Gasoline-derived methyl tert-butyl ether as a potential obesogen linked to metabolic syndrome

正The power and efficiency of gasoline engines is often improved through the use of fuel with high octane ratings.The octane rating of fuel could be further increased with oxygenate additives such as alcohols and ethers, with methyl tert-butyl ether (MTBE) being one of the most common gasoline additives. The Agency for Toxic Substances and Disease     

城市污水处理厂内分泌干扰物浓度分布和去除规律

采集南方某城市3个污水处理厂进出水及各工艺单元的水样,通过固相萃取-衍生化过程对水样进行预处理,并用气相色谱-质谱联用仪定量检测水样中的17α-雌二醇(17α-E2)、雌酮(E1)、雌二醇(E2)、雌炔醇(EE2)、雌三醇(E3)、辛基酚(OP)、正壬基酚(NP)和双酚A(BPA)等8种内分泌干扰物(EDCs).连续4个季度的分析结果显示,3个污水厂进出水及各工艺单元中均有EDCs检出,EE2和BPA是含量最高的两种EDCs,出水中最高浓度分别达到498.9ng.L-1和2652.5ng.L-1,其他6种EDCs浓度均不超过100ng.L-1;生物处理工艺对EE2、E3、NP、OP和BPA有较高的去除率,平均去除率约为57%～85%,但对于E1、E2和17α-E2的去除率较低且不稳定;一级处理工艺对EDCs仅有低于18%的去除率;紫外辐照消毒工艺对EDCs的去除没有明显效果;EDCs浓度季节差异显著,由于雨水的稀释作用,旱季浓度约为雨季的2.5～7.8倍.本文对于了解我国南方地区污水处理工艺中EDCs类物质的分布和转化特点有一定的参考意义.     

电子商务能改善农业生产的环境负效应吗?-来自上海青浦的证据

电子商务在农村农业领域的快速发展带动了农民收入的增加,但是其作用路径和环境效应有待检验.以上海市青浦区为典型案例,利用264份新型农业经营主体的问卷调查数据,采用IV-ordered Probit模型和夏普利值分解法,研究了"电子商务+农业"模式的经济效应和环境效应.结果表明：电子商务的引入具有显著的农民增收效应,但主要以产量扩大型传导机制为主,反而加剧了农业生产的环境负效应.电子商务并非农民增收的关键因素,其贡献率仅为12%;发挥决定性作用的是新技术、新方法的应用带来的效率提升,以及生产规模扩大带来的规模经济效应,相应的夏普利分解贡献了达到31%和25%.这表明当前的"电子商务+农业"模式仍处于初级发展阶段,需要加强相应的规制和引导,实现从产量驱动阶段向质量驱动阶段转型.     

A monoclonal antibody against Lates calcarifer vitellogenin and a competitive ELISA to evaluate vitellogenin induction after exposure to xenoestrogen

A monoclonal antibody specific to sea bass(Lates calcarifer) vitellogenin(VTG) was developed,for use as a tool for monitoring endocrine disrupting chemicals(EDCs). VTG was induced in sea bass by intramuscular injection of 17β-estradiol(E_2: 2 mg/kg) every three days. Blood was collected three days after the last injection. Plasma VTG was then purified by chromatography in hydroxyapatite and a sephacryl-S300 column. Characterizations of purified VTG were done by phospholipoglycoprotein staining on a native-PAGE with confirmation by mass spectrometry(LC-MS/MS). Antibody was raised in mice by injection of purified VTG. After monoclonal antibody production, the hybridoma clone No. 41(MAb-sea bass VTG 41)was selected and developed for quantification of VTG by competitive enzyme-linked immunosorbent assay(ELISA). The ELISA method was sensitive with a detection limit of VTG 40 ng/mL. MAb-sea bass VTG 41 was specific to VTG from E_2-treated sea bass and others EDCs(Nonylphenol, Benzo[a]pyrene and CdCl_2). Moreover, cross-reactivity was also found in E_2-treated coral grouper(Epinephelus corallicola). The ELISA method obtained from this work can be further applied for the assessment of EDCs in Thailand and Southeast Asia's aquatic environment.     

