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The concentrations of trace elements including As, Zn, Cu, Se, Pb, Hg and Cd, were determined in the blood of nesting Kemp's ridley turtles (Lepidochelys kempii) at Rancho Nuevo sanctuary, Tamaulipas, Mexico during 2018-2020. The sequential concentrations analyzed were Zn> Se> Cu> As> Pb; while Cd and Hg concentrations were below the limits of detection (0.01 [mu]g g.sup.-1). No significant differences were observed between the concentrations of trace elements (p> 0.05) by year, except Se levels, possibly resulting from recorded seasonal differences in turtle size. No relationships among turtle size vs elements concentration were observed. In conclusion, essential and toxic trace elements concentrations in the blood of nesting Kemp's ridley turtles may be a reflex of the ecosystem in which the turtles develop, that is, with low bioavailability of elements observed in the trophic webs in the Gulf of Mexico.

We investigated the distribution patterns and evaluated the average contents of trace elements in the k[sub.7] seam of the Karaganda coal basin in Central Kazakhstan. This paper presents the results of studying the geochemistry of 34 elements in 85 samples of the k[sub.7] seam. The study employed a suite of advanced high-resolution analytical methods, including atomic emission spectrometry with inductively coupled plasma (ICP–OES) and mass spectrometry with inductively coupled plasma (ICP–MS), along with their processing and interpretation. It was determined that the concentrations of trace elements in the k[sub.7] seam are primarily associated with lithophile elements, revealing high concentrations of Li, V, Sc, Zr, Hf, and Ba. Additionally, increased concentrations of Nb, Ta, Se, Te, Ag, and Th were observed compared to the coal Clarke. Specific Nb(Ta)–Zr(Hf)–Li mineralization accompanied by a group of associated metals (Ba, V, Sc, etc.) was identified. The study revealed lateral and vertical heterogeneity of the rare elements’ distributions in coals, attributed to the formation dynamics of the coal basin. A correlation between Li and Al[sub.2] O[sub.3] with a less positive relationship with K[sub.2] O suggests the affinity of certain elements (Li, Ta, Nb, and Ba) to kaolinite. Clay layers showed increased radioactivity, with Th—13.2 ppm and U—2.6 ppm, indicating the possible presence of volcanogenic pyroclastic rocks characterized by radioactivity. Taken together, these data reveal the features of the rock composition of the source area, which is considered a mineralization source. According to geochemical data, it was found that the source area mainly consists of igneous felsic rocks, indicating that the formation occurred under conditions of a volcanic arc. This study’s novelty lies in estimating the average trace elements in the k[sub.7] seam, with elevated concentrations of certain elements that suggest promising prospects for industrial extraction from coals and coal wastes. These findings offer insights into considering coal as a potential source of raw material for rare metal production, guiding the industrial processing of key elements within coal. The potential extraction of metals from coal deposits, including from dumps, holds significance for industrial and commercial technologies, as processing critical coal elements can reduce disposal costs and mitigate their environmental impact.

Chlorinated Organic Micropollutants addresses the sources, environmental cycles, uptake, consequences and control of many of the more important chlorinated organic micropollutants, including PCBs, PCDDs, PCDFs and various chlorinated pesticides, all of which have given widespread cause for concern in relation to their environmental persistence and high toxicity, and their potential for adverse effects on humans and wildlife. Rational decision making over chlorinated organic micropollutants in the environment must be based upon sound science. This volume draws upon the expertise of some of the most distinguished workers in the field, to review current knowledge of the sources, environmental concentrations and pathways, human toxicity and ecotoxicology, and control methods for these groups of compounds. Chlorinated Organic Micropollutants gives a unique and valuable compilation of information on an extremely important group of environmental pollutants. It is fully up-to-date, and will provide a comprehensive overview of this topical subject that will be useful for years to come, to academic, student and professional alike.

