Polychlorinated biphenyls （PCBs） were measured in atmospheric samples collected from the North Pacific to the Arctic Ocean between July and September 2012 to study the atmospheric concentration characteris-tics of P...Polychlorinated biphenyls （PCBs） were measured in atmospheric samples collected from the North Pacific to the Arctic Ocean between July and September 2012 to study the atmospheric concentration characteris-tics of PCBs and their gas/particle partitioning. The mean concentration of 26 PCBs （vapor plus particulate phase） （∑PCBs） was 19.116 pg/m^3with a standard deviation of 13.833 pg/m^3. Three most abundant conge-ners were CB-28, -52 and -77, accounting for 43.0% to∑PCBs. The predominance of vapor PCBs （79.0% to∑PCBs） in the atmosphere was observed.∑PCBs were negative correlated with the latitudes and inverse of the absolute temperature （1/T）. The significant correlation for most congeners was also observed between the logarithm of gas/particle partition coefficient （logKp） and 1/T. Shallower slopes （from ∑0.15 to ∑0.46, average ∑0.27） were measured from the regression of the logarithm of sub-cooled liquid vapor pressures （logpoL） and logKP for all samples. The difference of the slopes and intercepts among samples was insignifi-cant （p〉0.1）, implying adsorption and/or absorption processes and the aerosol composition did not differ significantly among different samples. By comparing three models, the J-P adsorption model, the octanol/air partition coefficient （KOA） based model and the soot-air model, the gas/particle partitioning of PCBs in the Arctic atmosphere was simulated more precisely by the soot-air model, and the adsorption onto el-emental carbon is more sensitive than the absorption into organic matters of aerosols, especially for low-chlorinated PCB congeners.展开更多
Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of w...Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of which 93 had not been reported in previous studies of museum environments.Many of the detected SVOCs were found to be associated with the chemical agents applied in conservation treatment and the materials used in furnishings.The results of hierarchical cluster analysis(HCA)indicated a spatial variation of SVOCs in the indoor air in the museum,but there were no obvious temporal differences of SVOCs observed in indoor dust.Spearman's correlation analysis showed that several classes of SVOCs were well correlated,suggesting their common sources.Fragrances and plasticizers were found to be the primary sources of SVOC pollution detected in the museum.Compared with compounds in outdoor air,indoor SVOCs had a lower level of unsaturation and more portions of chemically reduced compounds.This study is the first of its kind to comprehensively characterize SVOCs in a museum using an automated NTA approach with GC-Orbitrap-MS.The SVOCs identified in the current study are likely to be present in other similar museums;therefore,further examination of their potential impacts on cultural heritage artifacts,museum personnel,and visitors may be warranted.展开更多
Fire effluents, in most cases, have an adverse effect on human health and the environment. Exposure to some compounds may show both acute and chronic toxicity. There is a lack of knowledge on the effect of organic pro...Fire effluents, in most cases, have an adverse effect on human health and the environment. Exposure to some compounds may show both acute and chronic toxicity. There is a lack of knowledge on the effect of organic products on the human body in terms of the rate of organic material production in fires and their degree of toxicity. Thus, there is a need to expand the scope of studies about the organic products generated from fires and improve the methods of assessment to be included as part of fire hazard assessment. Different factors can be contributed to this lack of knowledge. For example, the composition of organic products generated from fires changes progressively and rapidly with progression of combustion and in a manner that is dependent on the fire condition. It is difficult to identify individual organic compounds produced during combustion. Another key factor is the lack of suitable instruments for measuring organic products generated from a fire. Also, the lack of procedures that are used to evaluate the lethal concentration limits and the lethal dose for a broad range of organic compounds generated from a fire may be another important factor which can be contributed to this lack of knowledge.展开更多
A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith p...A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.展开更多
