Environmental Science: Processes & Impacts最新文献

{"title":"Combined temperature and salinity effects on the passive sampling of PAHs with an assessment of impacts to petroleum toxicity†","authors":"Ibukun Ola, Carsten Drebenstedt, Robert M. Burgess, Lane Tidwell, Kim Anderson, Nils Hoth and Christoph Külls","doi":"10.1039/D4EM00133H","DOIUrl":"10.1039/D4EM00133H","url":null,"abstract":"<p >In equilibrium-based passive sampling applications, the accuracy of estimating freely dissolved concentration (<em>C</em><small><sub>free</sub></small>) of hydrophobic organic compounds (HOCs) relies on the passive sampler–water partition coefficient (<em>K</em><small><sub>PS–W</sub></small>) values applied. The vast majority of <em>K</em><small><sub>PS–W</sub></small> are generated under standard conditions: 20 °C in deionized or freshwater. Few empirically derived values are available for non-standard conditions. In this study, polyethylene (PE)–water partitioning coefficients (<em>K</em><small><sub>PE–W</sub></small>) were experimentally determined for 15 polycyclic aromatic hydrocarbons (PAHs, comprising 9 parent and 6 alkylated compounds) under three different temperature (10, 20, 30 °C) and salinity (0, 18 and 36‰) regimes, the <em>K</em><small><sub>PE–W</sub></small> values were found to correlate strongly with a variety of molecular parameters (<em>e.g.</em>, octanol–water partition coefficients (<em>K</em><small><sub>OW</sub></small>), molecular weight (MW) and molecular volume (<em>M</em><small><sub>VOL</sub></small>)). The effects of temperature and salinity on the magnitude of <em>K</em><small><sub>PE–W</sub></small> were found to be substantial. For temperature, the values range between −0.005 and −0.023 log units per °C; these values indicate that every 10 °C rise in temperature would potentially decrease the <em>K</em><small><sub>PE–W</sub></small> by a factor of between 0.4 to 1.6. For salinity, the values range from 0.0028 to 0.0057 log units per unit ‰, indicating that an 18‰ increase in salinity would likely increase the <em>K</em><small><sub>PE–W</sub></small> by a factor of between 0.28 and 0.82. Moreover, temperature and salinity were shown to be independent of each other and non-interacting. Temperature effects were chemical-specific and moderately dependent on hydrophobicity (expressed as the <em>K</em><small><sub>OW</sub></small>), whereas salinity effects were independent of hydrophobicity. We also assessed the combined impact of temperature and salinity, which showed increasing effects with the hydrophobicity of the PAHs studied. Based on the results, <em>K</em><small><sub>PE–W</sub></small> values adjusted for site-specific temperature and salinity can be calculated. The impact of applying such site-specific values was demonstrated using a PE-based field monitoring dataset for PAHs from coastal waters of Grand Isle (LA, USA) collected during the 2010 Deepwater Horizon oil spill. When <em>K</em><small><sub>PE–W</sub></small> values were adjusted to 10 °C and 30 °C, the final freely dissolved concentrations (<em>C</em><small><sub>free</sub></small>) decreased or increased depending on the adjustment. Use of the results of this investigation allow for adjusting existing PE-based datasets to site-specific conditions resulting in more accurate <em>C</em><small><sub>free</sub></small> values for estimating exposure and a","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 2076-2089"},"PeriodicalIF":4.3,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00133h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Indoor air concentrations of PM_2.5 quartz fiber filter-collected ionic PFAS and emissions to outdoor air: findings from the IPA campaign.","authors":"Naomi Y Chang, Clara M A Eichler, Daniel E Amparo, Jiaqi Zhou, Karsten Baumann, Elaine A Cohen Hubal, Jason D Surratt, Glenn C Morrison, Barbara J Turpin","doi":"10.1039/d4em00359d","DOIUrl":"10.1039/d4em00359d","url":null,"abstract":"<p><p>Per- and polyfluoroalkyl substances (PFAS) are prevalent in consumer products used indoors. However, few measurements of ionic PFAS exist for indoor air. We analyzed samples collected on PM_2.5 quartz fiber filters (QFFs) in 11 North Carolina homes 1-3 times in living rooms (two QFFs in series), and immediately outside each home (single QFF), for 26 ionic PFAS as part of the 9 months Indoor PFAS Assessment (IPA) Campaign. All targeted PFAS, except for PFDS and 8:2 monoPAP, were detected indoors. PFBA, PFHpA, PFHxA, PFOA, PFOS, and 6:2 diPAP were detected in >50% of indoor samples. PFHxA, PFOA, and PFOS had the highest detection frequency (DF = 80%; medians = 0.5-0.7 pg m^-3), while median PFBA concentrations (3.6 pg m^-3; DF = 67%) were highest indoors. Residential indoor air concentrations (sum of measured PFAS) were, on average, 3.4 times higher than residential outdoor air concentrations, and an order of magnitude higher than regional background concentrations. Indoor-to-outdoor emission rate estimates suggest that emissions from single unit homes could be a meaningful contributor to PFBA, PFOA, and PFOS emissions in populated areas far from major point sources. Backup QFFs were observed to adsorb some targeted PFAS from the gas-phase, making reported values upper-bounds for particle-phase and lower-bounds for total air (gas plus particle) concentrations. We found that higher concentrations of carbonaceous aerosol were associated with a shift in partitioning of short chain PFCAs and long chain PFSAs toward the particle phase.