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A magnetic covalent organic framework nanomaterial (Fe3O4@COFs) served as an adsorbent for enrichment and a new matrix for SALDI-TOF-MS analysis of PAHs and their derivatives in PM2.5. The unique properties of Fe3O4@COFs in terms of high enrichment ability and matrix-free interference made it possible for sensitive analysis of low-concentration organic small-molecule pollutants in complex environmental samples. [ABSTRACT FROM AUTHOR]

Abstract Carbon dots (CDs) have attracted much attention in a variety of fields owing to the diversified properties. However, the control of the structure and surface function of CDs are still urgent issues to be addressed for using it in specific application. Herein, the reduced state of carbon nanodots (R-CDs) has been produced through a convenient strategy by reduction of the pure carbon dots products, which was utilized as a good candidate of matrix for direct analysis of bisphenol (BP) analogs in negative-ion surface-assisted laser desorption/ionization time-of-flight mass spectrometry (SALDI-TOF MS). Due to the dominant hydroxyl groups on the surface of R-CDs, they were easier to absorb BPs through hydrogen bonding and van der Waals interactions, resulting in highly efficient detection of BPs. Meanwhile, compared with the organic matrix and raw carbon dots, the superior surface structure and properties of this R-CDs surface provide various advantages including low background noise, outstanding sensitivity and salt tolerance. This work opens a door for developing R-CDs as alternative substrate in SALDI-TOF MS for direct detection of small molecule pollutants. Graphical abstract fx1 Highlights • Reduced carbon nanodots (R-CDs) was used as a novel candidate for detection bisphenol analogs (BPs) in SALDI-TOF MS. • The R-CDs-assisted LDI MS exhibited low background noise, high sensitivity and salt tolerance in analysis of BPs. • This work provides a good alternative substrate to SALDI-TOF MS and expands the CDs’ new application scope. [ABSTRACT FROM AUTHOR]

[Display omitted] • The promoted generation strategies of 1O 2 in PS activation by modified-nZVI systems and nZVI-based coupling systems are summarized. • The influence factors on the generation and behavior of 1O 2 in nZVI/PS-based systems are reviewed. • The selectivity, wide pH adaptability and corresponding roles of 1O 2 in organic pollutants degradation are reviewed. • The challenges and prospects of 1O 2 generation in nZVI/PS-based systems are addressed. In recent years, the remediation of water contamination through non-radical pathways by singlet oxygen (1O 2) has caught scientists' increasing attention owing to the adaptability to wider pH range and superior selectivity to target pollutants. In this review, strategies of promoting the generation of 1O 2 in persulfate activation over nanoscale zero-valent iron (nZVI) and the corresponding roles of 1O 2 in degrading pollutants are summarized systematically, chiefly illustrating the mechanisms of persulfate activation to produce 1O 2. The reasons underlying improvements in the degradation of organic pollutants originate from increased generation and enhanced activity of 1O 2 in modified systems and coupling systems based on nZVI. Additionally, in order to figure out how external environment affects the generation and behavior of 1O 2 , several major influence factors are also compared and evaluated. On the whole, this paper draws a relatively clear picture of 1O 2 in the combination of persulfate and nZVI-based systems, opening novel perspective of capitalizing on the merits of 1O 2 to deal with the increasingly troublesome problem of water pollution. [ABSTRACT FROM AUTHOR]

In today's society, wastewater sludge has become solid waste, and the preparation of wastewater sludge into sludge biochar nanomaterials (SBCs) for resource utilization has become a promising method. SBCs have advantages over other biomasses, including their complex composition, wide range of raw materials, and especially the presence of various transition metals with catalytic properties. Heterogeneous Fenton processes using SBCs as catalyst carriers have shown great potential in the removal of pollutants. In this review, the synthesis methods of SBCs are reviewed and the effects of different synthesis methods on their physicochemical properties are discussed. Furthermore, the successful applications of raw SBCs, metal-modified SBCs, and Fenton sludge-SBCs in organic pollutant degradation, sediment remediation, and sludge dewatering are reviewed. The mechanisms occurring with different metals as active sites are explored, and the review shows that the degradation efficiency and stability of SBCs are very satisfactory. We also provide an outlook on the future development of SBCs. We hope that this review will help readers gain a clearer and deeper understanding of SBCs and promote the development of SBCs. [Display omitted] • Synthesis methods can affect the physicochemical properties of SBCs. • An overview of the mechanism and reusability of SBCs for pollutant degradation. • Summarized the application of SBCs in sludge dewatering. • Presented the challenges and prospects of SBCs in the Fenton-like field. [ABSTRACT FROM AUTHOR]

