彗星试验检测区域水源有机污染致突变量(Study on Mutagenic Threshold of Organic Pollutants in Typical Water Area by Comet Assay)

采用彗星试验检测了区域水源有机污染对人血淋巴细胞的致突变性,探讨了水源风险的评价方法.结果表明:Cr(VI)对人外周血淋巴细胞有强的致突变作用,并具有明显的剂量-效应关系;Cr(VI)剂量的对数与人外周血淋巴细胞DNA损伤的程度呈线性相关.可以用Cr(VI)作为阳性参照物量化表征水中有机污染混合物对人血淋巴细胞的致突变性.现行《地表水环境质量标准》、《污水综合排放标准》中Cr(VI)的限值可以用于评价水体中有机污染对人体健康的风险.     

盐酸小檗碱对小鼠脾细胞的DNA损伤和氧化性损伤

为了探讨盐酸小檗碱对小鼠的DNA损伤和氧化性损伤.随机选取30只小鼠分成对照组以及7.5,15,30,60与120mg· kg-1实验组,处理后,应用小鼠脾细胞进行彗星实验与抗氧化酶实验.测定DNA损伤情况以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性以及丙二醛(MDA)含量变化.对盐酸小檗碱的DNA损伤与氧化性损伤作用进行比较研究.研究结果表明:彗星实验中,随着盐酸小檗碱浓度的增加,尾部DNA含量、尾长与尾矩均增加,与阴性对照组相比差异有统计学意义(p ＜0.05或p＜0.01),且呈剂量-效应关系;超氧化物歧化酶(SOD)与过氧化氢酶(CAT)活性随盐酸小檗碱剂量增加逐渐降低,丙二醛(MDA)含量明显上升,过氧化物酶(POD)活性在7.5 mg·kg-1时上升,而后逐渐下降.在60 mg·kg-1和120 mg· kg-1时,有极显著性差异(p＜0.01)产生.由此可见,盐酸小檗碱对小鼠脾细胞有一定的损伤作用,能够引起小鼠脾细胞的DNA损伤和氧化性损伤.     

三氯生和三氯卡班对人体肝细胞DNA损伤的研究

三氯生（TCS）和三氯卡班（TCC）作为优良的抗菌和消毒剂,在药物和个人护理用品中广泛使用。近几年来,TCS和TCC在各种环境介质和生物体中被频繁检出,并引起国内外环境科学工作者的重点关注。目前,有关TCS和TCC对水生生物的毒性研究已有大量的报道,其对人体健康危害的报道仍较少。为了评估TCS和TCC对人体的遗传毒性,利用彗星实验研究两种污染物对正常人肝细胞（L02）DNA的损伤效应。结果发现：三氯生和三氯卡班皆能引起人体肝细胞的DNA损伤,并呈现显著的剂量-效应关系和时间效应关系。相比于TCS而言,L02细胞对TCC更为敏感,在低暴露剂量（2.38μmol.L-1）下就可以引起DNA断裂损伤。该结果有助于进一步揭示TCS和TCC对人体毒害的机制,更全面的评估两种污染物对人体健康的风险。     

