Micro- and nano-plastics (M/NPs) potentially leach from plastic wrapping into food and beverages. However, the risks of ingested M/NPs to human intestinal health remain unclear. This study aimed to determine the potential risks and mechanisms of PS-M/NPs using a human intestinal epithelial in vitro model and to explore protective measures to reduce these risks. The results showed that polystyrene (PS) M/NPs exhibited size-dependent cytotoxicity (3 μm < 0.3 μm < 80 nm < 20 nm). Additionally, by measuring intracellular reactive oxygen species (ROS) production after exposure to PS-M/NPs and the elimination of ROS by N-acetyl-L-cysteine, we identified oxidative stress as a mechanism of PS-M/NP-induced cytotoxicity. Hazard quotients calculated from the study indicated that the risks of M/NPs derived from plastic teabags exceeded the margin of safety, suggesting that ingested M/NPs potentially pose a risk to human intestinal health. Furthermore, this study found that catechins can reduce the adverse effects of M/NPs, so we propose that drinking tea may offer a protective effect against the harm of M/NPs on the intestinal system.
{"title":"Assessment of the cytotoxicity micro- and nano-plastic on human intestinal Caco-2 cells and the protective effects of catechin.","authors":"Xiaoxia Wang, Zhongneng Yang, Xiao-Min Ren, Zhenghuan Zhang, Huan He, Xuejun Pan","doi":"10.1039/d4em00408f","DOIUrl":"https://doi.org/10.1039/d4em00408f","url":null,"abstract":"<p><p>Micro- and nano-plastics (M/NPs) potentially leach from plastic wrapping into food and beverages. However, the risks of ingested M/NPs to human intestinal health remain unclear. This study aimed to determine the potential risks and mechanisms of PS-M/NPs using a human intestinal epithelial <i>in vitro</i> model and to explore protective measures to reduce these risks. The results showed that polystyrene (PS) M/NPs exhibited size-dependent cytotoxicity (3 μm < 0.3 μm < 80 nm < 20 nm). Additionally, by measuring intracellular reactive oxygen species (ROS) production after exposure to PS-M/NPs and the elimination of ROS by <i>N</i>-acetyl-L-cysteine, we identified oxidative stress as a mechanism of PS-M/NP-induced cytotoxicity. Hazard quotients calculated from the study indicated that the risks of M/NPs derived from plastic teabags exceeded the margin of safety, suggesting that ingested M/NPs potentially pose a risk to human intestinal health. Furthermore, this study found that catechins can reduce the adverse effects of M/NPs, so we propose that drinking tea may offer a protective effect against the harm of M/NPs on the intestinal system.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453617","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}
Carlos Silva, Etelvina Figueira, Diana Matos, Carina Sá, Tânia Vidal, Fernando José Mendes Gonçalves, Nelson Abrantes, Joana Luísa Pereira
Periphyton is frequently used in the evaluation of the ecological status of aquatic ecosystems using diatoms as a proxy. However, periphyton has a particularity, the production of extracellular polymeric substances (EPS), which might play a protective role against exposure to harmful environmental contaminants. Effluents originating in wastewater treatment plants (WWTPs) constitute some of the most complex mixtures of contaminants, to which aquatic ecosystems are frequently exposed, often containing tens to hundreds of different chemicals. In such challenging scenarios, a putative protective role of EPS may obscure the bioindicator value of diatoms. To address this problem, we sampled periphyton upstream and downstream of the effluent outfall from three different WWTPs, quantifying EPS production and simultaneously evaluating general stress responses in the community (protein and sugar content, photosynthetic pigments, antioxidant enzyme activity and oxidative damage). By combining these endpoints with a characterization of the sediments of the riverine systems receiving the effluents made in a previous study (metals, polycyclic aromatic hydrocarbons, pharmaceuticals and personal care products), we aimed to elucidate whether effluent contaminants trigger negative effects, which may be mitigated by EPS layers protecting the communities. Our results indicated that under a comparatively milder contamination burden, EPS production is enhanced in samples collected downstream of the effluent outfall; under a higher contamination burden, EPS production is hampered. Stress-coping mechanisms were activated by environmental contaminants, including the antioxidant defense, particularly through catalase and superoxide dismutase activity. The findings support the generally assumed protective effect of EPS, but also suggest that EPS production depends on the contamination burden and that protective effects should be in place under specific scenarios of, for example, relatively low contamination levels. Overall, the integrative approach used in this study contributes to a better understanding of the complex interplay of interactions between effluent-driven contamination and thriving periphytic communities inhabiting recipient waterways, including evolved protection mechanisms.
