No difference in activity of Sod-1 genotypes of Poa annua to short-term treatment of ambient gaseous organic pollution

Our previous studies indicated that genotypes at locus Sod-1 of Poa annua changed clinally along a gradient of gaseous organic pollution. In the present study, we aimed to know whether there were differential responses of activities of different superoxide dismutase （SOD） genotypes to short-term treatment of ambient gaseous organic pollution. Significant bias from Hardy-Weinberg equibrium was observed on locus Sod-1, and no genotype Sod- l-BB was found. Significantly increased activities were observed in most treatments for genotype Sod-1-AA and in one treatment for genotype Sod-1-AB. However, no significant difference in SOD activities was found between the two genotypes. It was interpreted that fitness difference between the two genotypes was small and treatment duration was too short or extent of ambient organic pollution was too low to lead to differential responses. Other environmental factor effects on activities of superoxide dismutases can also explain the results.

Hydrodynamic Cavitation Enhanced SR-Aops Degradation of Organic Pollutants in Water:A Review

SR-AOP(sulfate radical advanced oxidation process)is a novel water treatment method able to eliminate refractory organic pollutants.Hydrodynamic cavitation(HC)is a novel green technology,that can effectively produce strong oxidizing sulfate radicals.This paper presents a comprehensive review of the research advancements in these fields and a critical discussion of the principal factors influencing HC-enhanced SR-AOP and the mechanisms of synergistic degradation.Furthermore,some insights into the industrial application of HC/PS are also provided.Current research shows that this technology is feasible at the laboratory stage,but its application on larger scales requires further understanding and exploration.In this review,some attention is also paid to the design of the hydrodynamic cavitation reactor and the related operating parameters.

Level of Bacteriological and Physicochemical Pollution of Surface Waters in Rural Area: The Case of Mbankomo Municipality (Center Region, Cameroon)

A study aimed at evaluating the physicochemical and bacteriological quality of surface water was therefore carried out in a few watercourses in the municipality of Mbankomo, located in the Center Region (Cameroon). The physico-chemical parameters were measured according to the standard method. The organic pollution index (OPI) was determined from the contents of nitrates, phosphates, and ammoniacal nitrogen to characterize the level of organic pollution of the water. The microorganisms sought were total flora, indicators of faecal contamination like total coliforms, faecal coliforms, feacal streptococci and Escherichia coli, as well as the species Clostridium perfringens. The organic pollution index indicates a high-level organic pollution level during the small rainy season and high to moderate during the small dry season. High concentrations of the total and fecal coliforms, streptococci fecal, Escherichia coli and Clostridium perfringens respectively of 1712 × 105 CFU/100mL;82 × 105 CFU/100mL;10 × 105 CFU/100mL;27 × 105 and 40 × 103 CFU/100mL, all higher than WHO standards, indicate that the waterways of Mbankomo are subject to feacal pollution and harbor pathogenic microflora. The cell densities of main bacteria were significantly correlated with main abiotic parameters, such as Escherichia coli, which was significantly correlated with the pH of the water (r = 0.35;p < 0.05). The variation of organic pollution index category means correspond to a high level of organic pollution during the small rainy season and a high to moderate level during the small dry season. The deterioration of the quality of these waters is favored by their proximity to sources of pollution (toilets, plantation), the runoff of the waters contaminated, the use of detergents and wrong maintenance. These waters without any treatment are not recommendable for human consumption according to standards of the World Health Organization.

Synergistic effect of CuO coupled with MoS_(2) for enhanced photodegradation of organic dyes under visible light

A series of MoS_(2)-modified CuO(CuO/MoS_(2))heterostructures were successfully fabricated.The photodegradation properties of organic dyes were explored in detail under visible light.The photocatalytic results demonstrate that the CuO/MoS_(2)-3 heterostructure delivers superior degradation rates towards methyl violet dye(MV)and rhodamine B(RhB),reaching 99.8%and 95.3%within 30 min,respectively.The decent photodegradation activity is due to improved visible light adsorption and faster transfer of electron-hole pairs.The radical trapping experiments show that superoxide radicals(O_(2)^(-))and holes(h+)are the main active species in the removal of MV.Furthermore,the CuO/MoS_(2)-3 composite possesses the prominent stability and recyclability.This work offers a highly sustainable technique for designing a high-efficiency photocatalyst to remove environmental pollutants.

