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81.
This study presents an assessment of the potential impact of geological contamination of the environment on the health of the population in Spišsko-Gemerské rudohorie Mts. (SGR Mts.). The concentration levels of potentially toxic elements (mainly As, Cd, Cu, Hg, Pb, Sb, and Zn) were determined in soils, groundwater, surface water, and stream sediments as well as in the food chain (locally grown vegetables). A medical study included some 30 health indicators for all 98 municipalities of the study area. The As and Sb contents in human fluids and tissues were analyzed in one municipality identified to be at the highest risk. Based on element content, environmental and health risks were calculated for respective municipalities. Out of 98 municipalities 14 were characterized with extremely high environmental risk and 10 were characterized with very high carcinogenic risk from arsenic (groundwater). Extensive statistical analysis of geochemical data (element contents in soils, groundwater, surface water, and stream sediments) and health indicators was performed. Significant correlations between element contents in the geological environment and health indicators, mainly cancer and cardiovascular diseases, were identified. Biological monitoring has confirmed the transfer of elements from the geological environment to human fluids and tissues as well as to the local food chain.  相似文献   
82.
采用体内染毒的方法,以鲤鱼脑乙酰胆碱酯酶(AchE)活力为指标,研究了有机磷农药对硫磷与氯乐果、甲胺磷涕灭威之间的联合毒性效应.结果表明,这些农药之间均产生较强的协同作用,但是两种农药以不同比例加入,其产生的毒性效应有明显差别,涕灭威/对硫磷之间的协同作用要强于同类农药间的作用.  相似文献   
83.
利用两种采样技术监测淮河水中的有毒有机污染物   总被引:10,自引:0,他引:10       下载免费PDF全文
利用固相萃取(SPE)和三油酸酯-半渗透膜采样器(triolein-SPMD)采集并测定了淮河信阳、淮南2个采样点水样中有毒有机污染物浓度.对2种采样方法的比较发现,对于水中多氯联苯、多环芳烃、取代苯3类目标污染物检出种类基本相同,但这些污染物在SPMD样品中浓度的富集倍数明显增加.污染物在triolein-SPMD酯中的高浓度,便污染物的定性和定量更加容易和准确,可以根据triolein-SPMD酯/水分配平衡理论计算目标污染物在水中的平均浓度,其结果与SPE具有可比性.综合triolein-SPMD在经济和操作上的诸多优点,本研究认为triolein-SPMD技术可在我国的优先污染物的监测工作中发挥作用.  相似文献   
84.
区域持久性有机物的健康风险评价方法研究   总被引:15,自引:9,他引:6  
随着城市和工业的发展,工业点源和机动车排放了大量有毒污染物,加剧了城市居民的健康风险.在传统的健康风险评价的基础上,提出了区域持久性有机物的健康风险评价思想,并对研究方法进行了初步探讨.在GIS的环境中,集成了ISCST3(复杂工业源扩散模型)和传统风险评价中的多种风险源累积的风险评价模型,建立起以GIS为基础的RHRA(区域健康风险评价方法).以上海市杨浦区为例,根据当地的气象条件和区域污染源的分布情况,对由该区域固定源和移动源排放的有毒污染物引起的区域人类致癌风险和非致癌风险进行了研究.结果表明:杨浦区的致癌风险值为500~1.0×104,非致癌风险指数为1.32~85.70.模拟得到有毒污染物产生的健康风险等值线图显示,区域中健康风险的大小与道路机动车流量和工业点源的分布高度相关.   相似文献   
85.
