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1.
苯酚(phenol)被广泛应用于工业生产,在水环境中大量检出,具有皮肤灼伤、抑制中枢神经和肝脏损伤等健康毒性.调查了鄱阳湖水体和水产品中苯酚的暴露浓度,采用商值法和概率风险评估法,基于本土人群暴露参数评估苯酚对鄱阳湖流域成人的健康风险.分析结果表明,水体中苯酚浓度范围为ND~556.26 ng·L-1,水产品中苯酚含量范围在11.98~255.51 μg·kg-1.鄱阳湖湖区成人饮水健康风险值在3.80×10-7~8.46×10-5范围内,湖区南部河流聚集处及北部长江交汇处的成人饮水健康风险较高.成人通过食用鄱阳湖不同种类水产品产生的健康风险范围为2.65×10-5~1.47×10-4,食用黄颡鱼和鲶鱼产生的健康风险比其他种类水产品高一个数量级.通过Monte Carlo模拟评估苯酚的健康概率风险,并探讨鄱阳湖流域人群暴露参数敏感性.结果表明鄱阳湖流域成人饮水和水产品食用的95百分位健康风险值处于可接受水平,苯酚环境暴露浓度对健康风险值的影响最大.本研究结果可为鄱阳湖流域水环境中苯酚的风险管控提供参考.  相似文献   

2.
会仙岩溶湿地水体金属元素分布与健康风险评价   总被引:8,自引:6,他引:2  
李军  邹胜章  梁永平  林永生  周长松  赵一 《环境科学》2020,41(11):4948-4957
以我国最大的低海拔岩溶湿地会仙岩溶湿地为研究区域,对该区域内4种主要类型水(井水、地表河水、地下河水和溶潭水)的23组样品中9种金属元素(As、Cr、Al、Cu、Pb、Zn、Ni、Mn和Hg)进行检测和分析,运用多元统计方法和健康风险评价模型分别研究了9种金属元素在4种类型水中的浓度特征和健康风险.结果显示,会仙岩溶湿地水体中金属元素平均浓度顺序为Al > Mn > Zn > Cr > Ni > As > Hg > Cu > Pb,井水中Hg(1.08 μg ·L-1)、地表河水中Hg(0.78 μg ·L-1)和Mn(259.00 μg ·L-1)以及溶潭水中Hg(0.47 μg ·L-1)和Al(300.00 μg ·L-1)的最大浓度已超过我国相应水质标准,地下河水样中未出现金属元素超标.从水体中金属元素角度,井水和地下河水质总体优于地表河水和溶潭水.井水中Cr、Ni、Cu和Zn浓度主要与地质背景值有关,溶潭水中Al和Pb浓度主要受北部硫铁矿开采和居民活动影响,河流中As和Mn浓度可能受旅游活动、渔业养殖和河道底泥综合影响.健康风险评价结果显示,4种类型水中9种金属元素通过饮用水途径和皮肤入渗途径引起的年均总健康风险顺序为井水 > 地下河水 > 溶潭水 > 地表河水,井水中金属元素通过饮用水途径对成人(6.11×10-5 a-1)和儿童(6.67×10-5 a-1)引起的年均总健康风险值已超过最大可接受风险水平(5.0×10-5 a-1).Cr是引起年均致癌健康风险的主要金属元素.从饮用水安全角度,在饮用前需对井水中的Hg和Cr污染物进行适当控制.  相似文献   

3.
中国居民饮用水镉暴露非致癌风险的年龄分层权重   总被引:2,自引:2,他引:0  
饮水是人体镉(Cd)暴露的重要途径,为了定量表征中国居民饮用水镉暴露风险,通过文献调研收集我国3类主要饮用水类型的镉浓度数据.利用回归模型获得不同年龄段人群饮水暴露参数分布模式.基于概率方法评价不同水体和不同人群由于饮用水镉暴露造成的非致癌风险.结果发现,3种类型水体镉浓度存在显著差异.自来水、未处理的地下水和地表水源...  相似文献   

4.
兰州市大气PM10中重金属和多环芳烃的健康风险评价   总被引:5,自引:0,他引:5  
以现场采样监测和问卷调查方式,结合美国环保局推荐的健康风险评价模型,对兰州市大气PM10中重金属、PAHs及其健康风险进行了研究.结果表明:兰州市大气PM10中重金属和PAHs具有明显的季节特征,冬季高于夏季;人群对重金属和PAHs的日均暴露剂量在9.60×10-5~1.06×10-3 mg·kg-1·d-1之间,儿童的日均暴露剂量高于成人,男性高于女性;Zn和4环及4环以上的PAHs对总暴露剂量的贡献率较高.无论致癌风险还是非致癌风险,研究区均高于对照区,男性高于女性,其中,男性儿童致癌风险最高,预期寿命损失为2.17 d.冬季研究区和对照区的致癌风险均高于美国EPA推荐的可接受风险水平.  相似文献   

