青岛近海PCDD/Fs的沉积通量、毒性当量及来源

用高分辨率气相色谱-质谱方法对青岛胶州湾内外表层沉积物、柱状岩心及贻贝样品中的17种毒性多氯代二苯并二 /呋喃(PCDD/Fs)进行了分析和讨论.表层沉积物的SP_4-8CDD/Fs含量范围在11.6～369pg/g dw,主要以P_4-8CDFs为主.S2,3,7,8-PCDD/Fs含量范围4.1～232.4pg/g dw.在环流作用下沉积物中形成了明显的东-西分布格局.除河口处外,PCDD/F同系物分布基本上相同,即低氯代PCDD/Fs占主导.SP_4-8CDD/Fs沉积通量从1951年起逐渐增大,STEQ沉积通量从1980年显著增大.青岛近海PCDD/Fs的来源相对恒定,推测为城市污水污泥和大气沉降.贝肉中S2,3,7,8-PCDD/Fs为2.9～5.1pg/g dw. TEQ的主要来源为2,3,4,7,8-PeCDF(35%)、2,3,7,8-TCDF(30%)、2,3,7,8,-TCDD(30%).     

垃圾焚烧飞灰或炉渣中二噁的分布特征

分别采集了3种生活垃圾焚烧炉产生的飞灰或熔融炉渣样品,分析了其中的二口恶口英含量及其毒性当量,并讨论了17种2,3,7,8位氯取代的二口恶口英分布特征及其对总毒性当量的贡献.结果表明,机械炉排焚烧炉产生的飞灰中二口恶口英最多,总浓度为319ng/g,毒性当量为6.7ngI-TEQ/g;其次为流化床焚烧炉,产生的飞灰中二口恶口英总浓度为38.7ng/g,毒性当量为0.8ngI-TEQ/g;气化熔融焚烧炉产生的熔融炉渣中二口恶口英很少,总浓度为38.7pg/g,毒性当量仅为1.1pgI-TEQ/g;所有的2,3,7,8位氯取代的13C同位素标记内标化合物回收率在39%~156%之间.尽管不同的垃圾焚烧炉在二口恶口英的生成量上有明显的差别,但是产生的二口恶口英同类物的归一化浓度以及对毒性当量贡献的归一化结果分布特征十分相似,表明3种垃圾焚烧炉在垃圾焚烧过程产生二口恶口英可能具有相似的反应机理.     

Effects of dioxins and polychlorinated biphenyls (PCBs) on thyroid function in infants born in Japan – the second report from research on environmental health

Dioxins (PCDD + PCDF) and polychlorinated biphenyl (PCB) are potentially hazardous compounds and have structural similarity to thyroid hormones. Our research group on “Dioxins and PCB in Human Milk” was organized in 1997 and has been active for the past three years. We collected breast milk from 80 mothers living in Tokyo, Saitama, Ishikawa and Osaka Prefecture in Japan at 5, 30, 150, 300 postpartum days and measured PCDDs, PCDFs and PCBs during 1998–1999. We added another 20 prefectures and cities during 1999–2000. Breast milk was obtained from 415 mothers at 30 postpartum days (breast-feeding group). Blood was taken from infants who were breast-fed at the age of 1 year for evaluation of thyroid and immune functions. Blood was also taken from 53 infants who were bottle-fed (bottle-feeding group) as a control. Serum T4, T3, FT4 and TSH levels in the breast-feeding (n=337) and bottle-feeding (n=53) groups were within normal ranges and were not significantly different between the two groups. Although there were a large geographic differences of dioxins and co-PCB content in breast milk, there were no differences in serum T4, T3, FT4, TSH levels and no significant correlation between the mean serum levels of TSH and TEQ in breast milk. There was a significant correlation between serum TSH at 1 year of age and that from blood on dried filter paper TSH at 5 days of age. We concluded that dioxin intake from breast milk in Japanese infants did not impair thyroid function. However, long-term effects remain to be evaluated.     

多氯联苯污染土壤热脱附研究综述

综述了近年来国内外热脱附技术在修复多氯联苯(polychlorinated biphenyls,PCBs)污染土壤方面的研究进展。温度和停留时间是影响其脱附效率的最主要因素,另外脱附效果还受土壤性质以及载气、压力等其他因素的影响。氧气存在的条件下,脱附过程中会有呋喃(polychlorinated dibenzofurans,PCDFs)生成,导致整体毒性当量增加。PCBs的物理蒸发是其主要的脱附机制,同时伴随着脱氯和降解。协同热脱附通过添加改性剂,有效促进了PCBs的去除以及降解。冷凝,除尘,吸附一系列尾气处理用来降低尾气中PCBs的含量。文章最后给出了当前国内外的应用情况以及存在问题和今后的发展方向。     

青岛及崇明岛食用鱼和鸭中共平面多氯联苯与多氯萘的研究

利用HRGC-HRMS测定了青岛海鱼和上海崇明岛淡水鱼、鸭样品中共平面多氯联苯(co-PCBs)和多氯萘(PCNs)(均以脂肪计)的质量分数,并根据每日摄取量可能带来的健康风险进行了初步探讨. 青岛海鱼中w(co-PCBs)和w(PCNs)平均值约为4 041和225 pg/g,崇明岛淡水鱼约为3 318和640 pg/g. 崇明岛鸭肉中w(co-PCBs)和w(PCNs)平均值分别约为966和43.8 pg/g. 青岛海鱼中PCNs同系物组成(以5-CNs和3-CNs为主)与崇明岛淡水鱼完全不同. 与国内外其他地区鱼和家禽相比,其污染物含量均较低. 所有样品中co-PCBs的毒性当量浓度(WHO-TEQ)为0.68～11.40 pg/g,PCNs的毒性当量浓度(WHO-TEQ)为0.001～0.210 pg/g. 根据当地人群的饮食习惯,两地人群co-PCBs和PCNs每日摄入量远低于WHO对普通人群规定的每日容许摄入量,因此不会对人群健康产生严重的负面效应.      

