Pub Date : 2024-04-28DOI: 10.1016/j.jes.2024.04.031
Zihan Shu , Hailan Yang , Shujing Ye , Hong Li , Zhiming Yang , Chuang Li , Xiaofei Tan , Shaobo Liu , Hou Wang
P-arsanilic acid (AA) has received widespread attention because of its conversion to more toxic inorganic arsenic compounds (arsenate and arsenite) in the natural ecosystems. Its removal process and mechanisms with co-existence of microplastics remain unkown. In this study, biochar loaded with nano zero-valent iron (nZVI) particles (ISBC) was prepared by using iron scrap obtained from a steel works and wood chips collected from a wood processing plant. The advanced oxidation system of sodium persulfate (PDS) activated by ISBC was applied for AA degradation and inorganic arsenic control in aqueous media. More than 99% of the AA was completely degraded by the ISBC/PDS system, and the As(III) on AA was almost completely oxidized to As(V) and finally removed by ISBC. HCO3− inhibited the removal of AA by the ISBC/PDS system, while Cl− had a dual effect that showing inhibition at low concentrations yet promotion at high concentrations. The effect of microplastics on the degradation of AA by the ISBC/PDS system was further investigated due to the potential for combined microplastic and organic arsenic contamination in rural/remote areas. Microplastics were found to have little effect on AA degradation in the ISBC/PDS system, while affect the transport of inorganic arsenic generated from AA degradation. Overall, this study provides new insights and methods for efficient removal of p-arsanilic acid from water with coexisting microplastics.
对胂酸(AA)之所以受到广泛关注,是因为它在自然生态系统中会转化为毒性更强的无机砷化合物(砷酸盐和亚砷酸盐)。其去除过程以及与微塑料共存的机制仍不清楚。在这项研究中,利用从钢铁厂获得的废铁和从木材加工厂收集的木屑,制备了负载纳米零价铁(nZVI)颗粒(ISBC)的生物炭。由 ISBC 激活的过硫酸钠(PDS)高级氧化系统被用于降解 AA 和控制水介质中的无机砷。超过 99% 的 AA 被 ISBC/PDS 系统完全降解,AA 上的 As(III) 几乎完全氧化为 As(V),并最终被 ISBC 去除。HCO3- 抑制了 ISBC/PDS 系统对 AA 的去除,而 Cl- 则具有双重效应,低浓度时有抑制作用,高浓度时有促进作用。由于农村/偏远地区可能同时受到微塑料和有机砷的污染,我们进一步研究了微塑料对 ISBC/PDS 系统降解 AA 的影响。研究发现,微塑料对 ISBC/PDS 系统中的 AA 降解影响不大,但会影响 AA 降解产生的无机砷的迁移。总之,这项研究为高效去除水中共存的微塑料中的对氨基苯甲酸提供了新的见解和方法。
{"title":"Iron scrap derived nano zero-valent iron/biochar activated persulfate for p-arsanilic acid decontamination with coexisting microplastics","authors":"Zihan Shu , Hailan Yang , Shujing Ye , Hong Li , Zhiming Yang , Chuang Li , Xiaofei Tan , Shaobo Liu , Hou Wang","doi":"10.1016/j.jes.2024.04.031","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.031","url":null,"abstract":"<div><p>P-arsanilic acid (AA) has received widespread attention because of its conversion to more toxic inorganic arsenic compounds (arsenate and arsenite) in the natural ecosystems. Its removal process and mechanisms with co-existence of microplastics remain unkown. In this study, biochar loaded with nano zero-valent iron (nZVI) particles (ISBC) was prepared by using iron scrap obtained from a steel works and wood chips collected from a wood processing plant. The advanced oxidation system of sodium persulfate (PDS) activated by ISBC was applied for AA degradation and inorganic arsenic control in aqueous media. More than 99% of the AA was completely degraded by the ISBC/PDS system, and the As(III) on AA was almost completely oxidized to As(V) and finally removed by ISBC. HCO<sub>3</sub><sup>−</sup> inhibited the removal of AA by the ISBC/PDS system, while Cl<sup>−</sup> had a dual effect that showing inhibition at low concentrations yet promotion at high concentrations. The effect of microplastics on the degradation of AA by the ISBC/PDS system was further investigated due to the potential for combined microplastic and organic arsenic contamination in rural/remote areas. Microplastics were found to have little effect on AA degradation in the ISBC/PDS system, while affect the transport of inorganic arsenic generated from AA degradation. Overall, this study provides new insights and methods for efficient removal of p-arsanilic acid from water with coexisting microplastics.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141067334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-27DOI: 10.1016/j.jes.2024.04.025
Jinyan Xiao, Chi Zhang, Lei Yang, Shengwei Tang, Wenxiang Tang
It is still a challenge to develop hierarchically nanostructured catalysts with simple approaches to enhance the low-temperature catalytic activity. Herein, a set of mesoporous Co-Cu binary metal oxides with different morphologies were successfully prepared via a facile ammonium bicarbonate precipitation method without any templates or surfactants, which were further applied for catalytic removal of carcinogenic toluene. Among the catalysts with different ratios, the CoCu0.2 composite oxide presented the best performance, where the temperature required for 90% conversion of toluene was only 237°C at the high weight hour space velocity (WHSV) of 240,000 mL/(gcat·hr). Meanwhile, compared to the related Co-Cu composite oxides prepared by using different precipitants (NaOH and H2C2O4), the NH4HCO3-derived CoCu0.2 sample exhibited better catalytic efficiency