Pharmaceutical pollution is becoming an increasing threat to aquatic environments since inactive compounds do not break down,and the drug products are accumulated in living organisms.The ability of a drug to dissolve ...Pharmaceutical pollution is becoming an increasing threat to aquatic environments since inactive compounds do not break down,and the drug products are accumulated in living organisms.The ability of a drug to dissolve in water(i.e.,LogS)is an important parameter for assessing a drug’s environmental fate,biovailability,and toxicity.LogS is typically measured in a laboratory setting,which can be costly and time-consuming,and does not provide the opportunity to conduct large-scale analyses.This research develops and evaluates machine learning models that can produce LogS estimates and may improve the environmental risk assessments of toxic pharmaceutical pollutants.We used a dataset from the ChEMBL database that contained 8832 molecular compounds.Various data preprocessing and cleaning techniques were applied(i.e.,removing the missing values),we then recorded chemical properties by normalizing and,even,using some feature selection techniques.We evaluated logS with a total of several machine learning and deep learning models,including;linear regression,random forests(RF),support vector machines(SVM),gradient boosting(GBM),and artificial neural networks(ANNs).We assessed model performance using a series of metrics,including root mean square error(RMSE)and mean absolute error(MAE),as well as the coefficient of determination(R^(2)).The findings show that the Least Angle Regression(LAR)model performed the best with an R^(2) value close to 1.0000,confirming high predictive accuracy.The OMP model performed well with good accuracy(R^(2)=0.8727)while remaining computationally cheap,while other models(e.g.,neural networks,random forests)performed well but were too computationally expensive.Finally,to assess the robustness of the results,an error analysis indicated that residuals were evenly distributed around zero,confirming the results from the LAR model.The current research illustrates the potential of AI in anticipating drug solubility,providing support for green pharmaceutical design and environmental risk assessment.Future work should extend predictions to include degradation and toxicity to enhance predictive power and applicability.展开更多
A series of 9 soil samples were taken at a timber treatment site in SW France where Cu sulphate and chromated copper arsenate (CCA) have been used as wood preservatives (Sites P1 to P9) and one soil sample was col...A series of 9 soil samples were taken at a timber treatment site in SW France where Cu sulphate and chromated copper arsenate (CCA) have been used as wood preservatives (Sites P1 to P9) and one soil sample was collected at an adjacent site on the same soil type (Site P10). Copper was a major contaminant in all topsoils, varying from 65 (Soil P5) to 2600 mg Cu kg^-1 (Soil P7), exceeding background values for French sandy soils. As and Cr did not accumulate in soil, except at Site P8 (52 mg As kg^-1 and 87 mg Cr kg^-1) where CCA-treated posts were stacked. Soil ecotoxicity was assessed with bioassays using radish, lettuce, slug Arion rufus L., and earthworm Dendrobaena octaedra (Savigny). There were significantly differences in lettuce germination rate, lettuce leaf yield, radish root and leaf yields, slug herbivory, and earthworm avoidance. An additional bioassay showed higher negative impacts on bean shoot and root yields, Rhizobium nodule counts on Bean roots, and guaiacol peroxidase activity in primary Bean leaves for soil from Site PT, with and without fertilisation, than for soil from Site P10, despite both soils having a similar value for computed free ion Cu2+ activity in the soil solution (pCu^2+). Beans grown in soil from Site P7 that had been fertilised showed elevated foliar Cu content and phytotoxic symptoms. Soils from Sites P7 (treatment plant) and P6 (storage of treated utility poles) had the highest ecotoxicity, whereas soil from Site P10 (high organic matter content and cation exchange capacity) had the lowest. Except at Site P10, the soil factor pCu^2+ computed with soil pH and total soil Cu could be used to predict soil ecotoxicity.展开更多
Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity...Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration (ECs0) and bioaccumulation factor (BAF). The measurement endpoints used were seed germination and seedling growth (shoot and root). The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.展开更多
This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on ...This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon(PAH)compounds,oxidative potential of ascorbic acid(OP^(AA)),and ecotoxicity through D aphnia pulex mortality test.PM diluted with filtered fresh air(WD)gathered in a minitunel,and particulate matter(PM)collected directly from the exhaust gas stream(W/oD)were used for comparison.Results showed that PM collecting method significantly impact PAH concentration.Although all PAH appeared in both,WD and W/oD,higher concentrations were obtained in the last case.Increasing biodiesel concentration in the fuel blend decreased all PAH compounds,and those with 3 and 5 aromatic rings were the most abundant.Palm biodiesel affected both OP^(AA)and ecotoxicity.While B10 and B20 exhibited the same rate of ascorbic acid(AA)depletion,B100 showed significant faster oxidation rate during the first four minutes and oxidized 10%more AA at the end of the test.B100 and B20 were significantly more ecotoxic than B10.The lethal concentration LC50 for B10 was 6.13 mg/L.It was concluded that palm biodiesel decreased PAH compounds,but increased the oxidative potential and ecotoxicity.展开更多
Nowadays, microalgae are particularly used to assess the environmental impact of contaminants in aquatic systems. Naturally present in some algal species, bioluminescence is highly used in application fields related t...Nowadays, microalgae are particularly used to assess the environmental impact of contaminants in aquatic systems. Naturally present in some algal species, bioluminescence is highly used in application fields related to environmental monitoring. Bioluminescent dinoflagellates have played a pivotal role in this domain. When exposed to heavy metals or toxic organic compounds, bioluminescent dinoflagellates have the capacity to decrease light emission. In addition, new molecular tools allow the possibility to produce genetically modified microorganisms which are able to perform luminescence. Combined with the luciferase reporter gene, two main genetic constructions can be employed. Activation of a specific inducible promoter induces the luminescence gene transcription and this signal increases over time. Constitutive promoters result in a high basal expression level of the reporter gene. During exposure to a potential toxic pollutant, the basal expression level will decrease due to the toxic effect. Toxicity bioassays based on engineered luminescent Chlorophyta microalgae are among the most sensitive tests and are an invaluable complement to classical toxicity assays.展开更多
[Objectives]This study was conducted on the effects of veterinary antibiotics on pasture growth.[Methods]With alfalfa ( Medicago sativa L.) as an experimental material and oxytetracycline,chlortetracycline and enroflo...[Objectives]This study was conducted on the effects of veterinary antibiotics on pasture growth.[Methods]With alfalfa ( Medicago sativa L.) as an experimental material and oxytetracycline,chlortetracycline and enrofloxacin as experimental contaminants,the effects of the three veterinary antibiotics on the germination percentage,germination energy,germination index and vigor index of alfalfa seeds and on the plant height and root length of alfalfa seedlings were study at the concentration gradient of 50,100,150,200 and 250 mg/L,respectively.[Results]The oxytetracycline treatments had no significant effect on the germination percentage of alfalfa seeds,but promoted its germination index.The chlortetracycline treatment solutions and enrofloxacin treatment solutions promoted the germination percentage,germination energy and germination index of alfalfa.The three antibiotics significantly inhibited the vigor index of alfalfa seeds,and had significant inhibitory effects on root length and plant height.[Conclusions]These results provide an important basis for studying the ecotoxicity of veterinary antibiotics on pasture.展开更多