{"title":"Assessment of extracellular polymeric substances production and antioxidant defences in periphytic communities exposed to effluent contaminants.","authors":"Carlos Silva, Etelvina Figueira, Diana Matos, Carina Sá, Tânia Vidal, Fernando José Mendes Gonçalves, Nelson Abrantes, Joana Luísa Pereira","doi":"10.1039/d4em00446a","DOIUrl":"https://doi.org/10.1039/d4em00446a","url":null,"abstract":"<p><p>Periphyton is frequently used in the evaluation of the ecological status of aquatic ecosystems using diatoms as a proxy. However, periphyton has a particularity, the production of extracellular polymeric substances (EPS), which might play a protective role against exposure to harmful environmental contaminants. Effluents originating in wastewater treatment plants (WWTPs) constitute some of the most complex mixtures of contaminants, to which aquatic ecosystems are frequently exposed, often containing tens to hundreds of different chemicals. In such challenging scenarios, a putative protective role of EPS may obscure the bioindicator value of diatoms. To address this problem, we sampled periphyton upstream and downstream of the effluent outfall from three different WWTPs, quantifying EPS production and simultaneously evaluating general stress responses in the community (protein and sugar content, photosynthetic pigments, antioxidant enzyme activity and oxidative damage). By combining these endpoints with a characterization of the sediments of the riverine systems receiving the effluents made in a previous study (metals, polycyclic aromatic hydrocarbons, pharmaceuticals and personal care products), we aimed to elucidate whether effluent contaminants trigger negative effects, which may be mitigated by EPS layers protecting the communities. Our results indicated that under a comparatively milder contamination burden, EPS production is enhanced in samples collected downstream of the effluent outfall; under a higher contamination burden, EPS production is hampered. Stress-coping mechanisms were activated by environmental contaminants, including the antioxidant defense, particularly through catalase and superoxide dismutase activity. The findings support the generally assumed protective effect of EPS, but also suggest that EPS production depends on the contamination burden and that protective effects should be in place under specific scenarios of, for example, relatively low contamination levels. Overall, the integrative approach used in this study contributes to a better understanding of the complex interplay of interactions between effluent-driven contamination and thriving periphytic communities inhabiting recipient waterways, including evolved protection mechanisms.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453611","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}
Danushika C Manatunga, Madushika Sewwandi, Kalani Imalka Perera, Methmini Dilhara Jayarathna, Dinusha L Peramune, Rohan S Dassanayake, Sammani Ramanayaka, Meththika Vithanage
Plasticizers, essential additives for enhancing plastic properties, have emerged as significant environmental and health concerns due to their persistence and widespread use. This study provides an in-depth exploration of plasticizers, focusing on their types, structures, properties, production methods, environmental distribution, and associated risks. The findings reveal that petroleum-based phthalates, particularly di-(2-ethylhexyl) phthalate (DEHP), are prevalent in aquatic and terrestrial environments, primarily due to the gradual degradation of plastic polymers. In the analysis of 39 studies on water contamination during the period of 2022-2023, only 22 works could be extracted due to insufficient details on the numerical value of plasticizer concentrations. Similarly, soil and sediment contamination studies were fewer, with only 11 studies focusing on sediments. These studies reveal that high plasticizer concentrations, notably in industrial and urban areas, often exceed recommended environmental limits, posing risks to ecological integrity and human health through bioaccumulation. Bioaccumulation of these compounds in soil and water could negatively affect the microbial communities, nutrient cycling, and could destabilize the overall ecological integrity. Concerns about their direct uptake by plants and potential risks to human health and food safety are highlighted in this study due to the high concentrations exceeding the threshold values. The review evaluates current treatment technologies, including metal-organic frameworks, electrochemical systems, multi-walled carbon nanotubes, and microbial degradation, noting their potential and challenges related to cost and energy consumption. It underscores the need for improved detection protocols, cost-effective treatments, stricter regulations, public awareness, and collaborative research to mitigate the adverse impacts of plasticizers on ecosystems and human health.
