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Integrated Environmental Assessment and... Sep 2023Bioaccumulation assessments conducted by regulatory agencies worldwide use a variety of methods, types of data, metrics, and categorization criteria. Lines of evidence...
Bioaccumulation assessments conducted by regulatory agencies worldwide use a variety of methods, types of data, metrics, and categorization criteria. Lines of evidence (LoE) for bioaccumulation assessment can include bioaccumulation metrics such as in vivo bioconcentration factor (BCF) and biomagnification factor (BMF) data measured from standardized laboratory experiments, and field (monitoring) data such as BMFs, bioaccumulation factors (BAFs), and trophic magnification factors (TMFs). In silico predictions from mass-balance models and quantitative structure-activity relationships (QSARs) and a combination of in vitro biotransformation rates and in vitro-in vivo extrapolation (IVIVE) models can also be used. The myriad bioaccumulation metrics and categorization criteria and underlying uncertainty in measured or modeled data can make decision-making challenging. A weight of evidence (WoE) approach is recommended to address uncertainty. The Bioaccumulation Assessment Tool (BAT) guides a user through the process of collecting and generating various LoE required for assessing the bioaccumulation of neutral and ionizable organic chemicals in aquatic (water-respiring) and air-breathing organisms. The BAT includes data evaluation templates (DETs) to critically evaluate the reliability of the LoE used in the assessment. The DETs were developed from standardized testing guidance. The approach used in the BAT is consistent with OECD and SETAC WoE principles and facilitates the implementation of chemical policy objectives in chemical assessment and management. The recommended methods are also iterative and tiered, providing pragmatic methods to reduce unnecessary animal testing. General concepts of the BAT are presented and case study applications of the tool for hexachlorobenzene (HCB) and β-hexachlorocyclohexane (β-HCH) are demonstrated. The BAT provides a consistent and transparent WoE framework to address uncertainty in bioaccumulation assessment and is envisaged to evolve with scientific and regulatory developments. Integr Environ Assess Manag 2023;19:1235-1253. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
Topics: Animals; Bioaccumulation; Reproducibility of Results; Ecotoxicology; Uncertainty; Hexachlorobenzene; Water Pollutants, Chemical
PubMed: 35049141
DOI: 10.1002/ieam.4583 -
The Science of the Total Environment Sep 2023Research on the environmental biodegradation or microbial biodegradation of polymers has substantially increased recently due to growing demand for biodegradable... (Review)
Review
Research on the environmental biodegradation or microbial biodegradation of polymers has substantially increased recently due to growing demand for biodegradable polymers for certain applications. Environmental biodegradation of a polymer depends on the intrinsic biodegradability of the polymer and the characteristics of the receiving environment. The intrinsic biodegradability of a polymer is determined by the chemical structure and resulting physical properties (e.g., glass transition temperature, melting temperature, modulus of elasticity, crystallinity, and crystal structure) of the polymer. Quantitative structure-activity relationships (QSARs) on biodegradability have been well-established for discrete (non-polymeric) organic chemicals, but not for polymers due to the absence of adequate biodegradability data based on consistent and standardized biodegradation tests with appropriate characterization and reporting of the polymers tested. This review summarizes empirical structure-activity relationships (SARs) for biodegradability of polymers in laboratory studies involving various environmental matrices. In general, polyolefins with carbon-carbon chain are not biodegradable, while polymers containing labile bonds such as ester, ether, amide, or glycosidic bonds in their polymer chain may be favorable for biodegradation. Under a univariate scenario, polymers with higher molecular weight, higher crosslinking, lower water solubility, higher degree of substitution (i.e., higher average number of substituted functional groups per monomer unit), and higher crystallinity may result in reduced biodegradability. This review paper also highlights some of the challenges that hamper QSAR development for polymer biodegradability, stresses the need for better characterization of polymer structures used in biodegradation studies, and emphasizes the necessity for consistent testing conditions for the ease of cross-comparison and quantitative modeling analysis during future QSAR development.
