Higher Fine Particle Fraction in Sediment Increased Phosphorus Flux to Estuary in Restored Yellow River Basin.

River delta-front estuaries (DEs) are vital interfaces for fluxes between terrestrial and marine environments. However, deep uncertainty exists in estimating the sedimentary pollutant flux from terrestrial environments in DEs due, in part, to a lack of direct measurements in these dynamic and complicated regions and uncertainty in the calculation method. Due to its high sediment content, the Yellow River (YR) has a strong ability to adsorb phosphorus; therefore, it reliably reflects estuarine sedimentary processes. Here, through the comprehensive analysis of field samples, monitoring data and remote sensing images, we conclude that riverine fine particles control the deltaic estuary pollution status and that particle size is the key factor. Based on the stable relationships between phosphorus and heavy metals, with r2 values of 0.990, 0.992, and 0.639 for As, Cd, and Cr, respectively, we estimated that the P flux reached 22.68 g/m2 yr in 2017. Analysis of the YR high-silt sediment load, which has a strong phosphorus adsorption ability and constitutes a substantial fraction of global fluvial sediment transport, revealed a negative correlation between the riverine sediment load and the estuarine phosphorus flux.

First determination of extracellular paralytic shellfish poisoning toxins in the culture medium of toxigenic dinoflagellates by HILIC-HRMS.

Paralytic shellfish poisoning (PSP) toxins have received considerable attention in recent years because of their adverse effects on marine breeding industries and human health. In this study, a reliable method for the analysis of extracellular PSP toxins in the culture medium of marine toxic dinoflagellates was developed for the first time using graphitized carbon black-solid-phase extraction and hydrophilic interaction liquid chromatography-high-resolution mass spectrometry. The limit of quantification of typical PSP toxins in algal culture medium ranged from 0.072 µg/L to 0.151 µg/L under optimal conditions. Satisfactory absolute recoveries (87.5%-102.4%), precision (relative standard deviation ≤ 7.6%), and linearity (R2 ≥ 0.9998) were also achieved. In addition, the proposed method was applied to screen and determine the extracellular PSP toxins of two typical toxigenic dinoflagellates, Alexandrium minutum and Alexandrium tamarense. The total concentrations of the extracellular PSP toxins in A. minutum and A. tamarense over the whole growth period were within 2.0-735.5 and 2.0-19.2 µg/L, respectively. The concentrations of extracellular PSP toxins varied remarkably in the different growth stages of A. minutum and A. tamarense, and the contents of some extracellular PSP toxins were substantially higher than those of intracellular PSP toxins. Therefore, the extracellular PSP toxins released by toxigenic red tide algae cannot be ignored, and their environmental fate, bioavailability, and potential harm to aquatic environment need to be investigated in future studies.

Monitoring and warning of lipophilic marine algal toxins in mariculture zone based on toxin profiles of phytoplankton.

Some toxigenic dinoflagellates can produce lipophilic marine algal toxins (LMATs), which are potent threats to marine breeding industries. In this study, a new method based on the profiling analysis of six LMAT classes in phytoplankton was developed for the monitoring and warning of LMATs in mariculture zones. This method was applied to monitor and evaluate LMATs in the Jiaozhou Bay and the Changjiang estuary in China. Results demonstrated that the occurrence and spatiotemporal variations of LMATs in mariculture zones can be revealed by the toxin profiles of phytoplankton, indicating the method's effectiveness for the comprehensive monitoring of the composition and levels of various LMATs in coastal aquaculture zones. The method was further used as an alarm for potential pollution risk from LMATs in mariculture zones at an early stage. The "alert" thresholds of LMAT pollution in the mariculture zones were preliminarily proposed based on the statistical data analysis of LMATs in phytoplankton in three typical mariculture areas in China. This study is the first to conduct simultaneous monitoring and warning of multi-class LMATs based on toxin profiles of phytoplankton, thereby providing new insight into the monitoring and early warning of natural poisonous pollutants in coastal aquaculture zones around the world.

Simultaneous determination of eight neonicotinoid insecticides, fipronil and its three transformation products in sediments by continuous solvent extraction coupled with liquid chromatography-tandem mass spectrometry.