纳米银和PVP包被纳米银对HepG2细胞遗传毒性的比较研究

为了探讨纳米银对HepG2细胞DNA损伤、染色体畸变等遗传毒性指标的影响,以期为纳米银体外遗传毒性评价提供参考依据,本文采用2种纳米银材料(20 nm-PVP包被纳米银、20 nm-无包被纳米银),分别以20μg·mL~(-1)、40μg·mL~(-1)、80μg·mL~(-1)、160μg·mL~(-1)的剂量对HepG2细胞染毒24 h,用Hoechst-33258染色法检测细胞凋亡,彗星实验检测DNA损伤,胞质分裂阻滞微核细胞组学试验法检测染色体畸变。结果表明,20 nm Ag NPs组在160μg·mL~(-1)时引起细胞凋亡数显著增多(P0.05);20 nm PVP-Ag NPs组在80μg·mL~(-1)和160μg·mL~(-1)剂量组中细胞凋亡数显著增多(P0.01)。2种纳米银引起HepG2细胞发生细胞凋亡,并呈剂量效应关系。彗星试验结果表明,20 nm Ag NPs和20 nm PVP-Ag NPs在40μg·mL~(-1)、80μg·mL~(-1)、160μg·mL~(-1)剂量组中,Olive尾矩、尾长和尾部DNA百分比与空白对照组相比均有显著差异(P0.05)。2种纳米银对HepG2细胞DNA损伤程度为:20 nm Ag NPs20 nm PVP-Ag NPs。胞质分裂阻滞微核细胞组学试验结果表明,2种纳米银均不会引起核质桥数发生明显改变(P0.05),20 nm Ag NPs在高染毒剂量下引起微核总数、I型微核、II型微核、核芽数明显升高(P0.05);20 nm PVP-Ag NPs在各染毒剂量下均会引起微核总数及I型微核数量升高(P0.01),II型微核数在160μg·mL~(-1)剂量下升高明显(P0.01),剂量大于20μg·mL~(-1)时核芽数升高(P0.01)。20 nm PVP-Ag NPs对细胞核的影响大于20 nm Ag NPs(P0.05)。总之,2种纳米银材料均会引起HepG2细胞DNA损伤及染色体畸变等遗传毒性效应的改变,无包被纳米银比PVP包被纳米银更容易引起DNA损伤,PVP包被纳米银比无包被纳米银更容易引起细胞染色体畸变相关效应;2种材料对HepG2细胞的损伤存在浓度-效应关系,浓度越高遗传毒性损伤越严重。     

铀胁迫对大豆与玉米幼苗细胞DNA损伤的彗星试验研究

以铀浓度为1000 μmol·L-1、800 μmol·L-1、600 μmol·L-1、400 μmol·L-1、200μmol·L-1和100μmol·L-1的6组铀溶液和对照组(0μmol·L-1)培养大豆和玉米幼苗,采用彗星试验研究铀胁迫对大豆和玉米幼苗细胞DNA的损伤情况.试验结果表明,铀浓度为1 000 μ...     

Effect of fomesafen on glutathione S-transferase and cellulase activity and DNA damage in the earthworm (Eisenia fetida)

Biochemical responses and DNA damage of earthworm (Eisenia fetida) exposed to various concentrations of fomesafen (0, 10, 100, and 500 μg kg^?1) for 3, 7, 14, 21, and 28 days were investigated in vivo. Glutathione S-transferase (GST) activity was significantly stimulated upon treatment with 500 μg kg^?1 fomesafen for 21 days, while the cellulase activity was markedly inhibited after 14 days of treatment. On day 28, the activities of GST and cellulase had recovered to the level similar to that of controls. Low or mild DNA damage in earthworm was induced within 14 days of exposure, and the damage was reduced or disappeared with the extension of exposure.     

彗星实验检测新农药呋喃虫酰肼对小鼠细胞DNA的损伤(Damaging Effects of Pesticide JS-118 on DNA of Mice Cells Measured by the Single Cell Gel Electrophoresis Assay)

应用彗星实验检测了新农药呋喃虫酰肼(JS-118)对小鼠脾细胞和睾丸细胞的DNA损伤,并比较了这两种细胞对呋喃虫酰肼的敏感性.体外染毒1.5h后,进行单细胞凝胶电泳,然后EB染色并用CASP分析图像.结果表明,呋喃虫酰肼在各个剂量浓度(100、200、500、1000mg·L-1)都会引起睾丸细胞DNA损伤(与对照组均具有显着性差异,p<0.05),且存在明显的剂量-效应关系;而呋喃虫酰肼在较高剂量浓度(200、500、1000mg·L-1)可引起脾细胞DNA损伤(与对照组均具有显着性差异,p<0.05),且存在明显的剂量-效应关系.与脾细胞相比,睾丸细胞对呋喃虫酰肼更为敏感.     