A series of N-acetylated cationic gemini surfactants (3a-e) having dimeric structures derived from tertiary amines were synthesized. Their antifungal potency and surface properties were determined. It also studied the...A series of N-acetylated cationic gemini surfactants (3a-e) having dimeric structures derived from tertiary amines were synthesized. Their antifungal potency and surface properties were determined. It also studied the acute toxicity of the molecule with the best performance and the best water solubility (3e) through Chlorella vulgaris and Daphnia magna bioassays. The results were compared to those obtained for a commercially available reference compound 2-(thiocyanomethylthio) benzothiazole (TCMTB). Parameters such as surface tension (ϒCMC), critical micelle concentration (CMC), surface excess concentration (Γ), and area per molecule (A) were determined. The resulting values indicated that the five gemini surfactants are characterized by good surface-active and self-aggregation properties. All surfactants were tested to evaluate their antifungal activity. Six fungal strains were used to conduct the study. The minimum inhibitory concentration (MIC) value was measured by the fungal growth inhibition. The results of the MICs were compared with two commercially available reference compounds (Fluconazole and TCMTB). The least active molecule was 3e, but 3b and 3d were found to be the most potent compounds with a similar activity for all strains. Candida albicans was the most sensitive one. In contrast, Aspergillus niger was resistant. Ecotoxicity of gemini 3e was assessed: the commercial formulation (TCMTB) was between three and four orders of magnitude more toxic than the gemini one for the biological species tested.展开更多
Xanthates are organic synthesized substances with a potentially wide range of applications. They may serve as essential components of many compounds or materials that also play a vital role in various industrial and s...Xanthates are organic synthesized substances with a potentially wide range of applications. They may serve as essential components of many compounds or materials that also play a vital role in various industrial and socio-economic processes. Addressing the question of the use of xanthates without considering their toxicity, and their decomposition process and products would be ecologically and healthily less sustainable. To date, related information is still dispersed and less known to the public. Therefore, this work provides a comprehensive overview of the existing information on the essentiality, fate, ecotoxicity, and health effects of xanthates and associated compounds. According to available information from scientific, technical, and professional circles, xanthates are diverse, usually with a carbon chain of two to six carbon atoms. They play a crucial role in the sectors of the mining and mineral processing industry, agriculture, wastewater treatment, metal protection, rubber vulcanization, the pharmaceutical industry, and medicine. Xanthates’ degradation under different factors and mechanisms, which determine their fate in the environment, leads to the formation of toxic substances, mainly carbon disulfide, carbonyl sulfide, hydrogen sulfide, and hydrogen peroxide. Xanthates and xanthates degradation products are seriously hazardous to humans, animals, soil and aquatic organisms, enzymatic system, etc. Simultaneous exposure to xanthates and metals results in the magnification or reduction of their toxicity level, depending on the exposed organisms. Such toxicological dimensions should attract more scientific and public attention for more safe production, use, storage, and disposal of xanthates. Due to the high affinity of xanthates for metal, xanthates-modified compounds are efficient metal chelating agents. Such a property should be explored to develop potentially low-cost and effective alternatives for metal removal and recovery from contaminated media. The same applies to developing appropriate methods for the evaluation and management of the simultaneous presence of xanthates and metals in the environment.展开更多
The monitoring of water bodies means the attempt of protecting vulnerable groups of organisms inhabiting streams and rivers. Industrial and domestic discharges may worsen the water quality and affect biological balanc...The monitoring of water bodies means the attempt of protecting vulnerable groups of organisms inhabiting streams and rivers. Industrial and domestic discharges may worsen the water quality and affect biological balance, structure and the functioning of the ecosystem. Cubat?o City, is one of the largest industrial centers in Brazil and in Latin America, where the constant discharge of effluents into Cubat?o River and its tributaries caused a degradation scenario in the hydrographic basin of the region. The objective of this study was to evaluate the acute and chronic effects of surface water from Cubat?o River and two of its tributaries (Perequê and Pil?es) by ecotoxicological assays. In addition, physical chemical parameters were analyzed. Ceriodaphnia dubia and Vibrio fischeri were exposed-organisms during the studied period. The study was conducted between 2010 and 2011 in four campaigns and nine sites along the basin of Cubat?o River. The ecotoxicity was measured by Vibrio fischeri bioluminescence, EC50 values ranging from 31.25% to 71.61%. In contrast, based on a bioequivalence t-test statistical analysis, the results obtained with Ceriodaphnia dubia revealed no toxicity in the sampling sites. A critical analysis of raw data of luminescence was carried out showing higher values during the 2nd campaign. From the numbers obtained for physical-chemical parameters P5 was far the worst due to chlorides, hardness and conductivity. From the Pearson correlation analysis carried out with toxicity to V. fischeri and the physical chemical parameters, the dissolved oxygen in water resulted in a moderate positive correlation. Sediment contamination was also demonstrated in the region.展开更多
Per-and poly-fluoroalkyl substances(PFASs),a class of synthetic chemicals with exceptional chemical and thermal stability,have emerged as persistent environmental contaminants with significant bioaccumulative potentia...Per-and poly-fluoroalkyl substances(PFASs),a class of synthetic chemicals with exceptional chemical and thermal stability,have emerged as persistent environmental contaminants with significant bioaccumulative potential,posing substantial risks to ecosystems and human health.Although the production of perfluorooctanoic acid(PFOA)and perfluorooctanesulfonic acid(PFOS)has been phased out across the world,these compounds persist ubiquitously in all kinds of environmental compartments,with marine ecosystems serving as their ultimate sink.Through a search process,this review identified 420 articles published from September 2004 to September 2024 that systematically examined the distribution patterns and ecotoxicological effects of PFOA and PFOS in marine environments,particularly focusing on their bioaccumulation and ecotoxicity through marine trophic webs.While numerous physico-chemical approaches for remediation of PFAS have been proposed,their practical implementation is limited by substantial economic costs,excessive energy requirements,and low mineralization efficiency.In this context,microbial degradation emerges as a promising,eco-friendly alternative for mitigation of PFAS.Recent advancements in microbial degradation pathways and mechanisms for PFOA and PFOS are critically assessed,while emphasizing the current limitations and prospects of bioremediation strategies in marine environments.Furthermore,potential solutions and outline future research directions are proposed to enhance the efficacy of biological approaches for management of marine PFAS contamination.展开更多
