Urban rainwater runoff is an important source of nonpoint source pollution due to its transport of diverse contaminants,including polycyclic aromatic hydrocarbons(PAHs)and chlorinated derivatives.Importantly,these chl...Urban rainwater runoff is an important source of nonpoint source pollution due to its transport of diverse contaminants,including polycyclic aromatic hydrocarbons(PAHs)and chlorinated derivatives.Importantly,these chlorinated polycyclic aromatic hydrocarbons(Cl-PAHs)exhibit elevated toxicological potential compared to their non-halogenated parent compounds.In this study,we proposed an approach that combined multivariate receptor model with integration of SHapley Additive exPlanations and Random Forest model.This method identifies the possible sources and reveals the impact of source apportionment results and environmental driving factors(such as geographical and meteorological data)on pollutant concentrations.Sixteen PAHs and nine ClPAHs were detected in 79 runoff samples from all three sites.TheΣ_(16)PAHs average concentration(2923.93 to 6071.83 ng/L)was significantly higher than theΣ_(9)Cl-PAHs(384.34 to 1314.73 ng/L).The source apportionment was conducted by positive matrix factorization(PMF),and six potential pollution sources for PAHs and three for Cl-PAHs were quantified.PAHs primarily originate from the combustion of fossil fuels such as traffic,industrial emissions and coal tar,while Cl-PAHs are mainly derived from atmospheric deposition and industrial emissions.Meanwhile,the self‑organizing map classified PAHs and Cl-PAHs into 2 and 3 groups,respectively.The k-means algorithm yielded 4 clusters for runoff samples.Among machine learning models,Random Forest(RF)demonstrated optimal predictive performance and integrated with SHapley Additive exPlanations(RF-SHAP)revealed the effects of driving factors on the predicted concentration of PAHs and Cl-PAHs in urban runoff samples.展开更多
Microbial degradation is the primary mechanism for purifying polycyclic aromatic hydrocarbon(PAH)contamination in environments,and biochar immobilization is an effective technology to enhance biodegradation,but the pr...Microbial degradation is the primary mechanism for purifying polycyclic aromatic hydrocarbon(PAH)contamination in environments,and biochar immobilization is an effective technology to enhance biodegradation,but the process parameters of the immobilization technology still require further systematic evaluation.Here,biochars derived from pig manure(PM),bamboo(BB),rice straw(RS),and soybean straw(SS)were used as carriers of Mycobacterium sp.ZL7,and the optimal biochar dosage of 1:30(w/V)and immobilization time of 24 h were determined.The immobilization effects followed the order of RS>SS>PM>BB.Scanning electron microscopy and physicochemical properties revealed that porous structures acted as shelters for bacteria,and high nitrogen content,large pore size and high-water holding capacity played important driving roles in immobilization.In the single-substrate system,pyrene removal rates of the PM-,RS-and SS-immobilized materials were greater than 96%,which were significantly higher than those of the biochar alone or the free strain.An orthogonal design experiment in historically PAH-contaminated soil further revealed that,compared with free strains,immobilized materials combined with high moisture content and moderate salicylic acid or Brij 30 can effectively increase the abundance of bacteria and the nidA gene,and enhance the dehydrogenase and polyphenol oxidase activities.The removal rate of total PAHs increased by 8.53%-30.45%after 24 d.Moreover,biochar with strong immobilization capacity showed better PAH removal effects.This study provides a scientific basis and practical reference for biochar-immobilized microorganisms to enhance the self-purification of PAH-contaminated soil.展开更多