{"title":"Plasticizers: distribution and impact in aquatic and terrestrial environments.","authors":"Danushika C Manatunga, Madushika Sewwandi, Kalani Imalka Perera, Methmini Dilhara Jayarathna, Dinusha L Peramune, Rohan S Dassanayake, Sammani Ramanayaka, Meththika Vithanage","doi":"10.1039/d4em00317a","DOIUrl":"https://doi.org/10.1039/d4em00317a","url":null,"abstract":"<p><p>Plasticizers, essential additives for enhancing plastic properties, have emerged as significant environmental and health concerns due to their persistence and widespread use. This study provides an in-depth exploration of plasticizers, focusing on their types, structures, properties, production methods, environmental distribution, and associated risks. The findings reveal that petroleum-based phthalates, particularly di-(2-ethylhexyl) phthalate (DEHP), are prevalent in aquatic and terrestrial environments, primarily due to the gradual degradation of plastic polymers. In the analysis of 39 studies on water contamination during the period of 2022-2023, only 22 works could be extracted due to insufficient details on the numerical value of plasticizer concentrations. Similarly, soil and sediment contamination studies were fewer, with only 11 studies focusing on sediments. These studies reveal that high plasticizer concentrations, notably in industrial and urban areas, often exceed recommended environmental limits, posing risks to ecological integrity and human health through bioaccumulation. Bioaccumulation of these compounds in soil and water could negatively affect the microbial communities, nutrient cycling, and could destabilize the overall ecological integrity. Concerns about their direct uptake by plants and potential risks to human health and food safety are highlighted in this study due to the high concentrations exceeding the threshold values. The review evaluates current treatment technologies, including metal-organic frameworks, electrochemical systems, multi-walled carbon nanotubes, and microbial degradation, noting their potential and challenges related to cost and energy consumption. It underscores the need for improved detection protocols, cost-effective treatments, stricter regulations, public awareness, and collaborative research to mitigate the adverse impacts of plasticizers on ecosystems and human health.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142453619","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}
Talles Bruno Oliveira Dos Anjos, Quyen Nham, Sebastian Abel, Elin Lindehoff, Clare Bradshaw, Anna Sobek
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 (Ea50), we found that the diatom Phaeodactylum tricornutum (Ea50 = 0.203) was the least affected by the chemical exposure and was also a species with low lipid content. In contrast, Prymnesium parvum (Ea50 = 0.072) and Rhodomonas salina (Ea50 = 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 P. parvum, P. tricornutum, and Nannochloris 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 (i.e. chemical activity), and a lipid trait-based assessment to elucidate the differences in population vulnerability among phytoplankton species exposed to HOC mixtures.
{"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, Anna Sobek","doi":"10.1039/d4em00249k","DOIUrl":"https://doi.org/10.1039/d4em00249k","url":null,"abstract":"<p><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<sub>50</sub>), we found that the diatom <i>Phaeodactylum tricornutum</i> (Ea<sub>50</sub> = 0.203) was the least affected by the chemical exposure and was also a species with low lipid content. In contrast, <i>Prymnesium parvum</i> (Ea<sub>50</sub> = 0.072) and <i>Rhodomonas salina</i> (Ea<sub>50</sub> = 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 <i>P. parvum</i>, <i>P. tricornutum</i>, and <i>Nannochloris</i> 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 (<i>i.e.</i> 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":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","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":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dong-Ping Chen, Wen Ma, Chun-Hong Yang, Ming Li, Zhao-Zhen Zhou, Yang Zhang, Xi-Cun Wang, Zheng-Jun Quan
This study investigates the formation of atmospheric molecular clusters containing ammonia (NH3, A), methylamine (CH3NH2, MA), or dimethylamine (CH3NHCH3, DMA) with nitric acid (HNO3, 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 109, 107, and 104-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.