The electroplating industry is the main source of 6:2 chlorinated polyfluorinated ether sulfonate(6:2 Cl-PFESA)pollution,which presents risks to human health and the environment.It is therefore crucial to develop effe...The electroplating industry is the main source of 6:2 chlorinated polyfluorinated ether sulfonate(6:2 Cl-PFESA)pollution,which presents risks to human health and the environment.It is therefore crucial to develop effective 6:2 Cl-PFESA degradation techniques.Persulfate oxidation is a potential treatment method for 6:2 Cl-PFESA due to its outstanding oxidative degradability following the generation of the sulfate radical(SO_(4)^(•−))and hydroxyl radical(•OH).It has proven difficult to acquire a full understanding of the reaction mechanism and formation of intermediate(IM)products through conventional experimental studies because they are costly and time-consuming.Therefore,a theoretical analysis method based on density functional theory(DFT)calculations was applied.The DFT results showed that electron transfer for the degradation of 6:2 Cl-PFESA could be initiated by the protonated sulfate radical(HSO_(4)•,ΔG≠SET=9.16 kcal/mol),rather than SO4•−(ΔG≠SET=41.60 kcal/mol).After desulfonation,the reaction underwent stepwise decarboxylation cycles under the action of•OH,leading to the elimination of the CF_(2) units until there was complete mineralization into HCl,HF,and CO_(2).Furthermore,the IMs and the end products of 6:2 Cl-PFESA were evaluated using ECOSAR and TEST software.The low bioaccumulation of the short-chain IMs meant that they could be considered safe in terms of ecotoxicity and health effects.This research determined the theoretical and mechanistic basis of the effects of persulfate in the treatment of water containing 6:2 Cl-PFESA,and its structural analogues.展开更多
Accelerating the separation of carriers in the heterojunction plays vital role in the photoelectrocatalytic(PEC)process,yet it remains a challenging undertaking.Herein,a MOF-on-MOF based dual S-scheme heterojunction(B...Accelerating the separation of carriers in the heterojunction plays vital role in the photoelectrocatalytic(PEC)process,yet it remains a challenging undertaking.Herein,a MOF-on-MOF based dual S-scheme heterojunction(BiVO_(4)/NH_(2)-MIL-125(Ti)/NH_(2)-MIL-53(Fe),denoted as BVO/NM125/NM53)was rationally designed and prepared for PEC removing and detoxification of organic contaminants(phenol,tetracycline hydrochloride,ciprofloxacin and norfloxacin).The S-scheme heterojunction was double confirmed by DFT calculation and XPS analysis.The charge transfer resistance of BVO/NM125/NM53 photoanode decreases to 1/11 of bare BiVO_(4) photoanode.Meanwhile,the photocurrent densitywas 3 times higher,demonstrating a marked improvement in carrier separation efficiency due to dual S-scheme heterojunction.The photoanode achieved 94.3%removal of phenol within 60 min and maintained stable performance over 10 consecutive cycles,demonstrating good PEC efficiency and structural stability.The BVO/NM125/NM53 photoanode also showed effectiveness in removing antibiotics,with chlorophyll fluorescence imaging confirming a significant reduction in the ecotoxicity of intermediates.For example,wheat seed germination,growth,chlorophyll and Carotenoid production were not affected,which was similar to that of deionized water.Radical trapping experiments and electron paramagnetic resonance(EPR)analysis identified·O_(2)^(-)and·OH as the primary active species.This work demonstrates the effectiveness of developing MOF-on-MOF heterojunctions for visible-light response and enhancing charge separation in PEC.展开更多
The widespread use of personal care products poses significant risks to both ecosystems and human health.The construction of photocatalysts with the advantages of enhanced visible light absorption,efficient charge sep...The widespread use of personal care products poses significant risks to both ecosystems and human health.The construction of photocatalysts with the advantages of enhanced visible light absorption,efficient charge separation and high stability is important for the degradation of persistent environmental pollutants.Herein,we have prepared two D-A heterojunction organic semiconductor photocatalysts:PV-BDTC1:IDTCN/Biochar and PVBDTC2:IDTCN/Biochar by a simple design method that can be widely applied.Under visible light irradiation,PV-BDTC2:IDTCN/Biochar showed better removal ability for indomethacin,with reaction rate constants 14.7 and 5.1 times higher than those of PV-BDTC2:IDTCN and Biochar,respectively.This is attributed to the construction of a heterojunction between the donor and the acceptor,which expands the light absorption range and promotes the separation of photogenerated carriers,thereby giving the material the ability to produce a large number of reactive oxygen species during the photocatalytic reaction.In addition,Biochar well ensures the stability of D-A heterojunction films under long-term operating conditions.This work highlight the potential of natural biomaterials in constructing effective D-A heterojunction organic photocatalysts/adsorbents for combatting water pollution.展开更多
Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in th...Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in the environment.The purpose of this paper is to review the performance,mechanisms,and potential environmental toxicity of biochar,modified biochar and its integration use with other materials in petroleum contaminated soil and water.Specifically,the use of biochar in oil-contaminated water and soil as well as the factors that could influence the removal ability of biochar were systematically evaluated.In addition,the modification and integrated use of biochar for improving the removal efficiency were summarized from the aspects of sorption,biodegradation,chemical degradation,and reusability.Moreover,the functional impacts and associated ecotoxicity of pristine and modified biochars in various environments were demonstrated.Finally,some shortcoming of current approaches,and future research needs were provided for the future direction and challenges of modified biochar research.Overall,this paper gain insight into biochar application in petroleum remediation from the perspectives of performance enhancement and environmental sustainability.展开更多
Pesticide-loaded flexible carriers that allow for deformation and adhesion on crop leaves is an effective way to improve pesticide utilization.In interfacial polymerization,the addition of octaphenyl polyoxyethylene(O...Pesticide-loaded flexible carriers that allow for deformation and adhesion on crop leaves is an effective way to improve pesticide utilization.In interfacial polymerization,the addition of octaphenyl polyoxyethylene(OP)with different hydrophile lipophilic balances(HLBs)into the oil phase can regulate the flexibility of pyraclostrobinloaded microcapsules(MCs).Due to differences in amphiphilicity and molecular structure,OP redistributed on the oil-water two-phases and oil-water interface.With increasing HLB,the proportion of OP entering the aqueous phase increased.Furthermore,more OP with low HLB remained in the oil phase and occupied the oil-water interface,and these OPs participated in and regulated the interfacial polymerization to increase the thickness,reduce the compactness of the shell,and increase the hydroxyl and ether bond contents in the shell.Therefore,pyraclostrobin-loaded MCs with low HLB(11.5-12.5)OP-7 exhibited flexible deformation,strong foliar adhesion,good scouring resistance,and a high control effect on peanut leaf spot,which the disease severity was 3.67.For high HLB(16),OP-21-prepared MCs with compact shells were safer to zebrafish,which the safety index was 23.81.Using the amphiphilicity of OP molecules to drive their redistribution in an encapsulation system to regulate interfacial polymerization is an effective way to control the structure and performance of pesticideloaded MCs.展开更多