敌百虫致小鼠外周血淋巴细胞DNA-蛋白质交联作用研究

为探讨敌百虫致DNA-蛋白质交联作用,以昆明小鼠为受试动物,敌百虫按0、20、40、60 mg·kg-14个剂量水平,灌胃染毒小鼠2周。第5组以提取的正常小鼠外周血淋巴细胞经50μmol·L-1的H2O2处理为阳性对照组。采用经改进的彗星试验方法来检测染毒后外周血淋巴细胞DNA-蛋白质交联效应。结果表明,与空白组相比,各敌百虫染毒组都能引起DNA损伤作用(P0.01)并引起一定程度的DNA-蛋白质交联效应,在较高浓度(40、60 mg·kg-1)时DNA-蛋白质交联尤为明显,存在一定的潜在突变风险。     

蚯蚓体腔细胞彗星试验检测阿散酸在泥浆体系中降解前后的遗传毒性变化

配制不同浓度的阿散酸标准液,与某养猪场附近的表层土壤混合形成泥浆系统,放在摇床上连续培养30d.在第0、1、2、3、4周取出适量降解液,分别用分光光度法测定阿散酸的降解率;用彗星试验检测降解液对赤子爱胜蚓体腔细胞DNA的损伤.结果表明,阿散酸低浓度时在泥浆体系中能被较快降解,500mg/L的降解率达到了25%;蚯蚓体腔细胞彗星试验表明,所有降解液均具有遗传毒性,可导致蚯蚓体腔细胞DNA明显损伤,与对照相比具有显著性差异(P<0.05).图1表1参17     

芹菜素对丙烯腈引起大鼠精子脂质过氧化和DNA损伤的影响

分析芹菜素(apigenin,AP)对丙烯腈(acrylonitrile,ACN)引起的大鼠精子脂质过氧化和DNA损伤的影响,并探讨其可能的机制。将50只SPF级SD成年雄性大鼠随机分为阴性对照组(玉米油)、ACN组(50 mg·kg~(-1)ACN)、低AP组(50 mg·kg~(-1)ACN+234 mg·kg~(-1)AP)、高AP组(50 mg·kg~(-1)ACN+468 mg·kg~(-1)AP)、N-乙酰半胱氨酸(N-acetylcysteine,NAC)组(50 mg·kg~(-1)ACN+300mg·kg~(-1)NAC),以5 m L·(kg bw)~(-1)灌胃染毒,1次·d~(-1),6 d·周~(-1),连续13周。检测大鼠精子活性氧(ROS)、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性以及精子DNA损伤情况。结果发现,ACN组、低AP组、高AP组、NAC组精子ROS、MDA含量显著升高,SOD活力显著降低,精子尾部DNA含量百分比、尾长、尾距、Olive尾距均显著增高于对照组(均P0.05);而低AP组、高AP组、NAC组精子ROS、MDA含量、SOD活性和精子DNA损伤情况与ACN组相比差异均无统计学意义(P0.05)。提示ACN可引起大鼠精子脂质过氧化和DNA损伤,而AP、NAC对其无干预作用。     

Effects of benzo(k)fluoranthene,a polycyclic aromatic hydrocarbon on DNA damage,lipid peroxidation and oxidative stress in marine gastropod Morula granulata

Benzo(k)fluoranthene [B(k)F] is one of the widespread priority pollutants of polycyclic aromatic hydrocarbons that has been scarcely studied for exposure assessment. With studies reporting a high amount B(k)F in sediments and water samples around the world, it has become vital to study its effects on aquatic organisms. In this connection, this study is conducted to study the effect of different concentrations of B(k)F (1, 10, 25 and 50?µg/L) in marine gastropod Morula granulata exposed in vivo for 96?h. A concentration-dependent increase in percentage tail DNA (TDNA) as measured by comet assay was observed in snails exposed to B(k)F. Exposure concentrations above 1?µg/L B(k)F showed significant increase in superoxide dismutase (SOD) activity and lipid peroxidation value in snails. After 96?h, SOD activity was found to be doubled for 50?µg/L B(k)F in comparison to control. A significant increase in catalase and glutathione S-transferase activity was observed at all exposure conditions at the end of the exposure time. Our study showed that B(k)F induces oxidative stress in snails which further lead to genotoxic damage. To our knowledge, this is the first study on oxidative stress and genotoxic damage in gastropods exposed to B(k)F.     