A Review of Metal–Organic Framework-Based Compounds for Environmental Applications

Metal–organic framework-based compounds have recently gained great attention because of their unique porous structure,ordered porosity,and high specific surface area.Benefiting from these superior properties,metal–organic framework-based compounds have been proven to be one of the most potential candidates for environmental governance and remediation.In this review,the different types of metal–organic framework-based compounds are first summarized.Further,the various environmental applications of metal–organic framework-based compounds including organic pollutant removal,toxic and hazardous gas capture,heavy metal ion detection,gas separation,water harvesting,air purification,and carbon dioxide reduction reactions are discussed in detail.In the end,the opportunities and challenges for the future development of metal–organic framework-based compounds for environmental applications are highlighted.

Study on the characteristics and causes of carbon tetrachloride pollution of karst water in eastern suburbs of Jinan

By comparing the testing data of the hydrochemistry components and organic pollution of karst water sample in Jinan with large amount of historical data, the author finds the long-existing problem of carbon tetrachloride pollution and the great change of hydrochemical characteristics of karst water in eastern suburbs of Jinan. Since karst water is the main water-supply source in eastern suburbs of Jinan, these problems have greatly affected the safety of water supply. Based on the analysis of hydrogeological condition in eastern suburbs of Jinan, this thesis discusses the causes of carbon tetrachloride pollution and hydrochemical variation with hydrogeochemical theories so as to protect the precious karst groundwater and Jinan spring water. It is found that through research and analysis that there are mainly two causes of carbon tetrachloride pollution and hydrochemical variation: the vulnerability of karst water in this area; the other being the serious pollution in this area caused by remaining pollution sources of the last century.

Pollution of bed sediments and its changing process of Nansihu Lake

In order to research the changing process of the pollution from the formation of Nansihu Lake, this study determined the isotope age and depositional rate and analyzed the organic geo-chemical quotas and heavy metal quotas of two sedimentary profiles of Weishan and Dushan lakes. Research results showed that from the formation of Nansihu Lake, the change of the pollution could be divided into four phrases. At the early phrase of the formation, the organic matters of the lake mainly derived from the exotic matters and had a close relation to the effect on the water and sands from the Huanghe (Yellow) River. At the middle and late phrases of the development, the endogenous matters of the lake became the main and stable source of the organic matters. The overflow of the Huanghe River, the excavation of the Grand Canal and the cut of trees caused the changes of the historic pollution. In recent 20 years, the modern industrial pollution from the organic matters and heavy metals has an increasingly heavy tendency.

Migration of Biodegradable Organic Matter in Underlying Soils of Household Waste Dumpsites: A Case Study in Abomey-Calavi, Benin

This paper presented the first part of the studies about the development of a tool for groundwater contamination prediction, conducted by the Laboratory of Sciences and Technology of Water (UAC/Benin). The investigation made consisted in estimating the combined effect of retardation factor and biodegradation on migration processes of leachate, in the underlying soils of household waste dumpsites, without active safety barrier. Leachate infiltration tests for different initial conditions were made on soil columns and the breakthrough curves were traced for electrical conductivity, the 5 day biochemical oxygen demand (BOD5) and total kjeldahl nitrogen TKN. A mathematical migration model was developed and solved numerically by finite difference method and implemented with Matlab R2013a. Thus, the calibration of the model was made with electric conductivity data by determining the dispersion coefficient of the studied soils (D = 0.96 cm2/min). Simulations for model verification showed that the established model can perfectly predict the migration of biodegradable organic pollution (BOD5) but did not give conclusive results for the monitoring of nitrogenous organic matter (TKN). The influence of the retardation factor on the migration of biodegradable organic pollutants in soils was linear, while the biodegradation rate of the organic material on migration showed an exponential pattern.

