Mohammed Jaoui, Shawn P Urbanski, Russell W Long, Matthew S Landis
Pine needles represent an important fuel source in coniferous forest systems in the western United States. During forest fires, they can be easily ignited and help sustain flame on the ground. In this study, a comprehensive chemical analysis was conducted to examine oxygenated organic compounds (OOCs) present in PM2.5 formed from burning dry and moist ponderosa pine needles (PPN) in the presence and absence of fine woody debris (FWD). The effect of fuel moisture content (FMC), a key parameter that influence smoke formation, has not received much attention. Therefore, we also investigated the effect of FMC on PM2.5 formation and its composition. Thirty three experiments were conducted at the US Forest Service Fire Science Laboratory. PM2.5 was collected onto 47 mm Teflon filters, and silylated extracts were analyzed by gas chromatography-mass spectrometry. More than fifty OOCs were identified, including levoglucosan and mannosan; n-dodecanoic acid and n-hexadecanoic acid; dihydroabietic acid, and dehydroabietic acid; and a series of intermediate volatile and semivolatile organic compounds. Mass spectra of a wide variety of compounds in electron and chemical ionization mode are provided. Most of these OOCs were identified in this study for the first time in PPN aerosol, although some were previously reported in pine wood and other biomass burning aerosol. Our results show significant changes in the composition and abundance of particles depending on the amount and type of PPN burned. When compared with dry PPN condition, moist PPN showed decreased emissions of PM2.5 and OOCs, due likely to the presence of water in the system that partially suppressed the production of OOCs. Incorporating pine needles in atmospheric models as a contributor to smoke particles generated during forest fires is an essential step towards reducing the current uncertainties regarding the influence of these aerosols on chemical/air mass characteristics, regional meteorology, and the climate.
{"title":"Molecular composition and the impact of fuel moisture content on fresh primary organic aerosol emissions during laboratory combustion of Ponderosa pine needles.","authors":"Mohammed Jaoui, Shawn P Urbanski, Russell W Long, Matthew S Landis","doi":"10.1071/en23013","DOIUrl":"10.1071/en23013","url":null,"abstract":"<p><p>Pine needles represent an important fuel source in coniferous forest systems in the western United States. During forest fires, they can be easily ignited and help sustain flame on the ground. In this study, a comprehensive chemical analysis was conducted to examine oxygenated organic compounds (OOCs) present in PM<sub>2.5</sub> formed from burning dry and moist ponderosa pine needles (PPN) in the presence and absence of fine woody debris (FWD). The effect of fuel moisture content (FMC), a key parameter that influence smoke formation, has not received much attention. Therefore, we also investigated the effect of FMC on PM<sub>2.5</sub> formation and its composition. Thirty three experiments were conducted at the US Forest Service Fire Science Laboratory. PM<sub>2.5</sub> was collected onto 47 mm Teflon filters, and silylated extracts were analyzed by gas chromatography-mass spectrometry. More than fifty OOCs were identified, including levoglucosan and mannosan; n-dodecanoic acid and n-hexadecanoic acid; dihydroabietic acid, and dehydroabietic acid; and a series of intermediate volatile and semivolatile organic compounds. Mass spectra of a wide variety of compounds in electron and chemical ionization mode are provided. Most of these OOCs were identified in this study for the first time in PPN aerosol, although some were previously reported in pine wood and other biomass burning aerosol. Our results show significant changes in the composition and abundance of particles depending on the amount and type of PPN burned. When compared with dry PPN condition, moist PPN showed decreased emissions of PM<sub>2.5</sub> and OOCs, due likely to the presence of water in the system that partially suppressed the production of OOCs. Incorporating pine needles in atmospheric models as a contributor to smoke particles generated during forest fires is an essential step towards reducing the current uncertainties regarding the influence of these aerosols on chemical/air mass characteristics, regional meteorology, and the climate.</p>","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"20 8","pages":"319-338"},"PeriodicalIF":2.0,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11534018/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142582554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chad V. Jarolimek, Josh J. King, Simon C. Apte, Jane Hall, Anil Gautam, Megan Gillmore, Christopher Doyle
Environmental context Metal concentrations can build up to potentially harmful levels in marine mammals as they are at the top of the food chain. This review summarises the information available on metal concentrations in marine mammals, birds and turtles from around Australia. Despite large data gaps, the available data suggest that metal concentrations are similar to those encountered in other regions of the world. Abstract A comprehensive compilation of the published data for trace element concentrations (metals and metalloids) in Australian marine mammals, birds and turtles is presented. The majority of studies have relied on the utilisation of opportunistically collected samples, animal strandings and bycatch. This has resulted in large gaps in geographical, temporal and species coverage data. For instance, little or no data are available for cetaceans in New South Wales or the Northern Territory, and out of 14 endemic species of dolphins, data only exist for seven species. The aforementioned data gaps make it hard to identify statistically significant trends, a problem compounded by data being reported in the form of ranges without raw data. Trace element concentrations measured in various marine species and their tissue types are extremely variable, with ranges typically spanning several orders of magnitude, but are generally comparable with international data. Trends in contaminant concentrations with tissue type follow generally accepted patterns of behaviour for higher organisms, with the highest mercury concentrations in liver and cadmium in kidney tissues. Herbivores have lower contaminant loadings than carnivores, reflecting the importance of diet, and there are identifiable age-related trends for elements such as mercury. The lack of supporting pathology on dead and stranded animals and data on specimens from uncontaminated locations restrict conclusions on organism health impacts. There have been some attempts to use non-invasive sampling of indicator tissues such as fur, bristle and feathers. However, it is currently difficult to extrapolate these data to estimate contaminant concentrations in major organs. Recommendations for future investigations are made.
