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Environmental Science. Processes &... Aug 2023Oxidized compounds in the atmosphere can occur as emitted primary compounds or as secondary products when volatile emitted precursors react with various oxidants. Due to... (Review)
Review
Oxidized compounds in the atmosphere can occur as emitted primary compounds or as secondary products when volatile emitted precursors react with various oxidants. Due to the presence of polar functional groups, their vapor pressures decrease, and they condense onto small particles. Thereby, they have an effect on climate change by the formation of clouds and scattering solar radiation. The particles and oxidized compounds themselves can cause serious health problems when inhaled. Therefore, it is of utmost importance to study oxidized compounds in the atmosphere. Much ongoing research is focused on the discovery of new oxidized substances and on the evaluation of their sources and factors influencing their formation. Monitoring biogenic and anthropogenic primary oxidized compounds or secondary oxidized products in chamber experiments or field campaigns is common. New discoveries have been reported, including various oxidized compounds and a new group of compounds called highly oxidized organic molecules (HOMs). Analytics of HOMs are mainly focused on chromatography and high-resolution mass spectrometry employing chemical ionization for identifying and quantifying compounds at low concentrations. Oxidized compounds can also be monitored by spectrophotometric methods in which the determinations of total amounts are based on functional groups. This review highlights recent findings on oxidized organic compounds in the atmosphere and analytical methodologies used for their detection and quantification. The discussion includes gas and liquid chromatographic methods, sampling, extraction, concentration, and derivatization procedures involved, as well as mass spectrometric and spectrophotometric methods.
Topics: Organic Chemicals; Mass Spectrometry; Atmosphere; Aerosols; Volatile Organic Compounds
PubMed: 37491999
DOI: 10.1039/d3em00163f -
Journal of Hazardous Materials Sep 2023Volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) are ubiquitous in indoor environment. They can emit from source into air, and subsequently...
Volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) are ubiquitous in indoor environment. They can emit from source into air, and subsequently penetrate human skin into blood through dermal uptake, causing adverse health effects. This study develops a two-layer analytical model to characterize the VOC/SVOC dermal uptake process, which is then extended to predict VOC emissions from two-layer building materials or furniture. Based on the model, the key transport parameters of chemicals in every skin or material layer are determined via a hybrid optimization method using data from experiments and literature. The measured key parameters of SVOCs for dermal uptake are more accurate than those from previous studies using empirical correlations. Moreover, the association between the absorption amount of studied chemicals into blood and age is preliminarily investigated. Further exposure analysis reveals that the contribution of dermal uptake to the total exposure can be comparable with that of inhalation for the examined SVOCs. This study makes the first attempt to accurately determine the key parameters of chemicals in skin, which is demonstrated to be critical for health risk assessment.
Topics: Humans; Volatile Organic Compounds; Air Pollution, Indoor; Air Pollutants; Skin; Construction Materials
PubMed: 37379590
DOI: 10.1016/j.jhazmat.2023.131917 -
Environmental Science & Technology Sep 2023Recent studies have shown that instantaneous gas-particle equilibrium partitioning assumptions fail to predict SOA formation, even at high relative humidity (∼85%),...
Recent studies have shown that instantaneous gas-particle equilibrium partitioning assumptions fail to predict SOA formation, even at high relative humidity (∼85%), and photochemical aging seems to be one driving factor. In this study, we probe the minimum aging time scale required to observe nonequilibrium partitioning of semivolatile organic compounds (SVOCs) between the gas and aerosol phase at ∼50% RH. Seed isoprene SOA is generated by photo-oxidation in the presence of effloresced ammonium sulfate seeds at <1 ppbv NO, aged photochemically or in the dark for 0.3-6 h, and subsequently exposed to fresh isoprene SVOCs. Our results show that the equilibrium partitioning assumption is accurate for fresh isoprene SOA but breaks down after isoprene SOA has been aged for as short as 20 min even in the dark. Modeling results show that a semisolid SOA phase state is necessary to reproduce the observed particle size distribution evolution. The observed nonequilibrium partitioning behavior and inferred semisolid phase state are corroborated by offline mass spectrometric analysis on the bulk aerosol particles showing the formation of organosulfates and oligomers. The unexpected short time scale for the phase transition within isoprene SOA has important implications for the growth of atmospheric ultrafine particles to climate-relevant sizes.