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.3,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Finding non-fluorinated alternatives to fluorinated gases used as refrigerants†","authors":"Juliane Glüge, Katharina Breuer, Armin Hafner, Christian Vering, Dirk Müller, Ian T. Cousins, Rainer Lohmann, Gretta Goldenman and Martin Scheringer","doi":"10.1039/D4EM00444B","DOIUrl":"10.1039/D4EM00444B","url":null,"abstract":"<p >Hydrofluorocarbons (HFCs) and so-called hydrofluoroolefins (HFOs) are used as refrigerants in air conditioning, refrigeration, chillers, heat pumps and devices for dehumidification and drying. However, many HFCs, including R-134a and R-125, have a high global warming potential and some of the HFCs and HFOs degrade atmospherically and form trifluoroacetic acid (TFA) as a persistent degradation product. Rising levels of TFA around the globe reveal an urgent need to replace fluorinated refrigerants with non-fluorinated working fluids to avoid direct emissions due to leakage, incorrect loading or removal. It is important, however, also to select refrigerants with high efficiencies to avoid increasing indirect CO<small>₂</small> emissions due to higher energy consumption during the use phase. The present study investigates the available non-fluorinated alternatives to fluorinated refrigerants and shows that a transition to non-fluorinated refrigerants, in general, is possible and has happened in many sectors already. Technically, there are only slight barriers to overcome in order to replace fluorinated refrigerants in almost all newly developed systems conforming to existing standards. Additionally, we show that alternatives are available even for some use cases for which derogations have been proposed in the EU PFAS restriction proposal and suggest making these derogations more specific to support a speedy transition to non-fluorinated refrigerants in all sectors.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 1955-1974"},"PeriodicalIF":4.3,"publicationDate":"2024-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11448211/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142363524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Associations of indoor airborne microbiome with lung function: evidence from a randomized, double-blind, crossover study of microbial intervention†","authors":"Yetong Zhao, Shan Liu, Wanzhou Wang, Luyi Li, Wenlou Zhang, Xuezhao Ji, Di Yang, Xinbiao Guo and Furong Deng","doi":"10.1039/D4EM00392F","DOIUrl":"10.1039/D4EM00392F","url":null,"abstract":"<p >Microorganisms constitute an essential component of the indoor ecosystem and may pose potential health risks after inhalation. However, evidence regarding the impact of indoor airborne microbiome on general respiratory health is scarce. Additionally, while air purification has been shown to be an effective strategy for controlling culturable bioaerosols, its impact on indoor airborne microbiome remains unclear. To determine the impact of indoor airborne microbial exposure on lung function, and whether and how air purification can modify indoor airborne microbiome, we conducted a randomized, double-blind, crossover study employing air purification intervention among 68 healthy young adults in Beijing, China. Indoor airborne bacteria and fungi were characterized using amplicon sequencing technology and quantified by qPCR. Our results indicated positive associations between indoor airborne microbial α-diversity and lung function indices; however, adverse effects from total microbial load were observed. Males were more susceptible to microbial exposure than females. Beneficial effects from richness in Actinobacteria, Bacteroidia, Oxyphotobacteria, Bacilli, Clostridia, Alphaproteobacteria, Gammaproteobacteria, Dothideomycetes, and Sordariomycetes, and detrimental effects from five Proteobacteria genera, including <em>Dechloromonas</em>, <em>Hydrogenophaga</em>, <em>Klebsiella</em>, <em>Pseudomonas</em>, and <em>Tolumonas</em>, were also identified. Air purification contributed to decreased fungal diversity and total fungal load, but not the overall microbial community structure. Our study demonstrates the significant role of indoor airborne microbiome in regulating human respiratory health and provides inspiration for improving health through manipulation of indoor microbiome. Meanwhile, our study also underscores the importance of balancing the potential benefits from decreased microbial load and the underlying risks from reduced microbial diversity while applying environmental microbial interventions.