This study is concerned with the effects of di （2-ethylhexyl） phthalate （DEHP） on two kinds of duckweeds （Spirodela polyrhiza and Lemna minor）.The results indicate that DEHP has aquatic toxicity to Spirodela pol...This study is concerned with the effects of di （2-ethylhexyl） phthalate （DEHP） on two kinds of duckweeds （Spirodela polyrhiza and Lemna minor）.The results indicate that DEHP has aquatic toxicity to Spirodela polyrhiza at 0.4 mg/L and to Lemna minor at over 0.1 mg/L by changing their physiologic-biochemical characteristics.The contents of duckweed chlorophyll and soluble protein decrease with increasing DEHP concentration after 7 d of exposure.DEHP shows the stimulating role in catalase （CAT） and superoxide dismutase （SOD） systems at relative low levels.At 0.01 mg/L and 0.005 mg/L,SOD activities of Spirodela polyrhiza and Lemna minor reach their peak values respectively,while CAT activity reaches its maximum value at 0.05 mg/L and 0.01 mg/L.When DEHP levels are too high,the protection enzyme system would be destroyed and plant growth is inhibited.The analysis of malondialdehyde （MDA） and Fourier transform infrared spectroscopy manifest that DEHP could affect the tested duckweeds by destroying its cell membranes,and Spirodela polyrhiza is more resistant to DEHP exposure than Lemna minor.展开更多
The widespread use of chemical products inevitably brings many side effects as environmental pollutants.Toxicological assessment of compounds to aquatic life plays an important role in protecting the environment from ...The widespread use of chemical products inevitably brings many side effects as environmental pollutants.Toxicological assessment of compounds to aquatic life plays an important role in protecting the environment from their hazards.However,in vivo animal testing approaches for aquatic toxicity evaluation are timeconsuming,expensive,and ethically limited,especially when there are a great number of compounds.In silico modeling methods can effectively improve the toxicity evaluation efficiency and save costs.Here,we present a web-based server,AquaticTox,which incorporates a series of ensemble models to predict acute toxicity of organic compounds in aquatic organisms,covering Oncorhynchus mykiss,Pimephales promelas,Daphnia magna,Pseudokirchneriella subcapitata,and Tetrahymena pyriformis.The predictive models are built through ensemble learning algorithms based on six base learners.These ensemble models outperform all corresponding single models,achieving area under the curve(AUC)scores of 0.75−0.92.Compared to the best single models,the average precisions of the ensemble models have been increased by 12−22%.Additionally,a self-built knowledge base of the structure-aquatic toxic mode of action(MOA)relationship was integrated into AquaticTox for toxicity mechanism analysis.Hopefully,the user-friendly tool(https://chemyang.ccnu.edu.cn/ccb/server/AquaticTox);could facilitate the identification of aquatic toxic chemicals and the design of green molecules.展开更多
Based on the three-dimensional structures of the compounds,the structures of 48 ester compounds were expressed parametrically.Through multiple linear regression and partial least-squares regression,the relationship mo...Based on the three-dimensional structures of the compounds,the structures of 48 ester compounds were expressed parametrically.Through multiple linear regression and partial least-squares regression,the relationship models between ester compound structures and aquatic toxicity log(1/IGC50)were established.The correlation coefficients(R2)of the models were 0.9974 and 0.9940,and the standard deviations(SD)were 0.0469 and 0.0646,respectively.The stability of the models was evaluated by the leave-one-out internal cross-test.The correlation coefficients(RCV2)of the models of interactive tests were 0.9939 and 0.8952,and the standard deviation(SDCV)was 0.0715 and 0.0925,respectively.The external samples were used to test the predictive ability of the models,and the correlation coefficients(Rtest2)of the external predictions were 0.9955 and 0.9955,and the standard deviations(SDtest)were 0.0720 and 0.0716,respectively.The molecular structure descriptors could successfully represent the structural characteristics of the compounds,and the built models had good fitting effects,strong stability and high prediction accuracy.The present study has a good reference value for the study of the structure-toxicity relationship of toxic compounds in the environment.展开更多
