共查询到19条相似文献,搜索用时 156 毫秒
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近十年来,中国科学院生态环境中心竺乃恺用诱变性测定来检验环境因素的潜在致癌性,以其强度表示和比较总的生物毒性和污染程度。并认为,这样做比单一致癌物浓度表示污染程度更具有代表性。他们用上述方法研究了大气飘尘,并测定了北京不同类型地区大气飘尘的诱变性。结果表明,飘尘中存在有直接致突变物和代谢致突变物,其诱变性强度上污染程度、典型致癌物的含量及肺癌的发病率相关。并且随季节变化 相似文献
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大气颗粒物致突变性研究 总被引:9,自引:0,他引:9
对上海市10个大气采样点的飘尘,应用Ames试验进行致突变性研究。结果表明,各点试样对TA_(98)和TA_(100)菌株加或不加S_9的致突变性,均出现阳性结果;其中,尤以TA_(98)不加S_9最为敏感。飘尘剂量与回变菌落数,均呈良好的线性关系。飘尘中均含有直接和间接致突变物,且以直接致突变物的作用更强些。各点每微克飘尘净回变菌落数,基本处于同一数量级;而空气净回变菌落数则为89.2~259.2个/米~3。 相似文献
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北京地区大气飘尘的化学特性 总被引:3,自引:2,他引:3
选择北京地区7—9个采样点(五个功能区),用大容量采样器按季定期采集飘尘样品(103个)。用x射线荧光、x射线衍射、原子吸收、等离子体发射光谱等方法分析了飘尘中21种元素,并鉴定了α-SiO_2(α-石英)和CaCO_3(方解石)的物相。用元素相对浓度(x/Fe或x/Si)和富集因子(EF地壳以Fe为参比元素)进行了数据处理与分析,阐明了北京大气飘尘的化学特性以及不同地区、不同季节的差异与变化。根据分析结果认为,北京地区飘尘中的主要化学组分大都来源于自然界风砂或土壤;在飘尘中富集最高的元素S、Zn、Pb等可能主要来自人为污染源。估算了飘尘中风砂所占比例约为33%、硫酸根约为6%。 相似文献
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随着环境医学的发展,人类对环境污染问题的认识已不仅仅注意一般急、慢性中毒,环境污染对人群健康的远期潜在影响(致癌、致畸、致突变作用)越来越引起人们关注。目前广泛认为,城市环境与癌症高发有关,大气飘尘及其多环芳烃致癌物的含量与居民肺癌死亡率的增高呈正相关关系。因此,监测分析城市大气飘尘上吸附的各类有机物的致突变性,对于评价城市大气污染对居民健康特别是致癌作用的影响具有十分重要的意义。本文报告、讨论了我们利用Ames试验对昆明市大气飘尘有机提取物致突变性进行研究的结果。 相似文献
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《环境科学文摘》2001,(6)
菌株的平皿掺人试验,均诱发显示阳性反应;其中对壬基酚、2,6一二甲基苯酚、4一辛基酚等烷基酚类化合物呈强阳性反应,怀疑这12种化合物具有强致突变性,且以碱基移码型突变为主。表1参7X182(X) 103239有机烷酚类化合物致突变性研究/刘征涛(中国环科院)…//环境科学研究/中国环科院一2001,14(3)一1一3环图X一6 采用鼠伤寒沙门氏菌致突变试验(Ames予est)菌株TA97,1该98、TAloo、TA102,对环境中潜在内分泌激素干扰污染物甲基苯酚等12种烷酚类有机物的致突变性进行研究。结果表明,除2,4-二氯苯酚外,烷酚类化合物对Ames试验中TA98X182(X) 103… 相似文献
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《Atmospheric Environment. Part A. General Topics》1993,27(10):1609-1626
Bioassay-directed fractionation based upon a modification of a published technique is applied to the study of three seasonal composites of dichloromethane extracts of inhalable particulate matter collected in Newarks, New Jersey The “profiles” of mass distribution and Salmonella TA98 mutagenic activity vs polarity are similar for the three seasons. Only at the second and especially the third fractionation levels are significant differents seen with a slight shift toward more polar compounds during summer. In all three seasons, polar neutral compounds make the greatest contribution toward mutagenic activity. Hydroxynitropolyciclic aromatic hydrocarbons are difficult to analyse by GC/MS) (El and negative chemical ionization), but HPLC/UV appears to be useful. A number of techniques are emplited in the analysis of specific compounds and classes of compounds. Subsequent acetone extraction of filters yields highly polar mutagens where the acidic fractions account for most of the mutagenic activity. These compounds show significantly enhanced mutagenic activity with TA100 relative to TA98 suggesting the presence of highly polar, acidic substances that are strong alkylating agents. The compound 2-acetoxyl-1-nitronaphthalene, found in fresh diesel particalates, is shown to hydrolyse during fractionation, thus introducing a note of caution into the use of such procedures. 相似文献
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柴油机排出颗粒物致突变性研究 总被引:3,自引:0,他引:3
采用Ames试验,检测6种国产和进口牌号柴油机排出颗粒物的诱变性,研究发现,6种柴油机排出颗粒物均呈阳性,其颗粒提取物和诱变性之间,存在剂量一反应关系。Ames试验结果,主要引起TA98-S9的回变菌落落数加,显示受试物中含有移码型直接致突物,试验还发现,国产和进口柴油机排出颗粒物的致突突变性,在怠速和加速工况下,其诱变活性有一定差异。 相似文献
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大气颗粒物中多环芳烃的污染特征及来源识别 总被引:18,自引:3,他引:15
研究了北京市2000年采暖期和非采暖期2个典型代表月(6月和12月)不同粒径颗粒物的质量浓度特征以及不同粒径颗粒物中ρ(PAHs)分布特征,并同时利用比值法和化学质量平衡(CMB)受体模型对可吸入颗粒物(PM10)中PAHs的来源进行识别和解析.研究结果表明:北京市采暖期ρ(颗粒物)明显高于非采暖期;采暖期和非采暖期不同粒径颗粒物的比例有差别,采暖期、非采暖期ρ(PM10)分别约占ρ(TSP)的0.662和0.734;PAHs具有更明显富集于细颗粒物中的特征;源解析结果表明燃煤污染和机动车污染是PM10中PAHs的最主要来源. 相似文献
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《Atmospheric Environment. Part B. Urban Atmosphere》1990,24(2):267-274
The mutagenicity and benzo(α)pyrene (BαP) content of airborne particles (172 samples) from four locations in Athens was studied for 1 year starting February 1984. All the organic extracts of airborne particulate matter showed direct mutagenic activity. There was a good correlation between BαP concentration and mutagenicity in all samples. Higher values of mutagenic activity and BαP concentrations were found at the sites located in the center of the city than at the sites located in the industrial areas. The height of the sampling place has a negative effect on both measured pollution parameters. The higher percentage of biological and chemical parameters were associated with particles <3.3 μm in diameter. The mean yearly values of mutagenic activity of airborne particulates and BαP levels, were 1.9 rev m−3 and 2.6 ng m−3, respectively and can be grouped among the median, between the heavily and the lightly polluted cities of the world. Higher values of mutagenic activity were found during winter months. From the diurnal variation of mutagenic activity it was found that maximum value occurred during morning (0900–1100). The main source of mutagens seems to be the emissions from diesel powered engines and central heating. 相似文献