{"title":"A review of inorganic contaminants in Australian marine mammals, birds and turtles","authors":"Chad V. Jarolimek, Josh J. King, Simon C. Apte, Jane Hall, Anil Gautam, Megan Gillmore, Christopher Doyle","doi":"10.1071/en23057","DOIUrl":"https://doi.org/10.1071/en23057","url":null,"abstract":"Environmental context Metal concentrations can build up to potentially harmful levels in marine mammals as they are at the top of the food chain. This review summarises the information available on metal concentrations in marine mammals, birds and turtles from around Australia. Despite large data gaps, the available data suggest that metal concentrations are similar to those encountered in other regions of the world. Abstract A comprehensive compilation of the published data for trace element concentrations (metals and metalloids) in Australian marine mammals, birds and turtles is presented. The majority of studies have relied on the utilisation of opportunistically collected samples, animal strandings and bycatch. This has resulted in large gaps in geographical, temporal and species coverage data. For instance, little or no data are available for cetaceans in New South Wales or the Northern Territory, and out of 14 endemic species of dolphins, data only exist for seven species. The aforementioned data gaps make it hard to identify statistically significant trends, a problem compounded by data being reported in the form of ranges without raw data. Trace element concentrations measured in various marine species and their tissue types are extremely variable, with ranges typically spanning several orders of magnitude, but are generally comparable with international data. Trends in contaminant concentrations with tissue type follow generally accepted patterns of behaviour for higher organisms, with the highest mercury concentrations in liver and cadmium in kidney tissues. Herbivores have lower contaminant loadings than carnivores, reflecting the importance of diet, and there are identifiable age-related trends for elements such as mercury. The lack of supporting pathology on dead and stranded animals and data on specimens from uncontaminated locations restrict conclusions on organism health impacts. There have been some attempts to use non-invasive sampling of indicator tissues such as fur, bristle and feathers. However, it is currently difficult to extrapolate these data to estimate contaminant concentrations in major organs. Recommendations for future investigations are made.","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135826001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Frédéric Boily, Claude Fortin, Peter G. C. Campbell
Environmental context Thiosulfate is present in natural waters, especially those influenced by sulfide oxidation, and it has a marked affinity for metals such as cadmium. Normally the binding of cadmium by thiosulfate would be expected to reduce the metal’s bioavailability. However, here we demonstrate that algal uptake of cadmium is enhanced in the presence of thiosulfate, indicating that Cd can enter the alga via a novel route as an intact Cd-thiosulfate complex. Rationale For a given free metal ion activity in the exposure solution, the Biotic Ligand Model assumes that metal uptake will be independent of the various ligands present in solution that are buffering [Mz+]. In this context, we have evaluated cadmium bioavailability in the absence or presence of thiosulfate, using Chlamydomonas reinhardtii as the test alga. Methodology Short-term exposures (≤41 min) were run with a fixed concentration of the free Cd2+ ion (3.0 ± 0.1 nM), buffered with either nitrilotriacetate or thiosulfate, to determine Cd uptake. Subsequent long-term exposures (72 h) over a range of free Cd2+ concentrations were used to determine the effects of Cd on algal growth. Results Contrary to Biotic Ligand Model predictions, Cd uptake was enhanced when Cd2+ was buffered with thiosulfate. Removal of sulfate from this exposure medium increased Cd uptake; conversely, if [SO42−] was increased, Cd uptake decreased. In the absence of thiosulfate, Cd uptake was unaffected by changes in [SO42−]. In the long-term exposures, the cellular Cd quota needed to reduce algal growth by 50% was significantly higher in the presence of thiosulfate than in its absence. Discussion In the presence of thiosulfate, Cd can enter the algal cell not only by cation transport but also by transport of the intact Cd-thiosulfate complex via the anion transporter responsible for sulfate uptake. We speculate that some of the Cd taken up by anion transport remains in complexed form and is less bioavailable than the Cd that enters the cell via cation transport.
