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1.
在细胞遗传损伤和免疫功能综合指标中,观察对苯并(a)芘(BaP)敏感并适用于人群检测的指标。结果显示外周血淋巴细胞姐妹染色单体交换(SCE)率与尿中BaP含量呈正相关;并在BP低于10μg/100M3的接触人群中观察到SCE率增高;血清IgG和补体C3与血中BaP含量呈负相关。以SCE率增高、IgG降低和尿中BaP负荷量增高综合评定BaP污染的有危毒险性有应用前景,饮用中华猕猴桃饮料,有助于SCE率增高的恢复和体内BaP的排出。  相似文献   

2.
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。  相似文献   

3.
利用连续液化采样器(PILS)-超声雾化器-气溶胶化学组分检测仪(ACSM)联用系统,对深圳市冬季PM2.5中水溶性组分进行在线连续观测,获取高时间分辨率的水溶性有机物(WSOM),SO42-,NO3-,NH4+和Cl-浓度信息以及WSOM的质谱结构信息.分析结果表明:PM2.5中水溶性组分的总质量浓度变化范围为4.0~117μg/m3,平均浓度为20.1μg/m3,其中WSOM(25.2%)和SO42-(22.4%)是最主要的贡献组分.ACSM质谱显示WSOM具有氧化态有机气溶胶(OOA)的质谱特征,其氧碳比(O/C)的平均值达到(0.60±0.09),且WSOM与二次无机离子(SO42-+NO3-)和钾(K)有强相关性,与黑碳(BC)的相关性较弱,表明了观测期间WSOM主要来源于二次反应产生的二次有机气溶胶(SOA)和生物质燃烧,与机动车等一次排放没有明显关系.  相似文献   

4.
分析了大弹涂肌肉、腮、脏脏、内脏(不含肝脏)以及卵巢等不同器官的还原型谷胱甘肽含量,并以不这原型谷胱甘肽含量较高的肝脏和 卵巢为研究对象,在实验生态条件下,将大弹涂鱼暴露于0,0.05,0.2和0.5mg/L等不同浓度的苯并(a)芘3d,比较这两个器官中还原型谷胱甘肽含量的变化。结果显示,苯并(a)芘肋迫下,大弹 涂鱼肝脏和卵巢还原型谷胱甘肽含量均显著升高(P≤0.05);表明肝脏和卵巢都是代谢苯并(a)芘的主要器官,还原型谷胱甘肽含量的显著升高表明机体对苯并(a)芘胁迫的适应性反应。  相似文献   

5.
重金属(Hg,As,Pb)污染对蚕豆根尖细胞微核的诱变研究   总被引:1,自引:0,他引:1  
采用蚕豆根尖细胞微核检测技术,分别探讨不同浓度的HgCl2、As2O3、Pb(NO3)2对蚕豆根尖细胞微核率的影响。以蒸馏水处理作为阴性对照实验。结果表明不同浓度的HgCl2可使蚕豆根尖细胞微核率明显上升,说明HgCl2对蚕豆根尖具有明显的毒性效应——诱发突变(微核)。不同浓度As2O3可使蚕豆根尖细胞微核率明显上升。说明三氧化二砷(As2O3)对蚕豆根尖具有明显的毒性效应——诱发突变(微核)。蚕豆根尖微核率在铅离子浓度0—25mg/L范围内,随着硝酸铅处理浓度的升高而升高,说明硝酸铅是一种较强的诱变剂。  相似文献   

6.
含氟取代苯类化合物lgKow和-lg1/EC50的QSPR研究   总被引:1,自引:0,他引:1  
采用Gaussian98程序,在B3LYP/6-311G**和HF/6-311G**2种水平上全优化计算了24个含氟取代苯化合物的分子结构,基于得到的分子结构描述符,分别建立了用于预测含氟取代苯化合物正辛醇冰分配系数(lgKow)和毒性(-lg1/EC50)的模型,预测lgKow的模型包含3个变量(偶极矩(μ),总能量(TE)和热能修正值(Eth)),预测-lg1/EC50的模型包含2个变量(分子中原子最负的电荷(q-)和零点振动能(ZPE))。用交叉验证法对模型的稳定性进行了验证(q分别为0.8480和0.9154),并用t-检验和变异膨胀因子(VIF)对2个模型中各变量的显著性和自相关性进行了检验。预lg1/EC50的模型的预测能力优于溶剂化能参数得出的模型。  相似文献   