5.
亚硝胺是一类具有高致癌性和致突变性的含氮有机污染物. 支流水系作为我国中小城镇的主要饮用水源,其亚硝胺的污染情况尚不明确,关于支流河水中亚硝胺及其前体物质浓度的研究仍十分缺乏. 以水体中常见8种亚硝胺为研究对象,检测了长江一级支流清江河水及氯胺化处理后水样中亚硝胺浓度组成特征,并针对重要的污水排放源进行重点监测,分析亚硝胺及其前体物质的环境影响因素,评估其健康和生态风险. 结果表明,清江河水共检出6种亚硝胺,其中主要亚硝胺为NDMA[(10 ±15)ng·L-1]、NDEA[(9.3 ±9.3)ng·L-1]和NDBA[(14 ±7.8)ng·L-1],氯胺化反应后的水样中有7种亚硝胺检出,主要为NDMA-FP[(46 ±21)ng·L-1]、NDEA-FP[(26 ±8.3)ng·L-1]和NDBA-FP[(22 ±13)ng·L-1];河水中亚硝胺的浓度分布整体呈现为中游高于上游和下游,在有污水排放与支流汇入点的亚硝胺浓度明显高于其他点位;对污水直接排放点的监测发现,携带有亚硝胺及其前体物质的污水输入是河水中亚硝胺的主要来源;此外,3种主控污染物NDMA、NDBA和NDEA的浓度存在一定相关性,主要原因是其存在相似的污水来源;饮用水源地亚硝胺浓度对当地居民存在潜在致癌风险(2.4×10-5);此外,由于清江具有较高的亚硝胺生成潜能,其饮用水致癌风险可能会更高;生态风险评价表明,亚硝胺对于清江流域的生态风险商值低于0.002,生态风险可忽略不计.  相似文献   

6.
村镇中小型饮用水源是中国农村饮用水的主要类型,对该类水源中碘化物分布特征的研究较少.为探明山东、安徽村镇饮用水源中碘化物的分布、来源及存在的饮用健康风险,于2021年10—11月对该区域97个代表性村镇饮用水源(湖库、河流、地下水)进行调研和样品采集,综合水化学分析、统计学和风险评价等方法进行分析.结果表明,研究区水体中碘化物的浓度为0.1~294.5 μg·L-1,其中15%的点位为高碘型 水源,集中在山东菏泽和安徽北部的地下水源,50%的点位为缺碘型水源,以地表水源为主.碘化物浓度与水化学类型密切相关,Ca2+·HCO3-型水源中74%为缺碘型,Na+·HCO3-型水源中45%为高碘型.岩石风化的空间异质性导致水化学类型存在差异,水岩作用下的阳离子交换使沉积岩中的碘释放到水中,蒸发浓缩使水中的碘化物富集.健康风险评价表明,2%的水源(菏泽郓城县、淮北濉溪县)的儿童风险熵大于1,成人的高碘饮用水健康风险较低.  相似文献   

7.
为探究典型工业城市大气PM2.5载带重金属的季节分布、来源及健康风险,于2019~2020年分季节采集PM2.5有效样品112个,利用电感耦合等离子体发射光谱法(ICP-AES)测定了19种元素含量.结果表明,PM2.5及其载带重金属元素的年均浓度分别为(66.25±35.73)μg·m-3和(1.32±0.84)μg·m-3.PM2.5及其元素组分夏季浓度最低,Al、Ca、Fe、Mg和Ti等元素春季浓度最高,其它元素则是冬季浓度最高.利用PMF-PSCF模型共解析出5类排放源,分别为Ni和Co相关排放源(5.8%)、机动车源(13.7%)、Cd相关排放源(5.1%)、燃烧源(18.2%)和扬尘源(57.3%).风险评价结果表明,每一类排放源的危害指数(HI)值均小于1,不存在明显的非致癌风险;致癌风险均处于10-6~10-4范围内,具有一定的致癌风险.与其它排放源相比,燃烧源的致癌风险(8.74×10-6,36.9%)和非致癌风险(0.60,25.6%)最大,建议优先对燃烧源进行治理以降低区域人群暴露风险.  相似文献   