Engineering a catalytic membrane capable of efficiently removing emerging organic microcontaminants under ultrahigh flux conditions is of significance for water purification. Herein, drawing inspiration from the functional attributes of lymphatic vessels involved in immunosurveillance and fluid transport with minimal energy consumption, a novel hierarchical porous catalytic membrane is engineered. This membrane, based on an innovative nitrogen‐rich conjugated microporous polymer (polytripheneamine, PTPA), is synthesized using an electrospinning coupled in situ polymerization approach. The resulting bioinspired membrane with hierarchical channels comprises a thin layer (≈1.7 µm) of crosslinked PTPA nanoparticles covering the interconnected electrospun nanofibers. This unique design creates an intrinsic microporous angstrom‐confined system capable of activating peroxymonosulfate (PMS) to generate 98.7% singlet oxygen (1O2), enabling durable and highly efficient degradation of microcontaminants. Additionally, the presence of a thin layer of mesoporous structure between PTPA nanoparticles and macroporous channels within the interwoven nanofibers enhances mass transfer efficiency and facilitates high flux rates. Notably, the prepared hierarchical porous organic catalytic membrane demonstrates enduring high‐efficiency degradation performance with a superior permeance (>95% and >2500 L m−2 h−1 bar−1) sustained over 100 h. This work introduces an innovative pathway for the design of high‐performance catalytic membranes for the removal of emerging organic microcontaminants. Inspired by the functional attributions of lymphatic vessels in immunosurveillance and fluid transport with minimal energy consumption, a novel hierarchical porous polymer catalytic membrane, based on the innovative nitrogen‐rich conjugated microporous polymers, is engineered for ultrafast, highly efficient, and long‐lasting removal of emerging organic micropollutants from water under ultrahigh flux conditions.

The factors limiting micropollutant biodegradation in the environment and how to stimulate this process have often been investigated. However, little information is available on the capacity of microbial communities to retain micropollutant biodegradation capacity in the absence of micropollutants or to reactivate micropollutant biodegradation in systems with fluctuating micropollutant concentrations. This study investigated how a period of 2 months without the addition of micropollutants and other organic carbon affected micropollutant biodegradation by a micropollutant-degrading microbial community. Stimulation of micropollutant biodegradation was performed by adding different types of dissolved organic carbon (DOC)—extracted from natural sources and acetate—increasing 10 × the micropollutant concentration, and inoculating with activated sludge. The results show that the capacity to biodegrade 3 micropollutants was permanently lost. However, the biodegradation activity of 2,4-D, antipyrine, chloridazon, and its metabolites restarted when these micropollutants were re-added to the community. Threshold concentrations similar to those obtained before the period of no substrate addition were achieved, but biodegradation rates were lower for some compounds. Through the addition of high acetate concentrations (108 mg-C/L), gabapentin biodegradation activity was regained, but 2,4-D biodegradation capacity was lost. An increase of bentazon concentration from 50 to 500 µg/L was necessary for biodegradation to be reactivated. These results provide initial insights into the longevity of micropollutant biodegradation capacity in the absence of the substance and strategies for reactivating micropollutant biodegrading communities. Graphical abstract

The Environmental Trace Gases Monitoring Instrument (EMI-II) onboard the Chinese GaoFen-5B (GF5B) and DaQi-1 (DQ1) satellites is the successor of the previous EMI onboard the Chinese GaoFen-5 (GF5) satellite, and has a higher spatial resolution and a better signal-to-noise ratio. The GF5B and DQ1 were launched in September 2021 and April 2022, respectively. As part of China’s ultraviolet-visible hyperspectral satellite instrument series, the EMI-II aims to conduct network observations of pollution gases globally in the morning and early afternoon. In this study, NO[sub.2] data were retrieved from the EMI-II payloads on the GF5B and DQ1 satellites using the Differential Optical Absorption Spectroscopy (DOAS) algorithm. The two satellites were consistently compared, and the results showed strong consistency on various spatial and temporal scales (R[sup.2] > 0.8). In four representative regions worldwide, NO[sub.2] data from the EMI-II exhibited good spatial consistency with those from the TROPOMI. The correlation coefficient (R[sup.2] ) of the total vertical column density (VCD) between the EMI-II and TROPOMI exceeded 0.85, and that of the tropospheric NO[sub.2] VCD exceeded 0.57. Compared with single-satellite observations, the dual-satellite network of the GF5B and DQ1 can effectively increase the observation frequency. On a daily scale, dual-satellite observations can reduce the impact of cloud coverage by 6–8% compared to single-satellite observations, and there are two valid observations of nearly 50% of the world’s regions. Additionally, the differences between the two satellites can reflect the NO[sub.2] diurnal variations, which demonstrates the potential for studying pollutant gas diurnal variations.