Widespread application of poly-and per-fluoroalkyl substances(PFAS)has resulted in some substances being ubiquitous in environmental matrices.That and their resistance to degradation have allowed them to accumulate in...Widespread application of poly-and per-fluoroalkyl substances(PFAS)has resulted in some substances being ubiquitous in environmental matrices.That and their resistance to degradation have allowed them to accumulate in wildlife and humans with potential for toxic effects.While specific substances of concern have been phased-out or banned,other PFAS that are emerging as alternative substances are still produced and are being released into the environment.This review focuses on describing three emerging,replacement PFAS:perfluoroethylcyclohexane sulphonate(PFECHS),6:2 chlorinated polyfluoroalkyl ether sulfonate(6:2 Cl-PFAES),and hexafluoropropylene oxide dimer acid(HFPO-DA).By summarizing their physicochemical properties,environmental fate and transport,and toxic potencies in comparison to other PFAS compounds,this review offers insight into the viabilities of these chemicals as replacement substances.Using the chemical scoring and ranking assessment model,the relative hazards,uncertainties,and data gaps for each chemical were quantified and related to perfluorooctane sulfonic acid(PFOS)and perfluorooctanoic acid(PFOA)based on their chemical and uncertainty scores.The substances were ranked PFOS>6:2 Cl-PFAES>PFOA>HFPO-DA>PFECHS according to their potential toxicity and PFECHS>HFPO-DA>6:2 Cl-PFAES>PFOS>PFOA according to their need for future research.Since future uses of PFAS remain uncertain in the face of governmental regulations and production bans,replacement PFAS will continue to emerge on the world market and in the environment,raising concerns about their general lack of information on mechanisms and toxic potencies.展开更多
Environmental fate and ecological impacts of fipronil and its transformation products(FIPs)in aquatic environment have caused worldwide attention,however,the influence of dissolved organic carbon(DOC)on multimedia dis...Environmental fate and ecological impacts of fipronil and its transformation products(FIPs)in aquatic environment have caused worldwide attention,however,the influence of dissolved organic carbon(DOC)on multimedia distribution,bioavailability,and toxicity of FIPs in field waterways was largely unknown.Here,we collected 11 companion water and sediment samples along a lotic stream in Guangzhou,South China.FIPs were ubiquitous with total water concentrations ranging from 1.22 to 43.2 ng/L(14.8±12.9 ng/L)and fipronil sulfone was predominant in both water and sediment.More than 70%of FIPs in aqueous phase were bound to DOC and the KDOC values of FIPs were approximately 1–2 orders of magnitude higher than K_(d-s)/K_(OC),emphasizing the significance of DOC in phase partitioning and transport of FIPs in aquatic environment.Water and sediment samples were more toxic to Chironomus dilutus than Hyallela azteca,and FIPs(especially fipronil sulfone)pronouncedly contributed toxicity to C.dilutus.Toxic units(TU)based on freely dissolved concentrations in water determined by solid phase microextraction significantly improved toxicity estimation of FIPs to the invertebrates compared to TUs based on aqueous concentrations.The present study highlights the significance of DOC association on fate and ecological risk of hydrophobic insecticides in lotic ecosystem.展开更多
An environmental risk assessment was performed for pharmaceutical compounds present in the aquatic environment of China. Predicted environmental concentration （PEC） of the compounds were calculated according to Euro...An environmental risk assessment was performed for pharmaceutical compounds present in the aquatic environment of China. Predicted environmental concentration （PEC） of the compounds were calculated according to European Medicines Evaluation Agency （EMEA） guidelines. Available ecotoxicological data compromised by applying a very conservative assessment factor （AF） were employed to calculate the predicted noeffect concentration （PNEC）. The screening principle and the risk assessment were based on risk quotient （RQ）, which derived from the PEC and related PNEC values. PEC results indicated that all the compounds except sulfadimethoxine and levocamitine, should carry out phase II risk assessment in EMEA guideline. RQ values suggested that more than 36 pharmaceuticals may be imposed health threats to the aquatic environment; especially the antibiotic therapeutic class including amoxicillin, sulfasalazine, trimethoprim, oxytetracycline and erythromycin showed high RQ values. These substances with high RQ value （RQ≥ 1） were regarded as top- priority pharmaceuticals for control in the aquatic environment of China. However, the antibiotic substances which had low risk quotient （RQ 〈 1）, should be reassessed by its potentially induced resistance under low concentration in future.展开更多