in toluene oxidation, while the T90 were 22 and 28°C lower than those samples prepared by NaOH and H2C2O4 routes, respectively. Based on various characterizations, it could be deduced that the excellent performance was related to the small crystal size (6.7 nm), large specific surface area (77.0 m2/g), hollow hierarchical nanostructure with abundant high valence Co ions and adsorbed oxygen species. In situ DRIFTS further revealed that the possible reaction pathway for the toluene oxidation over CoCu0.2 catalyst followed the route of absorbed toluene → benzyl alcohol → benzaldehyde → benzoic acid → carbonate → CO2 and H2O. In addition, CoCu0.2 sample could keep stable with long-time operation and occur little inactivation under humid condition (5 vol.% water), which revealed that the NH4HCO3-derived CoCu0.2 nanocatalyst possessed great potential in industrial applications for VOCs abatement.
{"title":"Extraordinary synergy on 3D hierarchical porous Co-Cu nanocomposite for catalytic elimination of VOCs at low temperature and high space velocity","authors":"Jinyan Xiao, Chi Zhang, Lei Yang, Shengwei Tang, Wenxiang Tang","doi":"10.1016/j.jes.2024.04.025","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.025","url":null,"abstract":"<div><p>It is still a challenge to develop hierarchically nanostructured catalysts with simple approaches to enhance the low-temperature catalytic activity. Herein, a set of mesoporous Co-Cu binary metal oxides with different morphologies were successfully prepared via a facile ammonium bicarbonate precipitation method without any templates or surfactants, which were further applied for catalytic removal of carcinogenic toluene. Among the catalysts with different ratios, the CoCu<sub>0.2</sub> composite oxide presented the best performance, where the temperature required for 90% conversion of toluene was only 237°C at the high weight hour space velocity (WHSV) of 240,000 mL/(g<sub>cat</sub>·hr). Meanwhile, compared to the related Co-Cu composite oxides prepared by using different precipitants (NaOH and H<sub>2</sub>C<sub>2</sub>O<sub>4</sub>), the NH<sub>4</sub>HCO<sub>3</sub>-derived CoCu<sub>0.2</sub> sample exhibited better catalytic efficiency in toluene oxidation, while the T<sub>90</sub> were 22 and 28°C lower than those samples prepared by NaOH and H<sub>2</sub>C<sub>2</sub>O<sub>4</sub> routes, respectively. Based on various characterizations, it could be deduced that the excellent performance was related to the small crystal size (6.7 nm), large specific surface area (77.0 m<sup>2</sup>/g), hollow hierarchical nanostructure with abundant high valence Co ions and adsorbed oxygen species. In situ DRIFTS further revealed that the possible reaction pathway for the toluene oxidation over CoCu<sub>0.2</sub> catalyst followed the route of absorbed toluene → benzyl alcohol → benzaldehyde → benzoic acid → carbonate → CO<sub>2</sub> and H<sub>2</sub>O. In addition, CoCu<sub>0.2</sub> sample could keep stable with long-time operation and occur little inactivation under humid condition (5 vol.% water), which revealed that the NH<sub>4</sub>HCO<sub>3</sub>-derived CoCu<sub>0.2</sub> nanocatalyst possessed great potential in industrial applications for VOCs abatement.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140947975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-27DOI: 10.1016/j.jes.2024.04.028
Chao Wang , Shuhan Gong , Yun Cao , Mengmeng Liu , Wenying Zhang , Xiaotong Zhang , Lin Fan , Li Li , Hang Du , Mats Tysklind , Xu Yang , Xianliang Wang
To explore the multicenter characteristics of endocrine-like phthalate esters (PAEs) in household dust and propose effective control strategies for global indoor public health. An on-site observational investigation was conducted in nine Chinese cities from 2018 to 2019. A total of 246 household dust samples were collected and analyzed for ten PAE congeners using Gas Chromatography-Mass Spectrometry (GC-MS). Questionnaires were used to gather information on building conditions, indoor behaviors, and ventilation habits. In residential dust from the nine cities, the total concentrations of the ten PAE congeners (∑PAEs) ranged from 0.921 to 29097.297 µg/g. Dicyclohexyl phthalate (DCHP) and di (2-ethylhexyl) phthalate (DEHP) were the dominant congeners in ∑PAEs. Childhood exposure to PAEs through dust ingestion was four orders of magnitude higher than through inhalation, with a carcinogenic risk of 5.47 × 10−6 for DEHP exposure in household dust. Higher ∑PAEs concentrations were associated with higher temperature, double glazing, wall paint usage, television and computer use, and indoor plant growth. This multicenter on-site investigation confirmed PAE pollution characteristics and uncovered the inacceptable risk of daily DEHP exposure in household dust under real living conditions. Effective mitigation measures based on household-related information, residential characteristics, decoration materials, and lifestyle should be taken to build a healthy household environment.
