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931.
The current state of concentrations of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in China is presented. While products that are known to degrade to either PFOS or PFOA have been used in China, concentrations in environmental media have been reported to be relatively low across China. Greater concentrations of PFOS and PFOA were observed in southern and eastern China than in other areas of China. Concentrations of PFOS and PFOA were relatively great in the Huangpu River, with concentrations of 20.5 ng l?1 and 1590 ng l?1, respectively. Surface waters of Dongguan and Shanghai were more contaminated by PFOS and PFOA than that of other cities. Dongguan was the only city in China in which PFOS value in surface water exceeded the water quality criterion, while PFOA concentration in Shanghai was 152 ng l?1. Similar to other contaminants, point-source pollution was also the common pattern of PFOS and PFOA contamination. Concentrations of PFOS in human blood in China were relatively greater in China than other countries, with drinking water contamination given as the most likely source. Concentrations of PFOS in human blood have increased from the 1980s to the 2000s, while such a trend was not observed for PFOA. 相似文献
932.
Spatio-temporal variations in water quality of Nullah Aik-tributary of the river Chenab, Pakistan 总被引:4,自引:0,他引:4
This study reports the spatio-temporal changes in water quality of Nullah Aik, tributary of the Chenab River, Pakistan. Stream
water samples were collected at seven sampling sites on seasonal basis from September 2004 to April 2006 and were analyzed
for 24 water quality parameters. Most significant parameters which contributed in spatio-temporal variations were assessed
by statistical techniques such as Hierarchical Agglomerative Cluster Analysis (HACA), Factor Analysis/Principal Components
Analysis (FA/PCA), and Discriminant Function Analysis (DFA). HACA identified three different classes of sites: Relatively
Unimpaired, Impaired and Less Impaired Regions on the basis of similarity among different physicochemical characteristics
and pollutant level between the sampling sites. DFA produced the best results for identification of main variables for temporal
and spatial analysis and separated eight parameters (DO, hardness, sulphides, K, Fe, Pb, Cr and Zn) that accounted 89.7% of
total variations of spatial analysis. Temporal analysis using DFA separated six parameters (E.C., TDS, salinity, hardness,
chlorides and Pb) that showed more than 84.6% of total temporal variation. FA/PCA identified six significant factors (sources)
which were responsible for major variations in water quality dataset of Nullah Aik. The results signify that parameters identified
by statistical analyses were responsible for water quality change and suggest the possibility of industrial, municipal and
agricultural runoff, parent rock material contamination. The results suggest dire need for proper management measures to restore
the water quality of this tributary for a healthy and promising aquatic ecosystem and also highlights its importance for objective
ecological policy and decision making process. 相似文献
933.
Shahid Mahboob H.F. Alkkahem Al-Balwai F. Al-Misned K.A. Al-Ghanim Z. Ahmad 《毒物与环境化学》2013,95(5):783-798
Concentrations of nine heavy metals (Cr, Cd, Pb, Ni, Cu, Zn, Mn, As, and Fe) in the muscles of four fish species (O. niloticus, C. gariepinus, P. latipinna, and A. d. dispar) collected from the Riyadh River were detected using atomic absorption spectrophotometry in two different seasons in 2012. The concentrations of the studied heavy metals except Cd, Pb, Ni, and Cu in Aphanius d. dispar and Poecilia latipinna were found to be below the safe limits suggested by various authorities. This study also showed that Zn was predominant, while Cr was least accumulated metal in the studied fish muscles. Data demonstrated that there was a significant variation in the heavy-metal concentrations in different fish species in the Riyadh River. Significant positive correlations between heavy-metal concentrations in fish muscles were also found both in pre- and post-monsoon seasons. Metal pollution index was calculated to distinguish polluted from unpolluted ecosystems based upon current knowledge of metal bioavailability, bioconcentration, and bioaccumulation patterns. From the human health point of view, this study showed that there was a possible health risk to consumers due to the intake of Aphanius d. dispar and Poecilia latipinna under the current consumption rate in the country. 相似文献
934.