The occurrence and impacts of emerging organic contaminants(EOCs)in the aquatic environment have gained widespread attention over the past two decades.Due to large number of potential contaminants,monitoring campaigns...The occurrence and impacts of emerging organic contaminants(EOCs)in the aquatic environment have gained widespread attention over the past two decades.Due to large number of potential contaminants,monitoring campaigns,treatment plants,and proposed regulations should preferentially focus on specific pollutants with the highest potential for ecological and human health effects.In the present study,a multi-criteria screening approach based on hazard and exposure potentials was developed for prioritization of 405 unregulated EOCs already present in Chinese surface water.Hazard potential,exposure potential,and risk quotients for ecological and human health effects were quantitatively analyzed and used to screen contaminants.The hazard potential was defined by contaminant persistence,bioaccumulation,ecotoxicity,and human health effects;similarly,the exposure potential was a function of contaminant concentration and detection frequency.In total,123 compounds passed the preselection process,which involved a priority index equal to the normalized hazard potential multiplied by the normalized exposure potential.Based on the prioritization scheme,11 compounds were identified as top-priority,and 37 chemicals were defined as high-priority.The results obtained by the priority index were compared with four other prioritization schemes based on exposure potential,hazard potential,or risk quotients for ecological effects or human health.The priority index effectively captured and integrated the results from the more simplistic prioritization schemes.Based on identified data gaps,four uncertainty categories were classified to recommend:①regular monitoring,derivation of environmental quality standards,and development of control strategies;②increased monitoring;③fortified hazard assessment;and④increased efforts to collect occurrence and toxicity data.Overall,20 pollutants were recommended as priority EOCs.The prioritized list of contaminants provides the necessary information for authoritative regulations to monitor,control,evaluate,and manage the risks of environmentally-relevant EOCs in Chinese surface water.展开更多
This research aimed to evaluate the alga Scenedesmus obliquus toxicity induced by textiledyeing effluents(TDE).The toxicity indicator of TDE in alga at the physiological(algal growyth),biochemical(chlorophyll-a(Chl-a)...This research aimed to evaluate the alga Scenedesmus obliquus toxicity induced by textiledyeing effluents(TDE).The toxicity indicator of TDE in alga at the physiological(algal growyth),biochemical(chlorophyll-a(Chl-a)synthesis and superoxide dismutase(SOD)activity)and structural(cell membrane integrity)level were investigated.Then we further study the relationship among toxicity indicators at physiological and biochemical level,and supplemented by research on algal biomacromolecules.According to the analysis of various endpoints of the alga,the general sensitivity sequence of toxicity endpoints of Scenedesmus obliquus was:SOD activity>Chl-a synthesis>algal growth.The stimulation rate of SOD activity increased from day 3(57.25%~83.02%)to day 6(57.25%~103.81%),and then decreased on day 15(-4.23%^-32.96%),which indicated that the antioxidant balance system of the algal cells was destroyed.The rate of Chl-a synthesis inhibition increased gradually,reaching19.70%~79.39%on day 15,while the rate of growth inhibition increased from day 3(-12.90%~10.16%)to day 15(-21.27%~72.46%).Moreover,the algal growth inhibition rate was positively correlated with the inhibition rate of SOD activity or Chl-a synthesis,with the correlation coefficients were 0.6713 and 0.5217,respectively.Algal cells would be stimulating to produce excessive reactive oxygen species,which would cause peroxidation in the cells,thereby destroying chloroplasts,inhibiting chlorophyll synthesis and reducing photosynthesis.With increasing exposure time,irreversible damage to algae can lead to death.This study is expected to enhance our understanding of the ecological risks through algal tests caused by TDE.展开更多
Ag3PO4 powders were prepared through a precipitation reaction between AgNO3 and precipitating agent solutions that were prepared by adjusting the amount of H3PO4 in the Na3PO4 solutions. The Ag3PO4 powders prepared fr...Ag3PO4 powders were prepared through a precipitation reaction between AgNO3 and precipitating agent solutions that were prepared by adjusting the amount of H3PO4 in the Na3PO4 solutions. The Ag3PO4 powders prepared from the precipitation solution with a pH of 6 showed the highest photocatalytic activity for decolorizing the methylene blue and rhodamine B dyes. These Ag3PO4 powders were further modified by the addition of KBr solutions to obtain AgBr/Ag3PO4 powders and these photocatalysts can decolorize the anionic dyes as reactive orange and methyl orange. The reactive species involved in the photocatalytic degradation process were evaluated for their inhibitory activity using the appropriate scavengers. After photocatalysis, mass spectrometry confirmed that the dyes were degraded to smaller molecules. The ecotoxicities of the dye solutions before and after treatment were evaluated by studying their ability to inhibit the growth of the bioindicator Chlorella vulgaris.展开更多
Rare earth elements(REE)are applied as micro-fertilizer in large scale in China and there is growing concern about the environmental effects of REE accumulation in soils. Accumulation of REE was simulated in lab by ad...Rare earth elements(REE)are applied as micro-fertilizer in large scale in China and there is growing concern about the environmental effects of REE accumulation in soils. Accumulation of REE was simulated in lab by adding REE to three soils and the survival of Pseudomonas fluorescence X16 strain marked with luxAB gene in soils was detected. Curvilinear regression method was applied to analyze the survival pattern. The stimulation values, EC_(50) and NOEC values for X16 strain were calculated to compare the toxic intensity of REE in different soils. The stimulation(peak)values in red soil, yellow fluovo-aquic soil and yellow cinnamon soil, are 11.55~18.08,(0~2.13), 2.37~4.62 mg·kg^(-1) , respectively. EC_(50) values are 13.47~39.12, 6.59~56.18, 372~1034 (mg·kg^(-1)), respectively.NOEC values are 5.62 ~21.41, 0.00~4.53, 133.3~327.1 mg·kg^(-1), respectively. Tangents values of regression equation of the survival of X16 strain in red soil are the maximum ones indicating that REE accumulation in red soil has stronger inhibitory effects than in other two soils. The soil order, reflecting toxic intensity of REE is as follows: red soil>yellow fluovic-aquic soil>yellow cinnamon soil.展开更多
文摘Pharmaceutical pollution is becoming an increasing threat to aquatic environments since inactive compounds do not break down,and the drug products are accumulated in living organisms.The ability of a drug to dissolve in water(i.e.,LogS)is an important parameter for assessing a drug’s environmental fate,biovailability,and toxicity.LogS is typically measured in a laboratory setting,which can be costly and time-consuming,and does not provide the opportunity to conduct large-scale analyses.This research develops and evaluates machine learning models that can produce LogS estimates and may improve the environmental risk assessments of toxic pharmaceutical pollutants.We used a dataset from the ChEMBL database that contained 8832 molecular compounds.Various data preprocessing and cleaning techniques were applied(i.e.,removing the missing values),we then recorded chemical properties by normalizing and,even,using some feature selection techniques.We evaluated logS with a total of several machine learning and deep learning models,including;linear regression,random forests(RF),support vector machines(SVM),gradient boosting(GBM),and artificial neural networks(ANNs).We assessed model performance using a series of metrics,including root mean square error(RMSE)and mean absolute error(MAE),as well as the coefficient of determination(R^(2)).The findings show that the Least Angle Regression(LAR)model performed the best with an R^(2) value close to 1.0000,confirming high predictive accuracy.The OMP model performed well with good accuracy(R^(2)=0.8727)while remaining computationally cheap,while other models(e.g.,neural networks,random forests)performed well but were too computationally expensive.Finally,to assess the robustness of the results,an error analysis indicated that residuals were evenly distributed around zero,confirming the results from the LAR model.The current research illustrates the potential of AI in anticipating drug solubility,providing support for green pharmaceutical design and environmental risk assessment.Future work should extend predictions to include degradation and toxicity to enhance predictive power and applicability.