海洋工程用新型牺牲阳极设计与性能研究(Ⅴ)——导管架平台阴极保护设计探讨

目的 针对不同设计使用年限的导管架平台,通过对比新型阳极和常规阳极用量来评价新型阳极的优势和不足。方法 针对设计寿命15年和30年的导管架平台,计算满足不同阶段保护电流需求的新型阳极和常规阳极的需求量。结果 当导管架平台设计年限较短,比如15年,牺牲阳极用量由初期保护电流需求量决定,新型阳极的使用可以达到节约阳极用量的目的。当设计年限较长,比如30年,牺牲阳极用量则由维持电流需求量决定,采用新型阳极并不能节约阳极用量。结论 并非所有设计年限的导管架平台使用新型阳极都能达到节约用量的目的,具体要根据实际计算结果而定。     

黄土高原水土流失治理若干问题的反思

本文通过对黄土高原半个世纪治理的反思 ,认为区域产业结构的调整及城市化水平的迅速提高是解决水土流失加剧及环境恶化的根本。同时 ,文章对小流域综合治理模式进行了总结 ,并提出黄土高原水土流失治理在区域综合发展、机制创新、资金筹措等方面应遵循的原则     

红肉猕猴桃新品种的选育研究

本文介绍了新选育的给网猕猴桃新品种。该品种子房鲜红色，果实横切面呈红，黄绿相间的图案；果实较大，平均单果重９２．５ｇ，最重达１５０ｇ，含糖量高，味甜，可溶性固形含量为１９．６％，总糖１３．４５％，总酸０．４９％，ＶＣ１３５．７７ｍｇ／１００ｇ，糖酸比２７．４５。     

论北京城市建设的综合减灾问题

本文针对北京城市建设面临的自然与人为灾害背景,简要论述了北京地震、水灾、火灾及“新致灾源”的历史及现状,强调开展首都圈灾害研究及减灾规划设计的重要性,并提出了系统的减灾方略及相应的管理构想。     

Perfluorinated Surfactants in Surface and Drinking Waters (9 pp)