8.
郑州市冬季VOCs污染特征、来源及健康风险评估   总被引:8,自引:0,他引:8  
采用GC5000在线气相色谱仪于2018年1月8—26日对郑州市城区进行大气环境挥发性有机化合物(VOCs)监测,开展污染特征分析、来源解析和苯系物(BTEX)健康风险评估.结果表明,监测期间郑州市城区TVOC平均浓度为64×10-9,污染期时段平均浓度为84×10-9,约是非污染时段的2倍;组分构成显示烷烃占比最大,其次是烯炔烃和芳香烃;源解析结果显示,VOCs主要来源是液化石油气/天然气(25%)、机动车尾气(24%)、燃烧(21%)、工业排放(16%)和溶剂使用(14%);监测期间苯系物非致癌风险危害值(HQ)在美国环保署规定的安全范围内,苯的致癌风险(R)为2.2×10-6,超过了美国环保署规定的安全阈值(1.0×10-6).对成年人存在致癌风险,需要引起关注.  相似文献   

9.
采集银川市城区不同功能区的40个地表灰尘样品,采用气相色谱质谱联用的检测方法,测定了美国环保局(EPA)优先控制的6种PAEs化合物的含量,并对其污染特征、污染分布和人体暴露的健康风险进行了评价.结果表明,6种邻苯二甲酸酯化合物在地表灰尘样品中均被检测出,Σ6PAEs的含量为0.096~24.952 mg·kg-1,平均值和中位数分别为3.452 mg·kg-1和1.905 mg·kg-1.各功能区地表灰尘中Σ6PAEs平均含量由高到低依次为住宅区、文教区、公园、工业区、商业区和交通区.各功能区地表灰尘中的主要PAEs单体为邻苯二甲酸(2-乙基)己酯(DEHP)和邻苯二甲酸二丁酯(DnBP),二者占到Σ6PAEs的97.07%.对人体健康风险评价表明,研究区6种优先控制化合物对人体产生的非致癌风险均小于1,未超过EPA推荐的非致癌水平,邻苯二甲酸丁基苄基酯(BBP)的致癌风险在可接受的标准范围内,有2个样点的DEHP致癌风险超过EPA推荐的致癌水平,应引起一定的重视.  相似文献   

10.
有机磷酸酯(OPEs)作为溴代阻燃剂的替代品,在生产生活中被广泛使用,其环境污染和毒性效应受到广泛关注.梳理中国七大典型流域水体中OPEs的含量水平和分布特征,计算中国成人、青少年和儿童的OPEs日均饮水暴露量,对其健康风险进行评估,并通过蒙特卡洛模拟方法评价了结果的可靠性.检索整理了12种OPEs对水生生物的毒性效应浓度,构建物种敏感度分布(SSD)曲线,对生态风险进行评估.结果表明,低等暴露水平下,七大流域ΣOPEs的第5百分位浓度为52.61 ng·L-1;中等暴露水平下,七大流域ΣOPEs的中位浓度为499.74 ng·L-1,磷酸三氯乙酯(TCEP)、磷酸三乙酯(TEP)和磷酸三(1,3-二氯-2-丙基)酯(TDCP)为主要污染物;高等暴露水平下,七大流域ΣOPEs的第95百分位浓度为1904.4 ng·L-1,是其中等暴露水平的3.8倍,长江流域的ΣOPEs浓度最高.健康风险评估表明,不同人群通过饮用水暴露于OPEs的非致癌风险均在可接受范围内.磷酸三甲酯(TMP)、磷酸三异丁酯(TiBP)和TCEP是致癌风险的主要贡献者.生态风险评估结果表明,TCEP在高等暴露水平下存在中等生态风险;磷酸三正丁酯(TnBP)在中等暴露水平下存在中等生态风险,在高等暴露水平下,有较高生态风险;磷酸三苯酯(TPhP)在低中高3种暴露水平下的风险商均大于1,有较高生态风险,需要重点关注.  相似文献   