贵州红枫湖地区水稻土多氯联苯和有机氯农药的残留

调查了红枫湖周边水稻土的7种多氯联苯（PCBs）和13种有机氯农药（OCPs）的含量分布.结果显示,DDTs及其代谢产物、HCHs的异构体、异狄氏剂、七氯等有机氯农药及PCB 28和PCB 52在所有样品中均被检出.与国内外污染区相比,PCBs含量较低.研究区土壤中污染物的组成结果类似,PCBs以3～5氯取代的同属物为主,农药以DDTs为主.剖面土壤中∑PCBs含量范围为8.9～55.9 ng/g,主要以3～5氯取代的PCBs为主,平均占PCBs总量的89%.∑DDTs含量为 4.7～42.6ng/g,以p,p′-DDE,p,p′-DDT为主.DDT/（DDD+DDE）的比率表明红枫湖地区水稻田中DDTs的降解速率不同,暗示其环境条件的差异.α-HCH/γ-HCH为0.28～0.90,表明红枫湖地区水稻田中HCHs在环境中残留时间很长,经历了光解和生物作用等变化.PCBs对TEQ的贡献较低,为0.06～0.51 pg/g.     

被动式采样器与原位鱼体暴露用于监测水体Ah受体效应的比较研究

采用被动式采样器SPMD结合H4ⅡE鼠肝癌细胞离体EROD测试的方法来评价水体中Ah受体效应物质的污染水平.以多环芳烃(PAHs)为目标化合物,在太湖梅梁湾地区选取了5个站点,同时放置SPMD采样器和笼养鲫鱼进行32 d的现场原位暴露实验,然后对SPMD样品提取液进行化学分析和离体EROD测试,对鱼肌肉样进行化学分析和对肝胰脏样进行活体EROD测试.结果表明,随着暴露时间的延长,SPMD样品提取液诱导EROD酶的能力逐渐增强,经过32 d暴露的SPMD样品的提取液其诱导的EROD酶活相当于TCDD的毒性当量值为3.8～6.2 pg/g,而且根据化学分析结果计算的PAHs相当于TCDD的毒性当量值与离体生物测试结果之间相关性很好(R²=0.88),说明PAHs是引起该地区水体EROD效应的一个重要诱导因子;根据化学分析结果而配制的模拟样品的离体EROD测试结果表明,多环芳烃类物质对梅梁湾地区水体Ah受体效应的贡献约为40%～50%.研究还发现,SPMD提取液离体EROD测试结果与同时暴露的鱼体肝胰脏的活体EROD测定结果之间也存在较好的相关性(R²=0.62).因此认为,SPMD结合离体EROD测试的方法能够很好的用于评价水体中Ah受体效应物质的污染水平,并能够用于揭示特定化合物与相应的生物效应之间的定量关系.     

淮北矿区煤矸石多环芳烃污染特征及毒性评价

利用气相色谱-三重四级杆质谱(GC-MS/MS)对采自刘桥二矿的13件煤矸石样品(7件新鲜煤矸石样品,6件风化煤矸石样品)中16种优先级母体多环芳烃(16PAHs)和烷基多环芳烃(a-PAHs)进行了定性和定量分析.结果表明:煤矸石中不仅含有16PAHs,而且含有对应的a-PAHs,后者含量(均值587.88ng/g,...     

Assessment of the daily intake of 62 polychlorinated biphenyls from dietary exposure in South Korea

The dietary intake of polychlorinated biphenyls (PCBs) was estimated using the sum of 62 PCB congeners (∑₆₂PCBs), including seven indicator PCBs and 12 dioxin-like PCBs, in the South Korea. In this study, 200 individual food samples belonging to 40 different foodstuffs were investigated to estimate the distribution of PCB congeners in five sampling cities. PCB exposure was estimated using Korean dietary habits as established by the National Health and Nutrition Examination Survey (NHANES). The PCB concentrations in rice, the most frequently consumed food in Korea, was relatively low in whole food samples. The mean PCB levels measured in fish were the highest in this study, but each fish is consumed in relatively small amounts by the general population. Therefore, the daily dietary intake should also be considered with regard to human exposure to PCBs, especially with the consumption of contaminated foods. Dioxin-like PCB levels were also calculated using TEF values that were established in 2005. The average levels (pg TEQ/g) were 0.0002 for rice and 0.0098 for fish. The dioxin-like PCBs accounted for a relatively small percentage of the total PCBs, compared to previous studies. According to our research, the health risks associated with exposure to PCBs could be estimated using the tolerable daily intake (TDI) of the general population.     

Concentration of DL-PCBs in fish from market of Parma city (north Italy): estimated human intake

The concentrations of 12 congeners of non-ortho and mono-ortho dioxin-like polychlorinated biphenyls (ΣDL-PCB) were measured in 30 fish samples from Parma markets by GC/MS technique. The samples were randomly purchased, choosing the species commonly found in supermarkets. The concentration of DL-PCBs estimated remained under the fixed Italian limit of 4 pg g⁻¹ ww WHO-TEQ (World Health Organization-Toxic Equivalent) in the major part of the samples, so the situation seems to be not at a level sufficient to pose a risk to human health of the Parma population. The medium daily intake for DL-PCBs for Italian consumers (Parma) was also estimated. This value generally resulted minor than 2 pg g⁻¹ ww WHO-TEQ kg⁻¹ body weight, exceeding only in four cases: eel, smooth hound, starry smooth hound and tuna.