{"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, Zheng-Jun Quan","doi":"10.1039/d4em00330f","DOIUrl":"https://doi.org/10.1039/d4em00330f","url":null,"abstract":"<p><p>This study investigates the formation of atmospheric molecular clusters containing ammonia (NH<sub>3</sub>, A), methylamine (CH<sub>3</sub>NH<sub>2</sub>, MA), or dimethylamine (CH<sub>3</sub>NHCH<sub>3</sub>, DMA) with nitric acid (HNO<sub>3</sub>, 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<sup>9</sup>, 10<sup>7</sup>, and 10<sup>4</sup>-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":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-11","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}
Paul N Diagboya, Bamidele I Olu-Owolabi, Rolf-Alexander Düring
The pesticide glyphosate has contributed immensely to the ease of farming and high yields. However, the ever-increasing environmental input of pesticides is of particular interest due to several unintended effects on non-target organisms. In soil, the sorption, transport, possible uptake, and effect on plant growth are still not well understood, and much so for the sub-Sahara. Sorption processes are contingent on the soil composition, characteristics, and ambient conditions, and these are becoming increasingly affected by climate change in a way that may alter pesticide fate. Hence, representative sub-Saharan whole soil (WS) treated to eliminate organic matter (OMR) and iron oxides (IOR) was employed to ascertain the contributions of these major constituents to glyphosate sorption processes, as well as ascertain the effect of glyphosate in soil on the growth of Talinum triangulare-waterleaf. Glyphosate sorption for all treatments was rapid with equilibrium at around 720 min. The sorption decreased as pH increased, and was concentration-dependent, gradually increasing with glyphosate concentration. The process was endothermic, and sorption data were better described by the fractal pseudo-second-order and Freundlich adsorption isotherm models, suggesting a complex interplay of interactive sorption forces. The IOR sample (with iron oxide depleted but organic matter intact) exhibited higher sorption than the OMR and WS, highlighting the contribution of organic matter in glyphosate sorption. Hysteresis was high for all samples and increased with temperature. Considering the unregulated usage of glyphosate in the sub-Sahara, the poor sorption, especially in treated soils, observed in this study suggests a high possibility of glyphosate leaching into the aquifer and poisoning of this water source, while the high hysteresis implied the bio-availability of glyphosate in surface soil for plant absorption, hence affecting growth; as confirmed in the waterleaf growth study where growth in the organic-matter/iron-oxide-depleted soils was substantially stunted. Hence, glyphosate affects waterleaf growth, especially in organic-matter/iron-oxide-depleted soils.
{"title":"Exploring the interactions of glyphosate in soil: the sorption scenario upon soil depletion and effect on waterleaf (<i>Talinum triangulare</i>) growth.","authors":"Paul N Diagboya, Bamidele I Olu-Owolabi, Rolf-Alexander Düring","doi":"10.1039/d4em00433g","DOIUrl":"https://doi.org/10.1039/d4em00433g","url":null,"abstract":"<p><p>The pesticide glyphosate has contributed immensely to the ease of farming and high yields. However, the ever-increasing environmental input of pesticides is of particular interest due to several unintended effects on non-target organisms. In soil, the sorption, transport, possible uptake, and effect on plant growth are still not well understood, and much so for the sub-Sahara. Sorption processes are contingent on the soil composition, characteristics, and ambient conditions, and these are becoming increasingly affected by climate change in a way that may alter pesticide fate. Hence, representative sub-Saharan whole soil (WS) treated to eliminate organic matter (OMR) and iron oxides (IOR) was employed to ascertain the contributions of these major constituents to glyphosate sorption processes, as well as ascertain the effect of glyphosate in soil on the growth of <i>Talinum triangulare</i>-waterleaf. Glyphosate sorption for all treatments was rapid with equilibrium at around 720 min. The sorption decreased as pH increased, and was concentration-dependent, gradually increasing with glyphosate concentration. The process was endothermic, and sorption data were better described by the fractal pseudo-second-order and Freundlich adsorption isotherm models, suggesting a complex interplay of interactive sorption forces. The IOR sample (with iron oxide depleted but organic matter intact) exhibited higher sorption than the OMR and WS, highlighting