{"title":"<i>Corrigendum to</i>: Cadmium thiosulfate complexes can be assimilated by a green alga via a sulfate transporter but do not increase Cd toxicity","authors":"Frédéric Boily, Claude Fortin, Peter G. C. Campbell","doi":"10.1071/en22038_co","DOIUrl":"https://doi.org/10.1071/en22038_co","url":null,"abstract":"<sec> Environmental context Thiosulfate is present in natural waters, especially those influenced by sulfide oxidation, and it has a marked affinity for metals such as cadmium. Normally the binding of cadmium by thiosulfate would be expected to reduce the metal&#x2019;s bioavailability. However, here we demonstrate that algal uptake of cadmium is enhanced in the presence of thiosulfate, indicating that Cd can enter the alga via a novel route as an intact Cd-thiosulfate complex. </sec> <sec> Rationale For a given free metal ion activity in the exposure solution, the Biotic Ligand Model assumes that metal uptake will be independent of the various ligands present in solution that are buffering [M<sup><i>z</i>+</sup>]. In this context, we have evaluated cadmium bioavailability in the absence or presence of thiosulfate, using <i>Chlamydomonas reinhardtii</i> as the test alga. </sec> <sec> Methodology Short-term exposures (&#x2264;41&#x2009;min) were run with a fixed concentration of the free Cd<sup>2+</sup> ion (3.0&#x2009;&#xb1;&#x2009;0.1&#x2009;nM), buffered with either nitrilotriacetate or thiosulfate, to determine Cd uptake. Subsequent long-term exposures (72&#x2009;h) over a range of free Cd<sup>2+</sup> concentrations were used to determine the effects of Cd on algal growth. </sec> <sec> Results Contrary to Biotic Ligand Model predictions, Cd uptake was enhanced when Cd<sup>2+</sup> was buffered with thiosulfate. Removal of sulfate from this exposure medium increased Cd uptake; conversely, if [SO<sub>4</sub><sup>2&#x2212;</sup>] was increased, Cd uptake decreased. In the absence of thiosulfate, Cd uptake was unaffected by changes in [SO<sub>4</sub><sup>2&#x2212;</sup>]. In the long-term exposures, the cellular Cd quota needed to reduce algal growth by 50% was significantly higher in the presence of thiosulfate than in its absence. </sec> <sec> Discussion In the presence of thiosulfate, Cd can enter the algal cell not only by cation transport but also by transport of the intact Cd-thiosulfate complex via the anion transporter responsible for sulfate uptake. We speculate that some of the Cd taken up by anion transport remains in complexed form and is less bioavailable than the Cd that enters the cell via cation transport. </sec>","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136177858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Environmental context Thiosulfate is present in natural waters, especially those influenced by sulfide oxidation, and it has a marked affinity for metals such as cadmium. Normally the binding of cadmium by thiosulfate would be expected to reduce the metal’s bioavailability. However, here we demonstrate that algal uptake of cadmium is enhanced in the presence of thiosulfate, indicating that Cd can enter the alga via a novel route as an intact Cd-thiosulfate complex. Rationale For a given free metal ion activity in the exposure solution, the Biotic Ligand Model assumes that metal uptake will be independent of the various ligands present in solution that are buffering [Mz+]. In this context, we have evaluated cadmium bioavailability in the absence or presence of thiosulfate, using Chlamydomonas reinhardtii as the test alga. Methodology Short-term exposures (≤41 min) were run with a fixed concentration of the free Cd2+ ion (3.0 ± 0.1 nM), buffered with either nitrilotriacetate or thiosulfate, to determine Cd uptake. Subsequent long-term exposures (72 h) over a range of free Cd2+ concentrations were used to determine the effects of Cd on algal growth. Results Contrary to Biotic Ligand Model predictions, Cd uptake was enhanced when Cd2+ was buffered with thiosulfate. Removal of sulfate from this exposure medium increased Cd uptake; conversely, if [SO42−] was increased, Cd uptake decreased. In the absence of thiosulfate, Cd uptake was unaffected by changes in [SO42−]. In the long-term exposures, the cellular Cd quota needed to reduce algal growth by 50% was significantly higher in the presence of thiosulfate than in its absence. Discussion In the presence of thiosulfate, Cd can enter the algal cell not only by cation transport but also by transport of the intact Cd-thiosulfate complex via the anion transporter responsible for sulfate uptake. We speculate that some of the Cd taken up by anion transport remains in complexed form and is less bioavailable than the Cd that enters the cell via cation transport.