基金Project supported by the French Agency for Environment and Energy (ADEME)Department of Polluted Soils and Sites, Angers, France (No.ADEME 05 72 C0018/INRA 22000033)
文摘A series of 9 soil samples were taken at a timber treatment site in SW France where Cu sulphate and chromated copper arsenate (CCA) have been used as wood preservatives (Sites P1 to P9) and one soil sample was collected at an adjacent site on the same soil type (Site P10). Copper was a major contaminant in all topsoils, varying from 65 (Soil P5) to 2600 mg Cu kg^-1 (Soil P7), exceeding background values for French sandy soils. As and Cr did not accumulate in soil, except at Site P8 (52 mg As kg^-1 and 87 mg Cr kg^-1) where CCA-treated posts were stacked. Soil ecotoxicity was assessed with bioassays using radish, lettuce, slug Arion rufus L., and earthworm Dendrobaena octaedra (Savigny). There were significantly differences in lettuce germination rate, lettuce leaf yield, radish root and leaf yields, slug herbivory, and earthworm avoidance. An additional bioassay showed higher negative impacts on bean shoot and root yields, Rhizobium nodule counts on Bean roots, and guaiacol peroxidase activity in primary Bean leaves for soil from Site PT, with and without fertilisation, than for soil from Site P10, despite both soils having a similar value for computed free ion Cu2+ activity in the soil solution (pCu^2+). Beans grown in soil from Site P7 that had been fertilised showed elevated foliar Cu content and phytotoxic symptoms. Soils from Sites P7 (treatment plant) and P6 (storage of treated utility poles) had the highest ecotoxicity, whereas soil from Site P10 (high organic matter content and cation exchange capacity) had the lowest. Except at Site P10, the soil factor pCu^2+ computed with soil pH and total soil Cu could be used to predict soil ecotoxicity.
基金Under the auspices of the Key Innovation Program of Chinese Academy of Sciences(No.KZCX1-SW-19-4-01)the National Key Basic Research and Development Program of China(No.2004CB41850407)
文摘Ecotoxicity and bioavailability of cadmium (Cd) to the maize (Zea mays L.) and the soybean (Glycine max (L.) Merr.) were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration (ECs0) and bioaccumulation factor (BAF). The measurement endpoints used were seed germination and seedling growth (shoot and root). The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.
基金the financial support provided by the Colombia Scientific Program within the framework of the call Ecosistema Cientifico(Contract No.FP44842–218–2018)Co-author Silvana Arias wish to thank Colombian Ministry of Science and Technology for her PhD scholarship(Bicentenary doctoral excellence scholarship program)。
文摘This work assessed the impact of fuelling an automotive engine with palm biodiesel(pure,and two blends of 10%and 20%with diesel,B100,B10 and B20,respectively)operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon(PAH)compounds,oxidative potential of ascorbic acid(OP^(AA)),and ecotoxicity through D aphnia pulex mortality test.PM diluted with filtered fresh air(WD)gathered in a minitunel,and particulate matter(PM)collected directly from the exhaust gas stream(W/oD)were used for comparison.Results showed that PM collecting method significantly impact PAH concentration.Although all PAH appeared in both,WD and W/oD,higher concentrations were obtained in the last case.Increasing biodiesel concentration in the fuel blend decreased all PAH compounds,and those with 3 and 5 aromatic rings were the most abundant.Palm biodiesel affected both OP^(AA)and ecotoxicity.While B10 and B20 exhibited the same rate of ascorbic acid(AA)depletion,B100 showed significant faster oxidation rate during the first four minutes and oxidized 10%more AA at the end of the test.B100 and B20 were significantly more ecotoxic than B10.The lethal concentration LC50 for B10 was 6.13 mg/L.It was concluded that palm biodiesel decreased PAH compounds,but increased the oxidative potential and ecotoxicity.
文摘Nowadays, microalgae are particularly used to assess the environmental impact of contaminants in aquatic systems. Naturally present in some algal species, bioluminescence is highly used in application fields related to environmental monitoring. Bioluminescent dinoflagellates have played a pivotal role in this domain. When exposed to heavy metals or toxic organic compounds, bioluminescent dinoflagellates have the capacity to decrease light emission. In addition, new molecular tools allow the possibility to produce genetically modified microorganisms which are able to perform luminescence. Combined with the luciferase reporter gene, two main genetic constructions can be employed. Activation of a specific inducible promoter induces the luminescence gene transcription and this signal increases over time. Constitutive promoters result in a high basal expression level of the reporter gene. During exposure to a potential toxic pollutant, the basal expression level will decrease due to the toxic effect. Toxicity bioassays based on engineered luminescent Chlorophyta microalgae are among the most sensitive tests and are an invaluable complement to classical toxicity assays.