7.
在PH约为2.3条件下,锰(VII)与邻苯二酚发生氧化还原作用,致使邻苯二酚的荧光(λex/λem=278nm/318nm)发生猝灭,且体系的荧光猝灭程度与锰(II)的浓度在一定范围呈现良好的线性关系,基于此可建立测定锰(II)的荧光分析方法。本文详细研究了其反应的特性和影响因素,在优化的试验条件下,测定锰浓度的线性范围是2×10-8mol/L-3×10-4mol/L,检出限为2×10-9mol/L。RSD=1.0%,常见离子不干扰测定。该方法稳定性好,简便易行,快速准确,有很好的选择性和很高的灵敏度,成功应用于垃圾渗滤液样品中锰(Ⅱ)的测定,实验结果令人满意。  相似文献   

8.
为了解生物炭对水中Cr(Ⅵ)的吸附效果,本文选用蔬菜废物豆角秸秆为原材料,采用限氧升温法在400℃和700℃温度下制备了两种生物炭。并研究了投加量、初始浓度、pH值、吸附时间、温度等因素对生物炭吸附Cr(Ⅵ)的影响。研究结果表明,2种豆角秸秆生物炭对水中Cr(Ⅵ)均有较好的吸附率,吸附最佳条件略有不同;D400对水中Cr(Ⅵ)的最佳吸附条件为投加量8g/L,初始浓度小于40mg·L^-1,pH值2—3;D700对水中Cr(Ⅵ)的最佳吸附条件为投加量8g/L,初始浓度小于60mg·L^-1,pH值2—4;基本达到吸附平衡的时间均为60min;温度对生物炭吸附Cr(Ⅵ)的影响很小。  相似文献   

9.
苯并(a)芘和芘暴露对梭鱼肝脏超氧化物歧化酶活性的影响   总被引:10,自引:0,他引:10  
在实验生态条件下,浓度范围0.1-0.5ug/L的苯并(a)芘和芘的短期暴露(7d),50ug/L浓度组造成梭鱼肝脏SOD活性先抑制后诱导的效应,5ug/L浓度在7d的暴露中,SOD活性未出现诱导而是抑制。同样在50ug/L浓度下,苯并(a)芘暴露4d后SOD活性出现诱导,而芘在暴露7d后才出现诱导,这间接反映了苯并(a)芘和芘的毒性大小。这些结果说明梭鱼肝脏SOD活性与苯并(a)芘和芘暴露有一定的相关性,可以作为海洋环境多环芳烃污染监测的一种生物标志物。  相似文献   

10.
环境医学     
X 18 9502092苯并(a)花对人血淋巴细胞的细胞遗传学损伤研究/杨业鹏…(北京医科大学卫生毒理学教研室)户环境与健康杂志z本刊编辑部(天津、一1994,11(6)一25()一252环信R一36 以不同浓度苯并(a)花(BaP)对人血淋巴细胞进行体外染毒·运用微核(MN)、染色体畸变(C八)和姊妹染色单体交换〔SCE)试验.综合评价了BoP对人血淋巴细胞的细胞遗传学损伤作用结果表明,经S9代谢活化,BaP可诱发细胞MN率,CA率和SCE率显著增高,并呈现明显浓度一反应关系。_上述三指标的变化相互间呈高级正相关。三项指标中与BaP染毒浓度的对数值呈高度正相关。三项…  相似文献   

11.
Serumandurinemonitoringoffluorideexposedworkersinaluminiumsmeltingfactory¥K.Kono;Y.Yoshisda;M.Watanabe;K.Usuda;H.Nagaie;Y.Tak...  相似文献   

12.
We report on the effects of forest management practices of understory removal and N-fixing species (Cassia alata) addition on soil CO2 fluxes in an Eucalyptus urophylla plantation (EUp), Acacia crassicarpa plantation (ACp), 10-species-mixed plantation (Tp), and 30-species-mixed plantation (THp) using the static chamber method in southern China. Four forest management treatments, including (1) understory removal (UR); (2) C. alata addition (CA); (3) understory removal and replacement with C. alata (UR+CA); and (4) control without any disturbances (CK), were applied in the above four forest plantations with three replications for each treatment. The results showed that soil CO2 fluxes rates remained at a high level during the rainy season (from April to September), followed by a rapid decrease after October reaching a minimum in February. Soil CO2 fluxes were significantly higher (P < 0.01) in EUp (132.6 mg/(m2·hr)) and ACp (139.8 mg/(m2·hr)) than in Tp (94.0 mg/(m2·hr)) and THp (102.9 mg/(m2·hr)). Soil CO2 fluxes in UR and CA were significantly higher (P < 0.01) among the four treatments, with values of 105.7, 120.4, 133.6 and 112.2 mg/(m2·hr) for UR+CA, UR, CA and CK, respectively. Soil CO2 fluxes were positively correlated with soil temperature (P < 0.01), soil moisture (P < 0.01), NO3?-N (P < 0.05), and litterfall (P < 0.01), indicating that all these factors might be important controlling variables for soil CO2 fluxes. This study sheds some light on our understanding of soil CO2 flux dynamics in forest plantations under various management practices.  相似文献   