Oxidative stress and genotoxicity of 1-methyl-3-octylimidazolium chloride on loach (Misgurnus anguillicaudatus)

This study was a preliminary step to evaluate the acute toxicity of 1-methyl-3-octylimidazolium chloride ([C₈mim]Cl) on loach (Misgurnus anguillicaudatus) by determining the effects on hepatic antioxidant enzyme activities and by the comet assay. The results showed that [C₈mim]Cl had acute toxicity at concentrations above 20 mg L^?1, inducing oxidative stress and genotoxicity on fish liver cells. In respect to enzyme activities, [C₈mim]Cl induced changes in the activities of superoxide dismutase, catalase, and glutathione content the livers of fish exposed at 20–80 mg L^?1. [C₈mim]Cl at the same exposure level caused a remarkable increase in malondialdehyde level. The comet assay indicated that [C₈mim]Cl at 20–80 mg L^?1 induced genotoxicity in liver cells. With increased exposure concentration and time, the two comet parameters trailing rate and tail moment were significantly increased, with significant differences (P < 0.05) observed between control group and each treatment group. The present study shows that ionic liquids can be a threat to the health of aquatic organism when accidentally released to aquatic ecosystems.     

基于彗星实验的洛克沙胂对秀丽隐杆线虫胚胎细胞DNA损伤的研究

为评价洛克沙胂的遗传毒性,采用单细胞凝胶电泳(彗星实验),研究了不同浓度的洛克沙胂对秀丽隐杆线虫胚胎细胞脱氧核醣核酸(DNA)的损伤作用。提取秀丽隐杆线虫的胚胎细胞,分别暴露于0(空白对照)、50、250、500μg·L~(-1)含洛克沙胂的溶液染毒1 h。用彗尾DNA百分比含量(TDNA%)、彗星尾长(TL)和Olive尾矩(OTM)作为DNA损伤的指标。实验结果表明,与空白对照组比较,处理组中彗尾DNA百分比含量、彗星尾长以及Olive尾矩显著增加(P0.01)。随着洛克沙胂浓度的增加,彗尾DNA百分比含量、彗星尾长以及Olive尾矩逐渐增加,其相关系数r0.99,说明在实验浓度范围内,存在极显著的浓度-效应关系。洛克沙胂对秀丽隐杆线虫胚胎细胞DNA具有损伤作用,彗星实验操作简便、快速、灵敏度高,能够反映出洛克沙胂的遗传毒性。因此,通过彗星实验建立实验室检测洛克沙胂遗传毒性的方法具有可行性。     

The combined effects of biomass and temperature on maximum specific ammonia oxidation rate in domestic wastewater treatment

• Actual SAORs was determined using MLVSS and temperature. • Measured SAOR decreased with increasing MLVSS 1.1‒8.7 g/L. • Temperature coefficient (θ) decreased with increasing MLVSS. • Nitrification process was dynamically simulated based on laboratory-scale SBR tests. • A modified model was successfully validated in pilot-scale SBR systems. Measurement and predicted variations of ammonia oxidation rate (AOR) are critical for the optimization of biological nitrogen removal, however, it is difficult to predict accurate AOR based on current models. In this study, a modified model was developed to predict AOR based on laboratory-scale tests and verified through pilot-scale tests. In biological nitrogen removal reactors, the specific ammonia oxidation rate (SAOR) was affected by both mixed liquor volatile suspended solids (MLVSS) concentration and temperature. When MLVSS increased 1.6, 4.2, and 7.1-fold (1.3‒8.9 g/L, at 20°C), the measured SAOR decreased by 21%, 49%, and 56%, respectively. Thereby, the estimated SAOR was suggested to modify when MLVSS changed through a power equation fitting. In addition, temperature coefficient (θ) was modified based on MLVSS concentration. These results suggested that the prediction of variations ammonia oxidation rate in real wastewater treatment system could be more accurate when considering the effect of MLVSS variations on SAOR.     