This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycy...This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycyclic aromatic hydrocarbons(PAHs)from aqueous solutions.The Chitosan(CS)hydrogel beads were modified with single/twin-tailed anionic surfactants,sodium dodecyl sulfate(SDS)and sodium bis(2-ethylhexyl)sulfosuccinate(AOT),and cationic surfactants,dodecyltrimethylammonium bromide(DTAB)and didodecyldimethylammonium bromide(DDAB),to enhance their adsorption capacity of PAHs.The CS and SMCS beads were evaluated for their structural,mechanical,and adsorption properties using a range of techniques,including infrared spectroscopy(IR),energy-dispersive X-ray spectroscopy(EDX),rheometry,and field emission scanning electron microscopy(FESEM).Adsorption experiments of naphthalene(Nap),acenaphthene(Ace),and phenanthrene(Phe)on SMCS beads demonstrate that they have significantly higher adsorption capacities than CS beads,due to increase in hydrophobic interactions.Adsorption capacity followed the trend,Phen>Ace>Nap for all the beads revealing that twin-tailed SMCS bead possess much higher adsorption capacities(Qmax)compared to single-tailed SMCS beads.For twin tailed surfactants,the maximum adsorption capacities for Nap,Ace and Phe varied as CS-AOT(CS-DDAB):430.0(323.8)611.60(538.18)633.39(536.99)mg/g respectively,outperforming other reported hydrogel beads.The study highlights the simplicity,eco-friendliness,and enhanced performance of surfactant modification for developing high-efficiency adsorbents,paving the way for cost-effective solutions in water re-mediation.展开更多
Studies on the elevation gradient distribution of polycyclic aromatic hydrocarbons(PAHs)have mainly focused on high-altitude regions like the Tibetan Plateau.Investigation of the PAHs distribution in Shennongjia regio...Studies on the elevation gradient distribution of polycyclic aromatic hydrocarbons(PAHs)have mainly focused on high-altitude regions like the Tibetan Plateau.Investigation of the PAHs distribution in Shennongjia region and the effects of total organic carbon(TOC),black carbon(BC)and elevation gradient on PAHs distribution are of great practical significance for protecting the Tibetan Plateau’s environment.This study collected soil and peat samples across varying vegetation types and altitudes in Shennongjia.Results showed that theΣ16PAHs concentrations ranged from 15.44 to 199.13 ng/g in surface soil and 300.15 to 555.52 ng/g in surface peat,respectively,both dominated by low molecular weight PAHs(LMW-PAHs),and the distribution line of PAHs in the soil of Shennongjia area is 1500-1700 m.Above 1700 m,PAH concentrations increased with altitude,influenced significantly by TOC and BC,though dependence on BC was stronger than on TOC.However,the dependence of PAHs on BC is higher than TOC.Through soil-air partition coefficient(KSA)and soil fugacity,it is found that the absorption capacity of PAHs is mainly concentrated in Dajiuhu,which is equivalent to a"trap".The ILCRs induced by PAHs in the soil of Shennongjia area are within the safe range.Shennongjia serves as a barrier,preventing pollutant transport from central emission areas to the Tibetan Plateau.Thus,amid tourism development,addressing traffic-related PAH sources,promoting green energy,and controlling air pollutants in central emission areas are vital for ecological protection in Shennongjia and the Tibetan Plateau.展开更多
Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SW...Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SWP,and NG)and three suburban sites(HC,CTV,and YNE)in the Ili River Valley(IRV).For the first time in the IRV,a comprehensive study on 39 PAHs and derivatives was carried out.The results showed that the average∑_(16)PAHs concentration was 130.21±98.94 ng/m^(3),with 16PAHs constituting the dominant fraction(112.51±86.48 ng/m^(3)).The mean BaP and the total BaP equivalent quotient(TEQ)concentrations were 10.28±8.85 ng/m^(3)and 19.74±16.70 ng/m^(3),respectively.Approximately 88%of the daily BaP averages and 98%of the daily TEQ averages exceeded the national daily average standard of BaP(2.5 ng/m^(3)),indicating severe local BaP pollution.Urban sites had notably higher∑PAHs and TEQ concentrations than suburban sites,attributed to increased vehicular traffic and coal combustion in urban areas.PMF results showed that traffic emissions(32.7%-60.5%),coal combustion(13.9%-24.3%)and secondary formation(14.7%-22.7%)were the primary contributors to∑PAHs.Urban sites experienced a greater influence from traffic,while suburban sites were more impacted by coal and biomass burning.On polluted days,traffic sources’contributions increased significantly at HC,YNE,NG and YNCE sites,and secondary formation sources’contributions grew at CTV and YNCE sites.The sourcedependent BaPeq results underscored the role of secondary-formed PAH derivatives in TEQ.展开更多