{"title":"Characterization and sources of childhood PAEs exposure from residential airborne dust in China cities","authors":"Chao Wang , Shuhan Gong , Yun Cao , Mengmeng Liu , Wenying Zhang , Xiaotong Zhang , Lin Fan , Li Li , Hang Du , Mats Tysklind , Xu Yang , Xianliang Wang","doi":"10.1016/j.jes.2024.04.028","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.028","url":null,"abstract":"<div><p>To explore the multicenter characteristics of endocrine-like phthalate esters (PAEs) in household dust and propose effective control strategies for global indoor public health. An on-site observational investigation was conducted in nine Chinese cities from 2018 to 2019. A total of 246 household dust samples were collected and analyzed for ten PAE congeners using Gas Chromatography-Mass Spectrometry (GC-MS). Questionnaires were used to gather information on building conditions, indoor behaviors, and ventilation habits. In residential dust from the nine cities, the total concentrations of the ten PAE congeners (∑PAEs) ranged from 0.921 to 29097.297 µg/g. Dicyclohexyl phthalate (DCHP) and di (2-ethylhexyl) phthalate (DEHP) were the dominant congeners in ∑PAEs. Childhood exposure to PAEs through dust ingestion was four orders of magnitude higher than through inhalation, with a carcinogenic risk of 5.47 × 10<sup>−6</sup> for DEHP exposure in household dust. Higher ∑PAEs concentrations were associated with higher temperature, double glazing, wall paint usage, television and computer use, and indoor plant growth. This multicenter on-site investigation confirmed PAE pollution characteristics and uncovered the inacceptable risk of daily DEHP exposure in household dust under real living conditions. Effective mitigation measures based on household-related information, residential characteristics, decoration materials, and lifestyle should be taken to build a healthy household environment.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140917966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-27DOI: 10.1016/j.jes.2024.04.035
Shuya Hu , Linghan Zeng , Gang Zhao , Shiyi Chen , Chunsheng Zhao , Weilun Zhao , Min Hu
The ambient air quality has improved significantly under strict emission controls in Beijing, China over the last decade. Black carbon (BC), as a short-lived climate forcer in ambient aerosols, profoundly impacts the air quality and climate. Previous studies have demonstrated a decline in the mass concentration of BC. In this study, we characterized the chemical compositions and size distributions of BC-containing particles during the cold season of 2022 in Beijing using state-of-the-art instruments capable of exclusively measuring BC-containing particles. The optical properties of BC-containing particles were further calculated based on the Mie theory. Moreover, we compared the properties of BC-containing particles in 2022 with the results of previous studies. The results showed that the diameters of BC cores became larger while the coating thickness of BC-containing particles became thinner in 2022. For the coating materials, the mass fraction of nitrate increased obviously, and even replaced organic matter as the dominant component during the peak of the pollution period. Variations in chemical compositions and size distributions resulted in lower mass absorption cross-sections (MAC) of BC-containing particles from 10.5 ± 1.1 m2/g in 2016 to 7.3 ± 0.8 m2/g in 2022, reduced by 30.5%. Our results demonstrate the synergistic benefits of air pollution control in improving air quality and mitigating climate change. Therefore, the MAC of BC adopted in climate models should vary with the changing air pollution levels. This study emphasizes that it is imperative to conduct long-term observations of BC-containing particles to better estimate BC's climate effects.