覆盖作物及耕作方法对土壤丝状真菌生物量的影响

以日本国立大学法人茨城大学农学部田间科学教育研究中心附属农场为研究对象,在不同季节(2004年5月、10月和2005年5月、10月)对农田采取旋耕、梨耕和免耕处理,并在每一耕作处理区分别种植黑麦(Secale cereale L .)、毛野豌豆(Vicia villosa Roth)和杂草(休闲处理对照区),来研究覆盖作物及耕作方法对土壤中真菌生物量的影响效果.结果表明,在免耕处理区,覆盖黑麦、毛野豌豆和杂草的土壤表层(0～10 cm)中,其真菌的牛物量均分别高于相应覆盖物的深层土壤(10～30 cm)中真菌的生物量,并且覆盖黑麦的土壤表层中真菌的生物量比覆盖毛野豌豆的高很多,在2004年5月和10月测得的土壤表层中,覆盖黑麦的真菌生物量分别是覆盖毛野豌豆的1.2和1.8倍,在2005年5月和10月,分别是1.6和1.2倍.对旋耕和梨耕处理区,在不同深度的土层和覆盖物的条件下,真菌生物量均没有明显变化.从上述结果,不同的耕作方式和覆盖不同的作物都会影响土壤中真菌的生物量,并且,免耕和覆盖黑麦相结合,对土壤表层中的真菌生物量影响最为显著.另外,在不同的土壤层之间,表层中的真菌生物量要高于深层土壤.     

全氟辛烷磺酸暴露对赤子爱胜蚓的急性毒性效应

采用人工土壤培养法,通过14 d急性暴露试验,研究了全氟辛烷磺酸(PFOS)对赤子爱胜蚓(Eisenia fetida)的死亡率、谷胱甘肽硫转移酶(GST)和过氧化氢酶(CAT)活性以及DNA损伤的影响。研究结果表明：PFOS对蚯蚓14 d-LC₅₀为478.0 mg·kg^-1,显示为低毒;急性暴露期间,PFOS显著抑制蚯蚓生长,生长抑制率随着PFOS浓度增加而增大,且有良好的剂量效应关系(r=0.951,P<0.01);PFOS对蚯蚓GST和CAT活性均没有显著性影响,没有观察到剂量效应关系;PFOS可致蚯蚓体腔细胞DNA损伤,不同浓度的PFOS对蚯蚓体腔细胞尾长、尾部DNA含量和尾矩的影响具有一定的剂量效应关系(P<0.01),与对照组之间存在显著性差异(P<0.05)。上述结果表明,PFOS对蚯蚓的存活影响显示为低毒,但是对生长有一定影响,可致蚯蚓体腔细胞DNA损伤。     

The impacts of economic restructuring and technology upgrade on air quality and human health in Beijing-Tianjin-Hebei region in China

