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Occurrence of phthalates in aquatic environment and their removal during wastewater treatment processes: a review 总被引:1,自引:0,他引:1
Khalid Muzamil Gani Vinay Kumar Tyagi Absar Ahmad Kazmi 《Environmental science and pollution research international》2017,24(21):17267-17284
Phthalates are plasticizers and are concerned environmental endocrine-disrupting compounds. Due to their extensive usage in plastic manufacturing and personal care products as well as the potential to leach out from these products, phthalates have been detected in various aquatic environments including drinking water, groundwater, surface water, and wastewater. The primary source of their environmental occurrence is the discharge of phthalate-laden wastewater and sludge. This review focuses on recent knowledge on the occurrence of phthalate in different aquatic environments and their fate in conventional and advanced wastewater treatment processes. This review also summarizes recent advances in biological removal and degradation mechanisms of phthalates, identifies knowledge gaps, and suggests future research directions. 相似文献
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In previous studies, boron compounds were considered to be of comparatively low toxicity in the aquatic environment, with predicted no effect concentration (PNEC) values ranging around 1 mg B/L (expressed as boron equivalent). In the present study, we describe an evaluation of toxicity data for boron available for the aquatic environment by different methods.For substances with rich datasets, it is often possible to perform a species sensitivity distribution (SSD). The typical outcome of an SSD is the Hazardous Concentration 5% (HC5), the concentration at which 95% of all species are protected with a probability of 95%. The data set currently available on the toxic effects of boron compounds to aquatic organisms is comprehensive, but a careful evaluation of these data revealed that chronic data for aquatic insects and plants are missing. In the present study both the standard assessment factor approach as well as the SSD approach were applied. The standard approach led to a PNEC of 0.18 mg B/L (equivalent to 1.03 mg boric acid/L), while the SSD approach resulted in a PNEC of 0.34 mg B/L (equivalent to 1.94 mg boric acid/L). These evaluations indicate that boron compounds could be hazardous to aquatic organisms at concentrations close to the natural environmental background in some European regions. This suggests a possible high sensitivity of some ecosystems for anthropogenic input of boron compounds. Another concern is that the anthropogenic input of boron could lead to toxic effects in organisms adapted to low boron concentration. 相似文献
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采用溶剂热法制备N-K2Ti4O9/g-C3N4/UiO-66三元复合材料,并分别经X射线衍射(XRD)、场发射透射电镜(FETEM)、光致发光光谱(PL)、紫外可见吸收光谱(UV-vis)、X射线光电子价带谱(XPS)等予以表征。通过罗丹明(RhB)可见光催化降解实验研究,结果表明N-K2Ti4O9/g-C3N4/UiO-66三元复合材料的光催化性能明显优于单体N-K2Ti4O9、g-C3N4、UiO-66和N-K2Ti4O9/g-C3N4二元复合材料,三元复合材料协同增强的光催化活性是由于UiO-66对RhB吸附量大、g-C3N4传导电子空穴能力强以及复合促进了光生电荷分离的结果。 相似文献
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Lansoprazole and omeprazole degrade in water leading to sulfides, benzimidazolones and a red complex material. Degradation is accelerated in acid medium and by solar simulator irradiation. Benzimidazoles, dianilines and pyridines have also been identified. 相似文献
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The rate and extent of ?-caprolactam degradation in aquatic systems are dependent on the nutrient availability, indigenous microbial population and activity, chemical concentration, and water temperature. The labeled chemical evolved 14CO2 indicating ring cleavage with between 35 and 80% of the radioactivity evolved as 14CO2 after 21 days in yeast extract-supplemented waters. The percent of caprolactam degraded was indirectly related to the chemical's concentration in the water, suggesting microbial inhibition at high caprolactam concentrations. 相似文献
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-- An environmental assessment of the transformation and transport pathways of hexachlorocyclopentadiene (hex) in simulated aquatic ecosystems is presented. Hydrolytic and photolytic disappearance rate constants in distilled and natural waters and in sediment-water systems are given. Sediments in defined sediment-water systems do not significantly affect the disappearance rate constants, compared to distilled water values, for the hydrolytic and photolytic processes. Water solubility, octanol/water partition coefficient, and vapor pressure for hex are also reported and compared with literature values. Fate and transport assessment using an evaluative model indicates that hex will not likely reach substantial steady-state concentrations in the various compartments of the simulated ecosystems. The results also indicate that photolysis and, to a lesser extent, hydrolysis are the predominant degradation processes; export via the water column is the predominant transport process. 相似文献