基金Supported by Higher Education of Changchun Normal University([2018]53)
文摘[Objectives]This study was conducted on the effects of veterinary antibiotics on pasture growth.[Methods]With alfalfa ( Medicago sativa L.) as an experimental material and oxytetracycline,chlortetracycline and enrofloxacin as experimental contaminants,the effects of the three veterinary antibiotics on the germination percentage,germination energy,germination index and vigor index of alfalfa seeds and on the plant height and root length of alfalfa seedlings were study at the concentration gradient of 50,100,150,200 and 250 mg/L,respectively.[Results]The oxytetracycline treatments had no significant effect on the germination percentage of alfalfa seeds,but promoted its germination index.The chlortetracycline treatment solutions and enrofloxacin treatment solutions promoted the germination percentage,germination energy and germination index of alfalfa.The three antibiotics significantly inhibited the vigor index of alfalfa seeds,and had significant inhibitory effects on root length and plant height.[Conclusions]These results provide an important basis for studying the ecotoxicity of veterinary antibiotics on pasture.
文摘A series of N-acetylated cationic gemini surfactants (3a-e) having dimeric structures derived from tertiary amines were synthesized. Their antifungal potency and surface properties were determined. It also studied the acute toxicity of the molecule with the best performance and the best water solubility (3e) through Chlorella vulgaris and Daphnia magna bioassays. The results were compared to those obtained for a commercially available reference compound 2-(thiocyanomethylthio) benzothiazole (TCMTB). Parameters such as surface tension (ϒCMC), critical micelle concentration (CMC), surface excess concentration (Γ), and area per molecule (A) were determined. The resulting values indicated that the five gemini surfactants are characterized by good surface-active and self-aggregation properties. All surfactants were tested to evaluate their antifungal activity. Six fungal strains were used to conduct the study. The minimum inhibitory concentration (MIC) value was measured by the fungal growth inhibition. The results of the MICs were compared with two commercially available reference compounds (Fluconazole and TCMTB). The least active molecule was 3e, but 3b and 3d were found to be the most potent compounds with a similar activity for all strains. Candida albicans was the most sensitive one. In contrast, Aspergillus niger was resistant. Ecotoxicity of gemini 3e was assessed: the commercial formulation (TCMTB) was between three and four orders of magnitude more toxic than the gemini one for the biological species tested.
文摘Xanthates are organic synthesized substances with a potentially wide range of applications. They may serve as essential components of many compounds or materials that also play a vital role in various industrial and socio-economic processes. Addressing the question of the use of xanthates without considering their toxicity, and their decomposition process and products would be ecologically and healthily less sustainable. To date, related information is still dispersed and less known to the public. Therefore, this work provides a comprehensive overview of the existing information on the essentiality, fate, ecotoxicity, and health effects of xanthates and associated compounds. According to available information from scientific, technical, and professional circles, xanthates are diverse, usually with a carbon chain of two to six carbon atoms. They play a crucial role in the sectors of the mining and mineral processing industry, agriculture, wastewater treatment, metal protection, rubber vulcanization, the pharmaceutical industry, and medicine. Xanthates’ degradation under different factors and mechanisms, which determine their fate in the environment, leads to the formation of toxic substances, mainly carbon disulfide, carbonyl sulfide, hydrogen sulfide, and hydrogen peroxide. Xanthates and xanthates degradation products are seriously hazardous to humans, animals, soil and aquatic organisms, enzymatic system, etc. Simultaneous exposure to xanthates and metals results in the magnification or reduction of their toxicity level, depending on the exposed organisms. Such toxicological dimensions should attract more scientific and public attention for more safe production, use, storage, and disposal of xanthates. Due to the high affinity of xanthates for metal, xanthates-modified compounds are efficient metal chelating agents. Such a property should be explored to develop potentially low-cost and effective alternatives for metal removal and recovery from contaminated media. The same applies to developing appropriate methods for the evaluation and management of the simultaneous presence of xanthates and metals in the environment.
文摘The monitoring of water bodies means the attempt of protecting vulnerable groups of organisms inhabiting streams and rivers. Industrial and domestic discharges may worsen the water quality and affect biological balance, structure and the functioning of the ecosystem. Cubat?o City, is one of the largest industrial centers in Brazil and in Latin America, where the constant discharge of effluents into Cubat?o River and its tributaries caused a degradation scenario in the hydrographic basin of the region. The objective of this study was to evaluate the acute and chronic effects of surface water from Cubat?o River and two of its tributaries (Perequê and Pil?es) by ecotoxicological assays. In addition, physical chemical parameters were analyzed. Ceriodaphnia dubia and Vibrio fischeri were exposed-organisms during the studied period. The study was conducted between 2010 and 2011 in four campaigns and nine sites along the basin of Cubat?o River. The ecotoxicity was measured by Vibrio fischeri bioluminescence, EC50 values ranging from 31.25% to 71.61%. In contrast, based on a bioequivalence t-test statistical analysis, the results obtained with Ceriodaphnia dubia revealed no toxicity in the sampling sites. A critical analysis of raw data of luminescence was carried out showing higher values during the 2nd campaign. From the numbers obtained for physical-chemical parameters P5 was far the worst due to chlorides, hardness and conductivity. From the Pearson correlation analysis carried out with toxicity to V. fischeri and the physical chemical parameters, the dissolved oxygen in water resulted in a moderate positive correlation. Sediment contamination was also demonstrated in the region.
基金supported by the National Natural Science Foundation of China(No.42077335).
文摘Per-and poly-fluoroalkyl substances(PFASs),a class of synthetic chemicals with exceptional chemical and thermal stability,have emerged as persistent environmental contaminants with significant bioaccumulative potential,posing substantial risks to ecosystems and human health.Although the production of perfluorooctanoic acid(PFOA)and perfluorooctanesulfonic acid(PFOS)has been phased out across the world,these compounds persist ubiquitously in all kinds of environmental compartments,with marine ecosystems serving as their ultimate sink.Through a search process,this review identified 420 articles published from September 2004 to September 2024 that systematically examined the distribution patterns and ecotoxicological effects of PFOA and PFOS in marine environments,particularly focusing on their bioaccumulation and ecotoxicity through marine trophic webs.While numerous physico-chemical approaches for remediation of PFAS have been proposed,their practical implementation is limited by substantial economic costs,excessive energy requirements,and low mineralization efficiency.In this context,microbial degradation emerges as a promising,eco-friendly alternative for mitigation of PFAS.Recent advancements in microbial degradation pathways and mechanisms for PFOA and PFOS are critically assessed,while emphasizing the current limitations and prospects of bioremediation strategies in marine environments.Furthermore,potential solutions and outline future research directions are proposed to enhance the efficacy of biological approaches for management of marine PFAS contamination.
基金This work was supported by the National Natural Science Foundation of China(Grant No.U20A20146,Grant No.52200198)the Natural Science Foundation of Shandong Province(Grant No.ZR2021QB186).
