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61.
● Perfluorooctanesulfonic acid and perfluorooctanoic acid highest in human milk. ● All other perfluoroalkane substances had median values of zero (101 samples). ● Branched PFOS recommended to be analyzed separately from linear isomer. ● PFOS and PFOA showed differentiated regional and income distribution. ● Human health risk assessment values not yet available at global level. Within the global monitoring plan (GMP) established by article 16 of the Stockholm Convention on Persistent Organic Pollutants, perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane sulfonic acid (PFHxS) are recommended for analysis in core matrices to assess occurrence and changes geographically and with time. In 101 samples consisting of 86 national pools and 15 pools from States in Brazil obtained between 2008 and 2019, PFHxS was detected in 17% of the national pools and none in Brazil. PFOA and PFOS had a detection frequency of 100% and 92%, respectively. Other perfluoroalkane substances (PFAS) had either low detection frequencies and median values of zero (carboxylic acids C4–C11; except PFOA) or could not be quantified in any sample (sulfonic acids, C4–C10, and long-chain carboxylic acids, C12–C14). Correlation between PFOA and PFOS was moderately (r = 0.58). Whereas median values were almost identical (18.9 pg/g f.w. for PFOS; 18.6 pg/g f.w. for PFOA), PFOS showed larger ranges (< 6.2 pg/g f.w.–212 pg/g f.w.) than PFOA (< 6.2 pg/g f.w.–63.4 pg/g f.w.). It was shown that wealthier countries had higher PFOA concentrations than poorer countries. No difference in concentrations was found for samples collected in countries having or not having ratified the Stockholm Convention amendments to list PFOS or PFOA. The goal to achieve 50% decrease in concentrations within ten years was met by Antigua and Barbuda, Kenya, and Nigeria for PFOS and by Antigua and Barbuda for PFOA. In a few cases, increases were observed; one country for PFOS, four countries for PFOA.  相似文献   
62.
基于生物监测法,以北京城区为研究区域,采集了不同功能区和交通水平下的20个采样点的油松松针,采用ICP-AES测定了松针中的w(Pb)、w(Cd)、w(Cu)、w(Zn)、w(S)和w(Ca),对北京城区空气质量空间分布特征及潜在生态风险进行了分析. 结果表明:较高的w(Pb)主要分布在北京西南部的工业区和人口密集居住区;位于老城的交通繁忙区和人口密集居住区及西南部工业区的w(Cu)均较高;较高的w(S)主要出现在北京城西南及东南部的工业区. 因子分析表明:污染物Pb、Zn、Cd和S主要来源于混合污染源(如工业排放、家用炉灶和汽车尾气);Cu主要由人为活动过程(如金属加工)释放. 总的说来,松针中w(Pb)与w(S)高于植物生长的正常范围,对植物生长和人类健康构成了潜在威胁,而Cd、Cu和Zn的污染未呈现潜在生态风险.   相似文献   
63.
Antioxidant enzyme activities of fish (Oreochromis niloticus) were determined in order to assess the status of pollution in the Wadi Namar (WN), near Riyadh, Saudi Arabia. Activities of four antioxidant enzymes as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and concentrations of glutathione (GSH) and oxidant malondialdehyde (MDA) were selected as bioindicators. Fish (n = 14) were sampled in the month of April 2013 from WN and a control site (CS). SOD activity was increased by 37.9%, 47%, and 29% in kidney, liver, and heart, respectively, while a significant decrease (36.4%) was observed in gills of O. niloticus from WN as compared to fish from CS. CAT activity was reduced by 51%, 55%, 47%, and 35% in kidney, liver, heart, and gills of O. niloticus from WN. The GST activities in kidney, liver, and heart of O. niloticus from WN were elevated by 34%, 48%, and 32%, respectively. However, significant fall (49%) in gills of fish was noted from WN compared to fish from CS. GSH levels were increased by 44%, 36%, and 38% in kidney, liver, and heart, respectively, but decreased by 30% in gills. MDA levels of O. niloticus were significantly increased in kidney, liver, and heart in fish from WN. Data indicated that WN is polluted mainly by industrial and urban discharge of liquid waste products.  相似文献   
64.