Topics: Polymers; Quantitative Structure-Activity Relationship; Organic Chemicals; Carbon; Biodegradation, Environmental
PubMed: 37211122
DOI: 10.1016/j.scitotenv.2023.164338 -
Annual Review of Food Science and... Jun 2024This review discusses fundamental concepts of fat crystallization and how various processing conditions such as crystallization temperature, cooling rate, and shear or... (Review)
Review
This review discusses fundamental concepts of fat crystallization and how various processing conditions such as crystallization temperature, cooling rate, and shear or agitation affect this process. Traditional methods used to process fats, such as the use of scraped surface heat exchangers, fractionation, and interesterification, are described. Parameters that affect fat crystallization in these systems, such as shear, crystallization temperature, type of fat, and type of process, are discussed. In addition, the use of minor components to induce or delay fat crystallization based on their chemical composition is presented. The use of novel technologies, such as high-intensity ultrasound, oleogelation, and high-pressure crystallization is also reviewed. In these cases, acoustic and high-pressure process parameters, the various types of oleogels, and the use of oleogelators of differing chemical compositions are discussed. The combination of all these techniques and future trends is also presented.
Topics: Crystallization; Food Handling; Food Industry; Lipids; Pressure; Organic Chemicals
PubMed: 38166315
DOI: 10.1146/annurev-food-072023-034403 -
Advanced Materials (Deerfield Beach,... Apr 2024Recently, many organic optoelectronic materials (OOMs), especially those used in organic light-emitting diodes (OLEDs), organic solar cells (OSCs), and organic... (Review)
Review
Recently, many organic optoelectronic materials (OOMs), especially those used in organic light-emitting diodes (OLEDs), organic solar cells (OSCs), and organic field-effect transistors (OFETs), are explored for biomedical applications including imaging and photoexcited therapies. In this review, recently developed OOMs for fluorescence imaging, photoacoustic imaging, photothermal therapy, and photodynamic therapy, are summarized. Relationships between their molecular structures, nanoaggregation structures, photophysical mechanisms, and properties for various biomedical applications are discussed. Mainly four kinds of OOMs are covered: thermally activated delayed fluorescence materials in OLEDs, conjugated small molecules and polymers in OSCs, and charge-transfer complexes in OFETs. Based on the OOMs unique optical properties, including excitation light wavelength and exciton dynamics, they are respectively exploited for suitable biomedical applications. This review is intended to serve as a bridge between researchers in the area of organic optoelectronic devices and those in the area of biomedical applications. Moreover, it provides guidance for selecting or modifying OOMs for high-performance biomedical uses. Current challenges and future perspectives of OOMs are also discussed with the hope of inspiring further development of OOMs for efficient biomedical applications.
Topics: Humans; Phototherapy; Optical Imaging; Animals; Organic Chemicals; Solar Energy; Polymers; Electronics
PubMed: 37595570
DOI: 10.1002/adma.202306492 -
Environmental Science and Pollution... Aug 2023After the departure of industrial facilities, reuse of the land in developed cities in China is problematic, due to the land contamination issues. The rapid remediation...
After the departure of industrial facilities, reuse of the land in developed cities in China is problematic, due to the land contamination issues. The rapid remediation of sites with complex contamination is crucial and urgently needed. Herein, the case of on-site remediation of arsenic (As) in soil, as well as benzo(a)pyrene, total petroleum hydrocarbons, and As in groundwater was reported. For contaminated soil, the oxidant and deactivator (consisting of 20% sodium persulfate, 40% ferrous sulfate (FeSO), and 40% portland cement) were applied to oxidize and immobilize As. As a result, the total amount and lixivium concentration of As were constrained under 20 mg/kg and 0.01 mg/L, respectively. Meanwhile, for contaminated groundwater, As and organic contaminants were treated by FeSO/ozone and FeSO/hydrogen peroxide with mass ratios of 1:5 and 1:8, respectively. The continuous monitoring of contaminants in 22 monitoring wells shown that all contaminants in groundwater were treated to meet the standards. In addition, the risk of secondary pollution and operation cost was effectively reduced by proper disposal and resourceful utilization. The findings indicated that the method of oxidation and precipitation/stabilization is technically, environmentally, and economically feasible for the remediation of contaminated sites with similar complex pollutants.
Topics: Arsenic; Soil; Environmental Restoration and Remediation; Hydrocarbons; Groundwater; Soil Pollutants; Water Pollutants, Chemical
PubMed: 37432574
DOI: 10.1007/s11356-023-28604-8 -
Environmental Pollution (Barking, Essex... Sep 2023Owing to the potential influence of light-absorbing organic carbon (OC), also termed "brown carbon" (BrC), on the planetary radiation budget, many studies have focused...
