Human exposure to a mixture of endocrine disruptors and serum levels of thyroid hormones: A cross-sectional study

Exposure to endocrine disruptors (EDCs) could disrupt thyroid hormone homeostasis. However, human epidemiological studies reported inconsistent observations, and scarce information on the effect of a mixture of chemicals. The aim of the present study was to examine the associations of multiple chemicals with thyroid hormones among adults from China. We measured serum levels of thyroid hormones and urinary levels of 11 EDCs, including six phthalate metabolites, bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS), perchlorate, and thiocyanate among 177 healthy adults without occupational exposure. Associations of multiple urinary analytes with serum thyroid hormones were examined by performing general linear regression analysis and bayesian kernal machine regression analysis. These EDCs were detected in almost all samples. After adjusting for various covariates, we observed only BPF significantly associated with total thyroxin (TT4) (β=-0.27, 95% confidence interval (CI) [-0.41, -0.14]), total triiodothyronine (TT3) (β=-0.02 95% CI [-0.03, -0.01]), free T4 (fT4) (β=-0.02, 95% CI [-0.03, -0.01]), and free T3 (fT3) (β=-0.04, 95% CI [-0.07, -0.01]), and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and monoethyl phthalate (MEP) positively associated with TT4 (β=0.24, 95% CI [0.01, 0.48]) and fT4 (β=0.02, 95% CI [0.01, 0.04]), respectively. Moreover, we observed significant dose-response relationships between TT4 and the mixture of 11 EDCs, and BPF was the main contributor to the mixture effect, suggesting the priority of potential effect of BPF on disrupting thyroid function under a real scenario of human exposure to multiple EDCs. Our findings supported the hypothesis that human exposure to low levels of EDCs could alter thyroid hormones homeostasis among non-occupational healthy adults.     

涡凹气浮机在炼油污水处理中的应用

对涡凹气浮机在炼油污水气浮工艺的改造的应用进行了总结，改造后该气浮机具有投资省、运行费用低、操作维护简单、工作效率高等优点，且运行稳定，效果比较理想，应用前景十分广阔。     

Climatic change and urbanization effect in China

Climatic change and urbanization effect in China during the last 39 years were investigated. It is found that a warming of about 0.23℃ for the annual temperature has been noticed from 1951 to 1989. The warmings of about 0.78 ℃ in winter and 0.34 3℃ in spring have been shown. It is also presented that a cooling of about -0.27℃ in summer has been indicated. The bigger cities are warmer than smaller cities in China. The dried trends in the annual precipitation during the last 39 years were presented. The precipitation decreased obviously in summer all over China. The bigger cities were drier than smaller cities.     

Sensitivity experiments and assessment of climatic changes in China induced by greenhouse effect

Climatic changes can be separated into two parts: natural changes -and human activity influenced on climatic changes. The observed data could not only show the effects caused by human activity. Several simulated results as simulated by the GCMs induced by the greenhouse effects in China .have been analysed. It is shown that an obvious warming of about 3-6℃ in winter and 2-5℃ in summer in China as simulated by the GCMs induced by doubling CO2 have been found. There are getting drier or wetter regions in China due to doubled CO2 as simulated by most of models. Comparing the simulated results with the observed data in China, some simulated results are able to be believed. The GCMs should be improved, especially in the regional areas.     

青藏铁路工程对高原生态环境的影响

分析了青藏铁路工程建设生态环境的特点，探讨了青藏铁路建设对沿线冻融侵蚀、植被、冻土上限、沙漠化以及野生动物的影响，最后提出了铁路建设过程中的一些环境保护意义。     

Spatial distribution of ecological security status assessment of West-Liaohe River based on geographic information system

Eco-security assessment is a hot research area in resource and environmental science, which involves data with much spatial, non-linear, and random features. Geographic information system (GIS), as a useful tool to analyze and manage spatial information, has a superior advantage in this field. A case study in the western part of the Liaohe River featuring a method of eco-security spatial differences (ESSD) based on GIS is developed in this paper. The method includes four steps: 1) developing the pressure-state-response (P-S-R) framework with site data; 2) digitizing West-Liaohe River and setting its GRID database of ecosecurity assessment indicators; 3) figuring out the relative membership degree (RMD) of eco-security indicators by using the analytical hierarchy process with the weight of indicator; 4) classifying the security zone and mapping the assessment result of eco-security status in grid by GIS method of assigning and clustering. The visual spatial differences of eco-security based on GIS enables decision makers to know the status of eco-security better in making policies for achieving sustainability. __________ Translated from Environmental Science, 2005, 26(5): 28–33 [译自: 环境科学]     

新疆农用地变化的环境效应

土地生态环境问题一直都是专家、学者研究的热点话题,土地利用的生态环境效应更是人们日益关注的问题,以新疆1996-2004年农用地详查数据为依据,在分析研究土地利用的变化特点的基础上,阐述了农用地变化产生的环境效应.尽管农用地数量在整体上是增加的,但是土地沙化、退化,水土流失、生物多样性减少等一系列生态环境恶化现象仍在继续.因此,新疆农用地要在水资源的承载范围内适度增加.目前,新疆农用地变化给整体环境带来负面的效应,仅使局部生态环境改善,整体环境变坏.因此,新疆在土地利用中,要以此为鉴,加强生态环境建设,注重各种功能用地的结合.     

古尔班通古特沙漠1970-2000年代生物结皮覆盖变化研究

生物结皮是古尔班通古特沙漠主要的地表覆盖类型,也是维持其地表稳定的重要生物因子。论文利用20世纪70年代中期、80年代末期及21世纪初的遥感影像,通过生物结皮指数提取了古尔班通古特沙漠在相应时期内的生物结皮空间分布。在此基础上,分析了研究区近30年来生物结皮空间分布的变化特征;利用景观分析软件Fragstats计算了各个时期内结皮覆盖的景观指数熏并对其变化特征进行了分析。结果表明:由于新疆气候增湿、增暖明显,近30年来结皮发育良好。但由于油田开采、水利工程建设、牲畜放牧等人类活动的加强,结皮发育受到较为严重的干扰,区域内结皮斑块破碎化程度加大。     

膜生物反应器技术的研究和应用展望

膜生物反应器是将膜分离技术与生物上结合而开发的新型系统，该文就膜生物反应器的特征、研究现状、不同形式反应器的技术参数与处理效果等。进行了综述、由于膜生物反应器具有明显的优点，故愈来愈受到人们的重视、成为研究的热点之一。膜生物反应器的研究和范围不断拓宽，有的已进入污水处理实用阶段，建议今后在开发适合于分离的特种膜方面，在组件形式，操作条件，清洗方式等对膜通量的影响方面，以及生物作用与膜分离工艺的相互     

环境化学污染对人类的生殖危害

目前认为，环境化学物污染已对人类生殖造成一定的有害影响，综述近年来国内外有关环境中金属元素、有机化学品、气体及农药等化学物质对人类生殖影响的研究报道，为进一步开展环境生殖研究提供参考。