{"title":"Cadmium thiosulfate complexes can be assimilated by a green alga via a sulfate transporter but do not increase Cd toxicity","authors":"Frédéric Boily, C. Fortin, P. Campbell","doi":"10.1071/en22038","DOIUrl":"https://doi.org/10.1071/en22038","url":null,"abstract":"<sec> Environmental context Thiosulfate is present in natural waters, especially those influenced by sulfide oxidation, and it has a marked affinity for metals such as cadmium. Normally the binding of cadmium by thiosulfate would be expected to reduce the metal’s bioavailability. However, here we demonstrate that algal uptake of cadmium is enhanced in the presence of thiosulfate, indicating that Cd can enter the alga via a novel route as an intact Cd-thiosulfate complex. </sec> <sec> Rationale For a given free metal ion activity in the exposure solution, the Biotic Ligand Model assumes that metal uptake will be independent of the various ligands present in solution that are buffering [M<sup><i>z</i>+</sup>]. In this context, we have evaluated cadmium bioavailability in the absence or presence of thiosulfate, using <i>Chlamydomonas reinhardtii</i> as the test alga. </sec> <sec> Methodology Short-term exposures (≤41 min) were run with a fixed concentration of the free Cd<sup>2+</sup> ion (3.0 ± 0.1 nM), buffered with either nitrilotriacetate or thiosulfate, to determine Cd uptake. Subsequent long-term exposures (72 h) over a range of free Cd<sup>2+</sup> concentrations were used to determine the effects of Cd on algal growth. </sec> <sec> Results Contrary to Biotic Ligand Model predictions, Cd uptake was enhanced when Cd<sup>2+</sup> was buffered with thiosulfate. Removal of sulfate from this exposure medium increased Cd uptake; conversely, if [SO<sub>4</sub><sup>2−</sup>] was increased, Cd uptake decreased. In the absence of thiosulfate, Cd uptake was unaffected by changes in [SO<sub>4</sub><sup>2−</sup>]. In the long-term exposures, the cellular Cd quota needed to reduce algal growth by 50% was significantly higher in the presence of thiosulfate than in its absence. </sec> <sec> Discussion In the presence of thiosulfate, Cd can enter the algal cell not only by cation transport but also by transport of the intact Cd-thiosulfate complex via the anion transporter responsible for sulfate uptake. We speculate that some of the Cd taken up by anion transport remains in complexed form and is less bioavailable than the Cd that enters the cell via cation transport. </sec>","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"18 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90510173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"<i>Corrigendum to</i>: Dedication to Professor Kevin Francesconi, father of organoarsenicals in the environment","authors":"Joerg Feldmann","doi":"10.1071/en23040_co","DOIUrl":"https://doi.org/10.1071/en23040_co","url":null,"abstract":"","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"7 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136178100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Environmental context With the rapid pace of industrialisation and urbanisation, soil contamination by organic pollutants has become a global focus of concern due to its serious threat to ecosystems and human health. Although a myriad of synthetic catalysts have been developed, natural minerals have the potential to be developed into cost-effective, environmentally benign and efficient catalysts to decontaminate soil. The efficient performance of natural minerals demonstrated in this study indicates a potential for their utilisation in the removal of refractory organic pollutants in soil. Rationale Organic pollution of soil has raised worldwide concern owing to the potential effects on ecosystems and human health. Natural metal minerals rich in transition metal elements have the potential to be developed into environmentally benign activators of peroxymonosulfate (PMS) and hydrogen peroxide (H2O2) for soil decontamination. Methodology A comparison study employing natural chalcopyrite (NCP) and natural pyrite (NP) as activators in the combined Fenton-like systems of PMS and H2O2 to degrade organic pollutants in soil has been carried out. Tetracycline hydrochloride (TCH) and phenanthrene (PHE) were selected as representatives of widely existing contaminants, antibiotics and polycyclic aromatic hydrocarbons, in the study. Key parameters including initial pH, catalyst and oxidants dosage were also optimised. Results A total organic carbon (TOC) removal efficiency of 68.66% was achieved for TCH (500 mg kg–1) with the addition of 0.75 g L–1 NCP, 1.23 mM PMS and 1.23 mM H2O2 within 4 h, whereas a slightly lower mineralisation efficiency of 64.78% was obtained by the NP heterogeneous system. For PHE (50 mg kg–1), 93.04% of TOC was removed using a NCP/PMS/H2O2 process, which was much higher than that of NP (45.76%) after 24 h. The quenching experiments indicated that ˙OH prevailed over SO4˙−EN22116_IE1.gif, and ˙O2−EN22116_IE2.gif also played a vital role in the PMS/H2O2 coupling process. Discussion The more superior performance of NCP has been elucidated via X-ray photoelectron spectroscoy analysis and comparison of catalytic mechanisms. The existence of Cu+ played an important role in the transformation of Fe3+ to Fe2+ and facilitated the continuous generation of active radicals. A possible degradation pathway was proposed based on the intermediates identified by GC-MS analysis. We anticipate this study would provide implications for the utilisation of natural minerals in the removal of refractory organic pollutants in soil.