Topics: Hemiterpenes; Particulate Matter; Butadienes; Organic Chemicals; Aerosols; Air Pollutants
PubMed: 37708377
DOI: 10.1021/acs.est.3c03532 -
Environmental Research Aug 2023Beijing is a metropolis that is quickly growing, which has significant and unusual air pollution issues. In Beijing, organic matter makes up about 40%-60% of the total...
Beijing is a metropolis that is quickly growing, which has significant and unusual air pollution issues. In Beijing, organic matter makes up about 40%-60% of the total mass of fine particles, making it the most prevalent portion and highlighting its crucial role in reducing air pollution. However, a thorough chemical analysis of particulate organic matter has never been reported in Beijing. In this work, the organic components of fine particles in Beijing's urban environment were examined by the Gas Chromatography and Mass Spectrometry (GC/MS) method. In 30 p.m. (Particulate matter) 2.5, more than 101 unique chemical compounds were identified and measured. Seven samples from the 2015-2016 summer, including harvest, cold, Aromatic hydrocarbons, unsaturated fats, ferulic acid, polyaromatic, and some tracer substances (hopanes, present in environmental samples, and corticosteroids) were the main ingredients, with their total concentrations being 489, 1369, and 1366 ng*m in the summer, respectively. Due to their various primary pollution sources, such as combustion processes, fuel combustion, and culinary emissions, various organic compounds displayed ostensibly varied seasonal tendencies. Discussion of these organic chemicals' prevalence and a source reveals Beijing's seasonal air pollution patterns.
Topics: Particulate Matter; Beijing; Air Pollutants; Particle Size; Seasons; Environmental Monitoring; Organic Chemicals; China
PubMed: 37172677
DOI: 10.1016/j.envres.2023.116044 -
Ecotoxicology and Environmental Safety Apr 2024Modelling approaches to estimate the bioaccumulation of organic chemicals by earthworms are important for improving the realism in risk assessment of chemicals. However,... (Review)
Review
Modelling approaches to estimate the bioaccumulation of organic chemicals by earthworms are important for improving the realism in risk assessment of chemicals. However, the applicability of existing models is uncertain, partly due to the lack of independent datasets to test them. This study therefore conducted a comprehensive literature review on existing empirical and kinetic models that estimate the bioaccumulation of organic chemicals in earthworms and gathered two independent datasets from published literature to evaluate the predictive performance of these models. The Belfroid et al. (1995a) model is the best-performing empirical model, with 91.2% of earthworm body residue simulations within an order of magnitude of observation. However, this model is limited to the more hydrophobic pesticides and to the earthworm species Eisenia fetida or Eisenia andrei. The kinetic model proposed by Jager et al. (2003b) which out-performs that of Armitage and Gobas (2007), predicted uptake of PCB 153 in the earthworm E. andrei to within a factor of 10. However, the applicability of Jager et al.'s model to other organic compounds and other earthworm species is unknown due to the limited evaluation dataset. The model needs to be parameterised for different chemical, soil, and species types prior to use, which restricts its applicability to risk assessment on a broad scale. Both the empirical and kinetic models leave room for improvement in their ability to reliably predict bioaccumulation in earthworms. Whether they are fit for purpose in environmental risk assessment needs careful consideration on a case by case basis.
Topics: Animals; Oligochaeta; Soil Pollutants; Bioaccumulation; Pesticides; Organic Chemicals; Soil
PubMed: 38520811
DOI: 10.1016/j.ecoenv.2024.116240 -
Environmental Research Nov 2023The objectives of this study were to assess the role of soil organic matter on retaining plastic additives, Di(2-ethylhexyl) phthalate (DEHP), Bisphenol A (BPA) and...