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在实验室条件下,以静态、序批的方法研究了厌氧颗粒污泥对废水中Hg2+的吸附特性及环境条件对其吸附能力的影响,并通过红外光谱和能谱对比手段,初步探讨了厌氧颗粒污泥吸附Hg2+的机理。结果表明,厌氧颗粒污泥对Hg2+的吸附过程符合准二级吸附动力学模型,其吸附等温线与Freundlich型拟合得较好(R2=0.9933);pH是影响吸附的重要因素,在pH值为3~8的范围内,吸附量较大,最大为64.64 mg/g,当pH值大于8或小于3时,吸附量逐渐下降;温度对吸附也有一定的影响,但影响程度不明显。红外光谱和能谱分析表明,厌氧颗粒污泥表面功能基团对Hg2+的络合作用是吸附的主要机理,这些基团包括—CH、—CH2 、—CH3、P—H、CO、C—N、PO、SO及C—H,同时在吸附过程中还存在一定的离子交换吸附。 相似文献
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Schmidt CK Fleig M Sacher F Brauch HJ 《Environmental pollution (Barking, Essex : 1987)》2004,131(1):107-124
Aminopolycarboxylic acids, such as ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA), 1,3-propylenediaminetetraacetic acid (1,3-PDTA), beta-alaninediacetic acid (beta-ADA), and methylglycinediacetic acid (MGDA), are used in large quantities in a broad range of industrial applications and domestic products in order to solubilize or inactivate various metal ions by complex formation. Due to the wide field of their application, their high polarity and partly low degradability, these substances reach the aquatic environment at considerable concentrations (in the microg/L-range) and have also been detected in drinking water. This review evaluates and summarizes the results of long-term research projects, monitoring programs, and published papers concerning the pollution of the aquatic environment by aminopolycarboxylates in Germany. Concentrations and loads of aminopolycarboxylates are presented for various types of water including industrial and domestic waste waters, surface waters (rivers and lakes), raw waters, and drinking waters. 相似文献
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Jaffé R 《Environmental pollution (Barking, Essex : 1987)》1991,69(2-3):237-257
The fate of hydrophobic organic pollutants in the aquatic environment is controlled by a variety of physical, chemical and biological processes. Some of the most important are physical transport, chemical and biological transformations, and distribution of these compounds between the various environmental compartments (atmosphere, water, sediments and biota). The major biogeochemical processes that control the fate of hydrophobic organic compounds in the aquatic environment are reviewed. These processes include evaporation, solubilization, interaction with dissolved organic matter, sediment-water partitioning, bioaccumulation and degradation. Physico-chemical parameters used to predict the aquatic fate of such compounds are also discussed. 相似文献
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Traditional single species toxicity tests and multiple component laboratory-scaled microcosm assays were combined to assess the toxicological hazard of diesel oil, a model complex mixture, to a model aquatic environment. The immediate impact of diesel oil dosed on a freshwater community was studied in a model pond microcosm over 14 days: a 7-day dosage and a 7-day recovery period. A multicomponent laboratory microcosm was designed to monitor the biological effects of diesel oil (1.0 mg litre(-1)) on four components: water, sediment (soil + microbiota), plants (aquatic macrophytes and algae), and animals (zooplanktonic and zoobenthic invertebrates). To determine the sensitivity of each part of the community to diesel oil contamination and how this model community recovered when the oil dissipated, limnological, toxicological, and microbiological variables were considered. Our model revealed these significant occurrences during the spill period: first, a community production and respiration perturbation, characterized in the water column by a decrease in dissolved oxygen and redox potential and a concomitant increase in alkalinity and conductivity; second, marked changes in microbiota of sediments that included bacterial heterotrophic dominance and a high heterotrophic index (0.6), increased bacterial productivity, and the marked increases in numbers of saprophytic bacteria (10 x) and bacterial oil degraders (1000 x); and third, column water acutely toxic (100% mortality) to two model taxa: Selenastrum capricornutum and Daphnia magna. Following the simulated clean-up procedure to remove the oil slick, the recovery period of this freshwater microcosm was characterized by a return to control values. This experimental design emphasized monitoring toxicological responses in aquatic microcosm; hence, we proposed the term 'toxicosm' to describe this approach to aquatic toxicological hazard evaluation. The toxicosm as a valuable toxicological tool for screening aquatic contaminants was demonstrated using diesel oil as a model complex mixture. 相似文献
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采用ASBR厌氧氨氧化(ANAMMOX)反应器,考察了不同C/N(NH4+-N)比时厌氧氨氧化与反硝化协同脱氮性能表现,并与无机环境下反应器的脱氮性能相比较。研究结果表明,C/N比决定了ANAMMOX/反硝化耦合反应的发展方向。当C/N4+-N和NO2--N的去除率分别为92%、95%、COD去除率大于96%,实现了氨氮及COD的同时去除;当C/N=1.33时,反硝化反应逐渐占据优势;当C/N>2.96时,反硝化作用成为主导反应,厌氧氨氧化反应受到明显抑制,氨氮去除率下降。采取批次实验方法研究了厌氧氨氧化与反硝化协同反应的动力学特性。用基质抑制动力学Haldane模型拟合不同基质浓度下的厌氧氨氧化活性,得到氨氮最大比增长速率为0.09 kg/(kg·d)(以VSS计),半饱和常数为8.4 mg/L、半抑制常数为1 198.2 mg/L;亚硝态氮最大比增长速率为0.27 kg/(kg·d)(以VSS计),半饱和常数为10.2 mg/L、半抑制常数为300.1 mg/L。采用Monod模型和Haldane模型分别拟合不同COD浓度和亚硝酸盐浓度下的反硝化性能,得到反硝化亚硝态氮最大比增长速率为0.2 kg/(kg VSS·d),半饱和常数为17.4 mg/L、半抑制常数为128.4 mg/L,COD半饱和常数为83.3 mg/L。 相似文献