随着工业化和城市化进程的加快,土壤有机污染物污染严重威胁着生态系统和人类健康,已成为全球关注的焦点。虽然已经开发了无数的合成催化剂,但天然矿物有潜力开发成具有成本效益、环境友好和有效的土壤净化催化剂。本研究证明的天然矿物质的高效性能表明它们在去除土壤中难降解有机污染物方面具有潜力。土壤有机污染由于对生态系统和人类健康的潜在影响而引起了全世界的关注。富含过渡金属元素的天然金属矿物具有开发成环境友好型过氧单硫酸盐(PMS)和过氧化氢(H2O2)土壤净化活化剂的潜力。方法采用天然黄铜矿(NCP)和天然黄铁矿(NP)作为活化剂,在PMS和H2O2联合fenton类体系中降解土壤中有机污染物进行了对比研究。选择盐酸四环素(TCH)和菲(PHE)作为广泛存在的污染物、抗生素和多环芳烃的代表。对初始pH、催化剂和氧化剂投加量等关键参数进行了优化。结果在添加0.75 g L-1 NCP、1.23 mM PMS和1.23 mM H2O2的条件下,TCH (500 mg kg-1)在4 h内的总有机碳(TOC)去除率为68.66%,而NP非均相体系的矿化效率略低,为64.78%。对于PHE (50 mg kg-1),采用NCP/PMS/H2O2工艺,24 h后TOC去除率为93.04%,远高于NP(45.76%)。淬灭实验表明,˙OH优于SO4˙EN22116_IE1.gif,˙O2−EN22116_IE2.gif在PMS/H2O2耦合过程中也起重要作用。通过x射线光电子能谱分析和催化机理比较,阐明了NCP更优越的性能。Cu+的存在对Fe3+向Fe2+的转变起着重要的作用,促进了活性自由基的不断生成。基于GC-MS鉴定的中间体,提出了一种可能的降解途径。我们预计这项研究将为利用天然矿物质去除土壤中难降解的有机污染物提供启示。
{"title":"Soil decontamination by natural minerals: a comparison study of chalcopyrite and pyrite","authors":"Yanhua Wu, Yuchan Li, Hong Wang","doi":"10.1071/en22116","DOIUrl":"https://doi.org/10.1071/en22116","url":null,"abstract":"Environmental context With the rapid pace of industrialisation and urbanisation, soil contamination by organic pollutants has become a global focus of concern due to its serious threat to ecosystems and human health. Although a myriad of synthetic catalysts have been developed, natural minerals have the potential to be developed into cost-effective, environmentally benign and efficient catalysts to decontaminate soil. The efficient performance of natural minerals demonstrated in this study indicates a potential for their utilisation in the removal of refractory organic pollutants in soil. Rationale Organic pollution of soil has raised worldwide concern owing to the potential effects on ecosystems and human health. Natural metal minerals rich in transition metal elements have the potential to be developed into environmentally benign activators of peroxymonosulfate (PMS) and hydrogen peroxide (H2O2) for soil decontamination. Methodology A comparison study employing natural chalcopyrite (NCP) and natural pyrite (NP) as activators in the combined Fenton-like systems of PMS and H2O2 to degrade organic pollutants in soil has been carried out. Tetracycline hydrochloride (TCH) and phenanthrene (PHE) were selected as representatives of widely existing contaminants, antibiotics and polycyclic aromatic hydrocarbons, in the study. Key parameters including initial pH, catalyst and oxidants dosage were also optimised. Results A total organic carbon (TOC) removal efficiency of 68.66% was achieved for TCH (500 mg kg–1) with the addition of 0.75 g L–1 NCP, 1.23 mM PMS and 1.23 mM H2O2 within 4 h, whereas a slightly lower mineralisation efficiency of 64.78% was obtained by the NP heterogeneous system. For PHE (50 mg kg–1), 93.04% of TOC was removed using a NCP/PMS/H2O2 process, which was much higher than that of NP (45.76%) after 24 h. The quenching experiments indicated that ˙OH prevailed over SO4˙−EN22116_IE1.gif, and ˙O2−EN22116_IE2.gif also played a vital role in the PMS/H2O2 coupling process. Discussion The more superior performance of NCP has been elucidated via X-ray photoelectron spectroscoy analysis and comparison of catalytic mechanisms. The existence of Cu+ played an important role in the transformation of Fe3+ to Fe2+ and facilitated the continuous generation of active radicals. A possible degradation pathway was proposed based on the intermediates identified by GC-MS analysis. We anticipate this study would provide implications for the utilisation of natural minerals in the removal of refractory organic pollutants in soil.","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"32 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72508893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Environmental context Mosses and lichens are widely distributed in montane forests and their important role in global biogeochemical cycles has been increasingly recognised. This study of mercury accumulation and sources in mosses and lichens, using mercury isotopic data, provides evidence that they promote atmospheric mercury deposition in these forests, which is an important function that should be incorporated into current mercury mass balance budgets for forests. Rationale Mosses and lichens, which are widely distributed in montane forests, are often used to monitor the atmospheric mercury (Hg) depositions. In this study we hypothesised that atmospheric Hg uptake by mosses and lichens could greatly promote Hg depositions in montane forests. Methodology We comprehensively determined the Hg concentration and isotopic signatures of various species of mosses and lichens in a subtropical montane forest, to quantify the Hg accumulation, influencing factors and potential Hg depositions induced by mosses and lichens. Results Our results show