Neonicotinoids (NEOs) and fipronil (FIP) are insecticides that are widely used in modern agriculture and have received considerable attention in recent years due to their adverse effects on non-target organisms in the environment. In the present study, a new method to simultaneously detect eight common NEO insecticides and FIP and its three transformation products (FIPs) in sediments was developed using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) based on a combined pretreatment of continuous solvent extraction (CSE) and solid phase extraction (SPE). Under optimized conditions, 5.0 g of freeze-dried sediment samples were initially extracted with methanol (20 mL)-methanol (15 mL)-water (20 mL) in sequence, and then the extract was cleaned with hydrophilic-lypophilic balance SPE cartridges, and HPLC-MS/MS analysis was conducted. The established method was validated to be sensitive, linear, accurate, and precise. The limits of detection (LOD) and limits of quantification (LOQ) of target compounds were 0.012-0.055 µg/kg d.w and 0.031-0.091 µg/kg d.w, respectively. Good linearity (R2 > 0.990) was observed between 4.0 × 10-2 and 20.0 µg/kg d.w. The recovery rates of all target insecticides were between 75.5% and 98.5%, and the relative standard deviations (RSD) were all less than 15.0% at the low, medium, and high spiked levels. Finally, the optimized method was applied to analyze 12 target insecticides in the sediments obtained from Jiaozhou Bay of China and its main inflow rivers. Acetamiprid, thiamethoxam, fipronil sulfide, and fipronil sulfone were detected in the river sediment samples at the concentration from

VxMn(4-x)Mo3Ce3/Ti catalysts for selective catalytic reduction of NO by NH3.

A series of vanadium based catalysts (VxMn(4-x)Mo3Ce3/Ti) with different vanadium (x wt.%) and manganese ((4-x) wt.%) contents have been prepared by the wet impregnation method and investigated for selective catalytic reduction (SCR) of NOx by NH3 in the presence of 8 vol.% H2O and 500 ppmV SO2. The physicochemical characteristics of the catalysts were thoroughly characterized. The SCR of NOx by NH3 (NH3-SCR) activity, especially the low-temperature activity, significantly increased with increasing V2O5 content in the catalyst until the V2O5 content reached 1.5 wt.%, which corresponds well with the redox properties of the catalyst. All of the metal oxides were well dispersed and strongly interacted with each other on the catalyst surface. V mainly exists in the V5+ state in the catalysts. The strong synergistic effect between the vanadium and cerium species led to formation of more Ce3+ species, and that between the vanadium and manganese species contributed to formation of more manganese species with low valences. All of the catalysts exhibited strong acidity, while the redox properties determined the NH3-SCR activity, especially the low-temperature activity. H2O and SO2 had severe inhibiting effects on the activity of V1.5Mn2.5Mo3Ce3/Ti. However, good H2O and SO2 resistance and high NOx conversion by V1.5Mn2.5Mo3Ce3/Ti could be achieved in the presence of SO2 and almost no decline was observed in a long-term test at 275°C for 168 hr in the presence of SO2 and H2O, which can be attributed to the sulfate species formed on the catalyst surface.

Visible-Light Photocatalytic Activity of Fe and/or Ni Doped Ilmenite Derived-Titanium Dioxide Nanoparticles.

Pure TiO2 nanoparticles and ones doped with Fe and/or Ni were successfully prepared by a co-precipitation method from ilmenite. The samples were structurally characterized by XRD, XPS, FT-IR, UV-vis, SEM, EDX, AAS and BET measurement. The XRD results showed that all samples were anatase TiO2, and no characteristic peaks of dopants were observed. The crystallite sizes of all doped TiO2 nanoparticles were less than 20 nm and doping TiO2 with metal ions can suppress the crystal growth of the particles. The XRD and XPS results indicated that TiO2 was uniformly doped and its crystalline phase was not changed by doping. The specific surface area of Fe-Ni/TiO2 is bigger than that of the un-doped TiO2. The pore size and pore volume of Fe-Ni/TiO2 is smaller than that of the un-doped. UV-vis spectra of the samples showed that the absorption edge red shifted with increasing doped metal content. The photocatalytic activity was evaluated in oxidative degradation of methylene blue (MB) with H2O2 under visible light irradiation. When doped with a single type of transition metal, the photocatalytic performance of Ni-doped samples was lower than that of Fe-doped ones. For the co-doped catalysts, the catalytic efficiency of 0.5%Fe4%Ni/TiO2 was the highest, reaching 93.34% after 250 min. Metal doping enhanced the photocatalytic decomposition of methylene blue compared with that of pure TiO2 by up to 1.5 times. The synergistic effects of the two metal ions improved the photocatalytic performance. The particles exhibited pronounced activity in degradation of MB as well as efficient recyclability. The photocatalytic degradation mechanism of methylene blue was analyzed.