the contribution of organic matter in glyphosate sorption. Hysteresis was high for all samples and increased with temperature. Considering the unregulated usage of glyphosate in the sub-Sahara, the poor sorption, especially in treated soils, observed in this study suggests a high possibility of glyphosate leaching into the aquifer and poisoning of this water source, while the high hysteresis implied the bio-availability of glyphosate in surface soil for plant absorption, hence affecting growth; as confirmed in the waterleaf growth study where growth in the organic-matter/iron-oxide-depleted soils was substantially stunted. Hence, glyphosate affects waterleaf growth, especially in organic-matter/iron-oxide-depleted soils.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142386447","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}
Marc Webb, Glenn Morrison, Karsten Baumann, Jienan Li, Jenna C Ditto, Han N Huynh, Jie Yu, Kathryn Mayer, Liora Mael, Marina E Vance, Delphine K Farmer, Jonathan Abbatt, Dustin Poppendieck, Barbara J Turpin
Previous time-integrated (2 h to 4 h) measurements show that total gas-phase water-soluble organic carbon (WSOCg) is 10 to 20 times higher inside homes compared to outside. However, concentration dynamics of WSOCg and total particle phase WSOC (WSOCp)-are not well understood. During the Chemical Assessment of Surfaces and Air (CASA) experiment, we measured concentration dynamics of WSOCg and WSOCp inside a residential test facility in the house background and during scripted activities. A total organic carbon (TOC) analyzer pulled alternately from a particle-into-liquid sampler (PILS) or a mist chamber (MC). WSOCg concentrations (215 ± 29 μg-C m-3) were generally 36× higher than WSOCp (6 ± 3 μg-C m-3) and 20× higher than outdoor levels. A building-specific emission factor (Ef) of 31 mg-C h-1 maintained the relatively high house WSOCg background, which was dominated by ethanol (46 μg-C m-3 to 82 μg-C m-3). When we opened the windows, WSOCg decayed slower (2.8 h-1) than the air change rate (21.2 h-1) and Ef increased (243 mg-C h-1). The response (increased Ef) suggests WSOCg concentrations are regulated by large near surface reservoirs rather than diffusion through surface materials. Cooking and ozone addition had a small impact on WSOC, whereas surface cleaning, volatile organic compound (VOC) additions, or wood smoke injections had significant impacts on WSOC concentrations. WSOCg concentration decay rates from these activities (0.4 h-1 to 4.0 h-1) were greater than the normal operating 0.24 h-1 air change rate, which is consistent with an important role for surface removal.
{"title":"Dynamics of residential indoor gas- and particle-phase water-soluble organic carbon: measurements during the CASA experiment.","authors":"Marc Webb, Glenn Morrison, Karsten Baumann, Jienan Li, Jenna C Ditto, Han N Huynh, Jie Yu, Kathryn Mayer, Liora Mael, Marina E Vance, Delphine K Farmer, Jonathan Abbatt, Dustin Poppendieck, Barbara J Turpin","doi":"10.1039/d4em00340c","DOIUrl":"10.1039/d4em00340c","url":null,"abstract":"<p><p>Previous time-integrated (2 h to 4 h) measurements show that total gas-phase water-soluble organic carbon (WSOC<sub>g</sub>) is 10 to 20 times higher inside homes compared to outside. However, concentration dynamics of WSOC<sub>g</sub> and total particle phase WSOC (WSOC<sub>p</sub>)-are not well understood. During the Chemical Assessment of Surfaces and Air (CASA) experiment, we measured concentration dynamics of WSOC<sub>g</sub> and WSOC<sub>p</sub> inside a residential test facility in the house background and during scripted activities. A total organic carbon (TOC) analyzer pulled alternately from a particle-into-liquid sampler (PILS) or a mist chamber (MC). WSOC<sub>g</sub> concentrations (215 ± 29 μg-C m<sup>-3</sup>) were generally 36× higher than WSOC<sub>p</sub> (6 ± 3 μg-C m<sup>-3</sup>) and 20× higher than outdoor levels. A building-specific emission factor (<i>E</i><sub>f</sub>) of 31 mg-C h<sup>-1</sup> maintained the relatively high house WSOC<sub>g</sub> background, which was dominated by ethanol (46 μg-C m<sup>-3</sup> to 82 μg-C m<sup>-3</sup>). When we opened the windows, WSOC<sub>g</sub> decayed slower (2.8 h<sup>-1</sup>) than the air change rate (21.2 h<sup>-1</sup>) and <i>E</i><sub>f</sub> increased (243 mg-C h<sup>-1</sup>). The response (increased <i>E</i><sub>f</sub>) suggests WSOC<sub>g</sub> concentrations are regulated by large near surface reservoirs rather than diffusion through surface materials. Cooking and ozone addition had a small impact on WSOC, whereas surface cleaning, volatile organic compound (VOC) additions, or wood smoke injections had significant impacts on WSOC concentrations. WSOC<sub>g</sub> concentration decay rates from these activities (0.4 h<sup>-1</sup> to 4.0 h<sup>-1</sup>) were greater than the normal operating 0.24 h<sup>-1</sup> air change rate, which is consistent with an important role for surface removal.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379531","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}