that the higher Hg concentrations in mosses than in lichens are mainly due to their species-specific, morphological and physiological differences. Hg isotopic mixing model results display that uptake of atmospheric elemental Hg (Hg0) contributes 89.2 ± 22.8% of Hg in mosses and 88.4 ± 24.4% in lichens. The lichens growing on trees have a lower atmospheric Hg0 source contribution than on the ground (61.3 ± 42.5% versus 93.6 ± 10.0%) because of the elevated rainfall Hg uptake on trees. The Hg storage in live moss and lichen is 28.0 ± 16.5 and 0.9 ± 1.0 μg m−2, respectively. Given the 1–2-year lifespan of moss, the moss induced atmospheric Hg deposition is almost equivalent to litterfall Hg deposition which was previously used as a proxy for atmospheric Hg0 deposition in forests. Discussion Overall, we suggest mosses and lichens play an important role in atmospheric Hg depositions and recommend more research in montane forests.
{"title":"Mosses and lichens enhance atmospheric elemental mercury deposition in a subtropical montane forest†","authors":"Xin Li, Xun Wang, Hui Zhang, Zhiyun Lu","doi":"10.1071/en22124","DOIUrl":"https://doi.org/10.1071/en22124","url":null,"abstract":"Environmental context Mosses and lichens are widely distributed in montane forests and their important role in global biogeochemical cycles has been increasingly recognised. This study of mercury accumulation and sources in mosses and lichens, using mercury isotopic data, provides evidence that they promote atmospheric mercury deposition in these forests, which is an important function that should be incorporated into current mercury mass balance budgets for forests. Rationale Mosses and lichens, which are widely distributed in montane forests, are often used to monitor the atmospheric mercury (Hg) depositions. In this study we hypothesised that atmospheric Hg uptake by mosses and lichens could greatly promote Hg depositions in montane forests. Methodology We comprehensively determined the Hg concentration and isotopic signatures of various species of mosses and lichens in a subtropical montane forest, to quantify the Hg accumulation, influencing factors and potential Hg depositions induced by mosses and lichens. Results Our results show that the higher Hg concentrations in mosses than in lichens are mainly due to their species-specific, morphological and physiological differences. Hg isotopic mixing model results display that uptake of atmospheric elemental Hg (Hg0) contributes 89.2 ± 22.8% of Hg in mosses and 88.4 ± 24.4% in lichens. The lichens growing on trees have a lower atmospheric Hg0 source contribution than on the ground (61.3 ± 42.5% versus 93.6 ± 10.0%) because of the elevated rainfall Hg uptake on trees. The Hg storage in live moss and lichen is 28.0 ± 16.5 and 0.9 ± 1.0 μg m−2, respectively. Given the 1–2-year lifespan of moss, the moss induced atmospheric Hg deposition is almost equivalent to litterfall Hg deposition which was previously used as a proxy for atmospheric Hg0 deposition in forests. Discussion Overall, we suggest mosses and lichens play an important role in atmospheric Hg depositions and recommend more research in montane forests.","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"45 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80713575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Environmental context Elemental selenium plays an important role in maintaining human health and the growth of plants and animals. We studied the availability of selenium in soils and agricultural crops in Guiyang City, China, and found that the soil is selenium-rich and the crops are selenium-enriched. These results can help to understand and improve the development of mountain agriculture and rural revitalisation. Rationale Selenium (Se) is a critical element for both maintaining human health and the growth of plants and animals. The content of Se in crops is primarily determined by its speciation in soil. Therefore, the investigation of soil Se and its speciation has become a key focus of current research. Methodology In this study, taking a typical seleniferous area in Guiyang City as the study area, we investigated selenium speciation in Se-rich soil and its distribution characteristics in both soil and crops using atomic fluorescence spectroscopy (AFS) and a five-step extraction processing methods. Moreover, we further explored the key factors that affect the distribution of Se in soil. Results The findings are summarised as follows: (1) the Se content in all investigated samples met the standards of selenium-rich soil (0.40 mg/kg). The Se content in the soil surrounding crop roots ranged from 0.96 to 4.29 mg/kg, with an average value of 2.18 mg/kg. (2) Soil Se primarily existed in organic, residual, and