The relationships and interactions between extracellular polymeric substances (EPS) and microplastics (MPs) in coral reef ecosystems were symmetrically investigated. The current study aims to investigate the responses of scleractinian coral (Goniopora columna) to exposure of model MPs, exemplified by polyethylene (PE), in the size range of 40–48 μm as affected by MPs concentration of MP in the range between 0 and 300 mg L⁻¹ for 14 days. The structure of EPS-associated microbial community was studied using a series of techniques including high-throughput sequencing of 16 S rRNA, transmission electron microscopy (TEM), hydrodynamic diameter, surface charge (via zeta potential), X-ray diffraction (XRD), attenuated total reflectance‒Fourier transform infrared (ATR‒FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and fluorescence excitation–emission matrix (FEEM) spectroscopy. Microbial interactions between PE-MPs and coral caused aggregation and formation of EPS matrix, which resulted in increase and decrease in the relative abundance of Donghicola (Proteobacteria phylum) and Marivita (Proteobacteria phylum) in PE-MP-associated EPS, respectively. Particle size, electrostatic interactions, and complexation with the functional groups of the EPS-based matrix affected the humification index. FEEM spectroscopy analyses suggested the presence of humic- and fulvic-like fluorophores in EPS and dissolved organic matter (DOM) in PE-MP-derived DOM. The findings provided insights into the potential environmental implications of coral-based EPS and co-existing microbial assemblages due to EPS-PE-MP-microbiome interactions throughout the dynamic PE-MP exposure process.

Current synthesis routes of bismuth oxide nanosheets (BiONS) are relatively complicated, requiring the use of halogens or metalloids. Herein, a facile method to synthesize BiONS without the addition of halogens or other metalloids was developed. The synthesized BiONS were identified to have flake-shaped structures (300–1000 nm in width) with the thickness of 6–10 nm, which were predominantly made of β-Bi₂O₃. Such BiONS were applied to modify the surface of screen-printed carbon electrodes (BiONS-SPCEs) for the development of a robust palladium (Pd²⁺) sensor. After optimizing the electrochemical parameters of the sensor, it was found that the linear sensor response range and limit of detection for Pd²⁺ were 40–400 and 1.4 ppb, respectively. The electrocatalytic activity of the Pd²⁺-sensor was validated in the competing environment of other metal and metalloid ions. Real samples collected during a Pd recovery process from pharmaceutical wastewater were used to verify the application of BiONS-SPCEs in control of palladium recovery process. The quantitative results of post recovery palladium concentrations obtained using BiONS-SPCEs in treated pharmaceutical wastewater samples were in good agreement with those obtained by inductively coupled plasma-optical emission spectrometry (ICP-OES). Thus, such Pd²⁺-sensor provided the possibility of on-site process control of complex industrial samples for obtaining near-instant information that would lead to better management of resources used in the process, and same time assure environmental standards for both recovered products and processed discharge.

With the dramatic increase in anthropogenic threats to the Pearl River Estuary (PRE), the population size of the Indo-Pacific humpback dolphins (Sousa chinensis) has significantly decreased over the past decade. To understand the impact and potential risks of intense human activities on these dolphins, factors related to the mortality of humpback dolphins in the PRE were investigated by a detailed examination of 343 dolphin specimens stranded during 2003–2017. There was a significant (p < 0.01) increasing trend for humpback dolphin stranding, reflecting the accelerating rate of the population decline. A large proportion of strandings (35.88%) were neonates. A low recruitment rate implies slow population growth, and hence, limited capacity to resist anthropogenic stress. The most commonly diagnosed causes of death were vessel collision and net entanglement. The concentrations of trace metals, polychlorinated biphenyl (PCB) congeners, dichlorodiphenyltrichloroethane, polycyclic aromatic hydrocarbons, and most of per- and polyfluoroalkyl substances (PFASs) in the dolphin samples were greater than those previously reported in cetaceans globally. Furthermore, Cu, PCB77, PCB169, PCB81, PCB37, and PFASs (excluding PFBA, PFPeA, PFHxA, PFHxDA, and PFODA) were the major pollutants accumulated in neonates. 67% of PCB, 78% of Cu, and 100% of perfluorooctane sulfonate concentrations in the neonates exceeded the threshold for toxicological effects in marine mammals, suggesting that these compounds could be important factors contributing to the low survival rate of calves in this area. This study revealed that vessel transportation, fishing activities, and pollutant bioaccumulation are the three major causes of humpback dolphin mortality in the PRE. These results highlight the need for more efforts to restrict anthropogenic activities, especially vessel traffic, the catching of these marine animals and fishing, and pollutant discharge, in order to prevent vulnerable species from continuous population decline and further extinction.

