Environmental Science: Processes & Impacts最新文献

{"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}

{"title":"Assessment of occurrence, source appointment, and ecological risks of pharmaceuticals and personal care products in the water–sediment interface of Qiantang River in the Hangzhou region†","authors":"Yang Wan, Ziming Wang, Kaiping Xu, Wei Wang, Pengcheng Yao and Aiju You","doi":"10.1039/D4EM00355A","DOIUrl":"10.1039/D4EM00355A","url":null,"abstract":"<p >Pharmaceuticals and personal care products (PPCPs) have received global attention owing to their potential risks to human health and the ecological environment. However, limited research has explored the occurrence and ecological risks of PPCPs in the Qiantang River (QTR). QTR, the largest water system in Zhejiang Province, China, is significantly influenced by human activities. This study investigated the occurrence, distribution, and ecological risks of 10 types of PPCPs in both surface water and sediment within QTR. The findings revealed that the concentrations of PPCPs detected in surface water ranged from 81.26 to 149.45 ng L<small>⁻¹</small> during the wet season (April) and from 98.66 to 198.55 ng L<small>⁻¹</small> during the dry season (September). Moreover, in the sediments, PPCP concentration ranged from 63.24 to 80.66 and 72.54 to 75.06 ng per g dw during both wet and dry seasons, respectively. Among the selected PPCPs, triclosan (TCS) exhibited the highest concentration across, different phases and seasons, followed by benzotriazole in surface water. The analysis of sediment–water equilibrium distribution indicated that the diffusion tendency of PPCPs was closely correlated with their molecular weights. Particularly, TCS exhibited dynamic equilibrium between water and sediment. Principal component analysis and positive matrix factorization model results indicated similar pollution sources for the detected PPCPs. The dominant sources of the detected PPCPs were identified as wastewater of electroplating enterprises, discharge from wastewater treatment plants, and domestic sewage. The ecological risk assessment based on the risk quotient method revealed that TCS with the highest detected concentration posed a high risk in surface water and a low risk in sediment across all sampling sites. However, other detected PPCPs showed either no or low risks. Additionally, PPCPs showed a higher ecological risk during the dry season than during the wet season.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1887-1897"},"PeriodicalIF":4.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256057","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":"Pollution characteristics and risk assessment of endocrine-disrupting chemicals in surface water of national (freshwater) aquatic germplasm resource reserves in Guangdong Province†","authors":"Tao Zhou, Jie Li, Weizhen Zhang, Yanyi Zeng, Yuan Gao, Haiyan Li, Wanling Yang, Yongzhan Mai, Qianfu Liu, Caiqin Hu and Chao Wang","doi":"10.1039/D4EM00425F","DOIUrl":"10.1039/D4EM00425F","url":null,"abstract":"<p >The distribution, composition, and risk assessment of 8 EDCs in the surface water of 14 national aquatic germplasm resource reserves (freshwater) were investigated during dry and wet seasons. Bisphenol A (BPA), nonylphenol (NP), and octylphenol (OP) were the main contributors of the 8 EDCs. The concentrations of phenolic pollutants in surface water during the dry season were higher than those in the wet season. However, no significant seasonal differences were found among the steroid hormones. According to the evaluation of estrogenic activity (EEQ &gt; 1.0), E2 and EE2 were the main contributors to estrogenic activity. EDC mixtures posed a higher risk to crustaceans and fish (RQ &gt; 1.0) and a moderate to high risk to algae (RQ &gt; 0.1). Fish were the most sensitive aquatic organisms. In the study areas, EE2, E1, BPA, NP, and E2 had a higher risk than the other three compounds and should be controlled as a priority.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1898-1911"},"PeriodicalIF":4.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256059","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":"Storms mobilize organophosphate esters, bisphenols, PFASs, and vehicle-derived contaminants to San Francisco Bay watersheds†","authors":"Katherine T. Peter, Alicia Gilbreath, Melissa Gonzalez, Zhenyu Tian, Adam Wong, Don Yee, Ezra L. Miller, Pedro M. Avellaneda, Da Chen, Andrew Patterson, Nicole Fitzgerald, Christopher P. Higgins, Edward P. Kolodziej and Rebecca Sutton","doi":"10.1039/D4EM00117F","DOIUrl":"10.1039/D4EM00117F","url":null,"abstract":"<p >In urban to peri-urban watersheds such as those surrounding San Francisco Bay, stormwater runoff is a major pathway by which contaminants enter aquatic ecosystems. We evaluated the occurrence of 154 organic contaminants <em>via</em> liquid chromatography coupled to tandem mass spectrometry, including organophosphate esters (OPEs), bisphenols, per- and polyfluoroalkyl substances (PFASs), and a suite of novel urban stormwater tracers (SWCECs; <em>i.e.