The objectives of this study were to assess the role of soil organic matter on retaining plastic additives, Di(2-ethylhexyl) phthalate (DEHP), Bisphenol A (BPA) and Benzophenone (BP), to postulate the retention mechanisms and mobility in soil. Batch experiments were conducted for red yellow podzolic soil (OM) and soil subjected to high temperature oxidation at 600 °C for 2 h to remove total organic matter (OMR). Pristine soil, which contains organic matter abbreviated as OM (soil with organic matter) whereas total organic matter removed soil is abbreviated as OMR (organic matter removed soil). The pH edge and kinetic experiments were conducted with 20 g/L soil suspension spiked with 10 mg/L of each additive, whereas 1-20 mg/L concentration range was used in isotherm experiments and analyzed using high performance liquid chromatography. DEHP demonstrated the highest retention, 331 and 615.16 mg/kg in OM and OMR soils respectively, at pH 6.6. However, BPA and BP showed highest retentions of 132 and 128 mg/kg, respectively around pH 4.3 in pristine soil. DEHP interaction with soil OM indicated weak physical bonding whereas chemisorption to OMR soil. In the case of BPA, physisorption governed its interaction with both soil organic matter and mineral fraction. Nevertheless, BP demonstrated chemical interactions with OM and minerals. Desorption of DEHP was close to 100% however, BPA and BP were <15%. Overall, DEHP and BPA could be easily released into soil water and possibly be available for plant uptake while, BP is immobilized in soil.
Topics: Diethylhexyl Phthalate; Soil; Phthalic Acids; Soil Pollutants; Benzophenones
PubMed: 37487922
DOI: 10.1016/j.envres.2023.116725 -
Environment International Feb 2024Fish are an important pollution indicator for biomonitoring of halogenated organic compounds (HOCs) in aquatic environments, and HOCs in fish may pose health threats to... (Review)
Review
Fish are an important pollution indicator for biomonitoring of halogenated organic compounds (HOCs) in aquatic environments, and HOCs in fish may pose health threats to consumers. This study performed nontarget and comprehensive analyses of HOCs in fish from an e-waste recycling zone by gas chromatography-high-resolution mass spectrometry, and further prioritized their human exposure risks. A total of 1652 formulas of HOCs were found in the fish, of which 1222, 117, and 313 were organochlorines, organobromines, and organochlorine-bromines, respectively. The total concentrations of HOCs were 15.4-18.7 μg/g (wet weight), and organobromines were the predominant (14.1-16.8 μg/g). Of the HOCs, 41 % were elucidated with tentative structures and divided into 13 groups. The estimated total daily exposures of HOCs via dietary consumption of the fish for local adult residents were 3082-3744 ng/kg bw/day. The total exposures were dominated by several groups of HOCs with the following contribution order: polyhalogenated biphenyls and their derivatives > polyhalogenated diphenyl ethers > halo- (H-)alkanes/olefines > H-benzenes > H-dioxins > H-polycyclic aromatic hydrocarbons > H-phenols. The comprehensive characterization and prioritization results provide an overview of the species and distributions of HOCs in edible fish, and propose an inventory of crucial HOCs associated with high exposure risks.
Topics: Adult; Animals; Humans; Dioxins; Gas Chromatography-Mass Spectrometry; Halogenated Diphenyl Ethers; Hydrocarbons, Chlorinated; Organic Chemicals; Polycyclic Aromatic Hydrocarbons
PubMed: 38346376
DOI: 10.1016/j.envint.2024.108476 -
Bioorganic Chemistry Mar 2024Molecules containing C-N bonds are of paramount importance in a diverse array of organic-based materials, natural products, pharmaceutical compounds, and agricultural... (Review)
Review
Molecules containing C-N bonds are of paramount importance in a diverse array of organic-based materials, natural products, pharmaceutical compounds, and agricultural chemicals. Biocatalytic C-N bond-forming reactions represent powerful strategies for producing these valuable targets, and their significance in the field of synthetic chemistry has steadily increased over the past decade. In this review, we provide a concise overview of recent advancements in the development of C-N bond-forming enzymes, with a particular emphasis on the inherent chemistry involved in these enzymatic processes. Overall, these enzymatic systems have proven their potential in addressing long-standing challenges in traditional small-molecule catalysis.