文摘The electroplating industry is the main source of 6:2 chlorinated polyfluorinated ether sulfonate(6:2 Cl-PFESA)pollution,which presents risks to human health and the environment.It is therefore crucial to develop effective 6:2 Cl-PFESA degradation techniques.Persulfate oxidation is a potential treatment method for 6:2 Cl-PFESA due to its outstanding oxidative degradability following the generation of the sulfate radical(SO_(4)^(•−))and hydroxyl radical(•OH).It has proven difficult to acquire a full understanding of the reaction mechanism and formation of intermediate(IM)products through conventional experimental studies because they are costly and time-consuming.Therefore,a theoretical analysis method based on density functional theory(DFT)calculations was applied.The DFT results showed that electron transfer for the degradation of 6:2 Cl-PFESA could be initiated by the protonated sulfate radical(HSO_(4)•,ΔG≠SET=9.16 kcal/mol),rather than SO4•−(ΔG≠SET=41.60 kcal/mol).After desulfonation,the reaction underwent stepwise decarboxylation cycles under the action of•OH,leading to the elimination of the CF_(2) units until there was complete mineralization into HCl,HF,and CO_(2).Furthermore,the IMs and the end products of 6:2 Cl-PFESA were evaluated using ECOSAR and TEST software.The low bioaccumulation of the short-chain IMs meant that they could be considered safe in terms of ecotoxicity and health effects.This research determined the theoretical and mechanistic basis of the effects of persulfate in the treatment of water containing 6:2 Cl-PFESA,and its structural analogues.
基金supported by the National Natural Science Foundation of China(Nos.22276168 and 21876154)A Project Supported by Scientific Research Fund of Zhejiang Provincial Education Department(No.Y202456226)。
文摘Accelerating the separation of carriers in the heterojunction plays vital role in the photoelectrocatalytic(PEC)process,yet it remains a challenging undertaking.Herein,a MOF-on-MOF based dual S-scheme heterojunction(BiVO_(4)/NH_(2)-MIL-125(Ti)/NH_(2)-MIL-53(Fe),denoted as BVO/NM125/NM53)was rationally designed and prepared for PEC removing and detoxification of organic contaminants(phenol,tetracycline hydrochloride,ciprofloxacin and norfloxacin).The S-scheme heterojunction was double confirmed by DFT calculation and XPS analysis.The charge transfer resistance of BVO/NM125/NM53 photoanode decreases to 1/11 of bare BiVO_(4) photoanode.Meanwhile,the photocurrent densitywas 3 times higher,demonstrating a marked improvement in carrier separation efficiency due to dual S-scheme heterojunction.The photoanode achieved 94.3%removal of phenol within 60 min and maintained stable performance over 10 consecutive cycles,demonstrating good PEC efficiency and structural stability.The BVO/NM125/NM53 photoanode also showed effectiveness in removing antibiotics,with chlorophyll fluorescence imaging confirming a significant reduction in the ecotoxicity of intermediates.For example,wheat seed germination,growth,chlorophyll and Carotenoid production were not affected,which was similar to that of deionized water.Radical trapping experiments and electron paramagnetic resonance(EPR)analysis identified·O_(2)^(-)and·OH as the primary active species.This work demonstrates the effectiveness of developing MOF-on-MOF heterojunctions for visible-light response and enhancing charge separation in PEC.
基金supported by Guangxi Science and Technology Major Program(No.AA24206037)the Training Project of High-level Professional and Technical Talents of Guangxi University and Natural Science and Technology Innovation Development Multiplication Program of Guangxi University(No.2022BZRC006)+2 种基金the project of the Research on the electrochemical reaction mechanism of the anode of medium-lowtemperature direct ammonia SOFCs(No.20231063020006)the project of all solid-state high energy density energy storage system(No.20221063010031)the project of Shenzhen Overseas Talent upon Industrialization of 1 kw stack for direct ammonia SOFCs(No.20221061010002).
文摘The widespread use of personal care products poses significant risks to both ecosystems and human health.The construction of photocatalysts with the advantages of enhanced visible light absorption,efficient charge separation and high stability is important for the degradation of persistent environmental pollutants.Herein,we have prepared two D-A heterojunction organic semiconductor photocatalysts:PV-BDTC1:IDTCN/Biochar and PVBDTC2:IDTCN/Biochar by a simple design method that can be widely applied.Under visible light irradiation,PV-BDTC2:IDTCN/Biochar showed better removal ability for indomethacin,with reaction rate constants 14.7 and 5.1 times higher than those of PV-BDTC2:IDTCN and Biochar,respectively.This is attributed to the construction of a heterojunction between the donor and the acceptor,which expands the light absorption range and promotes the separation of photogenerated carriers,thereby giving the material the ability to produce a large number of reactive oxygen species during the photocatalytic reaction.In addition,Biochar well ensures the stability of D-A heterojunction films under long-term operating conditions.This work highlight the potential of natural biomaterials in constructing effective D-A heterojunction organic photocatalysts/adsorbents for combatting water pollution.
基金supported by the Yunnan Fundamental Research Projects(No.202201BE070001-043)the Yunnan Provincial Excellent Young Scientists Fund(No.202201AW070006)+1 种基金USDA-NRCS(No.NR217217XXXXG004)the USDA National Institute of Food and Agriculture Hatch Project(No.7003969)。
文摘Petroleum contamination is considered as a major risk to the health of humans and environment.Biochars as low-cost and eco-friendly carbon materials,have been widely used for the removal of petroleum hydrocarbon in the environment.The purpose of this paper is to review the performance,mechanisms,and potential environmental toxicity of biochar,modified biochar and its integration use with other materials in petroleum contaminated soil and water.Specifically,the use of biochar in oil-contaminated water and soil as well as the factors that could influence the removal ability of biochar were systematically evaluated.In addition,the modification and integrated use of biochar for improving the removal efficiency were summarized from the aspects of sorption,biodegradation,chemical degradation,and reusability.Moreover,the functional impacts and associated ecotoxicity of pristine and modified biochars in various environments were demonstrated.Finally,some shortcoming of current approaches,and future research needs were provided for the future direction and challenges of modified biochar research.Overall,this paper gain insight into biochar application in petroleum remediation from the perspectives of performance enhancement and environmental sustainability.
基金supported by the National Natural Science of China(32272596)Key Research Development Program of Shandong Province(2022CXGC020710)+2 种基金Shandong Province Agricultural Major Technology Collaborative Promotion Plan(SDNYXTTG-2023-20)Central Publicinterest Scientific Institution Basal Research Fund(No.1610232023005)Major technology projects[110202201029(LS-13)].