过去十年间,在严格的排放控制下,中国北京的环境空气质量得到了显著改善。黑碳(BC)作为环境气溶胶中的一种短寿命气候诱变剂,对空气质量和气候有着深远的影响。以往的研究表明,黑碳的质量浓度在下降。在本研究中,我们使用能够专门测量含 BC 颗粒物的先进仪器,对 2022 年北京寒冷季节含 BC 颗粒物的化学成分和粒径分布进行了表征。根据米氏理论进一步计算了含 BC 粒子的光学特性。此外,我们还将 2022 年含 BC 粒子的特性与之前的研究结果进行了比较。结果表明,2022 年含 BC 粒子的内核直径变大,而涂层厚度变薄。在涂层材料中,硝酸盐的质量分数明显增加,在污染高峰期甚至取代有机物成为主要成分。化学成分和粒度分布的变化导致含 BC 颗粒的质量吸收截面(MAC)降低,从 2016 年的 10.5 ± 1.1 m2/g 降至 2022 年的 7.3 ± 0.8 m2/g,降幅达 30.5%。我们的研究结果表明了空气污染控制在改善空气质量和减缓气候变化方面的协同效益。因此,气候模型中采用的 BC MAC 应随空气污染水平的变化而变化。这项研究强调,必须对含 BC 颗粒物进行长期观测,以更好地估计 BC 的气候效应。
{"title":"Significant changes in the physicochemical properties of BC-containing particles during the cold season in Beijing","authors":"Shuya Hu , Linghan Zeng , Gang Zhao , Shiyi Chen , Chunsheng Zhao , Weilun Zhao , Min Hu","doi":"10.1016/j.jes.2024.04.035","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.035","url":null,"abstract":"<div><p>The ambient air quality has improved significantly under strict emission controls in Beijing, China over the last decade. Black carbon (BC), as a short-lived climate forcer in ambient aerosols, profoundly impacts the air quality and climate. Previous studies have demonstrated a decline in the mass concentration of BC. In this study, we characterized the chemical compositions and size distributions of BC-containing particles during the cold season of 2022 in Beijing using state-of-the-art instruments capable of exclusively measuring BC-containing particles. The optical properties of BC-containing particles were further calculated based on the Mie theory. Moreover, we compared the properties of BC-containing particles in 2022 with the results of previous studies. The results showed that the diameters of BC cores became larger while the coating thickness of BC-containing particles became thinner in 2022. For the coating materials, the mass fraction of nitrate increased obviously, and even replaced organic matter as the dominant component during the peak of the pollution period. Variations in chemical compositions and size distributions resulted in lower mass absorption cross-sections (MAC) of BC-containing particles from 10.5 ± 1.1 m<sup>2</sup>/g in 2016 to 7.3 ± 0.8 m<sup>2</sup>/g in 2022, reduced by 30.5%. Our results demonstrate the synergistic benefits of air pollution control in improving air quality and mitigating climate change. Therefore, the MAC of BC adopted in climate models should vary with the changing air pollution levels. This study emphasizes that it is imperative to conduct long-term observations of BC-containing particles to better estimate BC's climate effects.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140906190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-27DOI: 10.1016/j.jes.2024.04.033
Ya-Ting Liu , Bo-Fang Yan , Xuan Cai , Hong-Xiang Zheng , Rong-Liang Qiu , Ye-Tao Tang
The accumulation of Cd by rice poses significant health risks. Foliar fertilization with Zn can reduce grain Cd contents in rice grown in Cd-contaminated soils. However, atmospheric deposition on leaves is another vector of Cd contamination, and it remains unclear how Zn application affects the allocation of such Cd. We conducted an experiment where the flag leaves of rice plants were treated with solutions with various Zn concentrations and a constant Cd concentration. The 111Cd stable isotope was used to trace the flux of foliar-applied Cd. Higher levels of foliar-applied Zn enhanced Cd efflux and grain allocation. This is attributed to limited sequestration of foliar-applied Cd in the leaf cell symplasm and increased Cd desorption from leaf cell walls when a high Zn2+ concentration occurs in the apoplast. Nonionic Zn oxide nanoparticles mitigated these effects. Additionally, the expressions of OsLCT1 and OsZIP7 in flag leaves and OsHMA2 and OsZIP7 in the uppermost nodes were upregulated under high-Zn2+ treatment, which may facilitate Cd phloem loading and grain allocation. Caution is advised in using foliar Zn in areas with high atmospheric Cd due to potential grain-contamination risks.
