Temporal and life history related trends of perfluorochemicals in harbor porpoises from the Danish North Sea     

Galatius A  Dietz R  Rigét FF  Sonne C  Kinze CC  Lockyer C  Bossi R 《Marine pollution bulletin》2011,62(7):1476-1483

Eighty-five stranded or bycaught harbor porpoises collected from the Danish North Sea between 1980 and 2005 were analyzed for perfluorochemicals in the liver. PFOS was the predominant compound, making up on average 88.9% of the ∑PFC, followed by PFOSA (7.8%). PFUnA (1.9%) and PFDA (1.2%) were detected in most samples. PFHxS, PFNA and PFOA were only found in a minority of the samples. We found substantial differences in PFC concentrations among life history stages, the highest concentrations were found in neonates, suckling juveniles and lactating females. Such differences should be considered when PFC levels in wildlife are evaluated. The high concentrations found in young porpoises are of concern as PFCs have known toxic effects on the development of the central nervous system and reproductive organs. Despite efforts to reduce PFC emissions, a decreasing temporal trend of concentrations was not detected for any compound. PFCA concentrations were found to be increasing.  相似文献   

Effects of BPA and E2 on expression profiles of genes related to hypothalamic-pituitary-gonadal axis of half-smooth tongue sole Cynoglossus semilaevis     

李风铃  李兆新  王清印  翟毓秀 《中国海洋湖沼学报》2013,31(3):598-608

Endocrine disrupting chemicals (EDCs) are increasingly viewed as persistent pollutants, similar to natural hormones in function. This paper describes the expression profiles of 7 genes (DMRT, VTG, GnRHR, FSHR, CYP17A, CYP19A, and CYP19B) involved in sex steroid synthesis and action as well as sexual development in adult male and female Cynoglossus semilaevis, after exposure to different concentrations of Bisphenol A (BPA) and 17β-estradiol (E2). Both BPA (1, 10, 50, 125, and 250 mg/kg) and E2 (0.5, 5, and 10 mg/kg) induced changes in target gene expression, although the estrogenic effects of E2 as a model estrogen were stronger. Among the 7 genes, VTG, CYP17A and CYP19 responded strongly to BPA or E2 exposure and can thus serve as reference biomarkers for estrogenic EDCs exposure in marine teleosts. These data will provide a window to establish a hypothalamic-pituitary-gonadal model in C. semilaevis to better understand the effect pathways of EDCs.  相似文献   

Spatial distribution of marine chemicals along a transect from Zhongshan Station to the Grove Mountain area,Eastern Antarctica     

Xiang Qin  ChuanJin Li  CunDe Xiao  ShuGui Hou  MingHu Ding  JiaWen Ren  DaHe Qin 《中国科学:地球科学(英文版)》2014,57(10):2366-2373

This study investigates the regional distribution of marine aerosol originated species(Na+, Cl-, nss-SO42- and MSA) in the snow pits(or firn cores) collected along a transect between Zhongshan Station and the Grove Mountain area(450 km inland) on the eastern side of the Lambert Glacier Basin. Concentrations of Na+ and Cl- decrease exponentially with distance from the coast to 100 km inland(i.e., 1500 m a.s.l.). Statistical results demonstrate that distance from the coast inland and elevation affect the concentration of sea-salt originated ions in inland areas significantly. Increase of Cl-/Na+ ratio and higher variability in its standard deviation suggest that there are other sources of ions in addition to sea-salt in inland areas of the Antarctic continent. The concentrations of Na+ and Cl- from nine sampling sites in the Grove Mountain area are relatively higher than those from sites along CHINARE transect, although all sites are at similar distance inland. This phenomenon indicates that the barrier effect of the mountain may be the most important factor influencing ion deposition. In addition, nss-SO42- and MSA vary differently, with nss-SO42- decreasing with distance more significantly. This implies that sources and transporting pathways influence the deposition of the two sulfur compounds considerably, being supported by the spatial pattern of correlation coefficients between the nss-SO42- and MSA.  相似文献   