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 2020-2035"},"PeriodicalIF":4.3,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142360781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Physicochemical properties and their impact on ice nucleation efficiency of respiratory viral RNA and proteins†","authors":"Mattie Hibbs, Devendra Pal, Gorjana Barudzija and Parisa A. Ariya","doi":"10.1039/D4EM00411F","DOIUrl":"10.1039/D4EM00411F","url":null,"abstract":"<p >Ice nucleation processes in the earth's atmosphere are critical for cloud formation, radiation, precipitation, and climate change. We investigated the physicochemical properties and ice nucleation potential of selected viral aerosols, including their RNA and proteins, using advanced techniques such as scanning-transmission electron microscopy (S/TEM), small angle X-ray scattering (SAXS), particle analyzers, and a peltier chamber. The experiments revealed that RNA particles obtained from MS2 bacteriophage had a mean freezing point of −13.9 ± 0.3 °C, comparable to the average ice nucleation temperature of global dust particles, which is approximatively −15 °C. RNA from MS2, Influenza, SARS-CoV-1 and SARS-CoV-2 demonstrated average ice nucleation temperatures of −13.9 ± 0.3 °C, −13.7 ± 0.3 °C, −13.7 ± 0.3 °C, and −15.9 ± 0.4 °C, respectively. SAXS analysis indicated a high local crystallinity value of 0.5 of MS2 RNA particles, hinting that high crystalline nature may contribute to their effectiveness as ice nuclei. Dilution experiments show that viral RNA consistently catalyzes ice nucleation. The addition of dust-containing particles, such as Fe<small>₂</small>O<small>₃</small>, CuO, and TiO<small>₂</small>, to MS2 bacteriophage droplets enhanced ice nucleation, as did UV radiation. We herein discuss the implications of this work on ice nucleation and freezing processes.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 2010-2019"},"PeriodicalIF":4.3,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00411f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142337475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Differences in phytoplankton population vulnerability in response to chemical activity of mixtures†","authors":"Talles Bruno Oliveira dos Anjos, Quyen Nham, Sebastian Abel, Elin Lindehoff, Clare Bradshaw and Anna Sobek","doi":"10.1039/D4EM00249K","DOIUrl":"10.1039/D4EM00249K","url":null,"abstract":"<p >Hydrophobic organic contaminants (HOCs) affect phytoplankton at cellular to population levels, ultimately impacting communities and ecosystems. Baseline toxicants, such as some HOCs, predominantly partition to biological membranes and storage lipids. Predicting their toxic effects on phytoplankton populations therefore requires consideration beyond cell uptake and diffusion. Functional traits like lipid content and profile can offer insights into the diverse responses of phytoplankton populations exposed to HOCs. Our study investigated the vulnerability of five phytoplankton species populations to varying chemical activities of a mixture of polycyclic aromatic hydrocarbons (PAHs). Population vulnerability was assessed based on intrinsic sensitivities (toxicokinetic and toxicodynamic), and demography. Despite similar chemical activities in biota within the exposed algae, effects varied significantly. According to the chemical activity causing 50% of the growth inhibition (Ea<small>₅₀</small>), we found that the diatom <em>Phaeodactylum tricornutum</em> (Ea<small>₅₀</small> = 0.203) was the least affected by the chemical exposure and was also a species with low lipid content. In contrast, <em>Prymnesium parvum</em> (Ea<small>₅₀</small> = 0.072) and <em>Rhodomonas salina</em> (Ea<small>₅₀</small> = 0.08), both with high lipid content and high diversity of fatty acids in non-exposed samples, were more vulnerable to the chemical mixture. Moreover, the species <em>P. parvum</em>, <em>P. tricornutum</em>, and <em>Nannochloris</em> sp., displayed increased lipid production, evidenced as 5–10% increase in lipid fluorescence, after exposure to the chemical mixture. This lipid increase has the potential to alter the intrinsic sensitivity of the populations because storage lipids facilitate membrane repair, reconstitution and may, in the short-term, dilute contaminants within cells. Our study integrated principles of thermodynamics through the assessment of membrane saturation (<em>i.e.</em> chemical activity), and a lipid trait-based assessment to elucidate the differences in population vulnerability among phytoplankton species exposed to HOC mixtures.