水源水、饮用水中氯仿、四氯化碳含量与微核率相关性研究

为了解并改善饮用水质,在1991年第4季度至1993年第1季度,于某市水源水和水厂出厂水中采水样,每季度采集1次,每站位同时取两份,一份测定卤代烃的含量,一份用于处理蚕豆根尖并计数根尖细胞微核率。结果表明水厂出厂水中卤代烃含量比水源水的高,尤其是四氯化碳,各水厂出厂水中卤代烃的含量也有明显差异。发现水源水、水厂出厂水中四氯化碳含量与致突变有明显的相关性。     

稀土元素的致突变性研究

用VMT检测14种稀土元素的致突变性,结果表明：重稀土组最强,中稀土组次之,轻稀土组软弱,其阈值为1μg/mL～5μg/mL。在一定浓度下,稀土对植物生长的影响表现为蚕豆根尖发黑甚至变硬,显微镜下见纤维组织增多,细胞变小、萎缩或变形,显示稀土具有细胞毒性;大量葡萄糖介质可使稀土毒性缓解;稀土－柠檬酸络合物可使稀土致突变阈值后移     

家兔接触低浓度焦炉污染物细胞遗传损伤指标的变化

将实验动物（家兔）饲养于低浓度焦炉逸散物污染的环境中（现场B（a）P浓度2～10μg/100m³）,动态观察染毒前、现场染毒二周、四周及脱离现场一周外周血淋巴细胞姐妹染色单体交换（Sec）率和微核（MN）率的变化。结果显示,高SCE细胞（HFC）率在第二周即增高,到第四周SCE率均值也明显升高,但在脱离污染环境一周后可恢复到染毒前水平。MN率未显示变化。     

Evaluation of potential genotoxic/cytotoxic effects induced by epoxiconazole and fenpropimorph-based fungicide in bovine lymphocytes in vitro

Potential genotoxic/cytotoxic effects of the epoxiconazole/fenpropimorph-based fungicide were investigated using single cell gel electrophoresis and cytogenetic assays: chromosomal aberrations, sister chromatid exchanges, micronuclei and fluorescence in situ hybridization in cultured bovine lymphocytes. No statistically significant elevations of DNA damage and increases in cytogenetic endpoints were seen. However, evident cytotoxic effect presented as a decrease in mitotic and proliferation indices were recorded after exposure of bovine lymphocytes to the fungicide for 24 and 48 h at concentrations ranging from 3 to 15 µg mL^?1 (P < 0.05, P < 0.01, P < 0.001). Similarly, for 24 h an inhibition in the cytokinesis block proliferation index (CBPI) was obtained after exposure to the fungicide at concentrations ranging from 1.5 to 15 µg mL^?1 (P < 0.01, P < 0.001) in each donor.     

Fine atmospheric particles emitted by industrial,traffic and urban sources in France: characterization and genotoxicity

Health risks associated with inhalation of fine particulate matter of 2.5 µm in diameter or smaller depend on their atmospheric levels and physicochemical properties. The relationships between chemical compositions and genotoxic activities of particles emitted by mineral industries, traffic and urban sources during summer and winter in the region of Provence-Alpes-Côte d'Azur (France) were investigated.

The fine particles were separated in respect to water-soluble (13 minerals and metals) and organic-extractable (16 polycyclic aromatic hydrocarbons) components that were quantified. The chromosome damaging properties of the hydrophilic and lipophilic extracts were assessed using the centromeric micronucleus assay on a human lung fibroblast cell line.

The composition of the fine particulate matter was variable and depended upon the sources and seasons. Both the hydrophilic and lipophilic extracts induced chromosome damage: (1) in hydrophilic extracts, Ca and Zn affected chromosome losses induction; (2) acenapthylene affected chromosome damage (breakages and losses) induction and naphthalene affected chromosome damage and losses induction in lipophilic extracts without metabolic activation; and (3) benzo[a]pyrene affected chromosome losses induction in lipophilic extracts with metabolic activation. Fine particulate matter arising from coal-fired power station, road traffic, and other urban sources were the most efficient to induce chromosome breakage.     

氰戊菊酯与辛硫磷混合杀虫剂(农满忆)对雄性小鼠精子畸形率和生殖细胞微核率的影响

为初步探讨氰戊菊酯与辛硫磷混合杀虫剂(农满忆)对雄性小鼠生殖细胞的损伤效应,将该杀虫剂对小鼠进行灌胃染毒5d,于第6d取小鼠睾丸细胞进行微核试验并采用精子畸形实验检测小鼠不同时期(第6、14、36d)精子畸形率的改变.结果表明,与对照组相比,该杀虫剂中、高剂量组(60、120mg·kg-1)小鼠睾丸细胞微核率均显著升高(p<0.05),而低剂量组(30mg·kg-1)微核率没有显著变化(p>0.05);中、高剂量组均能诱导小鼠不同时期精子畸形率显著升高(p<0.05),而低剂量组精子畸形率变化不显著(p>0.05).因此,氰戊菊酯与辛硫磷混合杀虫剂能够使雄性小鼠精子畸形率增加并造成雄性生殖细胞微核率升高,有一定的致突变作用.     