{"title":"Foliar-applied zinc promotes cadmium allocation from leaf surfaces to grains in rice","authors":"Ya-Ting Liu , Bo-Fang Yan , Xuan Cai , Hong-Xiang Zheng , Rong-Liang Qiu , Ye-Tao Tang","doi":"10.1016/j.jes.2024.04.033","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.033","url":null,"abstract":"<div><p>The accumulation of Cd by rice poses significant health risks. Foliar fertilization with Zn can reduce grain Cd contents in rice grown in Cd-contaminated soils. However, atmospheric deposition on leaves is another vector of Cd contamination, and it remains unclear how Zn application affects the allocation of such Cd. We conducted an experiment where the flag leaves of rice plants were treated with solutions with various Zn concentrations and a constant Cd concentration. The <sup>111</sup>Cd stable isotope was used to trace the flux of foliar-applied Cd. Higher levels of foliar-applied Zn enhanced Cd efflux and grain allocation. This is attributed to limited sequestration of foliar-applied Cd in the leaf cell symplasm and increased Cd desorption from leaf cell walls when a high Zn<sup>2+</sup> concentration occurs in the apoplast. Nonionic Zn oxide nanoparticles mitigated these effects. Additionally, the expressions of <em>OsLCT1</em> and <em>OsZIP7</em> in flag leaves and <em>OsHMA2</em> and <em>OsZIP7</em> in the uppermost nodes were upregulated under high-Zn<sup>2+</sup> treatment, which may facilitate Cd phloem loading and grain allocation. Caution is advised in using foliar Zn in areas with high atmospheric Cd due to potential grain-contamination risks.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140843519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-27DOI: 10.1016/j.jes.2024.04.032
Baoshuang Liu , Tao Yang , Sicong Kang , Fuquan Wang , Haixu Zhang , Man Xu , Wei Wang , Jinrui Bai , Shaojie Song , Qili Dai , Yinchang Feng , Philip K. Hopke
Substantial effects of photochemical reaction losses of volatile organic compounds (VOCs) on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved profiles. Hourly speciated VOC data measured in Shijiazhuang, China from May to September 2021 were used to conduct study. The mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv, respectively. Alkanes and aromatics concentrations in the daytime (12.9 and 3.08 ppbv) were lower than nighttime (15.5 and 3.63 ppbv), whereas that of alkenes showed the opposite tendency. The concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbons were uniformly small. The reactivities of the dominant species in factor profiles for gasoline emissions, natural gas and diesel vehicles, and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical losses. Photochemical losses produced a substantial impact on the profiles of solvent use, petrochemical industry emissions, combustion sources, and biogenic emissions where the dominant species in these factor profiles had high reactivities. Although the profile of biogenic emissions was substantially affected by photochemical loss of isoprene, the low emissions at nighttime also had an important impact on its profile. Chemical losses of highly active VOC species substantially reduced their concentrations in apportioned factor profiles. This study results were consistent with the analytical results obtained through initial concentration estimation, suggesting that the initial concentration estimation could be the most effective currently available method for the source analyses of active VOCs although with uncertainty.
{"title":"Changes in factor profiles deriving from photochemical losses of volatile organic compounds: Insight from daytime and nighttime positive matrix factorization analyses","authors":"Baoshuang Liu , Tao Yang , Sicong Kang , Fuquan Wang , Haixu Zhang , Man Xu , Wei Wang , Jinrui Bai , Shaojie Song , Qili Dai , Yinchang Feng , Philip K. Hopke","doi":"10.1016/j.jes.2024.04.032","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.032","url":null,"abstract":"<div><p>Substantial effects of photochemical reaction losses of volatile organic compounds (VOCs) on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved profiles. Hourly speciated VOC data measured in Shijiazhuang, China from May to September 2021 were used to conduct study. The mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv, respectively. Alkanes and aromatics concentrations in the daytime (12.9 and 3.08 ppbv) were lower than nighttime (15.5 and 3.63 ppbv), whereas that of alkenes showed the opposite tendency. The concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbons were uniformly small. The reactivities of the dominant species in factor profiles for gasoline emissions, natural gas and diesel vehicles, and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical losses. Photochemical losses produced a substantial impact on the profiles of solvent use, petrochemical industry emissions, combustion sources, and biogenic emissions where the dominant species in these factor profiles had high reactivities. Although the profile of biogenic emissions was substantially affected by photochemical loss of isoprene, the low emissions at nighttime also had an important impact on its profile. Chemical losses of highly active VOC species substantially reduced their concentrations in apportioned factor profiles. This study results were consistent with the analytical results obtained through initial concentration estimation, suggesting that the initial concentration estimation could be the most effective currently available method for the source analyses of active VOCs although with uncertainty.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140905671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-26DOI: 10.1016/j.jes.2024.04.024
Hongmei Ren , Ang Li , Zhaokun Hu , Hairong Zhang , Jiangman Xu , Xinyan Yang , Jinji Ma , Shuai Wang
Studying the spatiotemporal distribution and transboundary transport of aerosols, NO2, SO2, and HCHO in typical regions is crucial for understanding regional pollution causes. In a 2-year study using multi-axis differential optical absorption spectroscopy in Qingdao, Shanghai, Xi'an, and Kunming, we investigated pollutant distribution and transport across Eastern China-Ocean, Tibetan Plateau-Central and Eastern China, and China-Southeast Asia interfaces. First, pollutant distribution was analyzed. Kunming, frequently clouded and misty, exhibited consistently high aerosol optical depth throughout the year. In Qingdao and Shanghai, NO2 and SO2, as well as SO2 in Xi'an, increased in winter. Elevated HCHO in summer in Shanghai and Xi'an, especially Xi'an, suggests potential ozone pollution issues. Subsequently, pollutant transportation across interfaces was studied. At the Eastern China-Ocean interface, the gas transport flux was the largest among other interfaces, with the outflux exceeding the influx, especially in winter and spring. The input of pollutants from the Tibetan Plateau to central-eastern China was larger than the output in winter and spring, with SO2 having the highest transport flux in winter. The pollution input from Southeast Asia to China significantly exceeded the output, with spring and winter inputs being 3.22 and 3.03 times the output, respectively. Lastly, the transportation characteristics of a pollution event at Kunming were studied. During this period, pollutants were transported from west to east, with the maximum SO2 transport flux at an altitude of 2.87 km equaling 27.74 µg/(m2·s). It is speculated that this pollution was caused by the transport from Southeast Asian countries to Kunming.