Owing to the potential influence of light-absorbing organic carbon (OC), also termed "brown carbon" (BrC), on the planetary radiation budget, many studies have focused on its absorption in single-sized ranges of particulate matter (PM). However, the size distribution and organic tracer-based source apportionment of BrC absorption have not been extensively investigated. In this study, size-resolved PM samples were collected using multi-stage impactors from eastern Nanjing during each season in 2017. The light absorption of methanol-extractable OC at 365 nm (Abs, Mm) was determined using spectrophotometry, and a series of organic molecular markers (OMMs) was measured using a gas chromatography-mass spectrometer. Fine PM with an aerodynamic diameter <2.1 μm (PM) dominated Abs (79.8 ± 10.4%) of the total size ranges with maxima and minima in winter and summer, respectively. The distributions of Abs shifted to larger PM sizes from winter to spring and summer due to lower primary emissions and increased BrC chromophores in dust. Except for low-volatility (p* < 10 atm) polycyclic aromatic hydrocarbons (PAHs), the non-polar OMMs, including n-alkanes, PAHs, oxygenated PAHs, and steranes, showed a bimodal distribution pattern. Secondary products of biogenic precursors and biomass burning tracers presented a unimodal distribution peaking at 0.4-0.7 μm, while sugar alcohols and saccharides were enriched in coarse PM. Their seasonal variations in average concentrations reflected intense photochemical reactions in summer, more biomass burning emissions in winter, and stronger microbial activity in spring and summer. Positive matrix factorization was used for the source apportionment of Abs in fine and coarse PM samples. Biomass burning contributed an average of 53.9% to the Abs of PM extracts. The Abs of coarse PM extracts was associated with various dust-related sources where the aging processes of aerosol organics could occur.
Topics: Air Pollutants; Seasons; Carbon; Environmental Monitoring; Particulate Matter; China; Dust; Organic Chemicals; Aerosols; Polycyclic Aromatic Hydrocarbons
PubMed: 37302787
DOI: 10.1016/j.envpol.2023.122006 -
Environmental Pollution (Barking, Essex... Nov 2023Emissions from biomass burning (BB) vastly contribute to the atmospheric trace gases and particles, which affect air quality and human health. After emission, the...
Emissions from biomass burning (BB) vastly contribute to the atmospheric trace gases and particles, which affect air quality and human health. After emission, the chemical evolution changes the mass and composition of organic aerosol (OA) in the diluted and aged plume. In this study, we used a quasi-real atmospheric smog chamber system to conduct aging experiments and investigated the multiphase oxidation of primary organic aerosol (POA) and the formation of secondary organic aerosols (SOA) in residential biomass burning plumes. We found that the emissions in the gas and particle phases were interlinked during the plume evolution. During photochemical aging, more oxidized OA was produced, and SOA formation increased by a factor of 2 due to functionalization reactions of gaseous precursors such as furans, phenols, and carbonyls. On the other hand, dark aging resulted in a lower OA mass enhancement by a factor of 1.2, with weaker oxidation from gaseous reactions. Dark aging experiments resulted in the generation of substantial quantities of nitrogen-containing organic compounds in both gas and particulate phases, while photochemical aging led to a notable increase in the concentration of gaseous carboxylic acids. Our observations show that the properties of SOA are influenced by exposure to sunlight radiation and oxidants such as OH or NO radicals. These results reflect the aging process of BB plumes in real-world atmospheric conditions and highlight the importance of considering various aging mechanisms.
Topics: Humans; Aged; Air Pollutants; Biomass; Organic Chemicals; Aging; Aerosols; Gases
PubMed: 37757938
DOI: 10.1016/j.envpol.2023.122615 -
Environmental Research Mar 2024The current methods of treating organic waste suffer from limited resource usage and low product value. Research and development of value-added products emerges as an... (Review)
Review
The current methods of treating organic waste suffer from limited resource usage and low product value. Research and development of value-added products emerges as an unavoidable trend for future growth. Electro-fermentation (EF) is a technique employed to stimulate cell proliferation, expedite microbial metabolism, and enhance the production of value-added products by administering minute voltages or currents in the fermentation system. This method represents a novel research direction lying at the crossroads of electrochemistry and biology. This article documents the current progress of EF for a range of value-added products, including gaseous fuels, organic acids, and other organics. It also presents novel value-added products, such as 1,3-propanediol, 3-hydroxypropionic acid, succinic acid, acrylic acid, and lysine. The latest research trends suggest a focus on EF for cogeneration of value-added products, studying microbial community structure and electroactive bacteria, exploring electron transfer mechanisms in EF systems, developing effective methods for nutrient recovery of nitrogen and phosphorus, optimizing EF conditions, and utilizing biosensors and artificial neural networks in this area. In this paper, an analysis is conducted on the challenges that currently exist regarding the selection of conductive materials, optimization of electrode materials, and development of bioelectrochemical system (BES) coupling processes in EF systems. The aim is to provide a reference for the development of more efficient, advanced, and value-added EF technologies. Overall, this paper aims to provide references and ideas for the development of more efficient and advanced EF technology.