</em>, vehicle-derived chemicals, pesticides, pharmaceuticals/personal care products, benzothiazoles/benzotriazoles). Time-averaged composite sampling focused on storms in highly developed watersheds over four wet seasons, with complementary sampling in less-urban reference watersheds, near-shore estuarine sites, and the open Bay. Of the targeted contaminants, 68 (21 SWCECs, 29 OPEs, 3 bisphenols, 15 PFASs) were detected in ≥10 of 26 urban stormwater samples. Median concentrations exceeded 500 ng L<small>⁻¹</small> for 1,3-diphenylguanidine, hexa(methoxymethyl)melamine, and caffeine, and exceeded 300 ng L<small>⁻¹</small> for 2-hydroxy-benzothiazole, 5-methyl-1<em>H</em>-benzotriazole, pentachlorophenol, and tris(2-butoxyethyl) phosphate. Median individual PFAS concentrations were &lt;10 ng L<small>⁻¹</small>, with highest concentrations for PFHxA (180 ng L<small>⁻¹</small>), PFOA (110 ng L<small>⁻¹</small>), and PFOS (81 ng L<small>⁻¹</small>). In six of eight urban stormwater samples analyzed for 6PPD-quinone (a tire rubber-derived transformation product), concentrations exceeded coho salmon acute toxicity thresholds, suggesting (sub)lethal impacts for sensitive species. Observed concentrations were generally significantly higher in highly developed watersheds relative to reference watersheds, but not statistically different in near-shore estuarine sites, suggesting substantial transient exposure potential at stormwater outfalls or creek outflows. Results emphasized the role of stormwater in contaminant transport, the importance of vehicles/roadways as contaminant sources, and the value of monitoring broad multi-analyte contaminant suites to enable comprehensive source and toxicity evaluations.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1760-1779"},"PeriodicalIF":4.3,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00117f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142256058","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":"Exploring the variability of PFAS in urban sewage: a comparison of emissions in commercial versus municipal urban areas†","authors":"Krlovic N., Saracevic E., Derx J., Gundacker C., Krampe J., Kreuzinger N., Zessner M. and Zoboli O.","doi":"10.1039/D4EM00415A","DOIUrl":"10.1039/D4EM00415A","url":null,"abstract":"<p >Per- and polyfluoroalkyl substances (PFAS) are recognized for their persistence and ubiquitous occurrence in different environmental compartments. Conventional wastewater treatment plants (WWTPs) cannot effectively remove PFAS from wastewater, and a better understanding of the occurrence and sources of PFAS in this medium would enable effective source abatement. We compared sewage from urban areas exhibiting differentiating characteristics with respect to activities in their catchments. These included a sewer that serves primarily a municipal area, with no commercial activities involving PFAS emissions being identified, another sewer with a strong influence of commercial activities potentially related to PFAS emissions, and the influent of the whole city sewage network. The year-long monitoring campaign consisted of flow-proportional, monthly composite samples and targeted analysis of 29 PFAS compounds. Principal component analysis was used to investigate the relationships between selected PFAS and standard water quality parameters such as ammonium, a known tracer of urine and thus of typical municipal wastewater. Notable findings were seen for PFOS and 6:2 FTS, whose concentrations were most negatively correlated with ammonium. Ammonium concentration data allowed for a normalized per-person median load calculation, which resulted in loads of the observed PFAS ranging from below 0.4 up to 4.7 μg per person per day. Both the commercial area sewer and the city influent exhibited significantly higher (<em>p</em> &lt; 0.05) median loads (&gt;0.9 μg per person per day) in the case of 6:2 FTS and PFOS, compared to the municipal sewer (&lt;0.6 μg per person per day). No statistically significant difference was found for other compounds, such as PFBA, PFHxA, PFOA, and PFHxS. We argue that this approach demonstrates that PFAS can differ in speciation and quantity within an urban wastewater setting, and consideration of both municipal and commercial activities is needed for a proper understanding of sources and emission pathways within the urban environment.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1868-1878"},"PeriodicalIF":4.