Fate of pharmaceuticals--photodegradation by simulated solar UV-light

The fate of pharmaceuticals in surface waters under solar irradiation was investigated. Photodegradation of pharmaceuticals caused by sun irradiation may be of major significance in the natural elimination process. Based on a data compilation from the literature, the lipid lowering agent metabolite clofibric acid, the iodinated X-ray contrast media iomeprol, which contribute to the adsorbable organic halogen compounds, and the antiepileptic drug carbamazepine were selected. The irradiation experiments were carried out in batch experiments with simulated UV–sunlight. The photodegradation of the pharmaceuticals showed a pseudo-first-order kinetics. The objective of this investigation was to demonstrate that the extent of photoinduced degradation of pharmaceuticals can vary significantly for the different pharmaceuticals and it strongly depends on the water constituents present in solution. The influences of different initial pharmaceutical concentrations, the presence of other pharmaceuticals like carbamazepine or clofibric acid and the presence of natural organic matter on the photochemical degradation rate of pharmaceuticals in aqueous solutions were investigated. Analyses of the pharmaceuticals and their photodegradation products were carried out by high performance liquid chromatography with diode-array and fluorescence detection.     

水环境中微囊藻毒素检测技术研究进展

随着世界各国对微囊藻毒素的重视,中国也在相关水质标准里新增了微囊藻毒素这项指标.因此,水环境中微囊藻毒素的检测和控制变得非常重要,而检测更是控制的基础.比较详细地综述了目前国内外在微囊藻毒素检测方面的各种不同的研究方法和成果;并在总结这些研究的基础上,展望了微囊藻毒素检测的发展方向.     

Induced alkoxyresorufin-O-dealkylases in tilapias (Oreochromis niloticus) from Guandu river, Rio de Janeiro, Brazil

The activity of fish monooxygenases has been extensively used as a monitoring tool to detect contamination of water bodies by cytochrome P450-inducing agents. In this study we evaluated the activities of ethoxy- (EROD), methoxy- (MROD) and pentoxy- (PROD) resorufin-O-dealkylases in the liver of Nile tilapias (Oreochromis niloticus) collected at the Guandu river, at a reference clean site (Lake 1) and at two other sampling sites (Lakes 2 and 3) in Rio de Janeiro state, Brazil. Alkoxyresorufin-O-dealkylases were measured fluorimetrically in the hepatic S9 fraction. EROD (17.7-fold), MROD (14.2-fold) as well as PROD activities were considerably higher in tilapias from Guandu river. A moderate increase of EROD (5.0-fold) and MROD (5.4-fold) was also found in tilapias from Lake 3. These findings suggest that Guandu river watershed, the main source of urban drinking water supply in Rio de Janeiro, is polluted with CYP1A-inducing xenobiotics. Furthermore, we also found a good linear relationship between EROD and MROD, a finding that agrees with the hypothesis that the two reactions are catalysed by the same CYP1A isoform in O. niloticus.     

Probabilistic approaches in the effect assessment of toxic chemicals. What are the benefits and limitations?

There is an ongoing discussion whether in the environmental risk assessment for chemicals the so called 'deterministic' approach using point estimates of exposure and effect concentrations is still appropriate. Instead, the more detailed and scientifically sounder probabilistic methods that have been developed over the last years are widely recommended. Here, we present the results of a probabilistic effect assessment for the aquatic environment performed for the pesticide methyl parathion and compare them with the results obtained with the common deterministic approach as described in the EU Technical Guidance Document. Methyl parathion was chosen because a sufficient data set (acute toxicity data for about 70 species) was available. The assumptions underlying the probabilistic effect assessment are discussed in the light of the results obtained for methyl parathion. Two important assumptions made by many studies are: (i) a sufficient number of ecologically relevant toxicity data is available, (ii) the toxicity data follow a certain distribution such as log-normal. Considering the scarcity of data for many industrial chemicals, we conclude that these assumptions would not be fulfilled in many cases if the probabilistic assessment was applied to the majority of industrial chemicals. Therefore, despite the well-known limitations of the deterministic approach, it should not be replaced by probabilistic methods unless the assumptions of these methods are carefully checked in each individual case, which would significantly increase the effort for the assessment procedure.     