{"title":"MAX-DOAS observations of pollutant distribution and transboundary transport in typical regions of China","authors":"Hongmei Ren , Ang Li , Zhaokun Hu , Hairong Zhang , Jiangman Xu , Xinyan Yang , Jinji Ma , Shuai Wang","doi":"10.1016/j.jes.2024.04.024","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.024","url":null,"abstract":"<div><p>Studying the spatiotemporal distribution and transboundary transport of aerosols, NO<sub>2</sub>, SO<sub>2</sub>, and HCHO in typical regions is crucial for understanding regional pollution causes. In a 2-year study using multi-axis differential optical absorption spectroscopy in Qingdao, Shanghai, Xi'an, and Kunming, we investigated pollutant distribution and transport across Eastern China-Ocean, Tibetan Plateau-Central and Eastern China, and China-Southeast Asia interfaces. First, pollutant distribution was analyzed. Kunming, frequently clouded and misty, exhibited consistently high aerosol optical depth throughout the year. In Qingdao and Shanghai, NO<sub>2</sub> and SO<sub>2</sub>, as well as SO<sub>2</sub> in Xi'an, increased in winter. Elevated HCHO in summer in Shanghai and Xi'an, especially Xi'an, suggests potential ozone pollution issues. Subsequently, pollutant transportation across interfaces was studied. At the Eastern China-Ocean interface, the gas transport flux was the largest among other interfaces, with the outflux exceeding the influx, especially in winter and spring. The input of pollutants from the Tibetan Plateau to central-eastern China was larger than the output in winter and spring, with SO<sub>2</sub> having the highest transport flux in winter. The pollution input from Southeast Asia to China significantly exceeded the output, with spring and winter inputs being 3.22 and 3.03 times the output, respectively. Lastly, the transportation characteristics of a pollution event at Kunming were studied. During this period, pollutants were transported from west to east, with the maximum SO<sub>2</sub> transport flux at an altitude of 2.87 km equaling 27.74 µg/(m<sup>2</sup>·s). It is speculated that this pollution was caused by the transport from Southeast Asian countries to Kunming.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140906189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-26DOI: 10.1016/j.jes.2024.04.012
Shuaitao Li , Haodi Liu , Xun Hu , Yanfen Fang , Xiaofeng Cao , Qifeng Chen
Volatile Organic Compounds (VOCs) are highly harmful to human beings and other organisms, and thus the elimination of VOCs is extremely urgent. Here, La-Si co-doped TiO2 microsphere photocatalysts, which were prepared by a hydrothermal method, exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO2. The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers, as verified by the electrochemical results in combination with density functional theory calculations. In addition, the Si dopant changed the microstructure and surface acidity, while the addition of La promoted the separation efficiency of charge carriers. More interestingly, it was found that singlet oxygen was the key species in the activation of molecular dioxygen, and it played a pivotal role in the photocatalytic decomposition of formaldehyde. This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.