Removal of organic micropollutants from water through advanced oxidation processes (AOPs) is hampered by the excessive input of energy and/or chemicals as well as the large amounts of residuals resulting from incomplete mineralization. Herein, we report a new water purification paradigm, the direct oxidative transfer process (DOTP), which enables complete, highly efficient decontamination at very low dosage of oxidants. DOTP differs fundamentally from AOPs and adsorption in its pollutant removal behavior and mechanisms. In DOTP, the nanocatalyst can interact with persulfate to activate the pollutants by lowering their reductive potential energy, which triggers a non-decomposing oxidative transfer of pollutants from the bulk solution to the nanocatalyst surface. By leveraging the activation, stabilization, and accumulation functions of the heterogeneous catalyst, the DOTP can occur spontaneously on the nanocatalyst surface to enable complete removal of pollutants. The process is found to occur for diverse pollutants, oxidants, and nanocatalysts, including various low-cost catalysts. Significantly, DOTP requires no external energy input, has low oxidant consumption, produces no residual byproducts, and performs robustly in real environmental matrices. These favorable features render DOTP an extremely promising nanotechnology platform for water purification. Removal of organic micropollutants from water through advanced oxidation processes is hampered by the excessive input of energy and/or chemicals as well as the large amounts of residuals resulting from incomplete mineralization. Here the authors present a new alternative water purification technology to adsorption and advanced oxidation.

This study extends a previously developed competitive modeling approach for predicting the adsorption of organic micropollutants (OMPs) on powdered activated carbon (PAC) in full-scale advanced wastewater treatment. The approach incorporates adsorption analysis for organic matter fractionation, assumes pseudo-first order kinetics and differentiates between fresh and partially loaded PAC through fraction segregation. Validation through full-scale measurement campaigns reveals successful model predictions of OMP removal, underestimating, however, diclofenac removals by 15–20%. Based on model testing, the impact of excess PAC return to the biological stage enhanced OMP removal, reaching up to 15% improvement for benzotriazole, carbamazepine and metoprolol, but no evident improvement of diclofenac removal. Intermittent PAC dosing revealed rapid process response, where organic matter concentration increased within 2 h after PAC cut-off. The simulation-based study demonstrated that during rain events, the overall OMP removal efficiency in the entire wastewater treatment plant was reduced by approximately 50% due to a shift of OMP concentration and a shortened hydraulic retention time in the biological and adsorption stages. Testing of various PAC dosing strategies revealed potential PAC savings of 10–15% compared to inflow-proportional dosing by using predefined OMP removal grades or maximum allowable effluent OMP concentrations as criteria for PAC dosing.

Visible light-sensitized oxidation of micropollutants (MPs) in the presence of meso-tetrakis(4-sulfonatophenyl)porphyrin photosensitizers was studied. In order to explore the role of type I (ROS generation) or type II (singlet oxygen) photooxidation, radical scavengers were used to obtain insight into the mechanism of photodegradation. It was revealed that singlet oxygen is the main ROS taking part in TPPS[sub.4]- sensitized photooxidation of micropollutants. The interaction of MPs with [sup.1]O[sub.2] in deuterium oxide (D[sub.2]O) was investigated by measuring the phosphorescence lifetime of [sup.1]O[sub.2]. The rate constant (kq) for the total (physical and chemical) quenching of [sup.1]O[sub.2] by MPs was determined in a D[sub.2]O buffer (pD 7, 9 and 10.8). The rate constants of singlet oxygen quenching and reaction with MPs were determined, and the rate constant of excited TPPS[sub.4] quenching by MPs was also estimated.

Micropollutants in the aquatic environment pose a high risk to both environmental and human health. The photocatalytic degradation of steroid hormones in a flow-through photocatalytic membrane reactor under UV light (365 nm) at environmentally relevant concentrations (50 ng l–1 to 1 mg l–1) was examined using a polyethersulfone–titanium dioxide (PES–TiO2) membrane. The TiO2 nanoparticles (10–30 nm) were immobilized both on the surface and in the nanopores (220 nm) of the membrane. Water quality and operational parameters were evaluated to elucidate the limiting factors in the degradation of steroid hormones. Flow through the photocatalytic membrane increased contact between the micropollutants and ·OH in the pores. Notably, 80% of both oestradiol and oestrone was removed from a 200 ng l–1 feed (at 25 mW cm–2 and 300 l m–2 h–1). Progesterone and testosterone removal was lower at 44% and 33%, respectively. Increasing the oestradiol concentration to 1 mg l–1 resulted in 20% removal, whereas with a 100 ng l–1 solution, a maximum removal of 94% was achieved at 44 mW cm–2 and 60 l m–2 h–1. The effectiveness of the relatively well-known PES–TiO2 membrane for micropollutant removal has been demonstrated; this effectiveness is due to the nanoscale size of the membrane, which provides a high surface area and facilitates close contact of the radicals with the very small (0.8 nm) micropollutant at an extremely low, environmentally relevant concentration (100 ng l–1).A polyethersulfone–titanium dioxide membrane is demonstrated to be effective at micropollutant removal during the photocatalytic degradation of steroid hormones in a flow-through photocatalytic membrane reactor under UV light at environmentally relevant concentrations.