稀有鮈鲫Dmrt基因家族13个成员的克隆与序列分析

已经发现果蝇Doublesex、线虫Mab-3、青DMRT1Y/DMY和人类DMRT1等性别决定与分化基因均含有一个具有DNA结合能力的保守基序--DM结构域,对性别决定和性别分化具有调控功能.利用简并PCR,从稀有鲫基因组DNA中克隆了13个具有不同DM结构域的Dmrt基因家族成员.基于DM保守基序,建立了各物种的进化树.结果表明,稀有鲫基因组存在多个Dmrt基因成员,该基因在脊椎动物和非脊椎动物中具有高度保守性,是一种理想的环境内分泌干扰物研究的分子模型,在分子生态毒理学研究中具有很好的应用前景.     

Robust benchmark dose determination based on profile score methods

We investigate several methods commonly used to obtain a benchmark dose and show that those based on full likelihood or profile likelihood methods might have severe shortcomings. We propose two new profile likelihood-based approaches which overcome these problems. Another contribution is the extension of the benchmark dose determination to non full likelihood models, such as quasi-likelihood, generalized estimating equations, which are widely used in settings such as developmental toxicity where clustered data are encountered. This widening of the scope of application is possible by the use of (robust) score statistics. Benchmark dose methods are applied to a data set from a developmental toxicity study.     

我国利用水生植物监测和净化污水的研究进展

本文综述了我国利用水生植物监测和净化重金属废水、化工废水、生活污水、放射性核素废水以及抑制富营养化水体中藻类研究进展。并讨论了各种生态因子对水生植物净化效率的影响。为建立低投资、高效率、易管理的植物净化处理设施提供参考。     

辽北地区水生昆虫与水质监测试验

辽北地区水生昆虫与水质监测的试验是采用美国昆虫学家莫尔斯．约翰提出的监测模式进行的。文中重点阐明了水生昆虫的采样方法、生境观察指标、污染指数值确定方法、评价标准，并进行了应用实例分析。研究结果表明，水生昆虫监测方法适用于快速监测和评价河流水质。     

石油污染对非洲鲫鱼血清蛋白的影响

本文通过分析非洲鲫鱼清蛋白含量的变化，研究油对鱼类的致毒效应，试验结果表明，对血清蛋白影响的方式为：（１）油既能提高血清总蛋白和球蛋白含量，又能降低血清白蛋白含量和白蛋白／球蛋白的比值；（２）油对非洲鲫鱼血清蛋白产生作用的浓度阈值为０．０５ｍｇ／Ｌ。     

“大数据”预测分析与三丁基锡暴露有关疾病

通过毒理学“大数据”,挖掘三丁基锡（TBT）潜在的生物影响信息,预测分析TBT暴露与人类相关疾病的关系.通过比较毒理组学数据库（CTD）搜集到488个和TBT具有相互作用的基因.基因相互作用网络图显示TP53拥有相关联基因最多,处于中心地位;其次是ESR1和FN1.CTD分析与TBT相关的疾病,发现前10类疾病分别是癌症、神经系统疾病、心血管疾病、泌尿生殖系统疾病（女）、消化系统疾病、代谢疾病、泌尿生殖系统疾病（男）、内分泌系统疾病、免疫系统疾病、呼吸道疾病.KEGG通路和DAVID基因功能注释分析,发现TBT不仅和代谢性疾病有较高的关联性,其相互作用基因在糖代谢途径上亦有较密集的基因功能注释.PASS的活性预测也发现TBT可能影响多种与糖代谢相关的酶生物活性.这提示TBT对糖代谢相关疾病的影响应引起人们的注意.