文摘Pesticide-loaded flexible carriers that allow for deformation and adhesion on crop leaves is an effective way to improve pesticide utilization.In interfacial polymerization,the addition of octaphenyl polyoxyethylene(OP)with different hydrophile lipophilic balances(HLBs)into the oil phase can regulate the flexibility of pyraclostrobinloaded microcapsules(MCs).Due to differences in amphiphilicity and molecular structure,OP redistributed on the oil-water two-phases and oil-water interface.With increasing HLB,the proportion of OP entering the aqueous phase increased.Furthermore,more OP with low HLB remained in the oil phase and occupied the oil-water interface,and these OPs participated in and regulated the interfacial polymerization to increase the thickness,reduce the compactness of the shell,and increase the hydroxyl and ether bond contents in the shell.Therefore,pyraclostrobin-loaded MCs with low HLB(11.5-12.5)OP-7 exhibited flexible deformation,strong foliar adhesion,good scouring resistance,and a high control effect on peanut leaf spot,which the disease severity was 3.67.For high HLB(16),OP-21-prepared MCs with compact shells were safer to zebrafish,which the safety index was 23.81.Using the amphiphilicity of OP molecules to drive their redistribution in an encapsulation system to regulate interfacial polymerization is an effective way to control the structure and performance of pesticideloaded MCs.
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment in China (2017ZX07202)Beijing Science and Technology Planning Project (Z191100006919003)
文摘The occurrence and impacts of emerging organic contaminants(EOCs)in the aquatic environment have gained widespread attention over the past two decades.Due to large number of potential contaminants,monitoring campaigns,treatment plants,and proposed regulations should preferentially focus on specific pollutants with the highest potential for ecological and human health effects.In the present study,a multi-criteria screening approach based on hazard and exposure potentials was developed for prioritization of 405 unregulated EOCs already present in Chinese surface water.Hazard potential,exposure potential,and risk quotients for ecological and human health effects were quantitatively analyzed and used to screen contaminants.The hazard potential was defined by contaminant persistence,bioaccumulation,ecotoxicity,and human health effects;similarly,the exposure potential was a function of contaminant concentration and detection frequency.In total,123 compounds passed the preselection process,which involved a priority index equal to the normalized hazard potential multiplied by the normalized exposure potential.Based on the prioritization scheme,11 compounds were identified as top-priority,and 37 chemicals were defined as high-priority.The results obtained by the priority index were compared with four other prioritization schemes based on exposure potential,hazard potential,or risk quotients for ecological effects or human health.The priority index effectively captured and integrated the results from the more simplistic prioritization schemes.Based on identified data gaps,four uncertainty categories were classified to recommend:①regular monitoring,derivation of environmental quality standards,and development of control strategies;②increased monitoring;③fortified hazard assessment;and④increased efforts to collect occurrence and toxicity data.Overall,20 pollutants were recommended as priority EOCs.The prioritized list of contaminants provides the necessary information for authoritative regulations to monitor,control,evaluate,and manage the risks of environmentally-relevant EOCs in Chinese surface water.
基金supported by the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Z032)the Natural Science Foundation of China(No.21577027)+1 种基金the 2017 Central Special Fund for SoilPreliminary Study on Harmless Treatment and Comprehensive Utilization of Tailings in Dabao Mountain(No.18HK0108)
文摘This research aimed to evaluate the alga Scenedesmus obliquus toxicity induced by textiledyeing effluents(TDE).The toxicity indicator of TDE in alga at the physiological(algal growyth),biochemical(chlorophyll-a(Chl-a)synthesis and superoxide dismutase(SOD)activity)and structural(cell membrane integrity)level were investigated.Then we further study the relationship among toxicity indicators at physiological and biochemical level,and supplemented by research on algal biomacromolecules.According to the analysis of various endpoints of the alga,the general sensitivity sequence of toxicity endpoints of Scenedesmus obliquus was:SOD activity>Chl-a synthesis>algal growth.The stimulation rate of SOD activity increased from day 3(57.25%~83.02%)to day 6(57.25%~103.81%),and then decreased on day 15(-4.23%^-32.96%),which indicated that the antioxidant balance system of the algal cells was destroyed.The rate of Chl-a synthesis inhibition increased gradually,reaching19.70%~79.39%on day 15,while the rate of growth inhibition increased from day 3(-12.90%~10.16%)to day 15(-21.27%~72.46%).Moreover,the algal growth inhibition rate was positively correlated with the inhibition rate of SOD activity or Chl-a synthesis,with the correlation coefficients were 0.6713 and 0.5217,respectively.Algal cells would be stimulating to produce excessive reactive oxygen species,which would cause peroxidation in the cells,thereby destroying chloroplasts,inhibiting chlorophyll synthesis and reducing photosynthesis.With increasing exposure time,irreversible damage to algae can lead to death.This study is expected to enhance our understanding of the ecological risks through algal tests caused by TDE.
基金supported from Prince of Songkla University under contract number SCI570276Sthe Center of Excellence for Innovation in Chemistry(PERCH-CIC), Office of the Higher Education Commission, Ministry of Education
文摘Ag3PO4 powders were prepared through a precipitation reaction between AgNO3 and precipitating agent solutions that were prepared by adjusting the amount of H3PO4 in the Na3PO4 solutions. The Ag3PO4 powders prepared from the precipitation solution with a pH of 6 showed the highest photocatalytic activity for decolorizing the methylene blue and rhodamine B dyes. These Ag3PO4 powders were further modified by the addition of KBr solutions to obtain AgBr/Ag3PO4 powders and these photocatalysts can decolorize the anionic dyes as reactive orange and methyl orange. The reactive species involved in the photocatalytic degradation process were evaluated for their inhibitory activity using the appropriate scavengers. After photocatalysis, mass spectrometry confirmed that the dyes were degraded to smaller molecules. The ecotoxicities of the dye solutions before and after treatment were evaluated by studying their ability to inhibit the growth of the bioindicator Chlorella vulgaris.
文摘Rare earth elements(REE)are applied as micro-fertilizer in large scale in China and there is growing concern about the environmental effects of REE accumulation in soils. Accumulation of REE was simulated in lab by adding REE to three soils and the survival of Pseudomonas fluorescence X16 strain marked with luxAB gene in soils was detected. Curvilinear regression method was applied to analyze the survival pattern. The stimulation values, EC_(50) and NOEC values for X16 strain were calculated to compare the toxic intensity of REE in different soils. The stimulation(peak)values in red soil, yellow fluovo-aquic soil and yellow cinnamon soil, are 11.55~18.08,(0~2.13), 2.37~4.62 mg·kg^(-1) , respectively. EC_(50) values are 13.47~39.12, 6.59~56.18, 372~1034 (mg·kg^(-1)), respectively.NOEC values are 5.62 ~21.41, 0.00~4.53, 133.3~327.1 mg·kg^(-1), respectively. Tangents values of regression equation of the survival of X16 strain in red soil are the maximum ones indicating that REE accumulation in red soil has stronger inhibitory effects than in other two soils. The soil order, reflecting toxic intensity of REE is as follows: red soil>yellow fluovic-aquic soil>yellow cinnamon soil.