Endocrine disruptors(EDs)are synthetic or natural chemical molecules occurring in environment that have the potential to impart adverse effects on homeostasis of endocrine axis leading to neurological,developmental,im...Endocrine disruptors(EDs)are synthetic or natural chemical molecules occurring in environment that have the potential to impart adverse effects on homeostasis of endocrine axis leading to neurological,developmental,immunological and reproductive disarray at organismal level.A wide range of structurally diverse EDs such as,sex-steroid hormone mimics,pesticides and fertilizers,prevail in the environment originating from waste of industries,pharmaceutics,sewage treatment plants and agriculture.In addition,some metals,such as Cu,Hg and Zn,have endocrine disrupting potency in their metallic as well as synthesized nano-particulate forms.There is an increasing concern in research for the plausible threat posed by EDs that can disrupt the endocrine system in aquatic fauna as these compounds are frequently discharged or run-off into water stream.Fishes are well known bio-indicators to understand toxicity of EDs as they are vulnerable to endocrine disruption.Furthermore,EDs have the potential to affect fish-feeding higher vertebrates including mammals and subsequently human,as they make their way up on the food web pyramid due to biomagnification.In light of this,several observations suggesting adverse effects of EDs and the mechanism contributing to endocrine disruption in fish are discussed extensively in this review.This article highlights the necessity to choose a credible model for assessing the toxic effects exerted by EDs.Furthermore,the toxic effects of EDs will be comprehensively reviewed with reference to sexual plasticity,neuroendocrine mechanisms,thyroid and immune modulation,gonadal development and maturation as well as changes in transcriptome/genome profile using fish models to imply ED-induced aquatic pollution in a larger perspective.For decades now,studies on EDs have challenged traditional concepts in toxicology to develop new molecular markers to improve methodologies and to assess the ecological risks associated with field conditions.In this regard,it is imperative to highlight the development of modern diagnostic tools including biosensors to monitor the inadvertent usage of EDs and the resultant environmental risks.Lastly,current limitations in knowledge along with future research perspectives in the field are also highlighted in this article.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos.40973073,40830744)the Shanghai Leading Academic Discipline Project (Grant No.S30109)+1 种基金the National Key Technology Research and Development Program in the 11th Five Year Plan of China (Grant Nos.2008BAC32B03,2009BAA24B04)the Natural Science Foundation of the Science and Technology Commission of Shanghai Municipality (Grant No.09ZR1411300)
文摘This study is concerned with the effects of di （2-ethylhexyl） phthalate （DEHP） on two kinds of duckweeds （Spirodela polyrhiza and Lemna minor）.The results indicate that DEHP has aquatic toxicity to Spirodela polyrhiza at 0.4 mg/L and to Lemna minor at over 0.1 mg/L by changing their physiologic-biochemical characteristics.The contents of duckweed chlorophyll and soluble protein decrease with increasing DEHP concentration after 7 d of exposure.DEHP shows the stimulating role in catalase （CAT） and superoxide dismutase （SOD） systems at relative low levels.At 0.01 mg/L and 0.005 mg/L,SOD activities of Spirodela polyrhiza and Lemna minor reach their peak values respectively,while CAT activity reaches its maximum value at 0.05 mg/L and 0.01 mg/L.When DEHP levels are too high,the protection enzyme system would be destroyed and plant growth is inhibited.The analysis of malondialdehyde （MDA） and Fourier transform infrared spectroscopy manifest that DEHP could affect the tested duckweeds by destroying its cell membranes,and Spirodela polyrhiza is more resistant to DEHP exposure than Lemna minor.
基金supported the National Key Research and Development Program of China(2023YFD1700500)National Natural Science Foundation of China(21907036)Postdoctoral Fellowship Program of CPSF(No.GZB20230198).
文摘The widespread use of chemical products inevitably brings many side effects as environmental pollutants.Toxicological assessment of compounds to aquatic life plays an important role in protecting the environment from their hazards.However,in vivo animal testing approaches for aquatic toxicity evaluation are timeconsuming,expensive,and ethically limited,especially when there are a great number of compounds.In silico modeling methods can effectively improve the toxicity evaluation efficiency and save costs.Here,we present a web-based server,AquaticTox,which incorporates a series of ensemble models to predict acute toxicity of organic compounds in aquatic organisms,covering Oncorhynchus mykiss,Pimephales promelas,Daphnia magna,Pseudokirchneriella subcapitata,and Tetrahymena pyriformis.The predictive models are built through ensemble learning algorithms based on six base learners.These ensemble models outperform all corresponding single models,achieving area under the curve(AUC)scores of 0.75−0.92.Compared to the best single models,the average precisions of the ensemble models have been increased by 12−22%.Additionally,a self-built knowledge base of the structure-aquatic toxic mode of action(MOA)relationship was integrated into AquaticTox for toxicity mechanism analysis.Hopefully,the user-friendly tool(https://chemyang.ccnu.edu.cn/ccb/server/AquaticTox);could facilitate the identification of aquatic toxic chemicals and the design of green molecules.