Cytogenetic status of human lymphocytes after exposure to low concentrations of p,p'-DDT, and its metabolites (p,p'-DDE, and p,p'-DDD) in vitro

Despite that the use of DDT has been restricted for more than 40 years to malaria affected areas, low doses of this pesticide and its metabolites DDE and DDD can be found in the environment around the world. Although it has been shown that these pollutants induce cell and DNA damage, the mechanisms of their cytogenotoxic activity remains largely unknown. This study looks into their possible genotoxic effects, at doses that can be found in body fluids, on human lymphocytes using the cytokinesis-block micronucleus assay and the comet assay. After exposure for 1, 6, and 24 h compounds p,p′-DDT (0.1 μg mL⁻¹), p,p′-DDE (4.1 μg mL⁻¹), and p,p′-DDD (3.9 μg mL⁻¹) showed increase in DNA damage. The most significant results were observed at exposure period of 24 h where number of micronucleated cells increased from control 2.5 ± 0.71 to 23.5 ± 3.54, 13.5 ± 0.71, and 16.5 ± 6.36 for DDT, DDE, and DDD, respectively. Similar effect was observed using comet test where the percentage of DNA in comets tail increased from control 1.81 ± 0.16 to 17.24 ± 0.55, 11.21 ± 0.56 and 9.28 ± 0.50 for each compound, respectively. At the same time Fpg-comet assay failed to report induction of oxidative DNA damage of these pollutants. Additionally, the type of cell death was determined using diffusion assay and necrosis dominated. Our findings suggest that even at low concentrations, these pesticides could induce cytogenetic damage to human peripheral blood lymphocytes and in that manner have the impact on human health as well.     

Perfluorooctane Sulfonate Increases the Genotoxicity of Cyclophosphamide in the Micronucleus Assay with V79 Cells: Further Proof of Alterations in Cell Membrane Properties Caused by PFOS (3 pp)

Background, Aim and Scope Perfluorooctane sulfonate (PFOS; C8F17SO3-) is a fully fluorinated organic compound which has been manufactured for decades and was used widely in industrial and commercial products. The recent toxicological knowledge of PFOS mainly concerns mono-substance exposures of PFOS to biological systems, leaving the potential interactive effects of PFOS with other compounds as an area where understanding is significantly lacking. However, a recent study, reported the potential of PFOS to enhance the toxicity of two compounds by increasing cell membrane permeability. This is of particular concern since PFOS has been reported to be widely distributed in the environment where contaminants are known to occur in complex mixtures. In this study, PFOS was evaluated alone and in combination with cyclophosphamide (CPP) to investigate whether a presence of PFOS leads to an increased genotoxic potential of CPP towards hamster lung V79 cells. Genotoxicity was investigated using the micronucleus (MN) assay according to the recent draft ISO/DIS 21427-2 method. PFOS alone demonstrated no genotoxicity up to a concentration of 12.5 mg/L. However, PFOS combined with two different concentrations of CPP, with metabolic activation, caused a significant increase in the number of micronucleated cells compared to treatments with CPP only. These results provide a first indication that PFOS has the potential to enhance the genotoxic action of CPP towards V79 cells, suggesting that together with the alterations in cell membrane properties shown previously, that genotoxicity of complex mixtures may be increased significantly by changes in chemical uptake. Together with an earlier study performed by the own working group it can be concluded that PFOS alone is not genotoxic in this bioassay using V79 cells up to 12.5 mg/L, but that further investigations are needed to assess the potential interaction between PFOS and other substances, in particular regarding the impact of membrane alterations on the uptake of toxic substances. Materials and Methods: - Results: - Discussion: - Conclusions: - Recommendations and Perspectives: -     

垃圾渗滤液对蚕豆根尖细胞微核效应的研究

利用蚕豆根尖细胞微核测定技术对垃圾渗滤液的微核效应进行了监测．结果表明,填埋场垃圾的微核率为１２．７０×１０－３ ,渗滤液的微核率为（１６ ．７６ ～２９．５）×１０ －３ ．垃圾场底部０～１０ ｃｍ 处的土层已被污染,微核率为１５．３８ ×１０－３ ,与ＣＫ有显著性差异;而３０ ～４０ ｃｍ 处土层的微核率为７ ．６５ ×１０－３ ,与ＣＫ无显著性差异,提示该处土层对垃圾渗滤液中污染物向下迁移有拦截、净化作用．经过处理后的渗滤液的微核率明显降低．蚕豆根尖微核检测结果与化学分析结果相吻合,认为此法可用于对垃圾渗滤液污染状况进行生物监测．     

氨基酚对不同生物细胞微核率影响的比较观察

氨基酚类化合物属于有毒有机化合物 ,在环境中对动物和人类造成潜在的危害。为了全面评价其遗传毒理学效应 ,采用不同的生物材料 ,不同的组织细胞 ,对 3种氨基酚类化合物进行微核试验。试验结果表明 ,3种氨基酚类化合物均能引起 3种细胞微核率的增加 ,高剂量组与对照组相比有显著性差异 (P <0 .0 5 ,P <0 .0 1 ) ,且有明显的剂量 效应关系。提示 3种氨基酚类化合物具有较强的致突变效应。