Phytoremediation and its models for organic contaminated soils

Soil pollution has been attracting considerable public attentions over the last decades. Sorts of traditional physiochemical methods have been used to remove the organic pollutants from soils. However, the enormous costs and low efficiencies associated with these remediation technologies limit their availabilities. Phytoremediation is an emerging technology that uses plants to cleanup pollutants in soils. As overwhelmingly positive results have been shown, phytoremediation is a most economical and effective remediation technique for organic contaminated soils. In this paper phytoremediation and its models for organic contaminated soils are viewed. The mechanisms of phytoremediation mainly include the direct plant uptake of organic pollutants, degradation by plant-derived degradative enzymes, and stimulated biodegradation in plant rhizosphere. Phytoremediation efficiency is close related to physicochemical properties of organic pollutants, environmental characteristics, and plant types. It is no doubt that soil amendments such as surfactants improve the solubilities and availabilities of organic pollutants in soils. However, little information is available about effects of soil amendments on phytoremediation efficiencies. Phytoremediation models have been developed to simulate and predict the environmental behavior of organic pollutants, and progress of models is illustrated. In many ways phytoremediation is still in its initial stage, and recommendations for the future research on phytoremediation are presented.

Genotoxicity evaluation and a primary risk assessment of organic pollutants in the drinking water sources of Nanjing, China

An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In this study, the comet assay was conducted to investigate the genotoxicity to human body caused by organic concentrates in the drinking water sources of Nanjing City from Yangtze River of China, and health and ecology risk due to expose to these organic pollutants were evaluated with the multimedia environmental assessment system （MEAS）. For all the water samples, they were collected from four different locations in the drinking water sourcr samples, es of Nanjing City. The results of the comet assay showed that all the organic concentrates from the water samples could induce different levels DNA damages on human peripheral blood lymphocytes, and a statistically significant difference （p〈0.01） was observed compared with the solvent control, which demonstrated the genotoxicity was in existence. According to the ambient severity （AS） of individual compound, we had sorted out the main organic pollutants in the drinking water source of the four waterworks, and the results showed that there was some potential hazard to human body for all the source water, namely the total ambient severity （TAS） of health for each water source was more than 1. However, the TAS of ecology for each water source was less than 1, which indicated that it was safe to ecology. The results of this investigation demonstrate the application of the comet assay and the MEAS in aquatic environmental monitoring studies, and the comet assay found to be fast, sensitive, and suitable for genotoxicity monitoring programs of drinking water source.

Removal of Nitrogen, Phosphorus, and Organic Pollutants From Water Using Seeding Type Immobilized Microorganisms

Objective To study the possibility of removing nitrogen, phosphorus, and organic pollutants using seeding type immobilized microorganisms. Methods Lakes P and M in Wuhan were chosen as the objects to study the removal of nitrogen, phosphorus, and organic pollutants with the seeding type immobilized microorganisms. Correlations between the quantity of heterotrophic bacteria and the total nitrogen （TN）, total phosphorus （TP）, and total organic carbon （TOC） in the two lakes were studied. The dominant bacteria were detected, inoculated to the sludge and acclimated by increasing nitrogen, phosphorus and decreasing carbon source in an intermittent, time-controlled and fixed-quantity way. The bacteria were then used to prepare the seeding type immobilized microorganisms, selecting diatomite as the adsorbent cartier. The ability and influence factors of removing nitrogen, phosphorus, and organic pollutant from water samples by the seeding type immobilized microorganisms were studied. Results The coefficients of the heterotrophic bacterial quantity correlated with TOC, TP, and TN were 0.9143, 0.8229, 0.7954 in Lake P and 0.9168, 0.7187, 0.6022 in Lake M. Ten strains of dominant heterotrophic bacteria belonging to Pseudomonas, Coccus, Aeromonas, Bacillus, and Enterobateriaceae, separately, were isolated. The appropriate conditions for the seeding type immobilized microorgansims in purifying the water sample were exposure time=24 h, pH=7.0-8.0, and quantity of the immobilized microorganisms=0.75-1g/50 mL. The removal rates of TOC, TP, and TN under the above conditions were 80.2%, 81.6%, and 86.8%, respectively. Conclusion The amount of heterotrophic bacteria in the two lakes was correlated with TOC, TP, and TN. These bacteria could be acclimatized and prepared for the immobilized microorganisms which could effectively remove nitrogen, phosphorus, and mixed organic pollutants in the water sample.