急性毒性藻红外测试中敏感藻的确定方法   总被引:1,自引:1,他引:0  
敏感藻是指在急性毒性藻红外测试中对毒物响应的温差大、时间快、种类多、剂量低的特殊藻类.自然藻中是否存在敏感藻以及如何确定,是建立藻红外测试法的关键.为此,开展了敏感藻确定方法的探索性研究.试验用8种藻,重金属、有机毒物、农药各10种进行测试分析,结果表明:短线脆杆藻(Fragilaria brevistriata)对重金属、羊角月牙藻(Selenastrum capricornutum)对有机毒物、纤细裸藻(Euglena gracilis)对除草剂和杀虫剂、水华鱼腥藻(Anabaena flos-aquae)对杀菌剂的平均绝对温差分别为0.21℃、0.27℃、0.19~0.20℃、0.20℃,分别高出各自的总均温差0.07℃、0.15℃、0.07℃、0.08℃;4种藻的平均响应时间1.5~7.0min,较好响应药品的响应率≥80%;发光细菌对部分药品的灵敏度在0.07~50.0mg·L-1,而4种藻对相同药品的灵敏度在0.01~7.0mg·L-1.根据敏感藻定义和试验结果,确定短线脆杆藻、羊角月牙藻、纤细裸藻、水华鱼腥藻分别为重金属、有机毒物、除草剂和杀虫剂、杀菌剂的敏感藻.  相似文献   
86.
Monitoring of ambient PM10 (particulate matter which passes through a size selective impactor inlet with a 50% efficiency cut-off at 10 μm aerodynamic diameter) has been done at residential (Kasba) and industrial (Cossipore) sites of an urban region of Kolkata during November 2003 to November 2004. These sites were selected depending on the dominant anthropogenic activities. Metal constituents of atmospheric PM10 deposited on glass fibre filter paper were estimated using Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES). Chromium (Cr), zinc (Zn), lead (Pb), cadmium (Cd), nickel (Ni), manganese (Mn) and iron (Fe) are the seven toxic trace metals quantified from the measured PM10 concentrations. The 24 h average concentrations of Cr, Zn, Pb, Cd, Ni, Mn and Fe from ninety PM10 particulate samples of Kolkata were found to be 6.9, 506.1, 79.1, 3.3, 7.4, 2.4 and 103.6 ng/m3, respectively. The 24 h average PM10 concentration exceeded national ambient air quality standard (NAAQS) as specified by central pollution control board, India at both residential (Kasba) and industrial (Cossipore) areas with mean concentration of 140.1 and 196.6 μg/m3, respectively. A simultaneous meteorology study was performed to assess the influence of air masses by wind speed, wind direction, rainfall, relative humidity and temperature. The measured toxic trace metals generally showed inverse relationship with wind speed, relative humidity and temperature. Factor analysis, a receptor modeling technique has been used for identification of the possible sources contributing to the PM10. Varimax rotated factor analysis identified four possible sources of measured trace metals comprising solid waste dumping, vehicular traffic with the influence of road dust, road dust and soil dust at residential site (Kasba), while vehicular traffic with the influence of soil dust, road dust, galvanizing and electroplating industry, and tanning industry at industrial site (Cossipore).  相似文献   
87.
苯甲酸类化合物对发光菌的毒性及定量构效   总被引:2,自引:0,他引:2  
测定了9种苯甲酸类化合物在pH=7时对发光菌的急性毒性(15min-EC50)。应用两种理化参数TSA和ELUMO对毒性数据进行了定量构效关系(QSARs)研究,并在此基础上初步探讨了苯甲酸类化合物的毒性机制。结果表明,苯甲酸类化合物对发光菌的毒性随取代基团的种类及取代位置不同而不同;苯甲酸类化合物对发光菌的致毒机制中可能有亲电作用发生,毒性可用TSA和ELUMO来联合描述。  相似文献   
88.
薛秀玲  袁东星 《环境化学》2006,25(3):310-314
在实验室模拟缢蛏的生长环境,研究乐果和三唑磷对缢蛏的毒性效应.以气相色谱法测定缢蛏体内有机磷农药的含量,并通过光镜观察有机磷农药对缢蛏鳃和消化腺显微结构的影响.结果表明:缢蛏体内乐果和三唑磷的含量随着水体中有机磷农药的增加而增加,有很好的剂量-效应关系,但是无线性相关性.乐果和三唑磷对缢蛏鳃显微结构的影响是:鳃丝变短,鳃丝间隔和基底膜结缔组织增生,鳃孔、血管腔堵塞;不同的是:在乐果胁迫下,上皮细胞纤毛脱落严重,而三唑磷胁迫下,上皮细胞纤毛增生.乐果和三唑磷对缢蛏消化腺显微结构的影响主要表现为腺细胞界限模糊,腺泡水肿变形、部分坏死;结缔组织增生,细胞间质疏松,出现许多空泡;有机磷农药的浓度高时消化腺细胞变性、坏死,细胞质囊泡化.  相似文献   
89.