13.
IntroductionNationalStatisticalOffice ,Thailand (NSO ,2 0 0 0 )reportedthattheneedformetalmanufacturingindustriesandassociatedproductionsectorhasincreasedatanextremelyrapidrate ,especiallyinthecentralpartofThailand .Itisestimatedthattherearemorethan 10 0 …  相似文献   

14.
以珠江三角洲5市(广州、深圳、佛山、惠州和肇庆)生活垃圾为研究对象,分析了55个生活垃圾样品的干基组分及典型重金属(As、Cd、Hg、Cr和Pb)的含量,采用主成分因子分析探论重金属的主要影响因素及可能来源,并结合人体健康风险评价模型,用蒙特卡洛模拟定量评价生活垃圾收运、分类及处理各环节环卫工人的健康风险.结果表明,珠江三角洲5市生活垃圾中As、Cd、Hg、Cr和Pb的浓度分别为(4.49±1.18),(1.95±1.96),(0.41±0.60),(147.28±160.48)和(121.59±199.42) mg/kg;生活垃圾中Hg和Pb可能主要来源于金属制品和镀金材料;Cd和Cr可能主要来源于金属制品、镀金材料、快餐垃圾和包装垃圾;As可能主要来源于生活垃圾中的沙土和草木组分.生活垃圾的收运、分类及处理环节,街道清扫保洁工人、分类收运工人和填埋处理工人的非致癌风险基本不用考虑,但致癌风险很高,致癌风险指数最高可达安全阈值的6倍,主要风险暴露途径为手-口摄入(非食物途径);垃圾焚烧处理工人的非致癌风险和致癌风险均很高,非致癌风险和致癌风险指数最高值分别约为安全阈值的11倍和90倍,主要风险暴露途径为手-口摄入和呼吸吸入;相同暴露环境下,女环卫工人的非致癌风险和致癌风险概率均略高于男环卫工人.因此,生活垃圾收运、分类及处理环节需做好安全防范措施,对重金属人体暴露途径进行阻隔.  相似文献   

15.
Based on the concentration of Malathion used in the field, we evaluated the genotoxic potential of low concentrations of this insecticide on meristematic and F1 cells of Allium cepa and on rat hepatoma tissue culture (HTC cells). In the A. cepa, chromosomal aberrations (CAs), micronuclei (MN), and mitotic index (MI) were evaluated by exposing the cells at 1.5, 0.75, 0.37, and 0.18 mg/mL of Malathion for 24 and 48 hr of exposure and 48 hr of recovery time. The results showed that all concentrations were genotoxic to A. cepa cells. However, the analysis of the MI has showed non-relevant effects. Chromosomal bridges were the CA more frequently induced, indicating the clastogenic action of Malathion. After the recovery period, the higher concentrations continued to induce genotoxic effects, unlike the observed for the lowest concentrations tested. In HTC cells, the genotoxicity of Malathion was evaluated by the MN test and the comet assay by exposing the cells at 0.09, 0.009, and 0.0009 mg/5 mL culture medium, for 24 hr of exposure. In the comet assay, all the concentrations induced genotoxicity in the HTC cells. In the MN test, no significant induction of MN was observed. The genotoxicity induced by the low concentrations of Malathion presented in this work highlights the importance of studying the effects of low concentrations of this pesticide and demonstrates the efficiency of these two test systems for the detection of genetic damage promoted by Malathion.  相似文献   

16.
UASB-MBR组合工艺处理模拟黄连素废水   总被引:1,自引:0,他引:1  
采用升流式厌氧污泥床-膜生物反应器(UASB-MBR)组合工艺处理模拟黄连素废水,模拟废水中有机污染物由葡萄糖和黄连素配制,以葡萄糖作为初级能源物质,通过微生物协同降解作用去除废水中的黄连素.在水力停留时间(HRT)为24 h,进水ρ(CODCr),ρ(NH4+-N)和ρ(黄连素)分别为1 717~4 393,91.8~158.7和64.4~276.8 mg/L,废水中黄连素的ρ(CODCr)贡献率为7.5%~25.0%的条件下,组合工艺可实现ρ(CODCr),ρ(NH4+-N)和ρ(黄连素)的去除率分别为92.5%~95.9%,67.0%~98.9%和99%以上,废水中黄连素主要通过UASB去除,去除率为95.2%~98.9%.在进水CODCr负荷为0.54~1.88 kg/(m3·d),黄连素负荷为0.71~12.42 g/(m3·d)的条件下,MBR可保证出水ρ(CODCr),ρ(黄连素)和ρ(NH4+-N)分别低于50,1.0和2.0 mg/L;随着MBR进水ρ(黄连素)升至3.45~12.42 mg/L,在黄连素的微生物毒性胁迫作用下,MBR中污泥呈由分散态向聚集态的转变.   相似文献   

