD/Fs in the rapidly developing areas of Hunan Province and elsewhere.     

广州大气颗粒物中二噁含量的初步研究

2004年夏季在广州四个不同区域采集大气颗粒物样品,参照美国环保局(US EPA)标准方法测定其中二噁的含量,采用热分解光学分析法测定元素碳和有机碳的含量。结果表明,花都、荔湾、天河、黄埔大气颗粒物中二噁浓度(毒性当量)平均值分别为3815fg/m3(104.6fg I-TEQ/m3)、12777fg/m3(430.5fg I-TEQ/m3)、6963fg/m3(163.7fg I-TEQ/m3)、10953fg/m3(769.3fg I-TEQ/m3)。简单地分析了广州大气颗粒物中二噁的含量特征,以及与元素碳、有机碳之间的相关性。