Ibukun Ola, Carsten Drebenstedt, Robert M Burgess, Lane Tidwell, Kim Anderson, Nils Hoth, Christoph Külls
In equilibrium-based passive sampling applications, the accuracy of estimating freely dissolved concentration (Cfree) of hydrophobic organic compounds (HOCs) relies on the passive sampler-water partition coefficient (KPS-W) values applied. The vast majority of KPS-W 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 (KPE-W) 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 KPE-W values were found to correlate strongly with a variety of molecular parameters (e.g., octanol-water partition coefficients (KOW), molecular weight (MW) and molecular volume (MVOL)). The effects of temperature and salinity on the magnitude of KPE-W 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 KPE-W 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 KPE-W 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 KOW), 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, KPE-W 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 KPE-W values were adjusted to 10 °C and 30 °C, the final freely dissolved concentrations (Cfree) 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 Cfree values for estimating exposure and adverse ecological effects.
{"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, Christoph Külls","doi":"10.1039/d4em00133h","DOIUrl":"https://doi.org/10.1039/d4em00133h","url":null,"abstract":"<p><p>In equilibrium-based passive sampling applications, the accuracy of estimating freely dissolved concentration (<i>C</i><sub>free</sub>) of hydrophobic organic compounds (HOCs) relies on the passive sampler-water partition coefficient (<i>K</i><sub>PS-W</sub>) values applied. The vast majority of <i>K</i><sub>PS-W</sub> 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 (<i>K</i><sub>PE-W</sub>) 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 <i>K</i><sub>PE-W</sub> values were found to correlate strongly with a variety of molecular parameters (<i>e.g.</i>, octanol-water partition coefficients (<i>K</i><sub>OW</sub>), molecular weight (MW) and molecular volume (<i>M</i><sub>VOL</sub>)). The effects of temperature and salinity on the magnitude of <i>K</i><sub>PE-W</sub> 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 <i>K</i><sub>PE-W</sub> 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 <i>K</i><sub>PE-W</sub> 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 <i>K</i><sub>OW</sub>), 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, <i>K</i><sub>PE-W</sub> 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 <i>K</i><sub>PE-W</sub> values were adjusted to 10 °C and 30 °C, the final freely dissolved concentrations (<i>C</i><sub>free</sub>) 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 <i>C</i><sub>free</sub> values for estimating exposure and adverse ecological effects.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":null,"pages":null},"PeriodicalIF":4.3,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","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":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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
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 PM2.5 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.
{"title":"Indoor air concentrations of PM<sub>2.5</sub> 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":"https://doi.org/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<sub>2.5</sub> 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<sup>-3</sup>), while median PFBA concentrations (3.6 pg m<sup>-3</sup>; 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":null,"pages":null},"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}
Juliane Glüge, Katharina Breuer, Armin Hafner, Christian Vering, Dirk Müller, Ian T Cousins, Rainer Lohmann, Gretta Goldenman, Martin Scheringer
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 CO2 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.
{"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, Martin Scheringer","doi":"10.1039/d4em00444b","DOIUrl":"10.1039/d4em00444b","url":null,"abstract":"<p><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<sub>2</sub> 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":null,"pages":null},"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}