17.
目的 了解炼铝作业氟的危害状况,为工业性氟病的防治提供依据.方法 对氟作业环境作职业卫生学调查.采用剂量患病率寿命表法对866名电解铝作业工人工业性氟病的发病情况进行流行病学调查,并作相关回归分析.结果 该厂接氟工人工业性氟病的总患病率为1.73%,且患病率随累积接氟量的增加而升高,呈高度正相关(r=0.997,P<0.01).并据所求得回归方程(y=10.34InD-18.21)推算出接氟工人控制患病率时的允许连续工作年限和今后的发病趋势.结论 该厂电解铝车间氟危害较重,应加强卫生防护措施,并建议将车间氟最高容许浓度从目前1 mg/m3降为0.5 mg/m3为宜.  相似文献   

18.
为了解噪声对接噪工人血脂代谢的影响,选择381名噪声作业工人为观察组,328名不接触噪声职工作为对照组,对两组进行血脂水平检测.结果显示,噪声组的总胆固醇(TC)和甘油三酯(TC)明显高于对照组(P<0.001和<0.01);TC、TC的异常检出率也高于对照组(P<0.005和<0.05).两组间同年龄、同性别的血脂含量及血脂异常检出率存在较大差异.接噪工龄增加,TC均值增大(P<0.01).调查表明噪声对作业工人的血脂代谢有不良影响,应将血脂含量测定作为噪声作业工人健康监护的项目之一.  相似文献   

19.
聚氨酯合成革厂空气中挥发性有机物的成分谱   总被引:6,自引:1,他引:5       下载免费PDF全文
采用吸附管采样和二次热解吸-GC-MSD联用技术研究了珠江三角洲地区3个典型聚氨酯(PU)合成革厂不同车间空气中挥发性有机物(VOCs)的含量和成分谱.结果表明,主要检出卤代烃、氯苯类、芳香烃类、酯类、酰胺类和酮类等6类共15种VOCs化合物,其中生产车间VOCs总浓度高达(15.300±0.964)mg/m3,而半成品车间、树脂原料车间和厂边界分别为(12.047±0.977)mg/m3,(1.912±1.281)mg/m3, (1.980±0.522)mg/m3;生产车间和半成品车间的VOCs特征轮廓图谱较相似,特征化合物均为甲苯、乙酸乙酯和2-丁酮;而树脂原料车间的特征化合物为甲苯、苯和苯乙烯.源成分谱研究得出该类污染源排放的VOCs分子标志物为乙酸乙酯,其百分比含量最高,达到36.32%± 16.62%.  相似文献   

20.
The treatment of organics present in the lower reaches of a major river system(the Murray–Darling Basin, Australia) before(March–July 2010), during(December 2010–May 2011) and after(April–December 2012) a major flood period was investigated. The flood period(over 6 months)occurred during an intense La Nia cycle, leading to rapid and high increases in river flows and organic loads in the river water. Dissolved organic carbon(DOC) increased(2–3 times) to high concentrations(up to 16 mg/L) and was found to correlate with river flow rates. The treatability of organics was studied using conventional jar tests with alum and an enhanced coagulation model(mEnCo). Predicted mean alum dose rates(per mg DOC) were higher before(9.1 mg alum/mg DOC) and after(8.5 mg alum/mg DOC) than during the flood event(8.0 mg alum/mg DOC),indicating differences in the character of the organics in raw waters. To assess the character of natural organic matter present in raw and treated waters, high performance size exclusion chromatography with UV and fluorescence detectors were used. During the flood period, high molecular weight UV absorbing compounds(〉2 kDa) were mostly detected in waters collected,but were not evident in waters collected before and afterwards. The relative abundances of humic-like and protein-like compounds during and following the flood period were also investigated and found to be of a higher molecular weight during the flood period. The treatability of the organics was found to vary over the three climate conditions investigated.  相似文献   

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