渤海湾盆地源于石炭-二叠系的煤成气成因特征和潜力分析   总被引：3，自引：0，他引：3  

金强  宋国奇  梁宏斌  程付启  王力 《地质学报》2009,83(6):861-867

渤海湾盆地是叠合在华北地台上的含油气盆地,随着勘探的深入发展,陆续发现了一些源于石炭-二叠系的煤成气资源。作者通过地球化学研究,认为具有成藏意义的煤成气是古近纪以来二次生烃过程中生成的,并且发现现今的低突起、斜坡带和洼陷带是煤成气生成和聚集有利区带。由于断裂发育,煤成气常与上覆沙河街组生成的油型气混合成藏,作者通过统计各盆地I、II和III型有机质生成的甲烷和乙烷碳同位素分馏情况,给出了煤成气和油型气鉴别图版,可以判别是否为二者的混合气。利用一级反应动力学,预测了5种构造单元煤成气生成率,发现隆起区和凸起区没有二次生气过程,洼陷带生气率已超过80％,斜坡带和低突起正处于快速生气期、并有轻质油生成。这些为进一步认识渤海湾盆地煤成气聚集和勘探潜力提供了依据。  相似文献   

吐哈盆地侏罗系煤成液态烃生成演化的热模拟实验研究   总被引：7，自引：2，他引：5  

王春东  张中宁 《地质学报》1998,72(3):276-284

利用绝对密闭式干热解方法对吐哈盆地侏罗系腐殖煤的液态烃生成演化规律进行了研究。研究结果表明,煤在低成熟阶段(R_0=0.40％～0.65％)的液态烃产率变化幅度较小、地球化学特征也保持未熟—低熟特征;热解物产率曲线在R_0=0.58％～0.59％阶段呈现一个低谷;液态烃大量生成于R_0=0.65％阶段,产率峰值出现于R_0=1.09％阶段。进一步通过热模拟产物Pr/Ph、Pr/nC_(17)、Ph/nCl_(18)及饱/芳值等参数的变化规律、热解物正构烷烃分布特征、热模拟残渣的热解色谱特征,及与典型煤成油进行对比研究.证实了侏罗系煤成液态烃主要生成并排驱于成熟阶段(R_0=0.65％～1.09％)。  相似文献   

An analysis of chemical loads and forms in overland flow from dairy pasture in South Australia     

N. K. Fleming  J. W. Cox  D. J. Chittleborough  C. B. Dyson 《水文研究》2001,15(3):393-405

Two adjacent subcatchments on soils with very strong texture contrast between the A soil horizons (sandy loam texture) and B soil horizons (clay texture) in the Adelaide Hills, South Australia were instrumented to collect overland and subsurface flow from dairy pasture. Subcatchments were defined by exclusion drains in the upper reaches and stainless steel barriers at the lower boundary. Water samples were analysed for 20 different chemical fractions. Chemical loads were examined in order to determine relationships among simple empirical event and site characteristics, and between chemical fractions. All but five of the chemical fractions could be separated into one of two clear groups using a statistical technique based on the magnitude of simple correlation coefficients. The two groups consisted of either dissolved or particulate fractions. The clear separation into these groups is consistent with the majority of chemical fractions moving from pasture by one of only two processes. Simple empirical variables in a multiple regression explained a high proportion of variation in chemical loads in runoff water. These findings may have major implications in the modelling and prediction of chemical loads in runoff from agricultural catchments and the setting of environmental limits, in simplifying chemical loss predictions by adding a nutrient loss module to runoff volume predictions. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

临清坳陷东部煤成气藏的主控因素及成藏模式   总被引：1，自引：0，他引：1  

刘晓丽 《煤田地质与勘探》2013,41(1):25-29

临清坳陷是渤海湾盆地油气资源的重要勘探研究区,其煤成气藏潜力大,但研究程度较低。从多角度入手,通过解剖典型的煤成气探井,分析研究了临清坳陷东部煤成气藏的主控因素及成藏模式。研究结果显示:该区煤岩以Ⅲ型干酪根为主,暗色泥岩以Ⅱ₂-Ⅲ型干酪根为主,易于生气（油）;油气运移以近源输导为主;煤成气成藏主要受控于圈闭的赋存条件、油气输导、生储盖组合以及优质烃源岩分布等4个方面;成藏模式主要划分为源内成藏和源外成藏两种模式,其中源内成藏模式是今后该区勘探的主体,源外成藏的I型为进一步攻克对象。   相似文献   