CuO modified vanadium-based SCR catalysts for Hg0 oxidation and NO reduction.

The catalytic performance of Hg0 oxidation over vanadium-based SCR catalysts modified by different addition amounts of CuO was investigated. All catalysts were prepared by impregnation method and characterized. The 7% Cu/VWTi exhibited high Hg0 oxidation as well as a desired NO removal efficiency at 280-360 °C. The characterization revealed the enhancement of redox properties and well-dispersed active species results in the high catalytic performance after modification. The incorporation model showed that CuO in 7% Cu/VWTi was present in the monolayer dispersion, leading to the highest performance. Moreover, the effects of O2, NO, SO2, NH3 and HCl were explored. It showed all flue gas except NH3 could promote Hg0 oxidation. Fortunately, the inhibiting effect of NH3 could be scavenged if the catalyst is installed at the downstream of the SCR reactor. In addition, the mechanism of Hg0 oxidation over Cu/VWTi was discussed.

Trifluoperazine Inhibits Mesangial Cell Proliferation by Arresting Cell Cycle-Dependent Mechanisms.

BACKGROUND It has been reported that trifluoperazine (TFP) inhibits proliferation of cancer cells, however, the effects of TFP in renal proliferation diseases are still unclear. This study examined the effects of TFP on proliferation of human renal mesangial cells and analyzed the underlying mechanisms. MATERIAL AND METHODS Cell proliferation in vivo was determined by HE staining, immunohistochemistry of proliferating cell nuclear antigen (PCNA), and Western blot analysis (Ki-67 and PCNA). Effects of different TFP concentrations and treatment duration on cell proliferation and cell cycle were analyzed using the MTT assay and flow cytometry. Expression of G0/G1 phase cell cycle-related proteins and TFP-induced MAPK and PI3K/AKT signaling pathways was estimated with Western blot analysis. RESULTS Our findings suggest that TFP inhibits cell proliferation in a dose- and time-dependent manner and decreased PCNA and Ki-67 levels in lupus MRL/lpr mice. TFP arrested the cell cycle in the G0/G1 phase, down-regulating cyclin D1, CDK2, and CDK4, and up-regulating p21 expression in a dose-dependent manner. In addition, TFP inhibited p-AKT and p-JNK, possibly by suppressing the activation of PI3K/AKT and JNK/MAPK signaling pathways. TFP treatment remarkably reduced the levels of serum creatinine (Cr) in lupus mice. CONCLUSIONS TFP exhibits inhibitory activity against mesangial cells in vivo and in vitro, which is associated with G1 cell cycle arrest by inactivation of PI3K/AKT and JNK/MAPK signaling pathways. These results suggest the potential of TFP in treatment of mesangial proliferative diseases.

Spatiotemporal variations and risk assessment of estrogens in the water of the southern Bohai Sea: A comprehensive investigation spanning three years.

The ubiquitous and adverse effects of estrogens have aroused global concerns. Natural and synthetic estrogens in 255 water samples from the southern Bohai Sea were analyzed over three years. Total estrogen concentrations were 11.0-268 ng/L in river water and 1.98-99.7 ng/L in seawater, with bisphenol A (BPA) and 17α-ethynylestradiol (EE2) being the predominant estrogens, respectively. Estrogen showed the highest concentrations in summer 2018, followed by spring 2021 and spring 2019, which was consistent with the higher estrogen flux from rivers during summer. Higher estrogen concentrations in 2021 than in 2019 were driven by the higher level of BPA, an additive used in personal protective equipment. Estrogen exhibited higher concentrations in the southern coast of the Yellow River Delta and the northeastern coast of Laizhou bay due to the riverine input and aquaculture. Estrogens could disturb the normal endocrine activities of organisms and edict high ecological risks (90th simulated RQT > 1.0) to aquatic organisms, especially to fish. EE2 was the main contributor of estrogenic potency and ecological risk, which requires special concern. This is the first comprehensive study of estrogen spatiotemporal variations and risks in the Bohai Sea, providing insights into the environmental behavior of estrogens in coastal regions.

Effects of seasonal deposition-erosion cycle on sedimentary organic carbon remineralization and oxygen consumption in a large-river delta-front estuary.