iron and manganese oxide-binding species. The organic, sulfide-binding, and elemental Se species were the major contributors, accounting for an average of 47.00%, while the content of water-soluble, exchangeable, and carbonate-binding Se species was significantly lower. (3) Almost all crops, regardless of their types, were found Se-enriched, accounting for approximately 89.47% of the total crops in the study area. The average Se content was 0.35, 0.12, and 0.026 mg/kg in tea, rice, and corn, respectively. Discussion Varying soil physical–chemical properties, such as the content of soil organic matter content and pH levels, etc. can impact the distribution of Se in soil differently. These findings can serve as a scientific foundation for the effective utilisation of selenium-rich land resources in Guiyang city. They can also support and facilitate the development of modern specialty and high-efficiency mountain agriculture, ultimately contributing to rural revitalisation and the national implementation of the Big Ecology Strategy.
{"title":"Selenium speciation and characteristics of selenium-enriched crops in Guiyang seleniferous soil, southwestern China","authors":"Z. Pan, Ju Chen, Minzi Wang, Yanfei Feng, W. Meng","doi":"10.1071/en22084","DOIUrl":"https://doi.org/10.1071/en22084","url":null,"abstract":"Environmental context Elemental selenium plays an important role in maintaining human health and the growth of plants and animals. We studied the availability of selenium in soils and agricultural crops in Guiyang City, China, and found that the soil is selenium-rich and the crops are selenium-enriched. These results can help to understand and improve the development of mountain agriculture and rural revitalisation. Rationale Selenium (Se) is a critical element for both maintaining human health and the growth of plants and animals. The content of Se in crops is primarily determined by its speciation in soil. Therefore, the investigation of soil Se and its speciation has become a key focus of current research. Methodology In this study, taking a typical seleniferous area in Guiyang City as the study area, we investigated selenium speciation in Se-rich soil and its distribution characteristics in both soil and crops using atomic fluorescence spectroscopy (AFS) and a five-step extraction processing methods. Moreover, we further explored the key factors that affect the distribution of Se in soil. Results The findings are summarised as follows: (1) the Se content in all investigated samples met the standards of selenium-rich soil (0.40 mg/kg). The Se content in the soil surrounding crop roots ranged from 0.96 to 4.29 mg/kg, with an average value of 2.18 mg/kg. (2) Soil Se primarily existed in organic, residual, and iron and manganese oxide-binding species. The organic, sulfide-binding, and elemental Se species were the major contributors, accounting for an average of 47.00%, while the content of water-soluble, exchangeable, and carbonate-binding Se species was significantly lower. (3) Almost all crops, regardless of their types, were found Se-enriched, accounting for approximately 89.47% of the total crops in the study area. The average Se content was 0.35, 0.12, and 0.026 mg/kg in tea, rice, and corn, respectively. Discussion Varying soil physical–chemical properties, such as the content of soil organic matter content and pH levels, etc. can impact the distribution of Se in soil differently. These findings can serve as a scientific foundation for the effective utilisation of selenium-rich land resources in Guiyang city. They can also support and facilitate the development of modern specialty and high-efficiency mountain agriculture, ultimately contributing to rural revitalisation and the national implementation of the Big Ecology Strategy.","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"326 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77196550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Environmental context Naturally occurring arsenic was the likely cause of endemic black foot disease in groundwaters in Taiwan, and levels still exceed Taiwan EPA water quality standards. A method for the clean-up of these groundwaters that is both feasible and environmentally friendly is urgently needed. Oxidation of As(III) as H3AsO3 to the less toxic As(V)− and removal of As in groundwater was performed quantitatively by electrosorption using materials derived from agricultural wastes; this shows that this method has the potential to be a novel, green remediation method. Rationale Naturally occurring arsenic in the groundwater caused black-foot disease (BFD) in the 1950s on the southwest seashore of Taiwan. Recently, we found that the concentration of arsenic in groundwater taken from