The Yellow River Delta(YRD)is rich in oil,natural gas,and land resources.With the expansion of an important oil production base in North China,the increased discharge of Polycyclic aromatic hydrocarbons(PAHs)and alkyl...The Yellow River Delta(YRD)is rich in oil,natural gas,and land resources.With the expansion of an important oil production base in North China,the increased discharge of Polycyclic aromatic hydrocarbons(PAHs)and alkylated/nitrated/oxygenated PAHs(APAHs/NPAHs/OPAHs)into the Yellow River poses a potential risk to the aquatic ecosystem and human health.A total of 42 samples were gathered from trunk streams and tributaries within the YRD region during the wet and dry seasons,and 19 PAHs,5 APAHs,16 NPAHs,and 7 OPAHswere measured.The concentrations of ƩPAHs,ƩAPAHs,ƩNPAHs and ƩOPAHs ranged between 29 and 620 ng/L,6.9–81 ng/L,0.64–9.0 ng/L,and 7.2–81 ng/L in water,respectively,and 27–420 ng/g,5.1–130 ng/g,0.19–1.8 ng/g and 3.9–51 ng/g in sediment,respectively.The oil extraction activities resulted in an increased presence of middle-high molecular weight PAHs and APAHs in sediment,and port activities had a notable influence on the proportion of 1-methylpyrene in both water and sediment.The fugacity fraction analysis suggested that sediment was a secondary source of OPAHs,while benzo[k]fluoranthene,benzo[e]pyrene,benzo[a]pyrene,and 5-methylchrysene migrated from water to sediment.The main contributors to PAHs,APAHs,NPAHs,and OPAHs in water and sediment were combustion and petroleum sources.Compared to water,sediment displayed a heightened ecological risk associated with PAHs,APAHs,NPAHs,and OPAHs.Adults residing in the YRD region were at higher risk of cancer than children,which deserves special attention.展开更多
基金supported by Guangdong Basic and Applied Basic Research Foundation(Nos.2021B1515120055 and 2022A1515010499).
文摘Urban rainwater runoff is an important source of nonpoint source pollution due to its transport of diverse contaminants,including polycyclic aromatic hydrocarbons(PAHs)and chlorinated derivatives.Importantly,these chlorinated polycyclic aromatic hydrocarbons(Cl-PAHs)exhibit elevated toxicological potential compared to their non-halogenated parent compounds.In this study,we proposed an approach that combined multivariate receptor model with integration of SHapley Additive exPlanations and Random Forest model.This method identifies the possible sources and reveals the impact of source apportionment results and environmental driving factors(such as geographical and meteorological data)on pollutant concentrations.Sixteen PAHs and nine ClPAHs were detected in 79 runoff samples from all three sites.TheΣ_(16)PAHs average concentration(2923.93 to 6071.83 ng/L)was significantly higher than theΣ_(9)Cl-PAHs(384.34 to 1314.73 ng/L).The source apportionment was conducted by positive matrix factorization(PMF),and six potential pollution sources for PAHs and three for Cl-PAHs were quantified.PAHs primarily originate from the combustion of fossil fuels such as traffic,industrial emissions and coal tar,while Cl-PAHs are mainly derived from atmospheric deposition and industrial emissions.Meanwhile,the self‑organizing map classified PAHs and Cl-PAHs into 2 and 3 groups,respectively.The k-means algorithm yielded 4 clusters for runoff samples.Among machine learning models,Random Forest(RF)demonstrated optimal predictive performance and integrated with SHapley Additive exPlanations(RF-SHAP)revealed the effects of driving factors on the predicted concentration of PAHs and Cl-PAHs in urban runoff samples.
基金supported by the National Key Research and Development Project of China(Nos.2023YFC3709700 and 2024YFC3713800).