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/em/d4em00415a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142197919","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":"The impact of surfaces on indoor air chemistry following cooking and cleaning","authors":"Ellen Harding-Smith, Helen L. Davies, Catherine O'Leary, Ruth Winkless, Marvin Shaw, Terry Dillon, Benjamin Jones, Nicola Carslaw","doi":"10.1039/d4em00410h","DOIUrl":"https://doi.org/10.1039/d4em00410h","url":null,"abstract":"Cooking and cleaning are common sources of indoor air pollutants, including volatile organic compounds (VOCs). The chemical fate of VOCs indoors is determined by both gas-phase and multi-phase chemistry, and can result in the formation of potentially hazardous secondary pollutants. Chemical interactions at the gas-surface boundary play an important role in indoor environments due to the characteristically high surface area to volume ratios (SAVs). This study first characterises the VOC emissions from a typical cooking and cleaning activity in a semi-realistic domestic kitchen, using real-time measurements. While cooking emitted a larger amount of VOCs overall, both cooking and cleaning were sources of chemically reactive monoterpenes (peak mixing ratios 7 ppb and 2 ppb, respectively). Chemical processing of the VOC emissions from sequential cooking and cleaning activities was then simulated in a kitchen using a detailed chemical model. Results showed that ozone (O<small>₃</small>) deposition was most effective onto plastic and soft furnishings, while wooden surfaces were the most effective at producing formaldehyde following multi-phase chemistry. Subsequent modelling of cooking and cleaning emissions using a range of measured kitchen SAVs revealed that indoor oxidant levels and the subsequent chemistry, are strongly influenced by the total and material-specific SAV of the room. O<small>₃</small> mixing ratios ranged from 1.3–7.8 ppb across 9 simulated kitchens, with higher concentrations of secondary pollutants observed at higher O<small>₃</small> concentration. Increased room volume, decreased total SAV, decreased SAVs of plastic and soft furnishings, and increased wood SAV contributed to elevated formaldehyde and total peroxyacetyl nitrates (PANs) mixing ratios, of up to 1548 ppt and 643 ppt, respectively, following cooking and cleaning. Therefore, the size and material composition of indoor environments has the potential to impact the chemical processing of VOC emissions from common occupant activities.","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":"72 1","pages":""},"PeriodicalIF":5.5,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142197920","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":"Influence of tritium exposure route on vegetation types at the Savannah River Site†","authors":"Martine C. Duff, Elizabeth A. Pettitt and Holly VerMeulen","doi":"10.1039/D4EM00311J","DOIUrl":"10.1039/D4EM00311J","url":null,"abstract":"<p >Plant, soil, water, and other media from various locations at the Savannah River Site were measured for total tritium (T) content and T speciation to characterize T in these areas, as well as investigate its uptake behavior and the transport of T species in these media. This characterization included the isolation and measurement of T in tritiated water (HTO), and (when possible) exchangeable organic bound T (E-OBT) and non-exchangeable organic bound T (NE-OBT). Two areas of interest were investigated: (1) a holding pond with T-contaminated water and (2) open basins or streams with low to background levels of T. Water in the holding pond is used to irrigate forest plots in the local area as a T remediation approach. This study compares the analytical data for water, soil/sediment, plants, and lichens from these locations. The results indicate that the behavior of T in plants from these areas can be a function of one or more of the following: seasonal precipitation, the plant's primary route of access to the T-contamination (such as water uptake through the root <em>vs.</em> shoot), plant physical location (relative to T-contaminated water sources), plant rooting depth, pond water level, and plant height above the ground. Total T concentrations were lowest in the un-irrigated forest plants, followed by irrigated forest plants, shallow rooting plants near the pond, deep rooting plants further from the pond, and then water-saturated plants. The OBT:HTO and NE-OBT:E-OBT ratios were always greater for plants from irrigated forest plots compared to those from the holding pond.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" 10","pages":" 1736-1747"},"PeriodicalIF":4.3,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142197923","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}