Uptake and translocation of organic pollutants in plants:A review

Organic pollutants, such as polychlorinated dJbenzo-p-dioxins and polychlofinated dibenzofurans （PCDD/Fs）, polychlodnated biphenyls （PCBs）, antibiotics, herbicides, and bisphenol A （BPA）, are commonly found in agricultural environments. They are released into the environment as a result of their use for human health purposes and farm management activities, and are often discharged as waste-water effluents. Most of these organic pollutants are taken up by plants through roots and leaves, and when they enter the tissue, they cause serious damage to the plants. Although the toxicity of organic pollutants to plants, especially to plant cells, has been intensively studied, a systematic review of these studies is lacking. Here we review researches on the toxicity of organic pollutants, their uptake, and translocation in plants. Our objective is to assemble existing knowledge concerning the interaction of organic pollutants with plants, which should be useful for the development of plant-based systems for removing pollutants from aquatic and agricultural environments.

Organobentonites as adsorbents for some organic pollutants and its application in wastewater treatment

Two organobentonites were synthesized by placing quaternary ammonium cationscetyltrimethylammonium bromide (CTMAB) and cetylpyridinium chloride (CPC) on bentonite bycation exchange. Their ability to adsorb phenol, aniline. nitrobenzene and p-nitrophenol were examined.The optimal conditions for organobentonites to remove the organic pollutants from waterwere studied. The removal rates for organobentonites to treat the organic compounds in water werefound to be over 8 times for the original mineral (untreated bentonite).The removal rates of organic pollutants and COD of wastewater were further improved by organobentonites in the presence of aluminum sulfate. The structure of organobentonites and the mechanism for their adsorption were investigated by X-ray diffraction (XRD) analysis, infrared spectra and BET surface area.

Modified g-C_(3)N_(4) derived from ionic liquid and urea for promoting visible-light photodegradation of organic pollutants

In this work,modified g-C_(3)N_(4) was fabricated successfully by calcination of ionic liquid(IL) and urea.The addition of IL changed the polymerization mode of urea,induced the self-assembly of urea molecules,modified the morphological structure of the tightly packed g-C_(3)N_(4),and extended the electron conjugation system.When using 1-butyl-3-methylimidazolium chloride([Bmim]Cl) as a modifier,the heteroatom Cl could be inserted into the g-C_(3)N_(4) to optimize the electronic structure.The results of characterizations indicate that the unique structure of modified g-C_(3)N_(4) has an expanded electron delocalization range,introduces an interlayer charge transmission channel,promotes the charge transmission,reduces the band gap,enhances the absorption of visible light,and inhibits electron-hole recombination.Modified g-C_(3)N_(4) showed excellent photocatalytic performance for the degradation of rhodamine B and tetracycline.Furthermore,the effect of different anions in 1-butyl-3-methylimidazolium salts([Bmim]Cl,[Bmim]Br,[Bmim][BF_(4)],and [Bmim][PF_6]) on the structure and function of g-C_(3) N_(4) are discussed.

Persistent organic pollutants control strategy in China

The development of Persistent Organic Pollutants(POPs) control policy in China in the context of international concerns on POPs was reviewed. The aspects of the Chinese POPs control strategies were analyzed, and compared with those of developed counterparts (e.g. US, EU, Japan). Currently, while the legal framework on POPs management, which complies with international guidelines has been established, it should be improved in the areas of special POPs management, risk assessment, the precautionary principle, life-cycle management and technical support capacity. The analysis of Chinese POPs policy and suggestions for strengthening the science-based decision making capacity are not only useful for Chinese decision-makers, but also a case study for developing world and make a great contribution for the global elimination of POPs to make a toxic-free future.

