壬基酚对奥尼罗非鱼(Oreochromis niloticus×O.aureus)的急性毒性研究

采用换水式毒性试验法研究了壬基酚(nonylphenol)对奥尼罗非鱼(Oreochromisniloticus×O.aureus)的急性毒性、遗传毒性效应和对鱼体的器官损伤。结果表明,壬基酚对奥尼罗非鱼的24、48、72和96h的半致死浓度(LC50)分别为413.4、351.5、311.2和264.6μg/L,属剧毒物质。与空白对照相比,奥尼罗非鱼血红细胞的核异常率在最低处理浓度(150.0μg/L)下有显著意义的增加,微核率在≥337.5μg/L时也开始具有显著意义的增加。不同的暴露时间和剂量对血细胞微核率和总核异常率具有不同程度的影响。壬基酚对奥尼罗非鱼的鳃、肾脏、脾、肝均造成不同程度的病理损伤。     

Use of Plant Bioassays for the Detection of Genotoxins in the Aquatic Environment

The present article describes the use of plant bioassays for the detection of genotoxins in the aquatic environment and gives an overview of test methods, their detection spectrum for environmental mutagens and carcinogens and their limitations and pitfalls. The most widely used test systems are micronucleus assays with meiotic cells of Tradescantia and with meristematic root tip cells of Allium and Vicia. In the last years, protocols for single cell gel electrophoresis assays have been developed, which can be conducted with a variety of species. Also various gene mutation test procedures have been developed with plants but they have hardly ever been used in environmental studies. Plants detect a broad variety of environmentally relevant genotoxins, in particular directly acting compounds. Many pesticides and industrial chemicals caused positive results; plant assays are also a unique tool for the detection of DNA‐reactive carcinogenic heavy metals in the environment. In many studies with complex mixtures, positive results were obtained which indicates that plants are sufficiently sensitive to detect effects without concentration of water samples. One of the shortcomings of the use of plants as indicators is their lack of sensitivity towards certain classes of promutagens such as nitrosamines, heterocyclic amines, and polycyclic aromatic hydrocarbons (PAHs). However, the former compounds are hardly encountered in the environment and PAHs can easily be detected chemically and in other mutagenicity tests. Taken together, the currently available data show that plant bioassays are a useful component of test batteries for environmental monitoring.     

Aspects of the usefulness of five marine pollution biomarkers, with emphasis on MN and lipid content

By using cellular biomarkers, such as the formation of the micronucleus, the morphometric alterations of lipids and the morphometric changes in the lysosomal system, we investigated effects of experimental exposure to phenanthrene, Cu, Cd, and Hg for 15 days in mussels. Concerning micronuclei, the evaluation of the total nuclear abnormalities, instead of the micronucleus only, as a biomarker of marine pollution, indicated more statistically significant differences between the control and the pollutant treated groups. Contrary to the existing knowledge showing that there is an increase in lipid content after pollutant exposure, our results showed that there was a decrease in the amount of lipid, as well as an increase in the number of neutral lipids. Furthermore, although prior studies found that fewer lysosomes formed after pollutant exposure, this was not confirmed by our work, as pollutant treated animals exhibited a decrease in the volume and an increase in the numerical density of lysosomes, compared to control groups.     

藻酸双酯钠(PSS)遗传毒理学效应的初步研究

本研究是用紫露草微核技术检测新药藻酸双酯钠(PSS)的遗传毒理学效应。实验结果表明,PSS没有遗传毒性,却有保护染色体免受损伤的作用。其表现是使汞离子所产生的微核率明显下降。因而为扩大PSS的临床应用范围和使用安全提供了实验依据。