11.
Toxic effects of two agrochemicals on nifH gene in agricultural black soil were investigated using denaturing gradient gel electrophoresis (DGGE) and sequencing approaches in a microcosm experiment. Changes of soil nifH gene diversity and composition were examined following the application of acetochlor, methamidophos and their combination. Acetochlor reduced the nifH gene diversity (both in gene richness and diversity index values) and caused changes in the nifH gene composition. The effects of acetochlor on nifH gene were strengthened as the concentration of acetochlor increased. Cluster analysis of DGGE banding patterns showed that nifH gene composition which had been affected by low concentration of acetochlor (50 mg/kg) recovered firstly. Methamidophos reduced nifH gene richness that except at 4 weeks. The medium concentration of methamidophos (150 mg/kg) caused the most apparent changes in nifH gene diversity at the first week while the high concentration of methamidophos (250 mg/kg) produced prominent effects on nifH gene diversity in the following weeks. Cluster analysis showed that minimal changes of nifH gene composition were found at 1 week and maximal changes at 4 weeks. Toxic effects of acetochlor and methamidophos combination on nifH gene were also apparent. Different nifH genes (bands) responded differently to the impact of agrochemicals: four individual bands were eliminated by the application of the agrochemicals, five bands became predominant by the stimulation of the agrochemicals, and four bands showed strong resistance to the influence of the agrochemicals. Fifteen prominent bands were partially sequenced, yielding 15 different nifH sequences, which were used for phylogenetic reconstructions. All sequences were affiliated with the alpha- and beta-proteobacteria, showing higher similarity to eight different diazotrophic genera.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
Several main metabolites of benzo[a]pyrene (BaP) formed by Penicillium chrysogenum, Benzo[a]pyrene-1,6-quinone (BP 1,6- quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (BP 7,8-diol), 3-hydroxybenzo[a]pyrene (3-OHBP), were identified by high-performance liquid chromatography (HPLC). The three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. However, their further degradation was essential for the complete degradation of BaP. To enhance their degradation, two methods, degradation by coupling Penicillium chrysogenum with KMnO4 and degradation only by Penicillium chrysogenum, were compared; Meanwhile, the parameters of degradation in the superior method were optimized. The results showed that (1) the method of coupling Penicillium chrysogenum with KMnO4 was better and was the first method to be used in the degradation of BaP and its metabolites; (2) the metabolite, BP 1,6-quinone was the most liable to be accumulated in pure cultures; (3) the effect of degradation was the best when the concentration of KMnO4 in the cultures was 0.01% (w/v), concentration of the three compounds was 5 mg/L and pH was 6.2. Based on the experimental results, a novel concept with regard to the bioremediation of BaP-contaminated environment was discussed, considering the influence on environmental toxicity of the accumulated metabolites.  相似文献   

14.
Sorption of chlorotoluron in ammonium sulfate, urea and atrazine multi-solutes system was investigated by batch experiments. The results showed application of nitrogen fertilizers to the soil could affect the behavior of chlorotoluron. At the same concentration of N, sorption of chlorotoluron decreased as the concentration of atrazine increased on the day 0 and 6 in soil, respectively. The sorption of chlorotoluron increased from 0 to 6 d when soils were preincubated with deionized water, ammonium sulfate and urea solution for 6 d. That indicated incubation time was one of the most important factors for the sorption of chlorotoluron in nitrogen fertilizers treatments. The individual sorption isotherms of chlorotoluron in rubbery polymer and silica were strictly linear in single solute system, but there were competition sorption between pesticides or between pesticides and nitrogen fertilizers. That indicated the sorption taken place by concurrent solid-phase dissolution mechanism and sorption on the interface of water-organic matter or water-mineral matter.  相似文献   

15.
In this study an effort has been made to use plant polyphenol oxidases; potato (Solanum tuberosum) and brinjal (Solanum melongena), for the treatment of various important dyes used in textile and other industries. The ammonium sulphate fractionated enzyme preparations were used to treat a number of dyes under various experimental conditions. Majority of the treated dyes were maximally decolorized at pH 3.0. Some of the dyes were quickly decolorized whereas others were marginally decolorized. The initial first hour was sufficient for the maximum decolorization of dyes. The rate of decolorization was quite slow on long treatment of dyes. Enhancement in the dye decolorization was noticed on increasing the concentration of enzymes. The complex mixtures of dyes were treated with both preparations of polyphenol oxidases in the buffers of varying pH values. Potato polyphenol oxidase was significantly more effective in decolorizing the dyes to higher extent as compared to the enzyme obtained from brinjal polyphenol oxidase. Decolorization of dyes and their mixtures, followed by the formation of an insoluble precipitate, which could be easily removed simply by centrifugation.  相似文献   

16.
RemovalofheavymetalsfromsewagesludgebylowcostingchemicalmethodandrecyclinginagricultureWuQitang,NyirandegePascasie,MoCehuiF...  相似文献   