基金the Youth Foundation of Sichuan Provincial Department of Education(18ZB0323)。
文摘Based on the three-dimensional structures of the compounds,the structures of 48 ester compounds were expressed parametrically.Through multiple linear regression and partial least-squares regression,the relationship models between ester compound structures and aquatic toxicity log(1/IGC50)were established.The correlation coefficients(R2)of the models were 0.9974 and 0.9940,and the standard deviations(SD)were 0.0469 and 0.0646,respectively.The stability of the models was evaluated by the leave-one-out internal cross-test.The correlation coefficients(RCV2)of the models of interactive tests were 0.9939 and 0.8952,and the standard deviation(SDCV)was 0.0715 and 0.0925,respectively.The external samples were used to test the predictive ability of the models,and the correlation coefficients(Rtest2)of the external predictions were 0.9955 and 0.9955,and the standard deviations(SDtest)were 0.0720 and 0.0716,respectively.The molecular structure descriptors could successfully represent the structural characteristics of the compounds,and the built models had good fitting effects,strong stability and high prediction accuracy.The present study has a good reference value for the study of the structure-toxicity relationship of toxic compounds in the environment.
基金was supported by a Discovery Grant(Project#326415-07)from the Natural Sciences and Engineering Research Council of Canada.ProfGiesy was supported by the Canada Research Chair Program,and a Distinguished Visiting Professorship in the Department of Environmental Sciences,Baylor University in Waco,TX,USA.Prof.Brinkmann is currently a faculty member of the Global Water Futures(GWF)program,which was funded in part with financial support from the Canada First Research Excellence Funds(CFREF).
文摘Widespread application of poly-and per-fluoroalkyl substances(PFAS)has resulted in some substances being ubiquitous in environmental matrices.That and their resistance to degradation have allowed them to accumulate in wildlife and humans with potential for toxic effects.While specific substances of concern have been phased-out or banned,other PFAS that are emerging as alternative substances are still produced and are being released into the environment.This review focuses on describing three emerging,replacement PFAS:perfluoroethylcyclohexane sulphonate(PFECHS),6:2 chlorinated polyfluoroalkyl ether sulfonate(6:2 Cl-PFAES),and hexafluoropropylene oxide dimer acid(HFPO-DA).By summarizing their physicochemical properties,environmental fate and transport,and toxic potencies in comparison to other PFAS compounds,this review offers insight into the viabilities of these chemicals as replacement substances.Using the chemical scoring and ranking assessment model,the relative hazards,uncertainties,and data gaps for each chemical were quantified and related to perfluorooctane sulfonic acid(PFOS)and perfluorooctanoic acid(PFOA)based on their chemical and uncertainty scores.The substances were ranked PFOS>6:2 Cl-PFAES>PFOA>HFPO-DA>PFECHS according to their potential toxicity and PFECHS>HFPO-DA>6:2 Cl-PFAES>PFOS>PFOA according to their need for future research.Since future uses of PFAS remain uncertain in the face of governmental regulations and production bans,replacement PFAS will continue to emerge on the world market and in the environment,raising concerns about their general lack of information on mechanisms and toxic potencies.
基金supported by the National Natural Science Foundation of China(Nos.U1901220,41977343 and 42007365)Guangzhou Municipal Science and Technology Bureau(No.202103000046)Innovative Research Team of Department of Education of Guangdong Province(No.2020KCXTD005).