Lijin Lin Jun Shi Qihua Liu Ming’an Liao Luoyin Mei 《Environmental monitoring and assessment》2014,186(7):4051-4056
In a preliminary study, we found that the cadmium (Cd) concentrations in shoots of the winter farmland weeds Cardamine hirsuta Linn. and Gnaphalium affine D. Don exceeded the critical value of a Cd-hyperaccumulator (100 mg kg?1), indicating that these two farmland weeds might be Cd-hyperaccumulators. In this study, we grew these species in soil containing various concentrations of Cd to further evaluate their Cd accumulation characteristics. The biomasses of C. hirsuta and G. affine decreased with increasing Cd concentrations in the soil, while the root/shoot ratio and the Cd concentrations in shoot tissues increased. The Cd concentrations in shoots of C. hirsuta and G. affine reached 121.96 and 143.91 mg kg?1, respectively, at the soil Cd concentration of 50 mg kg?1. Both of these concentrations exceeded the critical value of a Cd-hyperaccumulator (100 mg kg?1). The shoot bioconcentration factors of C. hirsuta and G. affine were greater than 1. The translocation factor of C. hirsuta was less than 1 and that of G. affine was greater than 1. These findings indicated that C. hirsuta is a Cd-accumulator and G. affine is Cd-hyperaccumulator. Both plants are distributed widely in the field, and they could be used to remediate Cd-contaminated farmland soil in winter. 相似文献
935.
N. Cardellicchio A. Buccolieri A.D. Leo V. Librando Z. Minniti L. Spada 《毒物与环境化学》2013,95(7):1273-1290
The concentrations of Hg, Cd, Pb, Cu, Ni, V, and Sn were determined in marine sediments collected from Taranto Gulf (Ionian Sea, Southern Italy). The aim of this article is to study the methodological approach in order to evaluate total metal levels determined in marine sediments of a contaminated area (Taranto Gulf, Southern Italy), to identify contaminated areas and to predict adverse biological effects based on Sediment Quality Guidelines (SQGs). The results are discussed in relation to geological characteristics of sediments in order to define background levels and anthropogenic input. Experimental results were elaborated by multivariate statistical techniques and Geographical Information System (GIS) software. The geoaccumulation index I geo and two sets of SQGs (in particular (a) the threshold effect level (TEL), the probable effect level (PEL) and (b) the effect range-low (ERL) and the effect range median (ERM)) have been used for environmental evaluation of metal concentrations. Results show that in Taranto coastal area, Mar Piccolo basin represents the most contaminated area. A comparison with results from other Mediterranean areas demonstrates that for some metals (such as Cd, Pb, and Hg) Taranto seas represent one of the most polluted areas in the Mediterranean Sea. A comparison of metal levels with SQGs also suggests an ecotoxicological risk for benthic organisms mainly in the first inlet of Mar Piccolo. 相似文献
936.
Infantile polycystic kidney disease (IPKD) is an autosornal recesive inherited disorder, IPKD has been previously diagnosed by us as early as the 14th week of gestation. ‘Late onset’ (third trimester) IPKD has been previously described by several authors. We present here a case of intrauterine detection of ‘late onset’ IPKD, suggesting that elongated hyperechogenic kidneys (with normal transverse and anteroposterior diameters) should be considered as an early sign of ‘late onset’ presenting IPKD. 相似文献
937.
938.
939.
940.
泥浆体系中受喹啉污染土壤的生物修复 总被引:6,自引:0,他引:6
将受喹啉污染的土壤 (污染量为 1mg/g土)与一定量的水混合形成泥浆 ,通过引入专性喹啉降解菌皮氏伯克霍尔德氏菌(Burkholderia pickettii)进行土壤的生物修复 .结果表明 ,采用引入喹啉降解菌的生物强化技术进行受喹啉污染的土壤的生物修复是可行的 .喹啉降解菌的引入大大加快了喹啉的生物降解过程 .最快只需 6h就可将喹啉完全去除 .考察比较了投菌量 ,泥浆中的含水量及营养元素(N,P)的存在对生物修复效果的影响 .土壤对难降解有机物喹啉的吸附等温线符合弗兰德里希方程 . 相似文献