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A review of personal care products in the aquatic environment: environmental concentrations and toxicity 总被引:6,自引:0,他引:6
Considerable research has been conducted examining occurrence and effects of human use pharmaceuticals in the aquatic environment; however, relatively little research has been conducted examining personal care products although they are found more often and in higher concentrations than pharmaceuticals. Personal care products are continually released into the aquatic environment and are biologically active and persistent. This article examines the acute and chronic toxicity data available for personal care products and highlights areas of concern. Toxicity and environmental data were synergized to develop a preliminary hazard assessment in which only triclosan and triclocarban presented any hazard. However, numerous PCPs including triclosan, paraben preservatives, and UV filters have evidence suggesting endocrine effects in aquatic organisms and thus need to be investigated and incorporated in definitive risk assessments. Additional data pertaining to environmental concentrations of UV filters and parabens, in vivo toxicity data for parabens, and potential for bioaccumulation of PCPs needs to obtained to develop definitive aquatic risk assessments. 相似文献
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Fate and effect of monoalkyl quaternary ammonium surfactants in the aquatic environment 总被引:1,自引:0,他引:1
García MT Ribosa I Guindulain T Sánchez-Leal J Vives-Rego J 《Environmental pollution (Barking, Essex : 1987)》2001,111(1):169-175
The effect of the alkyl chain of quaternary ammonium-based surfactants on their aquatic toxicity and aerobic biodegradability has been studied. Two families of monoalkylquats surfactants were selected: alkyl trimethyl ammonium and alkyl benzyl dimethyl ammonium halides. Acute toxicity tests on Daphnia magna and Photobacterium phosphoreum were carried out and EC50 values in the range of 0.1-1 mg/l were obtained for the two series of cationic surfactants. Although the substitution of a benzyl group for a methyl group increases the toxicity, an incremental difference in toxicity between homologs of different chain length were not observed. Biodegradability of the different homologs was determined not only in standard conditions but also in coastal water, both tests yielding similar results. An increase in the alkyl chain length or the substitution of a benzyl group for a methyl group reduces the biodegradation rate. The degradation of these compounds in coastal waters was associated with an increase in bacterioplankton density, suggesting that the degradation takes place because the compound is used as a growth substrate. 相似文献
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实验发现,铁氧化物或铁的羟基氧化物对As(V)有较好的吸附性能,而锆氧化物或锆水合氧化物则对As(Ⅲ)有优异的吸附选择性,但其使用的pH通常要在〉9的条件下。通过简单的共沉淀法制备了Zr-Fe双组分复合吸附剂,在制备过程中通过优化制备条件如:沉淀剂浓度、金属离子总浓度、金属离子配比、反应温度、反应时间及吸附剂价格等因素,最终合成出了对As(V)和As(Ⅲ)都具有良好吸附能力的吸附剂。这种吸附剂在中性条件下对As(V)和As(Ⅲ)的最大吸附量为62mg/g和118mg/g。 相似文献
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Haloacetic acids (HAAs) are environmental contaminants found in aquatic ecosystems throughout the world as a result of both anthropogenic and natural production. The ecological risk posed by these compounds to organisms in freshwater environments, with a specific focus on aquatic macrophytes, was characterized. The plants evaluated were Lemna gibba, Myriophyllum spicatum and M. sibiricum and the HAAs screened were monochloroacetic acid (MCA), dichloroacetic acid (DCA), trichloroacetic acid (TCA), trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA). Laboratory toxicity data formed the basis of the risk assessment, but field studies were also utilized. The estimated risk was calculated using hazard quotients (HQ), as well as effect measure distributions (EMD) in a modified probabilistic ecological risk assessment. EMDs were used to estimate HAA thresholds of toxicity for use in HQ assessments. This threshold was found to be a more sensitive measure of low toxicity than the no observed effect concentrations (NOEC) or the effective concentration (EC10). Using both deterministic and probabilistic methods, it was found that HAAs do not pose a significant risk to freshwater macrophytes at current environmental concentrations in Canada, Europe or Africa for both single compound and mixture exposures. Still, HAAs are generally found as mixtures and their potential interactions are not fully understood, rendering this phase of the assessment uncertain and justifying further effects characterization. TCA in some environments poses a slight risk to phytoplankton and future concentrations of TFA and CDFA are likely to increase due to their recalcitrant nature, warranting continued environmental surveillance of HAAs. 相似文献