{"title":"Selective activation of dioxygen to singlet oxygen over La-Si co-doped TiO2 microspheres for photocatalytic degradation of formaldehyde","authors":"Shuaitao Li , Haodi Liu , Xun Hu , Yanfen Fang , Xiaofeng Cao , Qifeng Chen","doi":"10.1016/j.jes.2024.04.012","DOIUrl":"https://doi.org/10.1016/j.jes.2024.04.012","url":null,"abstract":"<div><p>Volatile Organic Compounds (VOCs) are highly harmful to human beings and other organisms, and thus the elimination of VOCs is extremely urgent. Here, La-Si co-doped TiO<sub>2</sub> microsphere photocatalysts, which were prepared by a hydrothermal method, exhibited high photocatalytic activity in the decomposition of formaldehyde compared with TiO<sub>2</sub>. The improved activity can be attributed to the promoted separation efficiency and density of the charge carriers, as verified by the electrochemical results in combination with density functional theory calculations. In addition, the Si dopant changed the microstructure and surface acidity, while the addition of La promoted the separation efficiency of charge carriers. More interestingly, it was found that singlet oxygen was the key species in the activation of molecular dioxygen, and it played a pivotal role in the photocatalytic decomposition of formaldehyde. This work provides a novel strategy for the selective activation of dioxygen for use in the decomposition of formaldehyde.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140894564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-25DOI: 10.1016/j.jes.2024.04.023
Shuaishuai Ma , Dongsheng Cheng , Yingying Tang , Younuo Fan , Qiong Li , Chengxiang He , Zhiqing Zhao , Tianyou Xu
Inhalation of atmospheric PM2.5 can induce the generation of excessive reactive oxygen species (ROS) in human alveoli, triggering local and systemic inflammation, which can directly or indirectly result in respiratory and cardiovascular diseases. In this study, we assessed the oxidative potential (OP) of fresh and O3-aged PM2.5 particles from various urban and rural emission sources using the dithiothreitol (DTT) method. Our results revealed variations in the OP of fresh PM2.5 among different emission sources, with biomass burning sources exhibiting the highest OP, followed by industrial areas, vehicular emissions, cooking emissions, and suburban areas, respectively. Water-soluble organics and transition metals might potentially exert significant influence on particle OP. O3 aging notably decreased the OP of PM2.5 particles, possibly due to the oxidation of highly DTT-active components into low redox-active small molecules. Moreover, the evolution of OP in different PM2.5 components, including methanol-soluble and insoluble fractions, exhibited distinct responses to O3 aging for source-oriented PM2.5. Additionally, differences in chemical composition between fresh and aged PM2.5 were further elucidated through measurements of component-dependent hygroscopic behaviors and phase transitions. This study systematically delineates variances in the toxic potential of fresh and O3-aged PM2.5 from various anthropogenic sources. The findings highlight the intrinsic compositional dependence of particle OP and provide essential insights for assessing the health effects of source-oriented PM2.5, as well as for formulating human health protection policies.
吸入大气中的 PM2.5 可诱导人体肺泡产生过量的活性氧(ROS),引发局部和全身炎症,从而直接或间接导致呼吸系统和心血管疾病。在这项研究中,我们采用二硫苏糖醇(DTT)法评估了来自不同城市和农村排放源的新鲜和O3老化PM2.5颗粒的氧化潜能(OP)。结果表明,不同排放源的新鲜PM2.5氧化潜势存在差异,其中生物质燃烧源的氧化潜势最高,其次分别是工业区、车辆排放、烹饪排放和郊区。水溶性有机物和过渡金属可能会对颗粒物的 OP 产生重要影响。O3老化显著降低了PM2.5颗粒的OP,这可能是由于高DTT活性成分被氧化成低氧化还原活性的小分子。此外,对于以污染源为导向的 PM2.5,PM2.5 不同组分(包括甲醇可溶组分和不溶组分)的 OP 演变对臭氧老化的反应各不相同。此外,通过测量与组分相关的吸湿行为和相变,进一步阐明了新鲜和老化 PM2.5 化学成分的差异。这项研究系统地描述了各种人为来源的新鲜和 O3 老化 PM2.5 的毒性潜力差异。研究结果凸显了颗粒 OP 的内在成分依赖性,并为评估以来源为导向的 PM2.5 对健康的影响以及制定人类健康保护政策提供了重要见解。
{"title":"Investigation of oxidative potential of fresh and O3-aging PM2.5 from various emission sources across urban and rural regions","authors":"Shuaishuai Ma , Dongsheng Cheng , Yingying Tang , Younuo Fan , Qiong Li , Chengxiang He , Zhiqing Zhao , Tianyou Xu","doi":"10.1016/j.jes.2024.04.023","DOIUrl":"10.1016/j.jes.2024.04.023","url":null,"abstract":"<div><p>Inhalation of atmospheric PM<sub>2.5</sub> can induce the generation of excessive reactive oxygen species (ROS) in human alveoli, triggering local and systemic inflammation, which can directly or indirectly result in respiratory and cardiovascular diseases. In this study, we assessed the oxidative potential (OP) of fresh and O<sub>3</sub>-aged PM<sub>2.5</sub> particles from various urban and rural emission sources using the dithiothreitol (DTT) method. Our results revealed variations in the OP of fresh PM<sub>2.5</sub> among different emission sources, with biomass burning sources exhibiting the highest OP, followed by industrial areas, vehicular emissions, cooking emissions, and suburban areas, respectively. Water-soluble organics and transition metals might potentially exert significant influence on particle OP. O<sub>3</sub> aging notably decreased the OP of PM<sub>2.5</sub> particles, possibly due to the oxidation of highly