Recently, increasing attention has been paid to antibiotic resistance genes (ARGs) in urban stormwater runoff. However, there were little data on the diversity and distribution of ARGs associated with road sediments transported in runoff. The investigation of ARGs diversity showed that sulfonamide resistance genes (sul2 and sul3) occupied 61.7%–82.3% of total ARGs in runoff. The analysis of ARGs distribution in particulate matter (PM) implied that both tetQ and trbC existed mainly in PM with size of 150–300 μm, but other ARGs and mobile genetic elements (MGEs) were dominant in PM with size <75 μm. The discussion of potential hosts indicated that target genes (ermF, blaOXA1/blaOXA30, ermC, qnrA, sul2, tnpA-01, intI2, tetW, intI1, sul3, trbC) had the strongest subordinate relationship with Proteobacteria at phylum level and Enterobacter at genus level. The effect evaluation of ARGs distribution suggested that 13 kinds of ARGs were positively correlated with Pr/PS and Zeta potential, resulting in the more ARGs in PM with smaller size (<75 μm).

As a widely used pure elemental carbon in colloidal particles, carbon black was listed as a group 2B carcinogen by IARC in 2010. The most available mechanism information about carbon black and carcinogenesis are from in vivo or in vitro studies. However, few studies concerned the nanoparticle's real-ambient exposure causing systemic change and further affecting the target organ. Herein, we used an ex vivo biosensor assay to investigate the transcriptome change of primary bronchial epithelial cells after treatment with the plasma from workers with long-term occupational carbon black exposure history. Based on ex vivo biosensor assay and transcriptome sequencing, we found the effect of internal systemic environment on epithelial cells after carbon black exposure was an inflammatory response, which mainly activates cell cycle-related pathways. After exposure to carbon black, the internal systemic environment could activate cancer-related pathways like epithelial-mesenchymal transition, hypoxia, TNF-α signaling via NF-κB. The hub genes in the carbon black group (CDC20 and PLK1) and their correlation with the systemic environment were uncovered by constructing the protein-protein interaction network. Inflammatory cytokines, especially CRP, were strongly correlated with the expression of CDC20 and PLK1. Besides, we also find a strong correlation between CDC20 and cytokinesis-block micronucleus endpoints in peripheral blood (rho = 0.591, P < 0.001). Our results show that long-term carbon black exposure might activate cell cycle-related pathways through circulating inflammation and increase the risk of cancer, while the oxidative stress caused by diesel exhaust particles are mainly related to PAHs exposure. After exposure to carbon black, the systemic environment could activate cancer-related pathways like diesel exhaust particles, increasing the risk of lung cancer. These attempts might provide a further understanding of the indirect effect of chronic occupational inhaled carbon black exposure on pulmonary carcinogenesis.

Halogenated organic compounds are persistent pollutants, whose persistent contamination and rapid spread seriously threaten human health and the safety of ecosystems. It is difficult to remove them completely by traditional physicochemical techniques. In-situ remediation utilizing bioelectrochemical technology represents a promising strategy for degradation of halogenated organic compounds, which can be achieved through potential modulation. In this review, we summarize the reactor configuration of microbial electrochemical dehalogenation systems and relevant organohalide-respiring bacteria. We also highlight the mechanisms of electrode potential regulation of microbial dehalogenation and the role of extracellular electron transfer in dehalogenation process, and further discuss the application of bioelectrochemical technology in bioremediation of halogenated organic compounds. Therefore, this review summarizes the status of research on microbial electrochemical dehalogenation systems from macroscopic to microscopic levels, providing theoretical support for the development of rapid and efficient in situ bioremediation technologies for halogenated organic compounds contaminated sites, as well as insights for the removal of refractory fluorides.

This review summarizes the most relevant information on PBDEs’ occurrence and their impacts in cetaceans at global scale, with special attention on the species with the highest reported levels and therefore the most potentially impacted by the current and continuous release of these substances. This review also emphasizes the anthropogenic and environmental factors that could increase concentrations and associated risks for these species in the next future. High PBDE concentrations above the toxicity threshold and stationary trends have been related to continuous import of PBDE-containing products in cetaceans of Brazil and Australia, where PBDEs have never been produced. Non-decreasing levels documented in cetaceans from the Northwest Pacific Ocean might be linked to the increased e-waste import and ongoing production and use of deca-BDE that is still allowed in China. Moreover, high levels of PBDEs in some endangered species such as beluga whales (Delphinapterus leucas) in St. Lawrence Estuary and Southern Resident killer whales (Orcinus Orca) are influenced by the discharge of contaminated waters deriving from wastewater treatment plants. Climate change related processes such as enhanced long-range transport, re-emissions from secondary sources and shifts in migration habits could lead to greater exposure and accumulation of PBDEs in cetaceans, above all in those species living in the Arctic. In addition, increased rainfall could carry greater amount of contaminants to the marine environment, thereby, enhancing the exposure and accumulation especially for coastal species. Synergic effects of all these factors and ongoing emissions of PBDEs, expected to continue at least until 2050, could increase the degree of exposure and menace for cetacean populations. In this regard, it is necessary to improve current regulations on PBDEs and broader the knowledge about their toxicological effects, in order to assess health risks and support regulatory protection for cetacean species.