currently sealed wells in areas previously affected by BFD remained higher than the Taiwan (EPA) water quality standard. Although clean tap water is available in that area, removal of arsenic from the groundwater is of great importance to expand possible utilisation. Methodology Removal of arsenic from two old endemic BFD groundwaters with activated carbon (AC) electrodes recycled from agricultural wastes by electrosorption using capacitive deionisation (CDI) processes was studied. A better understanding of arsenic electrochemistry involved in electrosorption was investigated by in situ X-ray absorption near-edge structure spectroscopy. Results Arsenic removal efficiencies (61–93%) remained high across concentrations (5 and 196 mg/L). A high oxidation rate constant (0.93 h−1) for As(III)0 to As(V)− was found, allowing the electrosorption of As(V)− onto the meso- and micro-pores of the AC CDI electrodes with rate constants of 0.021 and 0.0013 h−1, respectively. Removal of arsenic from contaminated groundwater for drinking water was achieved with six CDI reactors in series. Moreover, in the presence of other ions (such as Na+, Mg2+ and Ca2+), 60–73% of As(III)0 and As(V)− ions were removed from the groundwaters by electrosorption. Discussion We have developed an engineering-feasible method for converting As(III)0 to less toxic As(V)−, enabling its removal by electrosorption, which demonstrates the feasibility for green remediation of BFD waters as well as other arsenic-contaminated groundwaters.
{"title":"Removal of toxic arsenic(iii) from an old endemic black-foot disease groundwater by oxidative electrosorption","authors":"P.-A. Chen, C. Peng, S.-H. Liu, H. -. Wang","doi":"10.1071/en23001","DOIUrl":"https://doi.org/10.1071/en23001","url":null,"abstract":"Environmental context Naturally occurring arsenic was the likely cause of endemic black foot disease in groundwaters in Taiwan, and levels still exceed Taiwan EPA water quality standards. A method for the clean-up of these groundwaters that is both feasible and environmentally friendly is urgently needed. Oxidation of As(III) as H3AsO3 to the less toxic As(V)− and removal of As in groundwater was performed quantitatively by electrosorption using materials derived from agricultural wastes; this shows that this method has the potential to be a novel, green remediation method. Rationale Naturally occurring arsenic in the groundwater caused black-foot disease (BFD) in the 1950s on the southwest seashore of Taiwan. Recently, we found that the concentration of arsenic in groundwater taken from currently sealed wells in areas previously affected by BFD remained higher than the Taiwan (EPA) water quality standard. Although clean tap water is available in that area, removal of arsenic from the groundwater is of great importance to expand possible utilisation. Methodology Removal of arsenic from two old endemic BFD groundwaters with activated carbon (AC) electrodes recycled from agricultural wastes by electrosorption using capacitive deionisation (CDI) processes was studied. A better understanding of arsenic electrochemistry involved in electrosorption was investigated by in situ X-ray absorption near-edge structure spectroscopy. Results Arsenic removal efficiencies (61–93%) remained high across concentrations (5 and 196 mg/L). A high oxidation rate constant (0.93 h−1) for As(III)0 to As(V)− was found, allowing the electrosorption of As(V)− onto the meso- and micro-pores of the AC CDI electrodes with rate constants of 0.021 and 0.0013 h−1, respectively. Removal of arsenic from contaminated groundwater for drinking water was achieved with six CDI reactors in series. Moreover, in the presence of other ions (such as Na+, Mg2+ and Ca2+), 60–73% of As(III)0 and As(V)− ions were removed from the groundwaters by electrosorption. Discussion We have developed an engineering-feasible method for converting As(III)0 to less toxic As(V)−, enabling its removal by electrosorption, which demonstrates the feasibility for green remediation of BFD waters as well as other arsenic-contaminated groundwaters.","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"47 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2023-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86025454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dedication to Professor Kevin Francesconi, father of organoarsenicals in the environment","authors":"J. Feldmann","doi":"10.1071/en23040","DOIUrl":"https://doi.org/10.1071/en23040","url":null,"abstract":"","PeriodicalId":11714,"journal":{"name":"Environmental Chemistry","volume":"92 4 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2023-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83671493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}