Seasonal sediment deposition-erosion events are dominant drivers of particle-solute dynamics in large-river delta-front estuaries (LDEs), but their influence on elemental cycles is not yet fully understood. To better constrain the role of deposition-erosion events on elemental cycling in LDEs, benthic fluxes of dissolved inorganic carbon (DIC), oxygen, and pore-water solute profiles were measured over different seasons in the Changjiang LDE. Benthic DIC efflux (23.4 ± 6.0 mmol C m-2 d-1) was greater than oxygen influx (7.5 ± 2.0 mmol O2 m-2 d-1) in summer but less in winter (7.7 ± 1.2 mmol C m-2 d-1 and 10.1 ± 1.5 mmol O2 m-2 d-1, respectively). The additional oxygen consumption in sediments in winter was likely due to the oxidation of inorganic diagenetic reductive products (IDRP) (e.g., NH4+, Fe2+, and Mn2+) in deeper sediments exposed by erosion, which resulted in the development of an "oxygen debt". Sedimentary oxygen respiration accounted for at least 48 % of total oxygen consumption (oxygen consumption in both water column and sediment) in winter and was significantly greater than in summer (∼15 %); this highlighted the importance of winter sediment erosion in oxygen depletion. In addition to IDRP oxidation, the remineralization of resuspended sedimentary organic carbon in water column also contributed to the oxygen consumption. The global dataset on benthic DIC and oxygen fluxes provides evidence that the "oxygen debt" is likely to be widespread in LDEs, exerting a significant impact on global carbon and oxygen cycling.

Identification and verification of prognostic cancer subtype based on multi-omics analysis for kidney renal papillary cell carcinoma.

Background: Identifying Kidney Renal Papillary Cell Carcinoma (KIRP) patients with high-risk, guiding individualized diagnosis and treatment of patients, and identifying effective prognostic targets are urgent problems to be solved in current research on KIRP. Methods: In this study, data of multi omics for patients with KIRP were collected from TCGA database, including mRNAs, lncRNAs, miRNAs, data of methylation, and data of gene mutations. Data of multi-omics related to prognosis of patients with KIRP were selected for each omics level. Further, multi omics data related to prognosis were integrated into cluster analysis based on ten clustering algorithms using MOVICS package. The multi omics-based cancer subtype (MOCS) were compared on biological characteristics, immune microenvironmental cell abundance, immune checkpoint, genomic mutation, drug sensitivity using R packages, including GSVA, clusterProfiler, TIMER, CIBERSORT, CIBERSORT-ABS, quanTIseq, MCPcounter, xCell, EPIC, GISTIC, and pRRophetic algorithms. Results: The top ten OS-related factors for KIRP patients were annotated. Patients with KIRP were divided into MOCS1, MOCS2, and MOCS3. Patients in the MOCS3 subtype were observed with shorter overall survival time than patients in the MOCS1 and MOCS2 subtypes. MOCS1 was negatively correlated with immune-related pathways, and we found global dysfunction of cancer-related pathways among the three MOCS subtypes. We evaluated the activity profiles of regulons among the three MOCSs. Most of the metabolism-related pathways were activated in MOCS2. Several immune microenvironmental cells were highly infiltrated in specific MOCS subtype. MOCS3 showed a significantly lower tumor mutation burden. The CNV occurrence frequency was higher in MOCS1. As for treatment, we found that these MOCSs were sensitive to different drugs and treatments. We also analyzed single-cell data for KIRP. Conclusion: Based on a variety of algorithms, this study determined the risk classifier based on multi-omics data, which could guide the risk stratification and medication selection of patients with KIRP.

Study on the role of AlOOH in fluorescence correction and depth purification of Cyclops water.

Protein-like substances produced by biochemical reactions after disinfection of Zooplankton like Cyclops and humic substances in natural water are the main components of NOM (Natural organic matter). To eliminate early warning interference in the fluorescence detection of organic matter in natural water, a clustered flower-like AlOOH (aluminum oxide hydroxide) sorbent was prepared. HA (humic acid) and amino acids were selected as mimics of humic substances and protein-like substances in natural water. The results demonstrate that the adsorbent can selectively adsorb HA from the simulated mixed solution and restore the fluorescence properties of tryptophan and tyrosine. Based on these results, a stepwise fluorescence detection strategy was developed and used in natural water rich in zooplanktonic Cyclops. The results show that the established stepwise fluorescence strategy can well overcome the interference caused by fluorescence quenching. The sorbent was also used for water quality control to enhance coagulation treatment. Finally, trial runs of the water plant demonstrated its effectiveness and suggested a potential control method for early warning and monitoring of water quality.