基金The Chinese Polar Environment Comprehensive Investigation and Assessment Programs under contract Nos 02-01,03-04,04-01 and 04-03the National Natural Science Fundation of China under contract No.21377032
文摘Polychlorinated biphenyls （PCBs） were measured in atmospheric samples collected from the North Pacific to the Arctic Ocean between July and September 2012 to study the atmospheric concentration characteris-tics of PCBs and their gas/particle partitioning. The mean concentration of 26 PCBs （vapor plus particulate phase） （∑PCBs） was 19.116 pg/m^3with a standard deviation of 13.833 pg/m^3. Three most abundant conge-ners were CB-28, -52 and -77, accounting for 43.0% to∑PCBs. The predominance of vapor PCBs （79.0% to∑PCBs） in the atmosphere was observed.∑PCBs were negative correlated with the latitudes and inverse of the absolute temperature （1/T）. The significant correlation for most congeners was also observed between the logarithm of gas/particle partition coefficient （logKp） and 1/T. Shallower slopes （from ∑0.15 to ∑0.46, average ∑0.27） were measured from the regression of the logarithm of sub-cooled liquid vapor pressures （logpoL） and logKP for all samples. The difference of the slopes and intercepts among samples was insignifi-cant （p〉0.1）, implying adsorption and/or absorption processes and the aerosol composition did not differ significantly among different samples. By comparing three models, the J-P adsorption model, the octanol/air partition coefficient （KOA） based model and the soot-air model, the gas/particle partitioning of PCBs in the Arctic atmosphere was simulated more precisely by the soot-air model, and the adsorption onto el-emental carbon is more sensitive than the absorption into organic matters of aerosols, especially for low-chlorinated PCB congeners.
基金supported by the National Key Research and Development Program of China(Grant Nos.2022YFF0606201,2023YFC3806100)。
文摘Non-targeted analysis(NTA)was conducted to identify semi-volatile organic compounds(SVOCs)in a museum in China using the gas chromatography(GC)-Orbitrap-mass spectrometer(MS).Approximately 160 SVOCs were detected,of which 93 had not been reported in previous studies of museum environments.Many of the detected SVOCs were found to be associated with the chemical agents applied in conservation treatment and the materials used in furnishings.The results of hierarchical cluster analysis(HCA)indicated a spatial variation of SVOCs in the indoor air in the museum,but there were no obvious temporal differences of SVOCs observed in indoor dust.Spearman's correlation analysis showed that several classes of SVOCs were well correlated,suggesting their common sources.Fragrances and plasticizers were found to be the primary sources of SVOC pollution detected in the museum.Compared with compounds in outdoor air,indoor SVOCs had a lower level of unsaturation and more portions of chemically reduced compounds.This study is the first of its kind to comprehensively characterize SVOCs in a museum using an automated NTA approach with GC-Orbitrap-MS.The SVOCs identified in the current study are likely to be present in other similar museums;therefore,further examination of their potential impacts on cultural heritage artifacts,museum personnel,and visitors may be warranted.
文摘Fire effluents, in most cases, have an adverse effect on human health and the environment. Exposure to some compounds may show both acute and chronic toxicity. There is a lack of knowledge on the effect of organic products on the human body in terms of the rate of organic material production in fires and their degree of toxicity. Thus, there is a need to expand the scope of studies about the organic products generated from fires and improve the methods of assessment to be included as part of fire hazard assessment. Different factors can be contributed to this lack of knowledge. For example, the composition of organic products generated from fires changes progressively and rapidly with progression of combustion and in a manner that is dependent on the fire condition. It is difficult to identify individual organic compounds produced during combustion. Another key factor is the lack of suitable instruments for measuring organic products generated from a fire. Also, the lack of procedures that are used to evaluate the lethal concentration limits and the lethal dose for a broad range of organic compounds generated from a fire may be another important factor which can be contributed to this lack of knowledge.
基金The authors thank LEAP Technologies(Carrboro,NC,USA)for providing the technical support of the automated solid-phase extraction system.
文摘A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water.