新烟碱类杀虫剂是目前全球市场占有率最高的一类杀虫剂,它们选择性作用于昆虫烟碱型乙酰胆碱受体,以往普遍认为其对非靶标生物毒性较低。然而,越来越多的证据表明,新烟碱类杀虫剂的暴露会对非靶标生物造成负面影响。本文综述了新烟碱类杀虫剂对水生生物、非靶标昆虫、鸟类和哺乳动物等多种非靶标生物的毒性,以及对人类健康的影响。新烟碱类杀虫剂对各类生物均具有急性致死毒性,但不同物种之间半数致死浓度(LC_(50))或半数致死剂量(LD_(50))差别较大,由低至高依次为昆虫(0.01~2.38 mg·L~(-1),3.7~81 ng·bee~(-1))、甲壳动物(0.59~37.75 mg·L~(-1))、鱼类(1.2~241 mg·L~(-1))、鸟类(15~>2 000 mg·kg~(-1))和哺乳动物(82~>5 000 mg·kg~(-1))。新烟碱类杀虫剂对非靶标生物的亚致死毒性表现在降低繁殖力和生长速度、降低活动性、影响神经系统、扰乱代谢平衡、损伤DNA等。总体上看,吡虫啉的毒性最高,呋虫胺和烯啶虫胺的毒性较低。啶虫脒、噻虫啉、噻虫嗪和噻虫胺的毒性大小顺序随物种不同而不同。对于水生生物和非靶标昆虫,噻虫啉和噻虫胺的毒性较高,而对于鸟类和哺乳动物,啶虫脒的毒性较高。最后针对现有研究的不足,提出了今后的研究方向,以期为该类杀虫剂的风险评估和合理施用提供科学依据。  相似文献   
90.
• Eco-friendly IONPs were synthesized through solvothermal method. • IONPs show very high removal efficiency for CeO2 NPs i.e. 688 mg/g. • Removal was >90% in all synthetic and real water samples. • >80% recovery of CeO2 NPs through sonication confirms reusability of IONPs. Increasing applications of metal oxide nanoparticles and their release in the natural environment is a serious concern due to their toxic nature. Therefore, it is essential to have eco-friendly solutions for the remediation of toxic metal oxides in an aqueous environment. In the present study, eco-friendly Iron Oxide Nanoparticles (IONPs) are synthesized using solvothermal technique and successfully characterized using scanning and transmission electron microscopy (SEM and TEM respectively) and powder X-Ray diffraction (PXRD). These IONPs were further utilized for the remediation of toxic metal oxide nanoparticle, i.e., CeO2. Sorption experiments were also performed in complex aqueous solutions and real water samples to check its applicability in the natural environment. Reusability study was performed to show cost-effectiveness. Results show that these 200 nm-sized spherical IONPs, as revealed by SEM and TEM analysis, were magnetite (Fe3O4) and contained short-range crystallinity as confirmed from XRD spectra. Sorption experiments show that the composite follows the pseudo-second-order kinetic model. Further R2>0.99 for Langmuir sorption isotherm suggests chemisorption as probable removal mechanism with monolayer sorption of CeO2 NPs on IONP. More than 80% recovery of adsorbed CeO2 NPs through ultrasonication and magnetic separation of reaction precipitate confirms reusability of IONPs. Obtained removal % of CeO2 in various synthetic and real water samples was>90% signifying that IONPs are candidate adsorbent for the removal and recovery of toxic metal oxide nanoparticles from contaminated environmental water samples.  相似文献   
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