Fabrication of γ-Al2O3 Nanoarrays on Aluminum Foam Assisted by Hydroxide for Monolith Catalysts.

Heat distribution and good adhesion of the washcoat on monolith catalysts are critical to improving catalytic activity and long-term stability. Compared with cordierite, metal foam presents a high thermal conductivity coefficient. Also, the availability of "washcoat" in situ grown on metal substrates opens the door to eliminating the problem of coating peeling. Generally, hydrothermal or thermal methods are used for the fabrication of in situ grown washcoat on metal substrates. In this research, the aluminum foam monolith vertically aligned Al2O3 nanowire array is successfully prepared at ambient temperature in an alkaline solution for the first time. Furthermore, the Pt-loaded Al2O3 nanowire array (0.5 gPt/L monolith) is applied to C2H4 degradation. The catalyst converts 90% C2H4 at 147 °C with a gas hourly space velocity (GHSV) of 20,000 h-1. And a little decrease (1%) is observed in catalytic activity, even in 15 vol % water vapors. The catalysts show good thermal stability and water resistance property over 36 h at 300 °C. Above all, this study presents a simple way of in situ growth of washcoat on metal-substrate monolith with potentially scaled manufacturing. And the monolith catalyst shows good catalytic performance on C2H4, which can be applied for volatile organic compound treatment.

Comprehensive profiling of the distribution, risks and priority of pharmaceuticals and personal care products: A large-scale study from rivers to coastal seas.

Pharmaceuticals and personal care products (PPCPs) have captured global concern due to their detrimental effects on aquatic organisms. Thirty PPCPs were analyzed in the water of the Jiaozhou Bay watershed, the Yellow Sea (YS) and the East China Sea (ECS) in China to investigate the distribution and risk of PPCPs from rivers to coastal seas, which are not yet well documented. The results showed the prevalence of the target PPCPs with a downward trend in detection frequencies and total concentrations from rivers (675 ng/L on average) to bay (166 ng/L) and to coastal seas (103 ng/L). Antibiotics and personal care products (PCPs) were dominated by amoxicillin (AMOX) and p-hydroxybenzoic acid, respectively, while the dominant estrogens were inconsistent in different regions. Spatially, the total PPCP concentrations were higher in the ECS than that in the YS due to the larger quantity of sewage flowing into the ECS. Additionally, higher total PPCP concentrations were appeared in the southeastern waters outside the Yangtze estuary and Hangzhou Bay of the ECS. The PPCP mixtures might pose medium to high risk to aquatic organisms in general. The total risk quotient (RQT) of antibiotics and PCPs to algae was higher than that to crustacean and fish, while estrogens may cause the greatest damage to fish. Despite the higher PPCP concentrations in river water than in seawater, the RQT of PPCPs in bay water was generally higher than that in river water, which may be associated with the susceptibility of marine organisms. Furthermore, the high-risk pollutants that need special concern in different regions were clarified, showing that AMOX, 17ß-estradiol, and estriol deserve the highest-priority in rivers, bay, and coastal waters, respectively.

Detection, occurrence, influencing factors and environmental risks of paralytic shellfish toxins in seawater in a typical mariculture bay.

Paralytic shellfish toxins (PSTs) producing algae are widely distributed in the global coastal aquatic environment, posing a threat to coastal ecosystem health and mariculture safety. However, the levels and potential environmental risks of PSTs frequently detected in shellfish remain largely unexplored in seawater of mariculture zones. In this study, a new method for trace detection of 13 common PSTs (<1.0 ng/L) in seawater was established based on off-line solid phase extraction (SPE) and on-line SPE-liquid chromatography-tandem mass spectrometry (on-line SPE-LC-MS/MS), and a systematic investigation of PSTs in seawater of the Laizhou Bay, a typical aquaculture bay in China, was conducted to understand their pollution status, environmental impact factors and ecological risks for the first time. Eleven PSTs were detected in the seawater of Laizhou Bay with total concentrations ranging from 0.75 to 349.47 ng/L (mean, 176.27 ng/L), which indicates the rich diversity of PSTs in the mariculture bay and demonstrates the reliability of the proposed analytical method. C1, C2, GTX2, GTX3, dcGTX2, and dcGTX3 were found to be the predominant PSTs, which refreshed the knowledge of PST contamination in the coastal aquatic environment. PST levels in seawater exhibited the highest levels in the southeastern mouth of Laizhou Bay and decreased toward the inner bay. Correlation analyses showed that climatic factors, nutrient status and hydrological conditions had significant effects on the distribution of PST in mariculture bay. Preliminary environmental risk assessments revealed that aquatic organisms throughout the waters of Laizhou Bay are at risk of chronic PST toxicity. These findings imply that the risk of PST in seawater of mariculture bay has previously been grossly underestimated, and that the coastal aquatic environment in North China and even the world may be at more serious risk of PST pollution, which should be taken seriously.