Impacts of industrial restructuring and upgrade on air quality & health are assessed. An integrated approach combining different models is used for the assessment. Industrial technology upgrading is more effective than economic restructuring. Ozone is much more difficult to mitigate than PM_2.5. In this study, we have analyzed possible policy options to improve the air quality in an industrialized region—Beijing, Tianjin and Hebei (BTH) in China. A comprehensive model framework integrating GAINS-China, GEOS-Chem, and IMED/HEL is established to investigate the impacts of various policies on air pollution and health effects. The model establishes a data interface between economic input/output data and the emission inventory of atmospheric pollutants in the BTH region. Based on in-depth analyses of pollutant emission standards, industrial structure, pollution-intensive industries, and emission intensities in BTH and Pearl River Delta, several scenarios are constructed to explore the effectiveness of policy pathways in improving air quality in the BTH region. These scenarios include two categories: the category of “Industrial Technology Upgrade Policy” scenarios that focuses on reducing the emission intensity of industries vs. that of “Industrial Structure Adjustment Policy” scenarios that focuses on adjusting the proportion of industrial value-added. Our results show that the policy path of industrial technology upgrading can be effective and feasible, while economic structure adjustment shows complex and mixed effectiveness. We also find that the proposed policies and measures will be efficient to reduce pollution of primary pollutants and fine particles, but may not effectively mitigate ambient ozone pollution. Ozone pollution is projected to become increasingly severe in BTH, placing a challenge to pollution mitigation strategies that requires further adjustments to address it.     

Evaluation of environmental stress by comet assay on freshwater snail Lymnea luteola L. exposed to titanium dioxide nanoparticles

The use of aquatic organisms to monitor for contamination is well-established. Therefore, this study was designed to assess the adverse effects of titanium dioxide nanoparticles (TiO₂NP) in freshwater snail Lymnea luteola L. (L. luteola). For TiO₂NPs ecotoxicity tests, snails were exposed for seven days. A dose and time-response relationship was observed for TiO₂NP-induced genotoxicity. Induction of oxidative stress in digestive gland was observed by a decrease in glutathione and gluthathions-S-transferase levels accompanied by elevated malondialdehyde levels at TiO₂NP (9 and 28 µg/mL). Superoxide dismutase activities were markedly reduced at TiO₂NP (9 and 28 µg/mL) at days 1 and 3, but not at day 7. Catalase activities were decreased at days 1 and 3 but increased at higher concentration of TiO₂NP at day 7. DNA fragmentation occurring in L. luteola due to ecotoxic impact TiO₂NP was further substantiated by alkaline single-cell gel electrophoresis assay and expressed in terms of percent tail DNA and olive tail moment. The results indicate that the interaction of these TiO₂NP with snail influences the toxicity, which is mediated by oxidative stress in a dose- and time-dependent manner. The measurement of DNA integrity in L. luteola thus provides an early warning signal of contamination of the aquatic ecosystem by TiO₂NP. Data suggest the freshwater snail L. luteola is a potential biomonitor organism.     

中国降水量高度效应及全球升温对它的影响

利用中国气象中心160站点的实际观察资料,对中国半个世纪的降水变化进行了系统分析,发现中国的夏季降水量与海拔高度存在着很好的反相关关系;同时,全球升温使得降水量的高度效应增强,主要表现为高海拔降水量海拔效应明显增强,这主要是由全球升温引起环流系统增强所引起的.     

Study on particulate matter air pollution,source origin,and human health risk based of PM10 metal content in Volos City,Greece

Investigations on the fluctuation in PM₁₀ air pollution in Volos, a medium-sized industrialized port city in the Mediterranean, are presented for the 5-year period between 2009 and 2014. The levels detected have been examined in relation to legislatively set limits, sampling year, and day of the week. A PM₁₀ spring sampling campaign has been performed in 2014 and metals and other elements in the PM₁₀ mass have been quantified. Source origin has been attempted for the latter sampling campaign and human health risk has been assessed. Results show compliance with the mean annual value of 40 μg m^?3 of 2008/50/EC for the city; however, exceedances of the daily quality standard of 50 μg m^?3 were frequently recorded. Shifts in PM₁₀ concentrations and in contributing sources have been recorded; nevertheless, longer duration data series are needed for safe deductions. Element measurements have enabled source identification for early summer of 2014, with Earth's crust minerals and anthropogenic sources being the main factors. Cumulative non-carcinogenic risk may exceed the threshold value of 1. Possible involvement of sea salt aerosol and desert dust long-range transport has also been assessed. These results may furnish databases on PM pollution of Greek cities as well as other Mediterranean urban centers with similar characteristics.