We reported the discovery and identification of emerging sulfur-containing polycyclic aromatic hydrocarbons, namely polycyclic aromatic sulfur heterocycles (PASHs), in PM 2.5 collected from two typical regions of China, Taiyuan and Guangzhou. Until now, there is no research on contamination status, sources and potential health risks of this unexpected group of organic contaminants in PM 2.5. High atmospheric concentrations (ng m−3) and significant time-dependent variations were determined in PM 2.5 of Taiyuan from 2017 to 2018. Coal combustion/secondary formation and traffic emission/secondary formation were apportioned as possible pollution sources for the PM 2.5 -bound PASHs in Taiyuan and Guangzhou, respectively. Dithiothreitol and cell viability assays were applied for evaluations of PASH-induced reactive oxygen species (ROS) production and cell toxicity based on the determined real exposure levels for adults. The results illustrated that PASHs in PM 2.5 possibly caused oxidative stress and inhibition of human bronchial epithelial cells in seriously polluted regions such as Taiyuan, suggesting that the pollutant-induced health concerns may need more investigations. This study provides new insights into PM 2.5 pollution, and is beneficial for the development of effective contamination control strategies and reduction of risks on public health. [Display omitted] • Detailed contamination levels of PM 2.5 -bound PASHs were firstly studied. • Different pollution sources were identified in Taiyuan and Guangzhou. • The PM 2.5 -bound PASHs possessed potential health risks for human inhalation. [ABSTRACT FROM AUTHOR]

Industrial progress has brought us an important polymer material, i.e. plastic. Because of mass production and use, and improper management and disposal, plastic pollution has become one of the most pivotal environmental issues in the world today. However, the current researches on microplastics/nanoplastics are mainly focused on individual aquatic, terrestrial and atmospheric environments, ignoring the fact that the natural environment is a whole. In this regard, the transport of microplastics/nanoplastics among the three environment compartments, including reciprocal contributions and inherent connections, and the impact of microplastics/nanoplastics on organisms living in multiple environments are research problems that we pay special attention to. Furthermore, this paper comprehensively reviews the transport and distribution of microplastics/nanoplastics in individual compartments and the toxicity of organisms, either alone or in combination with other pollutants. The properties of microplastics/nanoplastics, environment condition and the growth habit of organisms are critical to the transport, distribution and toxicity of microplastics/nanoplastics. These knowledge gaps need to be addressed urgently to improve cognition of the degree of plastic pollution and enhance our ability to deal with pollution. Meanwhile, it is hoped that the paper can provide a relatively complete theoretical knowledge system and multiple "leads" for future innovative ideas in this field. ga1 • Discuss the interface transport of microplastics/nanoplastics (MPs/NPs) among three major environment compartments. • Analyze the effects of MPs/NPs to creatures that need to span aquatic, terrestrial and atmospheric environment. • Completely review the transport pathway and toxicity of MPs/NPs in individual environments. [ABSTRACT FROM AUTHOR]

• OPFRs were detected ubiquitously in PM 2.5 from Guangzhou and Taiyuan, China. • Cl-OPFRs such as TCEP and TCPP were the predominant contaminants in PM 2.5. • PM 2.5 -bound OPFRs could induce the death of BEAS-2B cells. • PM 2.5 in Taiyuan had strong redox activities for ROS production. • Minimum health risks to both toddlers and adults by PM 2.5 -bound OPFRs were found. Organophosphate flame retardants (OPFRs) are emerging contaminants in recent years. They can be present in the atmospheric fine particle (PM 2.5), leading to potential adverse effects on humans. In this study, the concentrations and in vitro toxicities of OPFRs in PM 2.5 samples were investigated for one year at Guangzhou and Taiyuan in China. Eleven OPFRs, including chloro-, aryl-, and alkyl-substituted OPFRs, were detected at total concentrations ranging from 3.10 to 544 ng m−3. Chloro-substituted OPFRs were the dominant contaminants. Based on the statistical analysis, the same contamination sources of all OPFRs were found except for tris(butoxyethyl) phosphate (TBOEP) and triethyl phosphate (TEP), which may come from traffic emission. The results of cell viability and dithiothreitol assays indicated that OPFRs and PM 2.5 could induce the death of normal lung epithelial cells and the production of reactive oxygen species (ROS), respectively. According to the redundancy analysis, the distribution of OPFRs was significantly related to the PM 2.5 concentrations and indirectly associated with ROS production induced by PM 2.5 from Taiyuan. Exposure to PM 2.5 -bound OPFRs in Guangzhou and Taiyuan only posed minimum health risks to both toddlers and adults. These findings could provide important evidence to better clarify the contamination profiles and human health risks of OPFRs in atmospheric fine particles. [ABSTRACT FROM AUTHOR]