Topics: Fermentation; Bioreactors; Succinic Acid; Organic Chemicals; Technology
PubMed: 37866529
DOI: 10.1016/j.envres.2023.117422 -
Chemosphere Aug 2023Fluorescence spectroscopy has numerous applications to characterize natural and human-influenced water bodies regarding dissolved organic matter (DOM) and contamination....
Fluorescence spectroscopy has numerous applications to characterize natural and human-influenced water bodies regarding dissolved organic matter (DOM) and contamination. Analyzing samples in a timely manner is crucial to gaining valid and reproducible excitation-emission matrices (EEM) but often difficult, specifically in transnational projects with long transport distances. In this study, eight samples of different water sources (tap water, differently polluted rivers, and wastewater treatment plant (WWTP) effluents) were stored under standardized conditions for 59 days and analyzed regularly. With this data set, the sample and fluorescence spectra stability was evaluated. Established analysis methods such as peak picking and fluorescence metrics were compared over time and benchmarked against dissolved organic carbon (DOC) and a maximal change of 10% in terms of their variability. Additional high-performance liquid chromatography (HPLC) data to identify single organic compounds provides insights into these DOM alterations and allows for conclusions about the underlying biological processes. Our results corroborate in a systematic way that the higher the organic or microbial load, the faster the sample must be processed. For all water sources, considerable changes were found between days zero and one, indicating a potential systematic bias between in-situ and laboratory measurements. The absolute signals of individual peaks vary substantially after only a few days. In contrast, relative metrics are robust for a much longer time. For specific metrics, when filtered and stored under cool and dark conditions, tap water may be stored for up to 59 days, non-polluted river water for up to 31-59 days, and WWTP effluents for up to 14-59 days. The storability thus depends both on the specific water source and the analytical plan. By systematizing our understanding of how the specific water source and DOM concentration determine the stability of samples during storage, these conclusions facilitate efforts to establish a standardized protocol.
Topics: Humans; Water; Rivers; Organic Chemicals; Dissolved Organic Matter; Spectrometry, Fluorescence; Humic Substances
PubMed: 37164201
DOI: 10.1016/j.chemosphere.2023.138853 -
Ying Yong Sheng Tai Xue Bao = the... Sep 2023We investigated the effects of maize straw and its biochar application on soil organic carbon chemical composition, the abundance of carbon degradation genes (I) and the...
We investigated the effects of maize straw and its biochar application on soil organic carbon chemical composition, the abundance of carbon degradation genes (I) and the composition of I gene community in a Moso bamboo forest, to provide the theoretical and scientific basis for enhancing carbon sequestration. We conducted a one-year field experiment in a subtropical Moso bamboo forest with three treatments: control (0 t C·hm), maize straw (5 t C·hm), and maize straw biochar (5 t C·hm). Soil samples were collected at the 3 and 12 months after the treatment. Soil organic carbon chemical composition, the abundance and community composition of I gene were determined by solid-state C NMR, real-time fluorescence quantitative PCR, and high-throughput sequencing, respectively. The results showed that compared with the control, maize straw treatment significantly increased the content of O-alkyl C and decreased aromatic C content, while maize straw biochar treatment showed an opposite effect. Maize straw treatment significantly increased the abundance of I gene and the relative abundance of , and However, maize straw biochar treatment reduced the abundance of this gene. The relative abundance of dominant I in soils was positively correlated with the content of O-alkyl C and negatively correlated with the content of aromatic C. Results of redundancy analysis showed that maize straw treatment had a significant effect on the microbial community composition of I gene by changing soil O-alkyl C content, while maize straw biochar affected the microbial community composition of I gene by changing soil pH, organic carbon, and aromatic C content. Maize straw biochar treatment was more effective in increasing soil organic carbon stability and reducing microbial activity associated with carbon degradation in the subtropical Moso bamboo forest ecosystem compared with maize straw treatment. Therefore, the application of biochar has positive significance for maintaining soil carbon storage in subtropical forest ecosystems.
Topics: Carbon; Zea mays; Soil; Charcoal; Poaceae; Forests; Organic Chemicals; Microbiota
PubMed: 37899103
DOI: 10.13287/j.1001-9332.202309.018