Watershed seasonality regulating vanadium concentrations and ecological risks in the coastal aquatic habitats of the northwest Pacific.

Vanadium is a component of different natural and industrial products and a widely used metal, which, nonetheless, has only garnered attention in recent years owing to its potential risks. Six sampling trips were conducted over different seasons and years, collecting 108 samples from rivers and 232 from the bays and analyzed using high-precision inductively coupled plasma mass spectrometry. This study investigated the sources, spatiotemporal characteristics, and risks of vanadium in the aquatic ecosystems of two typical bays of the Northwest Pacific that have strong links with vanadium-related industries. Likewise, the health and ecological risks were assessed using probabilistic and deterministic approaches. Overall, vanadium concentrations were higher in Jiaozhou Bay (JZB: 0.41-52.7 µg L-1) than in Laizhou Bay (LZB: 0.39-17.27 µg L-1), with concentrations higher than the majority of the worldwide studies. Vanadium-realted industries significantly impacted (p < 0.05) the metal concentrations in the rivers with 54.22% (40.73-150%) and 54.45% (27.66%-68.87%) greater concentrations in JZB and LZB rivers. In addition, vanadium exhibited significant seasonal variation, and higher values were quantified during the monsoon period at LZB owing to the greater catchment area. Impacted by smaller freshwater inputs, the post-monsoon period had substantial impacts on JZB, and vanadium in the rivers and bays was significantly higher during the winter. Despite some concentrations being higher than that indicated in the drinking water guidelines established by China, vanadium presents low to null risks to the population as per both approaches. Last, species with limited resilience are likely to face medium to high risks, with an incidence of 65-93% using the probabilistic method and 52-97% using the deterministic assessment.

Occurrence, geochemical characteristics, enrichment, and ecological risks of rare earth elements in sediments of "the Yellow river-Estuary-bay" system.

Recent studies have suggested that rare earth elements (REEs) are contaminants of emerging concern. Moreover, the understanding of the occurrence and risks of REEs in river-estuary-bay systems is limited. The present study investigated the distributions, geochemical characteristics, and ecological risks of Y and 14 REEs (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) in sediments from the Yellow River to its estuary and adjacent Laizhou Bay. The average total concentrations of Y and REEs in the sediments generally increased from the Yellow River (149 mg/kg) to the estuary (165 mg/kg) and Laizhou Bay (173 mg/kg). In the estuarine core sediments, the concentrations of Y, light REEs (LREEs), and heavy REEs (HREEs) were in the ranges of 19.5-31.4 mg/kg, 58.6-156 mg/kg, and 12.3-19.1 mg/kg, respectively, from the 1700s to 2018, showing no obvious increasing or decreasing trends. The surface and core sediments from the river to the bay were characterized by obvious fractionation between LREEs and HREEs. In sediments, Fe minerals and clay are believed to promote the accumulation of REEs, especially HREEs. The enrichment levels of REEs generally increased from the middle reaches of the Yellow River to the bay, and Gd, Tb, Dy, Ho, Yb, and Lu were the most enriched elements in the sediments. Lu had moderate potential ecological risks in sediments of "the Yellow River-estuary-bay" system, and other REEs had relatively low ecological risks. The potential ecological risk indices of Y and REEs ranged from 78.7 to 144, showing increasing trends from the Yellow River to its estuary and adjacent bay, which should raise concerns regarding emerging contaminant management around estuarine and coastal regions.

Spatiotemporal variations and the ecological risks of organophosphate esters in Laizhou Bay waters between 2019 and 2021: Implying the impacts of the COVID-19 pandemic.