Whole animal concentrations of Pb, Zn and Cd were measured in herbivorous (1 snail species; 1 dipteran larva species), herbivorous + detritivorous (2 slug species), detritivorous (3 woodlouse species; 3 earthworm species), and carnivorous (1 carabid beetle species; 1 lithobiid centipede species) terrestrial macroinvertebrates collected at a disused Pb/Zn mine site. No evidence was found for an accretion of any metal during transference from herbivores to carnivores; the highest metal concentrations were, in fact, generally found in detritivores. The lack of metal bio-amplification during food chain transference is probably due to the sequestration of metals (notably Pb and Zn) in insoluble inorganic-rich granules within certain target organs and cells.

Earthworms and woodlice, respectively, showed major differences in metal concentrations. These differences between closely related species frequently exceeded differences between unrelated species occupying different trophic levels, and may be attributable to a combination of ill-defined ecological and physiological differences that ensure habitat and resource partitioning.  相似文献   
65.
采用计算机摄像跟踪技术,以正常水体中斑马鱼的行为变化为基础,比较突发性氯化镉和敌敌畏污染胁迫下斑马鱼的个体行为(游动速度、深度、转弯次数和加速度)和鱼群行为(平均距离和分散度)的变化规律.研究结果表明:斑马鱼在两种污染物突发性胁迫下,行为反应快速且敏感,游动行为响应与污染物种类和暴露时间直接相关;两种不同类型的污染胁迫...  相似文献   
66.
PO43-和柠檬酸对稀土元素在小麦体内积累和分异的影响   总被引:1,自引:0,他引:1  
闫军才  梁涛  张自立  丁士明 《环境科学》2005,26(5):169-169-173
基于营养液培养,添加外源稀土和ICP-MS分析技术,研究了无机配体PO43-(Pi)及有机配体柠檬酸(Cit)对小麦器官中稀土元素积累和分异的影响.结果表明,不同Pi水平对小麦根中的稀土总含量(∑REE)影响较小,但显著降低叶中∑REE含量;而不同Cit水平对小麦根、叶中∑REE含量都有明显降低作用.对照植物(无Pi、Cit添加)中,稀土元素在小麦根中具有中稀土(MREE)富集及M-型四重效应分布特征,叶中有重稀土(HREE)富集及W-型四重效应分布特征.不同Pi处理对四重效应无明显作用,但进一步加强HREE在小麦叶片中的富集.添加柠檬酸使对照植物根和叶中的分异有逐渐减弱的趋势,在高浓度处理时(Cit≥150μmol·L-),小麦根和叶中出现轻稀土(LREE)富集.  相似文献   
67.
Sequencing batch reactor (SBR) for enhanced biological phosphorus removal (EBPR) processes was used to investigate the impact of the temperature shock on the competition between phosphorus-accumulating organisms (PAOs) and glycogen accumulating organisms (GAOs) in start-up stage. During the 34 days operation, SBR was set with temperature variation(0–5 d, 22±1°C; 6–13 d, 29±1°C; 14–34 d, 14±1°C). PAOs and GAOs were analyzed by fluorescent in situ hybridization (FISH), and intracellular polyphosphate granules were stained by Neisser-stain. The results showed that the influence of temperature shock on PAOs’ abundance was more serious than that on GAOs in the enriching process. Under sudden and substantially temperature variation, from 22±1°C to 29±1°C and then to 14±1°C, the domination of PAOs was deteriorated. After temperature shock, PAOs’ competitive advantages at low temperature that concluded in other study did not appear in our study. As mesophilic, GAOs (indicated by Alphaproteobacteria and Gammaproteobacteria) were more temperature adaptive and better grew and took the domination at 14±1°C in the end. In the competition process, organisms of tetrad forming organisms (TFOs)-like shape which were considered as typical GAOs, were observed. With the evidence of poly-P granules containing by Neisser-straining and result of FISH, these organisms of TFOs-like shape were better to be assumed as adaption state or a special self-protecting shape of PAOs.  相似文献   
68.