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 2062-2075"},"PeriodicalIF":4.3,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00249k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Improved prediction of PFAS partitioning with PPLFERs and QSPRs†","authors":"Trevor N. Brown, James M. Armitage, Alessandro Sangion and Jon A. Arnot","doi":"10.1039/D4EM00485J","DOIUrl":"10.1039/D4EM00485J","url":null,"abstract":"<p >Per- and polyfluoroalkyl substances (PFAS) are chemicals of high concern and are undergoing hazard and risk assessment worldwide. Reliable physicochemical property (PCP) data are fundamental to assessments. However, experimental PCP data for PFAS are limited and property prediction tools such as quantitative structure–property relationships (QSPRs) therefore have poor predictive power for PFAS. New experimental data from Endo 2023 are used to improve QSPRs for predicting poly-parameter linear free energy relationship (PPLFER) descriptors for calculating water solubility (<em>S</em><small>_W</small>), vapor pressure (VP) and the octanol–water (<em>K</em><small>_OW</small>), octanol–air (<em>K</em><small>_OA</small>) and air–water (<em>K</em><small>_AW</small>) partition ratios. The new experimental data are only for neutral PFAS, and the QSPRs are only applicable to neutral chemicals. A key PPLFER descriptor for PFAS is the molar volume and this work compares different versions and makes recommendations for obtaining the best PCP predictions. The new models are included in the freely available IFSQSAR package (version 1.1.1), and property predictions are compared to those from the previous IFSQSAR (version 1.1.0) and from QSPRs in the US EPA's EPI Suite (version 4.11) and OPERA (version 2.9) models. The results from the new IFSQSAR models show improvements for predicting PFAS PCPs. The root mean squared error (RMSE) for predicting log <em>K</em><small>_OW</small><em>versus</em> expected values from quantum chemical calculations was reduced by approximately 1 log unit whereas the RMSE for predicting log <em>K</em><small>_AW</small> and log <em>K</em><small>_OA</small> was reduced by 0.2 log units. IFSQSAR v.1.1.1 has an RMSE one or more log units lower than predictions from OPERA and EPI Suite when compared to expected values of log <em>K</em><small>_OW</small>, log <em>K</em><small>_AW</small> and log <em>K</em><small>_OA</small> for PFAS, except for EPI Suite predictions for log <em>K</em><small>_OW</small> which have a comparable RMSE. Recommendations for future experimental work for PPLFER descriptors for PFAS and future research to improve PCP predictions for PFAS are presented.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 1986-1998"},"PeriodicalIF":4.3,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00485j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142337474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Critical insights into data curation and label noise for accurate prediction of aerobic biodegradability of organic chemicals†","authors":"Paulina Körner, Juliane Glüge, Stefan Glüge and Martin Scheringer","doi":"10.1039/D4EM00431K","DOIUrl":"10.1039/D4EM00431K","url":null,"abstract":"<p >The focus of this work is to enhance state-of-the-art Machine Learning (ML) models that can predict the aerobic biodegradability of organic chemicals through a data-centric approach. To do that, an already existing dataset that was previously used to train ML models was analyzed for mismatching chemical identifiers and data leakage between test and training set and the detected errors were corrected. Chemicals with high variance between study results were removed and an XGBoost was trained on the dataset. Despite extensive data curation, only marginal improvement was achieved in the classification model's performance. This was attributed to three potential reasons: (1) a significant number of data labels were noisy, (2) the features could not sufficiently represent the chemicals, and/or (3) the model struggled to learn and generalize effectively. All three potential reasons were examined and point (1) seemed to be the most decisive one that prevented the model from generating more accurate results. Removing data points with possibly noisy labels by performing label noise filtering using two other predictive models increased the classification model's balanced accuracy from 80.9% to 94.2%. The new classifier is therefore better than any previously developed classification model for ready biodegradation. The examination of the key characteristics (molecular weight of the substances, proportion of halogens present and distribution of degradation labels) and the applicability domain indicate that no/not a large share of difficult-to-learn substances has been removed in the label noise filtering, meaning that the final model is still very robust.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1780-1795"},"PeriodicalIF":4.3,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00431k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142337473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}