17.
A study was conducted to compare the diversity of 2-, 3-, and 4-chlorobenzoate degraders in two pristine soils and one contaminated sewage sludge. These samples contained strikingly different populations of mono-chlorobenzoate degraders. Although fewer cultures were isolated in the uncontaminated soils than contaminated one, the ability of microbial populations to mineralize chlorobenzoate was widespread. The 3- and 4-chlorobenzoate degraders were more diverse than the 2-chlorobenzoate degraders. One of the strains isolated from the sewage sludge was obtained. Based on its phenotype, chemotaxonomic properties and 16S rRNA gene, the organism S-7 was classified as Rhodococcus erythropolis. The strain can grow at temperature from 4 to 37℃. It can utilize several (halo)aromatic compounds. Moreover, strain S-7 can grow and use 3-chlorobenzoate as sole carbon source in a temperatures range of 10-30℃ with stoichiometric release of chloride ions. The psychrotolerant ability was significant for bioremediation in low temperature regions. Catechol and chlorocatechol 1,2-dioxygenase activities were present in cell free extracts of the strain, but no (chloro)catechol 2,3- dioxygenase activities was detected. Spectral conversion assays with extracts from R. erythropolis S-7 showed accumulation of a compound with a similar UV spectrum as chloro-cis,cis-muconate from 3-chlorobenzoate. On the basis of these results, we proposed that S-7 degraded 3-chlorobenzoate through the modified ortho-cleave pathway.  相似文献   

18.
Single and joint effects of pesticides and mercury on soil urease   总被引:3,自引:3,他引:3  
The influence of two pesticides including chlorimuron-ethyl and furadan and mercury (Hg) on urease activity in 4 soils (meadow burozem and phaeozem) was investigated. The soils were exposed to various concentrations of the two pesticides and Hg individually and simultaneously. Results showed that there was a close relationship between urease activity and organic matter content in soil. Chlorimuron-ethyl and furadan could both activate urease in the 4 soils. The maximum increment of urease activity by chlorimuronethyl was up to 14%-18%. There was almost an equal increase (up to 13%-21%) in the urease activity by furadan. On the contrary, Hg markedly inhibited soil urease activity. A logarithmic equation was used to describe the relationship (P〈0.05) between the concentration of Hg and the activity of soil urease in the 4 tested soils. Semi-effect dose (ED50) values by the stress of Hg based on the inhibition of soil urease in the 4 soils were 88, 5.5, 24 and 20 mg/kg, respectively, according to the calculation of the corresponding equations. The interactive effect of chlorimuron-ethyl or furadan with metal Hg on soil urease was mainly synergic at the highest tested concentrations.  相似文献   

19.
A field study was conducted in the Taihu Lake region, China in 2004 to reveal the organochlorine pesticide concentrations in soils after the ban of these substances in the year 1983. Thirteen organochlorine pesticides (OCPs) were analyzed in soils from paddy field, tree land and fallow land. Total organochlorine pesticide residues were higher in agricultural soils than in uncultivated fallow land soils. Among all the pesticides, ΣDDX (DDD, DDE and DDT) had the highest concentration for all the soil samples, ranging from 3.10 ng/g to 166.55 ng/g with a mean value of 57.04 ng/g and followed by ΣHCH, ranging from 0.73 ng/g to 60.97 ng/g with a mean value of 24.06 ng/g. Dieldrin, endrin, HCB and α-endosulfan were also found in soils with less than 15 ng/g. Ratios of p,p'-(DDD DDE)/DDT in soils under three land usages were: paddy field > tree land > fallow land, indicating that land usage inlfuenced the degradation of DDT in soils. Ratios of p,p'-(DDD DDE)/DDT >1, showing aged residues of DDTs in soils of the Taihu Lake region. The results were discussed with data from a former study that showed very low actual concentrations of HCH and DDT in soils in the Taihu Lake region, but according to the chemical half-lives and their concentrations in soils in 1980s, the concentration of DDT in soils seemed to be underestimated. In any case our data show that the ban on the use of HCH and DDT resulted in a tremendous reduction of these pesticide residues in soils, but there are still high amounts of pesticide residues in soils, which need more remediation processes.  相似文献   

20.
Common silver barb,Puntius gonionotus,exposed to the nominal concentration of 0.06 mg/L Cd for 60 d,were assessed for histopathological alterations(gills,liver and kidney),metal accumulation,and metallothionein(MT)mRNA expression.Fish exhibited pathological symptoms such as hypertrophy and hyperplasia of primary and secondary gill lamellae,vacuolization in hepatocytes,and prominent tubular and glomerular damage in the kidney.In addition,kidney accumulated the highest content of cadmium,more than gills and liver.Expression of MT mRNA was increased in both liver and kidney of treated fish.Hepatic MT levels remained high after fish were removed to Cd-free water.In contrast,MT expression in kidney was peaked after 28 d of treatment and drastically dropped when fish were removed to Cd-free water.The high concentrations of Cd in hepatic tissues indicated an accumulation site or permanent damage on this tissue.  相似文献   

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