DTT-active components into low redox-active small molecules. Moreover, the evolution of OP in different PM<sub>2.5</sub> components, including methanol-soluble and insoluble fractions, exhibited distinct responses to O<sub>3</sub> aging for source-oriented PM<sub>2.5</sub>. Additionally, differences in chemical composition between fresh and aged PM<sub>2.5</sub> were further elucidated through measurements of component-dependent hygroscopic behaviors and phase transitions. This study systematically delineates variances in the toxic potential of fresh and O<sub>3</sub>-aged PM<sub>2.5</sub> from various anthropogenic sources. The findings highlight the intrinsic compositional dependence of particle OP and provide essential insights for assessing the health effects of source-oriented PM<sub>2.5</sub>, as well as for formulating human health protection policies.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140778054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}
Pub Date : 2024-04-25DOI: 10.1016/j.jes.2024.04.021
Rui Chen , Tangbing Cui
Benzo[a]pyrene (B[a]P) is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain. It is therefore essential to treat and remediate the B[a]P-contaminated environment. Microbial remediation of B[a]P-contaminated environments is considered to be one of the most effective strategies, and the addition of biostimulants is a feasible method to further improve the effectiveness of microbial remediation. In this study, we used Bacillus subtilis MSC4 to screen for the stimulation of sodium gluconate, which promoted B[a]P degradation. Based on biochemical and transcriptomic analyses, Sodium gluconate was found to significantly increase the biomass of MSC4 and the expression of most genes involved in B[a]P degradation. Activities of central carbon metabolism, fatty acid β-oxidation and oxidative phosphorylation were all promoted. The significant increase in acid-induced oxalate decarboxylase expression indicates a decrease in intracellular pH, which promoted the synthesis of acetoin and lactate. Genes involved in the nitrogen cycle, especially nitrification and denitrification, were significantly up-regulated, contributing to B[a]P degradation. Genes involved in the synthesis of enzyme cofactors, including thiamine, molybdenum cofactors, NAD and heme, were up-regulated, which contributes to increasing enzyme activity in metabolic pathways. Up-regulation of genes in flagella assembly, chemotaxis, and lipopeptide synthesis is beneficial for the dissolution and uptake of B[a]P. Genes related to the sugar transport system were upregulated, which facilitates the transport and absorption of monosaccharides and oligosaccharides by MSC4. This study provides a theoretical basis for the further application of sodium gluconate in the treatment of PAH-contaminated sites.
{"title":"Transcriptomic and biochemical analysis of the mechanism of sodium gluconate promoting the degradation of benzo [a] pyrene by Bacillus subtilis MSC4","authors":"Rui Chen , Tangbing Cui","doi":"10.1016/j.jes.2024.04.021","DOIUrl":"10.1016/j.jes.2024.04.021","url":null,"abstract":"<div><p>Benzo[a]pyrene (B[a]P) is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain. It is therefore essential to treat and remediate the B[a]P-contaminated environment. Microbial remediation of B[a]P-contaminated environments is considered to be one of the most effective strategies, and the addition of biostimulants is a feasible method to further improve the effectiveness of microbial remediation. In this study, we used <em>Bacillus subtilis</em> MSC4 to screen for the stimulation of sodium gluconate, which promoted B[a]P degradation. Based on biochemical and transcriptomic analyses, Sodium gluconate was found to significantly increase the biomass of MSC4 and the expression of most genes involved in B[a]P degradation. Activities of central carbon metabolism, fatty acid β-oxidation and oxidative phosphorylation were all promoted. The significant increase in acid-induced oxalate decarboxylase expression indicates a decrease in intracellular pH, which promoted the synthesis of acetoin and lactate. Genes involved in the nitrogen cycle, especially nitrification and denitrification, were significantly up-regulated, contributing to B[a]P degradation. Genes involved in the synthesis of enzyme cofactors, including thiamine, molybdenum cofactors, NAD and heme, were up-regulated, which contributes to increasing enzyme activity in metabolic pathways. Up-regulation of genes in flagella assembly, chemotaxis, and lipopeptide synthesis is beneficial for the dissolution and uptake of B[a]P. Genes related to the sugar transport system were upregulated, which facilitates the transport and absorption of monosaccharides and oligosaccharides by MSC4. This study provides a theoretical basis for the further application of sodium gluconate in the treatment of PAH-contaminated sites.</p></div>","PeriodicalId":15788,"journal":{"name":"Journal of Environmental Sciences-china","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140795336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}