{"title":"Formation of atmospheric molecular clusters containing nitric acid with ammonia, methylamine, and dimethylamine†","authors":"Dong-Ping Chen, Wen Ma, Chun-Hong Yang, Ming Li, Zhao-Zhen Zhou, Yang Zhang, Xi-Cun Wang and Zheng-Jun Quan","doi":"10.1039/D4EM00330F","DOIUrl":"10.1039/D4EM00330F","url":null,"abstract":"<p >This study investigates the formation of atmospheric molecular clusters containing ammonia (NH<small>₃</small>, A), methylamine (CH<small>₃</small>NH<small>₂</small>, MA), or dimethylamine (CH<small>₃</small>NHCH<small>₃</small>, DMA) with nitric acid (HNO<small>₃</small>, NA) using quantum mechanics. The Atmospheric Cluster Dynamic Code (ACDC) was employed to simulate the total evaporation rate, formation rate, and growth pathways of three types of clusters under dry and hydrated conditions. This study evaluates the enhancing potential of A/MA/DMA for NA-based new particle formation (NPF) at parts per trillion (ppt) levels. The results indicate that A/MA/DMA can enhance NA-based NPF at high nitric acid concentrations and low temperatures in the atmosphere. The enhancing potential of MA is weaker than that of DMA but stronger than that of A. Cluster growth predominantly follows the lowest free energy pathways on the acid–base grid, with the formation of initial acid–base dimers (NA)(A), (NA)(MA), and (NA)(DMA) being crucial. Hydration influences the evaporation rate and formation rate of clusters, especially for initial clusters. When the humidity is at 100%, the formation rate for NA–A, NA–MA, and NA–DMA clusters can increase by approximately 10<small>⁹</small>, 10<small>⁷</small>, and 10<small>⁴</small>-fold compared to the corresponding unhydrated clusters, respectively. These results highlight the significance of nitric acid nucleation in NPF events in low-temperature, high-humidity atmospheres, particularly in regions like China with significant automobile exhaust pollution.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 2036-2050"},"PeriodicalIF":4.3,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142398744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Modeling of mercury deposition in India: evaluating emission inventories and anthropogenic impacts†","authors":"Chakradhar Reddy Malasani, Basudev Swain, Ankit Patel, Yaswanth Pulipatti, Nidhi L. Anchan, Amit Sharma, Marco Vountas, Pengfei Liu and Sachin S. Gunthe","doi":"10.1039/D4EM00324A","DOIUrl":"10.1039/D4EM00324A","url":null,"abstract":"<p >Mercury (Hg), a ubiquitous atmospheric trace metal posing serious health risks, originates from natural and anthropogenic sources. India, the world's second-largest Hg emitter and a signatory to the Minamata Convention, is committed to reducing these emissions. However, critical gaps exist in our understanding of the spatial and temporal distribution of Hg across the vast Indian subcontinent due to limited observational data. This study addresses this gap by employing the GEOS-Chem model with various emission inventories (UNEP2010, WHET, EDGAR, STREETS, and UNEP2015) to simulate Hg variability across the Asian domain, with a specific focus on India from 2013 to 2017. Model performance was evaluated using ground-based GMOS observations and available literature data. Emission inventory performance varied across different observational stations. Hence, we employed ensemble results from all inventories. The maximum relative bias for Total Gaseous Mercury (TGM) and Gaseous Elemental Mercury (GEM; Hg<small>⁰</small>) concentrations is about ±20%, indicating simulations with sufficient accuracy. Total Hg wet deposition fluxes are highest over the Western Ghats and the Himalayan foothills due to higher rainfall. During the monsoon, the Hg wet deposition flux is about 65.4% of the annual wet deposition flux. Moreover, westerly winds cause higher wet deposition in summer over Northern and Eastern India. Total Hg dry deposition flux accounts for 72–74% of total deposition over India. Hg<small>⁰</small> dry deposition fluxes are higher over Eastern India, which correlates strongly with the leaf area index. Excluding Indian anthropogenic emissions from the model simulations resulted in a substantial decrease (21.9% and 33.5%) in wet and total Hg deposition fluxes, highlighting the dominant role of human activities in Hg pollution in India.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 11","pages":" 1999-2009"},"PeriodicalIF":4.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00324a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}