文摘Microbial degradation is the primary mechanism for purifying polycyclic aromatic hydrocarbon(PAH)contamination in environments,and biochar immobilization is an effective technology to enhance biodegradation,but the process parameters of the immobilization technology still require further systematic evaluation.Here,biochars derived from pig manure(PM),bamboo(BB),rice straw(RS),and soybean straw(SS)were used as carriers of Mycobacterium sp.ZL7,and the optimal biochar dosage of 1:30(w/V)and immobilization time of 24 h were determined.The immobilization effects followed the order of RS>SS>PM>BB.Scanning electron microscopy and physicochemical properties revealed that porous structures acted as shelters for bacteria,and high nitrogen content,large pore size and high-water holding capacity played important driving roles in immobilization.In the single-substrate system,pyrene removal rates of the PM-,RS-and SS-immobilized materials were greater than 96%,which were significantly higher than those of the biochar alone or the free strain.An orthogonal design experiment in historically PAH-contaminated soil further revealed that,compared with free strains,immobilized materials combined with high moisture content and moderate salicylic acid or Brij 30 can effectively increase the abundance of bacteria and the nidA gene,and enhance the dehydrogenase and polyphenol oxidase activities.The removal rate of total PAHs increased by 8.53%-30.45%after 24 d.Moreover,biochar with strong immobilization capacity showed better PAH removal effects.This study provides a scientific basis and practical reference for biochar-immobilized microorganisms to enhance the self-purification of PAH-contaminated soil.
基金the Department of Science and Technology(DST),Govt.of India for providing funds under the FIST program and PURSE grant vide No.SR/PURSE/2020/31 to the department of Chemistry,University of Kashmir.
文摘This study presents a thorough investigation into the use of single and twin-tailed cationic and anionic surfactant-modified chitosan(SMCS)hydrogel beads as effective adsorbents for the elimination of hazardous polycyclic aromatic hydrocarbons(PAHs)from aqueous solutions.The Chitosan(CS)hydrogel beads were modified with single/twin-tailed anionic surfactants,sodium dodecyl sulfate(SDS)and sodium bis(2-ethylhexyl)sulfosuccinate(AOT),and cationic surfactants,dodecyltrimethylammonium bromide(DTAB)and didodecyldimethylammonium bromide(DDAB),to enhance their adsorption capacity of PAHs.The CS and SMCS beads were evaluated for their structural,mechanical,and adsorption properties using a range of techniques,including infrared spectroscopy(IR),energy-dispersive X-ray spectroscopy(EDX),rheometry,and field emission scanning electron microscopy(FESEM).Adsorption experiments of naphthalene(Nap),acenaphthene(Ace),and phenanthrene(Phe)on SMCS beads demonstrate that they have significantly higher adsorption capacities than CS beads,due to increase in hydrophobic interactions.Adsorption capacity followed the trend,Phen>Ace>Nap for all the beads revealing that twin-tailed SMCS bead possess much higher adsorption capacities(Qmax)compared to single-tailed SMCS beads.For twin tailed surfactants,the maximum adsorption capacities for Nap,Ace and Phe varied as CS-AOT(CS-DDAB):430.0(323.8)611.60(538.18)633.39(536.99)mg/g respectively,outperforming other reported hydrogel beads.The study highlights the simplicity,eco-friendliness,and enhanced performance of surfactant modification for developing high-efficiency adsorbents,paving the way for cost-effective solutions in water re-mediation.
基金supported by the National Natural Science Foundations of China(No.42377235)the National Key Research and Development Program of China(No.2023YFC3709803)+1 种基金the Open Research Fund of Hubei Key Laboratory of Mine Environmental Pollution Control and Remediation(No.2023XZ103)Hubei Polytechnic University talent introduction project(No.24xjz13R).
文摘Studies on the elevation gradient distribution of polycyclic aromatic hydrocarbons(PAHs)have mainly focused on high-altitude regions like the Tibetan Plateau.Investigation of the PAHs distribution in Shennongjia region and the effects of total organic carbon(TOC),black carbon(BC)and elevation gradient on PAHs distribution are of great practical significance for protecting the Tibetan Plateau’s environment.This study collected soil and peat samples across varying vegetation types and altitudes in Shennongjia.Results showed that theΣ16PAHs concentrations ranged from 15.44 to 199.13 ng/g in surface soil and 300.15 to 555.52 ng/g in surface peat,respectively,both dominated by low molecular weight PAHs(LMW-PAHs),and the distribution line of PAHs in the soil of Shennongjia area is 1500-1700 m.Above 1700 m,PAH concentrations increased with altitude,influenced significantly by TOC and BC,though dependence on BC was stronger than on TOC.However,the dependence of PAHs on BC is higher than TOC.Through soil-air partition coefficient(KSA)and soil fugacity,it is found that the absorption capacity of PAHs is mainly concentrated in Dajiuhu,which is equivalent to a"trap".The ILCRs induced by PAHs in the soil of Shennongjia area are within the safe range.Shennongjia serves as a barrier,preventing pollutant transport from central emission areas to the Tibetan Plateau.Thus,amid tourism development,addressing traffic-related PAH sources,promoting green energy,and controlling air pollutants in central emission areas are vital for ecological protection in Shennongjia and the Tibetan Plateau.