Product Evaluation for the Control of Chemical Emissions to Indoor Air – 10 Years of Experience with the AgBB Scheme in Germany     

Christine Däumling 《洁净——土壤、空气、水》2012,40(8):779-789

Emissions from construction products may have a significant impact on the quality of indoor air, particularly in energy‐efficient buildings, where the normal rate of air exchange with fresh ambient air may be limited. In this context, reduction strategies to mitigate the concentration of chemicals in the indoor environment have become even more important. German authorities wanted to foster the development of low‐emission products, and as a result it was necessary to quantify and qualify these emissions in a reliable and objective manner. The core principles for evaluation of the standardized measurements in emission tests were established by the “Committee for Health‐Related Evaluation of Building Products” (AgBB) and published in the so‐called “AgBB scheme”. Relevant for evaluation are: (i) Assessment of the emission levels of substances with known toxicological properties; (ii) limits for non‐assessable or unknown substances; (iii) limits for the total amount of chemical emissions. This review describes the stepwise implementation of the test procedure in Germany and the experience gained in evaluation of product emissions over the years. A comprehensive overview of the philosophy, history, current practices, and future directions of the German AgBB scheme for VOC emissions is also provided. Special emphasis is given to the evaluation of a list of about 170 single substances which have an agreed “lowest concentration of interest” (LCI) value for the indoor environment – values that are updated periodically according to present toxicological knowledge.  相似文献   

杭州城区水域中PAEs分布特征及黄颡鱼(Pelteobagrus vachelli)体内残留消除研究     

胡天宇  胡华军  韩宝瑜  葛建  姚元发  王慧  王敏君  屈叶青  袁萍 《海洋与湖沼》2013,44(2):355-359

采用气相色谱(GC-FID)检测技术,对杭州城区水体以及黄颡鱼(Pelteobagrus vachelli)肌肉和脑等可食性组织中5种PAEs类化合物进行检测,确定杭州城区水体中PAEs分布特征,并分析了PAEs在黄颡鱼肌肉和脑中含量随时间动态变化规律。研究结果表明,杭州城区水体中5种PAEs化合物含量均较高,但每种化合物含量差异较大,其中DEHP含量在不同水域中含量均最高。黄颡鱼体内残留检测结果显示,5种PAEs类化合物在黄颡鱼肌肉和脑等可食性组织中均有分布,其中脑和肌肉中的消除半衰期处于17.33—32.54h之间。结果表明,PAEs在杭州城区不同水体中广泛分布,在鱼体肌肉和脑等可食性组织中消除较缓慢。  相似文献   

Characteristics of the Acid Rain Variation in China During 1993-2006 and Associated Causes   总被引：3，自引：0，他引：3       下载免费PDF全文

ZHAO Yanxi  HOU Qing 《Acta Meteorologica Sinica》2010,24(2):239-250

The acid rain observation network of China Meteorological Administration was established in 1989 with 22 stations.From 1993 to 2005,more than 80 stations were included and maintained in the network.In 2006-2007,the number of stations in the network went up to 294.In consideration of the data continuity,data used in this paper are the 14-yr observations of the 80 stations from 1993 to 2006.Based on the 14-yr observation of acid rain,analysis shows that the acid rain in China dominates in the vast regions south of the Yangtze River.Limited presence of acid rain is observed in the northern part of China.The 14-yr acid rain data reveal an expanding tendency for acid rain area,with the north of China being a growing zone,and the South China remaining virtually unchanged.The most severely polluted zone of acid rain gradually moves from Southwest China to Central China and the middle part of South China.With regard to the acid intensity of rain,the period of 1993-1998 bears the highest acid intensity; the period of 1999-2002 shows a bit weakening intensity; and in the period of 2003 2006,the acid intensity of rain increases again,basically up to the average acidity of the period of 1993-1998 by the end of 2006.In addition,rain acidity in the north of China increases markedly.As to the causes of the acid rain situation in China,this paper examined the sulfur dioxide emissions as well as the rainwater chemicals monitoring data.  相似文献