Urban green spaces (UGSs) are often positively associated with the health of urban residents. However, UGSs may also have adverse health effects by releasing biogenic volatile organic compounds (BVOCs) and increasing the ambient concentrations of ozone (O₃) and secondary organic aerosols in urban areas. BVOC emissions from UGSs might be underestimated because of the lack of consideration of the UGS land-use type in urban areas. As such, in this study, we used a newly released satellite dataset, Sentinel-2, with a resolution of 10 m, to derive the classification distribution of UGSs and predict the UGS emissions of BVOCs in Beijing in 2019. The results showed that the annual emissions of BVOCs from UGSs were approximately 2.9 Gg C (95% confidence interval (CI): 2.4–3.3) in the six core districts, accounting for approximately 39% of the total UGS emissions in Beijing. Compared with the results based on Sentinel-2, the BVOC emissions might be underestimated by approximately 37% (95% CI: 11–63) using the commonly used satellite dataset. UGSs produced the highest BVOC emissions in summer (from June to August), accounting for 75.2% of the annual emissions. UGSs contributed the most to the O₃ formation potential in summer, accounting for 41.5% of the total. We could attribute a considerable amount of the O₃ concentration (27.0 μg m⁻³, 95% CI: 21.4–32.6) to the UGS BVOCs produced in the core districts of Beijing in July. The new BVOC emissions dataset based on Sentinel-2 vegetation information facilitates modeling studies on the formation of surface O₃ in urban areas and assessments of the impact of UGSs on public health.

Novel magnetic microcomposites consisting of graphene oxide and iron oxide was synthesized to immobilize metabolically versatile Paracoccus sp. MKU1 and Leucobacter sp. AA7 and tested for the simultaneous adsorption and enhanced biological detoxification of hexavalent chromium (Cr(VI)) from tannery wastewater. This study reports highest chromium adsorption of 272.6 mg/g and 179.3 mg/g with complete reduction of Cr(VI) to Cr(III) by the microcomposites of AA7 and MKU1 from wastewater in a bioreactor (10 L) at large-scale for first time in ex situ. Furthermore, both the microcomposites displayed an enhanced detoxification of tannery wastewater by reducing various physicochemical conditions such as ammonia, nitrate, TDS, fluoride, CaCO₃, Ca, Mg, NO₃ and SO₂ under the permissible limits. Use of electromagnetic device for magnetic microcomposites recovery from bioreactor yielded a maximum of 88% and 80.6% recovery for AA7 and MKU1, respectively. The rate of chromium recuperation achieved following desorption from the microcomposites of AA7 and MKU1 was 90.71% and 93.97%, respectively. Thus, the multifarious benefits including adsorption, metabolic detoxification, recovery, and recuperation by single functional microcomposites seems to be an intriguing and profitable approach for practicing in real-time operations to effectively remove heavy metals from the contaminated wastewater for environmental protection.

Contamination of aquatic systems with pharmaceuticals, personal care products, steroid hormones, and agrochemicals has been an immense problem for the earth's ecosystem and health impacts. The environmental issues of well-known persistence pollutants, their metabolites, and other micro-pollutants in diverse aquatic systems around the world were collated and exposed in this review assessment. Waste Water Treatment Plant (WWTP) influents and effluents, as well as industrial, hospital, and residential effluents, include detectable concentrations of known and undiscovered persistence pollutants and metabolites. These components have been found in surface water, groundwater, drinking water, and natural water reservoirs receiving treated and untreated effluents. Several studies have found that these persistence pollutants, and also similar recalcitrant pollutants, are hazardous to a variety of non-targeted creatures in the environment. In human and animals, they can also have severe and persistent harmful consequences. Because these pollutants are harmful to aquatic organisms, microbial degradation of these persistence pollutants had the least efficiency. Fortunately, only a few wild and Genetically Modified (GMOs) microbial species have the ability to degrade these PPCPs contaminants. Hence, researchers have been studying the degradation competence of microbial communities in persistence pollutants of Pharmaceutical and Personal Care Products (PPCPs) and respective metabolites for decades, as well as possible degradation processes in various aquatic systems. As a result, this review provides comprehensive information about environmental issues and the degradation of PPCPs and their metabolites, as well as other micro-pollutants, in aquatic systems.