基金supported by the National Key R&D Program of China(No.2017YFC0212501)the Fundamental Research Funds for the Central Universities(No.2021YJSMT09)the research project on deep source apportionment of urban air pollution and pollution control strategies in the core area of the Ili River Valley。
文摘Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SWP,and NG)and three suburban sites(HC,CTV,and YNE)in the Ili River Valley(IRV).For the first time in the IRV,a comprehensive study on 39 PAHs and derivatives was carried out.The results showed that the average∑_(16)PAHs concentration was 130.21±98.94 ng/m^(3),with 16PAHs constituting the dominant fraction(112.51±86.48 ng/m^(3)).The mean BaP and the total BaP equivalent quotient(TEQ)concentrations were 10.28±8.85 ng/m^(3)and 19.74±16.70 ng/m^(3),respectively.Approximately 88%of the daily BaP averages and 98%of the daily TEQ averages exceeded the national daily average standard of BaP(2.5 ng/m^(3)),indicating severe local BaP pollution.Urban sites had notably higher∑PAHs and TEQ concentrations than suburban sites,attributed to increased vehicular traffic and coal combustion in urban areas.PMF results showed that traffic emissions(32.7%-60.5%),coal combustion(13.9%-24.3%)and secondary formation(14.7%-22.7%)were the primary contributors to∑PAHs.Urban sites experienced a greater influence from traffic,while suburban sites were more impacted by coal and biomass burning.On polluted days,traffic sources’contributions increased significantly at HC,YNE,NG and YNCE sites,and secondary formation sources’contributions grew at CTV and YNCE sites.The sourcedependent BaPeq results underscored the role of secondary-formed PAH derivatives in TEQ.
基金supported by the Natural Science Foundation of Qingdao(No.23-2-1-224-zyyd-jch).
文摘The Yellow River Delta(YRD)is rich in oil,natural gas,and land resources.With the expansion of an important oil production base in North China,the increased discharge of Polycyclic aromatic hydrocarbons(PAHs)and alkylated/nitrated/oxygenated PAHs(APAHs/NPAHs/OPAHs)into the Yellow River poses a potential risk to the aquatic ecosystem and human health.A total of 42 samples were gathered from trunk streams and tributaries within the YRD region during the wet and dry seasons,and 19 PAHs,5 APAHs,16 NPAHs,and 7 OPAHswere measured.The concentrations of ƩPAHs,ƩAPAHs,ƩNPAHs and ƩOPAHs ranged between 29 and 620 ng/L,6.9–81 ng/L,0.64–9.0 ng/L,and 7.2–81 ng/L in water,respectively,and 27–420 ng/g,5.1–130 ng/g,0.19–1.8 ng/g and 3.9–51 ng/g in sediment,respectively.The oil extraction activities resulted in an increased presence of middle-high molecular weight PAHs and APAHs in sediment,and port activities had a notable influence on the proportion of 1-methylpyrene in both water and sediment.The fugacity fraction analysis suggested that sediment was a secondary source of OPAHs,while benzo[k]fluoranthene,benzo[e]pyrene,benzo[a]pyrene,and 5-methylchrysene migrated from water to sediment.The main contributors to PAHs,APAHs,NPAHs,and OPAHs in water and sediment were combustion and petroleum sources.Compared to water,sediment displayed a heightened ecological risk associated with PAHs,APAHs,NPAHs,and OPAHs.Adults residing in the YRD region were at higher risk of cancer than children,which deserves special attention.