文摘Environmental fate and ecological impacts of fipronil and its transformation products(FIPs)in aquatic environment have caused worldwide attention,however,the influence of dissolved organic carbon(DOC)on multimedia distribution,bioavailability,and toxicity of FIPs in field waterways was largely unknown.Here,we collected 11 companion water and sediment samples along a lotic stream in Guangzhou,South China.FIPs were ubiquitous with total water concentrations ranging from 1.22 to 43.2 ng/L(14.8±12.9 ng/L)and fipronil sulfone was predominant in both water and sediment.More than 70%of FIPs in aqueous phase were bound to DOC and the KDOC values of FIPs were approximately 1–2 orders of magnitude higher than K_(d-s)/K_(OC),emphasizing the significance of DOC in phase partitioning and transport of FIPs in aquatic environment.Water and sediment samples were more toxic to Chironomus dilutus than Hyallela azteca,and FIPs(especially fipronil sulfone)pronouncedly contributed toxicity to C.dilutus.Toxic units(TU)based on freely dissolved concentrations in water determined by solid phase microextraction significantly improved toxicity estimation of FIPs to the invertebrates compared to TUs based on aqueous concentrations.The present study highlights the significance of DOC association on fate and ecological risk of hydrophobic insecticides in lotic ecosystem.
基金This work was supported by the National Natural Science Foundation of China （Grant No. 41301572） Tsinghua Univcrsity- Vcolia Environnmcnt Joint Research Center for Advanced Environmental Technology.
文摘An environmental risk assessment was performed for pharmaceutical compounds present in the aquatic environment of China. Predicted environmental concentration （PEC） of the compounds were calculated according to European Medicines Evaluation Agency （EMEA） guidelines. Available ecotoxicological data compromised by applying a very conservative assessment factor （AF） were employed to calculate the predicted noeffect concentration （PNEC）. The screening principle and the risk assessment were based on risk quotient （RQ）, which derived from the PEC and related PNEC values. PEC results indicated that all the compounds except sulfadimethoxine and levocamitine, should carry out phase II risk assessment in EMEA guideline. RQ values suggested that more than 36 pharmaceuticals may be imposed health threats to the aquatic environment; especially the antibiotic therapeutic class including amoxicillin, sulfasalazine, trimethoprim, oxytetracycline and erythromycin showed high RQ values. These substances with high RQ value （RQ≥ 1） were regarded as top- priority pharmaceuticals for control in the aquatic environment of China. However, the antibiotic substances which had low risk quotient （RQ 〈 1）, should be reassessed by its potentially induced resistance under low concentration in future.
基金SK and PS are grateful to the University of Hyderabad for Non-NET fellowships.NA is thankful to the Junior Research Fellowship support by a grant-in-aid(BT/PR15748/AAQ/3/803/2016)from the Department of Biotechnology(DBT)India awarded to BS.BS is also a recipient of TATA innovation fellowship(BT/HRD/35/01/02/2013)from DBT,India(during the years:2014-2019)which is acknowledged.
文摘Endocrine disruptors(EDs)are synthetic or natural chemical molecules occurring in environment that have the potential to impart adverse effects on homeostasis of endocrine axis leading to neurological,developmental,immunological and reproductive disarray at organismal level.A wide range of structurally diverse EDs such as,sex-steroid hormone mimics,pesticides and fertilizers,prevail in the environment originating from waste of industries,pharmaceutics,sewage treatment plants and agriculture.In addition,some metals,such as Cu,Hg and Zn,have endocrine disrupting potency in their metallic as well as synthesized nano-particulate forms.There is an increasing concern in research for the plausible threat posed by EDs that can disrupt the endocrine system in aquatic fauna as these compounds are frequently discharged or run-off into water stream.Fishes are well known bio-indicators to understand toxicity of EDs as they are vulnerable to endocrine disruption.Furthermore,EDs have the potential to affect fish-feeding higher vertebrates including mammals and subsequently human,as they make their way up on the food web pyramid due to biomagnification.In light of this,several observations suggesting adverse effects of EDs and the mechanism contributing to endocrine disruption in fish are discussed extensively in this review.This article highlights the necessity to choose a credible model for assessing the toxic effects exerted by EDs.Furthermore,the toxic effects of EDs will be comprehensively reviewed with reference to sexual plasticity,neuroendocrine mechanisms,thyroid and immune modulation,gonadal development and maturation as well as changes in transcriptome/genome profile using fish models to imply ED-induced aquatic pollution in a larger perspective.For decades now,studies on EDs have challenged traditional concepts in toxicology to develop new molecular markers to improve methodologies and to assess the ecological risks associated with field conditions.In this regard,it is imperative to highlight the development of modern diagnostic tools including biosensors to monitor the inadvertent usage of EDs and the resultant environmental risks.Lastly,current limitations in knowledge along with future research perspectives in the field are also highlighted in this article.