Sodium metabisulfite is used in marine shrimp harvesting to prevent the occurrence of black spots. Shrimps are soaked in a sodium metabisulfite solution in ice, which is disposed of in sewages that run into marine canals, creating an environmental hazard. This study evaluates the toxicity and mutagenicity caused by sodium metabisulfite in sea waters and sediments collected in a shrimp farm in Cajueiro da Praia (Luis Correia), state of Piauí, Brazil, using the Allium cepa assay. Water and sediment samples were collected in the dry and in the rainy seasons, in three sites: upstream the shrimp farm (Site 1), at the point sodium metabisulfite is discharged (Site 2), and 100 m downstream the farm (Site 3). Three sample dilutions were used (50%, 25% and 10%) for all samples. A negative control (well water) and a positive control (copper sulfate 0.0006 mg mL−1) were used in each experiment. At the end of the 72-h exposure period, onion roots were measured and removed. Mutagenicity analysis included the determination of mitotic index, chromosomal aberrations and the detection of micronuclei; analysis of root size and mitotic index were used as an index of toxicity. The A. cepa assay revealed that the water and sediments samples collected in the Piauí coast contaminated with sodium metabisulfite induce toxicity. The results demonstrate that the assay may be used as a regular tool in the analysis of water parameters in shrimp farms in the coast of Piauí state, and in strategies to preserve the region’s marine ecosystem.  相似文献   
69.
This paper reports genotoxicity and toxicity data in water samples collected in Sinos River, an important water course in the hydrographic region of Guaíba Lake, Rio Grande do Sul State, south of Brazil. This river is exposed to intense anthropic influence by numerous shoes, leather, petrochemical, and metallurgy industries. Water samples were collected at two moments (winter 2006 and spring 2006) at five sites of Sinos River and evaluated using in vitro V79 Chinese hamster lung fibroblasts (cytotoxicity, comet assay and micronucleus test) and Allium cepa test (toxicity and micronucleus test). Comet and micronucleus tests revealed that water samples collected exerted cytotoxic, toxic, genotoxic and mutagenic effects. The results showed the toxic action of organic and inorganic agents found in the water samples in all sites of Sinos River, for both data collections. The main causes behind pollution were the domestic and industrial toxic discharges. The V79 and A. cepa tests were proved efficient to detect toxicity and genotoxicity caused by complex mixtures. This study also showed the need for constant monitoring in sites with strong environmental degradation caused by industrial discharges and urban sewages.  相似文献   
70.
Biomagnetic monitoring of industry-derived particulate pollution   总被引:2,自引:0,他引:2  
Clear association exists between ambient PM10 concentrations and adverse health outcomes. However, determination of the strength of associations between exposure and illness is limited by low spatial-resolution of particulate concentration measurements. Conventional fixed monitoring stations provide high temporal-resolution data, but cannot capture fine-scale spatial variations. Here we examine the utility of biomagnetic monitoring for spatial mapping of PM10 concentrations around a major industrial site. We combine leaf magnetic measurements with co-located PM10 measurements to achieve inter-calibration. Comparison of the leaf-calculated and measured PM10 concentrations with PM10 predictions from a widely-used atmospheric dispersion model indicates that modelling of stack emissions alone substantially under-predicts ambient PM10 concentrations in parts of the study area. Some of this discrepancy might be attributable to fugitive emissions from the industrial site. The composition of the magnetic particulates from vehicle and industry-derived sources differ, indicating the potential of magnetic techniques for source attribution.  相似文献   
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