Topics: Biocatalysis; Organic Chemicals; Catalysis
PubMed: 38244379
DOI: 10.1016/j.bioorg.2024.107108 -
Environmental Research Nov 2023Agro-based pulp and paper mills (PPMs) inevitably produce numerous refractory pollutants in their wastewater, including chlorolignin, chlorophenols, chlorocatechols,... (Review)
Review
A critical review on environmental risk and toxic hazards of refractory pollutants discharged in chlorolignin waste of pulp and paper mills and their remediation approaches for environmental safety.
Agro-based pulp and paper mills (PPMs) inevitably produce numerous refractory pollutants in their wastewater, including chlorolignin, chlorophenols, chlorocatechols, chloroguaiacol, cyanide, furan, dioxins, and other organic compounds, as well as various heavy metals, such as nickel (Ni), zinc (Zn), chromium (Cr), iron (Fe), lead (Pb), arsenic (As), etc. These pollutants pose significant threats to aquatic and terrestrial life due to their cytogenotoxicity, mutagenicity, impact on sexual organs, hormonal interference, endocrine disruption, and allergenic response. Consequently, it is crucial to reclaim pulp paper mill wastewater (PPMW) with high loads of refractory pollutants through effective and environmentally sustainable practices to minimize the presence of these chemicals and ensure environmental safety. However, there is currently no comprehensive published review providing up-to-date knowledge on the fate of refractory pollutants from PPMW in soil and aquatic environments, along with valuable insights into the associated health hazards and remediation methods. This critical review aims to shed light on the potential adverse effects of refractory pollutants from PPMW on natural ecosystems and living organisms. It explores existing effective treatment technologies for remediating these pollutants from wastewater, highlighting the advantages and disadvantages of each approach, all in pursuit of environmental safety. Special emphasis is placed on emerging technologies used to decontaminate wastewater discharged from PPMs, ensuring the preservation of the environment. Additionally, this review addresses the major challenges and proposes future research directions for the proper disposal of PPMW. It serves as a comprehensive source of knowledge on the environmental toxicity and risks associated with refractory pollutants in PPMW, making it a valuable reference for policymakers and researchers when selecting appropriate technologies for remediation. The scientific community, concerned with mitigating the widespread risks posed by refractory pollutants from PPMs, is expected to take a keen interest in this review.
Topics: Environmental Pollutants; Wastewater; Ecosystem; Lignin; Organic Chemicals; Metals, Heavy; Water Pollutants, Chemical
PubMed: 37495063
DOI: 10.1016/j.envres.2023.116728 -
The Science of the Total Environment Dec 2023Organic halamines compounds present a significant threat to the safety of drinking water due to their potential toxicity and stability. While Ultraviolet (UV)...
Organic halamines compounds present a significant threat to the safety of drinking water due to their potential toxicity and stability. While Ultraviolet (UV) disinfection is commonly used for water treatment, its specific effects on organic halamines and the underlying mechanisms remain poorly understood. In this study, we investigated eight amino acid-derived organic chlor- and bromamines as representative compounds. Our findings revealed that organic halamines have a slow hydrolysis rate (<10 M s) and can persist in water for extended periods (30-2000 min). However, their disinfection efficacy against Staphylococcus aureus and their ability to degrade micropollutants like carbamazepine were found to be limited. Interestingly, under UV irradiation, the N-X bonds in organic halamines were observed to break, leading to accelerated decomposition and the generation of abundant free radicals. These free radicals synergistically facilitated the removal of micropollutants and the inactivation of pathogenic microorganisms. It is worth noting that this transformation of organic halamines during UV disinfection resulted in a slight increase in the concentrations of nitrogenous disinfection byproducts. These findings shed light on the behavior and characteristics of organic halamines during UV disinfection processes, providing crucial insights for effectively managing drinking water quality impacted by these compounds. By understanding the implications of organic halamines, we can refine water treatment strategies and ensure the safety of drinking water supplies.
Topics: Drinking Water; Disinfection; Ultraviolet Rays; Water Supply; Water Purification; Organic Chemicals; Free Radicals; Water Pollutants, Chemical; Chlorine
PubMed: 37536590
DOI: 10.1016/j.scitotenv.2023.165994