Side－effects of organic and inorganic pollutants on soil nitrification and respiration

Side-effects of heavy metals(Cd and Zn)and organic pollutants(phenanthrene and paclobutrazol)on nitrification and respiration in a loam soil were investigated with its air-dried and fresh conditions. Critical levels for these test pollutants were derived from this investigation.Bioavailable concentrations of Cd and Zn were also determined. It was concluded that such critical levels as NOEL and LOEL of heavy metals should be expressed using bioavailable concentrations rather than total ones since different soil has different properties,especially different absorption ability to heavy metals.

Determining organic compounds in coking wastewater by SPME-GC /MS

The solid-phase microextraction （SPME） combined with gas chromatography/mass spectrometry （GC/MS） was used to determine and analyze organic pollutants in coking wastewater. Based on the fact that the main compounds in the wastewater were organics, some key parameters of the SPME were optimized. The method has good linearity （ its correlation coefficients 〉 0.99） in the range determined,its relative standard deviations （RSD） are less than 15%, and its recovery is from 87.9% to 128.1% with the lowest quantification limit of 5 ~g/L. This method has been used to measure 15 organic pollutants in wastewater from a certain coking plant. The results show that compared with the conventional method,it can save an hour in pretreatment time. It is a fast, low-cost, accurate, simple and efficient analytical method indeed.

REMOVAL OF ORGANIC POLLUTANTS USING TITANIUM DIOXIDE MEDIATED PHOTOCATALYTIC OXIDATION

A simple and effective method of removing polluted organics in water is reported here.Titanium dioxide is a catalyst in photo-oxidation of monocrotophos.The mechanism of photocatalytic oxidation and the kinetics of the reaction were studied. This same principle also leads to the construction of instrument of PTR-FIA analysis for monitoring organic phosphorus and phosphate in water.

Distribution of persistent organic pollutants in aggregate fractions of a temperate forest and semi-rural soil

The fate of persistent organic pollutants (POPs) and their interactions with aggregates of forest soils are not completely understood. Our objectives here were to quantify the distribution of different POPs in water-stable aggregate fractions and to study their influence on soil organic carbon (Corg) content. Soil samples were taken from a forest-site, Gogerddan (G) and a semi-rural site, Hazelrigg (H) in Great Britain, from 0-2 and 2-5?cm and 0-4 and 8-12?cm soil depth, respectively. POPs analyzed were PAHs, PCBs, total DDT, PBDEs and HCB. The bulk soil analysis showed that the concentration of POPs was significantly higher (p?≤?0.05) in forest site G than in semi-rural site H, particularly at the surface soil levels compared to the subsurface soil depths in both sites. Total concentrations of PCBs and PAHs of both sites were positively correlated with Corg contents. POPs concentrations and Corg, Nt contents of forest site G were significantly higher (p?≤?0.05) in water-stable macro aggregates (>0.25, >1, >2?mm) than the micro aggregates (>0.053?mm). The POP concentrations of all aggregate fractions after normalizing to their respective Corg content were increased due higher contamination and strong sorption by Corg. These results showed a strong effect of Corg on the partitioning of organic pollutants to soil aggregate size fractions. The present study affirms the ecological significance of forest soils act as a potential sink of POPs. In summary, our results suggest that aggregate fractions may promote soil C storage and act as a potential POP sink in surface soil without increasing their concentration in the aggregate fraction of subsoil.

Preparation of calibration standard of organic vapours using the diffusion tube method

This paper describe the theoretical consideration, experimental results and applications of diffusion tube, used for preparing the calibration standard of organic vapours. This dynamic procedure entirely eliminates the adsorption effect, which is important in static procedures. Its concentration range is wider than that of the permeation tube. The diffusion tube technique is therefore a very accurate, simple and easy-to-make device. It is quite useful in the determination of organic pollutants existing in the environment.