Background, Aim and Scope In this paper recent results are provided of an investigation on the discovery of 12 perfluorinated surfactants (PS) in different surface and drinking waters (Skutlarek et al. 2006 a, Skutlarek et al. 2006 b). In the last years, many studies have reported ubiquitous distribution of this group of perfluorinated chemicals, especially perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in the environment, particularly in wildlife animal and human samples (Giesy and Kannan 2001, Houde et al. 2006, Prevedouros et al. 2006). Perfluorinated surfactants (e.g. PFOS and PFOA) have shown different potentials for reproductory interference and carcinogenity in animal experiments as well as partly long half-lives in humans (Guruge et al. 2006, FSA UK 2006a, FSA UK 2006b, 3M 2005, OECD 2002, Yao and Zhong 2005). They possess compound-dependent extreme recalcitrance against microbiological and chemical degradation and, in addition, they show variable potentials for bioaccumulation in animals and humans (Houde et al. 2006). Materials and Methods: Surface and drinking water samples were collected from different sampling sites: - Surface waters: samples taken from the rivers Rhine, Ruhr, Moehne and some of their tributaries. Further samples were taken from the Rhine-Herne-Canal and the Wesel-Datteln-Canal. - Drinking waters: samples taken in public buildings of the Rhine-Ruhr area. After sample clean-up and concentration by solid-phase extraction, the perfluorinated surfactants were determined using HPLC-MS/MS. Results: All measured concentrations (sum of seven mainly detected components) in the Rhine river and its main tributaries (mouths) were determined below 100 ng/L. The Ruhr river (tributary of the Rhine) showed the highest concentration (94 ng/L), but with a completely different pattern of components (PFOA as major component), as compared with the other tributaries and the Rhine river. Further investigations along the Ruhr river showed remarkably high concentrations of PS in the upper reaches of the Ruhr river and the Moehne river (tributary of the Ruhr) (Ruhr: up to 446 ng/L, Moehne: up to 4385 ng/L). The maximum concentration of all drinking water samples taken in the Rhine-Ruhr area was determined at 598 ng/L with the major component PFOA (519 ng/L). Discussion: The surface water contaminations most likely stem from contaminated inorganic and organic waste materials (so-called 'Abfallgemisch'). This waste material was legally applied to several agricultural areas on the upper reaches of the Moehne. Perfluorinated surfactants could be detected in some suchlike soil samples. They contaminated the river and the reservoir belonging to it, likely by superficial run-off over several months or probably years. Downstream, dilution effects are held responsible for decreasing concentrations of PS in surface waters of the Moehne and the Ruhr river. In analogy to the surface water samples, PS (major component PFOA) can be determined in many drinking water samples of the Rhine-Ruhr area where the water supplies are mainly based on bank filtration and artificial recharge. Conclusions: The concentrations found in drinking waters decreased with the concentrations of the corresponding raw water samples along the flow direction of the Ruhr river (from east to west) and were not significantly different from surface water concentrations. This indicates that perfluorinated surfactants are at present not successfully removed by water treatment steps. Recommendations and Perspectives: Because of their different problematic properties (persistence, mobility, toxicity, bioaccumulation), the concentrations of specific perfluorinated surfactants and their precursors in drinking waters and food have to be minimised. Therefore, it is of utmost importance to take the initiative to establish suitable legal regulations (limitations/ban) concerning the production and use of these surfactants and their precursors. Furthermore, it is indispensable to protect water resources from these compounds. A discussion on appropriate limit values in drinking water and foodstuffs is urgently needed. Concerning the assumed soil contamination, the corresponding regulation (Bioabfall-Verordnung 1998 – Regulation on Organic Waste 1998) should be extended to allow the control of relevant organic pollutants.     

The Precautionary Principle and Chemicals Regulation: Past Achievements and Future Possibilities (8 pages)

Background, Aim and Scope

The paper investigates the development of the institutional basis of the present modes of chemicals regulation and management, with special attention to interrelations with the precautionary principle. Main Features: The paper elucidates on how the precautionary principle has been shaped in relation to chemicals regulation and management since Carson's Silent Spring (years before the principle was confirmed as a policy-principle in German and European legislation. Furthermore, it is examined how the precautionary principle interacted with the development of the present chemicals regulatory regime, in a complex interplay within the OECD and Member Countries. The present modes of precaution in the new EU chemical legislation – REACH – are investigated with respect to the precautionary principle, and tested against two contemporary problems; brominated flame retardants and endocrine disrupting substances. Results: The analysis demonstrates the changing character of the integration of the precautionary principle. The main tendencies are from implicit to more explicit precaution and from a closed expert-orientation towards a more deliberative approach to scientific knowledge and uncertainty. The results demonstrate that the precautionary principle is manifest in both the design of the testing strategy and in policy provisions. In particular, the substitution of hazardous substances with less hazardous is important. Discussion: Despite explicit attention to the precautionary principle, is the present reformulation of the European Chemicals policy in danger of falling into loop-holes that equal problems related to the present regulation of existing chemicals? 'Precaution' has been reduced virtually to an abstract concept that is more or less devoid of practical meaning in the regulatory process. Conclusions: It is concluded that the role of the precautionary principle in chemicals regulation will require continued scrutiny in the future shaping of the REACH strategy. Perspectives: Continued development of robust and precaution-based chemicals regulation will have to involve both new data-generation strategies and new forms of political decision-making, with special attention given to transparency and deliberative policymaking.