Organophosphate esters (OPEs) are a group of synthetic chemicals used in numerous consumer products such as plastics and furniture. The Coronavirus Disease 2019 (COVID-19) pandemic significantly slowed anthropogenic activities and reduced the emissions of pollutants. Meanwhile, the mismanagement of large quantities of disposable plastic facemasks intensified the problems of plastic pollution and leachable pollutants in coastal waters. In this study, the joint effects of the COVID-19 outbreak on the occurrence of 12 targeted OPEs in the waters of Laizhou Bay (LZB) were investigated. The results showed that the median total OPE concentrations were 725, 363, and 109 ng L-1 in the sewage treatment plant effluent, river water, and bay water in 2021, decreased significantly (p < 0.05) by 67%, 68%, and 70%, respectively, compared with those before the COVID-19 outbreak. The release potential of targeted OPEs from disposable surgical masks in the LZB area was ∼0.24 kg yr-1, which was insufficient to increase the OPE concentration in the LZB waters. The concentrations of most individual OPEs significantly decreased in LZB waters from 2019 to 2021, except for TBOEP and TNBP. Spatially, a lower concentration of OPEs was found in the Yellow River estuary area in 2021 compared with that before the COVID-19 pandemic due to the high content of suspended particulate matter in the YR. A higher total OPE concentration was observed along the northeastern coast of LZB, mainly owing to the construction of an artificial island since 2020. The ecological risks of the OPE mixture in LZB waters were lower than those before the COVID-19 outbreak. However, TCEP, TNBP, and BDP should receive continuous attention because of their potential ecological risks to aquatic organisms.

Spatial distributions and environmentally-mediated factors of dimethylsulfoxide off the northern Antarctic Peninsula in summer.

Spatial distributions of dissolved and particulate dimethylsulfoxide (DMSOd and DMSOp) were investigated off the northern Antarctic Peninsula during the austral summer of 2018, an ecologically and climatically important region of the world. In the upper waters, DMSOd was concentrated in the ice-melt zone because DMSO functions physiologically as an intracellular osmolyte and cryoprotectant. DMSOd concentrations had a weak positive correlation with temperature but a negative correlation with nutrients. This highlighted the importance of temperature-dependent biological activities and photolysis in DMSOd production and the important role of the intracellular antioxidation system in phytoplankton cells. The decrease of average DMSOp:Chl-a ratios in upper waters from west to east, along with decreasing temperatures and increasing diatoms proportions in the phytoplankton, illustrates how seawater DMSO production capacities depend on ambient temperatures and the composition of phytoplankton assemblages. DMSOp were accumulated in deep waters through bio-debris accumulation and microbial activity.

Prevalence of the neurotoxin domoic acid in the aquatic environments of the Bohai and Northern Yellow seas in China.

Domoic acid (DA), a natural marine phytotoxin produced by toxigenic algae, is harmful to fishery organisms and the health of seafood consumers. In this study, we performed a whole-sea area investigation of DA in seawater, suspended particulate matter (SPM), and phytoplankton of the Bohai and Northern Yellow seas to clarify the occurrence, phase partitioning, spatial distribution, potential sources, and environmental influencing factors of DA in the aquatic environment. DA in different environmental media was identified using liquid chromatography-high resolution mass spectrometry and liquid chromatography-tandem mass spectrometry. DA was found to be predominantly in a dissolved phase (99.84 %) in seawater with only 0.16 % in SPM. Dissolved DA (dDA) was widely detected in nearshore and offshore areas of the Bohai Sea, Northern Yellow Sea, and Laizhou Bay with concentrations ranging from < limits of detection (LOD) to 25.21 ng/L (mean: 7.74 ng/L), < LOD to 34.90 ng/L (mean: 16.91 ng/L), and 1.74 ng/L to 38.20 ng/L (mean: 21.28 ng/L), respectively. dDA levels were relatively lower in the northern part than in the southern part of the study area. In particular, the dDA levels in the nearshore areas of Laizhou Bay were significantly higher than in other sea areas. This may be due to seawater temperature and nutrient levels exerting a crucial impact on the distribution of DA-producing marine algae in Laizhou Bay during early spring. Pseudo-nitzschia pungens may be the main source of DA in the study areas. Overall, DA was prevalent in the Bohai and Northern Yellow seas, especially in the nearshore aquaculture zone. Routine monitoring of DA in the mariculture zones of the northern seas and bays of China should be performed to warn shellfish farmers and prevent contamination.