Tumor Microenvironment-Activatable Phototheranostic: Leveraging Nitric Oxide and Weak Acidity as Dual Biomarkers for Ratiometric Fluorescence, Photoacoustic Imaging, and Photothermal Therapy.

Tumor microenvironment-responsive phototheranostic agents are highly sought after for their ability to improve diagnostic accuracy and treatment specificity. Here, we introduce a novel single-molecule probe, POZ-NO, which is activated by nitric oxide (NO) and weak acidity, enabling dual-mode imaging and photothermal therapy (PTT) of tumors. In acidic environments with elevated NO levels, POZ-NO exhibits a distinctive ratiometric fluorescence signal shift from the red to near-infrared, accompanied by a 700 nm photoacoustic signal. Additionally, POZ-NO demonstrated potent photothermal effects upon NO and acidity activation, achieving an impressive conversion efficiency of 74.3% under 735 nm laser irradiation. In vivo studies confirm POZ-NO's ability to accurately image tumors through ratiometric fluorescence and photoacoustic modes while selectively treating tumors with PTT.

Selenium increases antimony uptake in ramie (Boehmeria nivea L.) by enhancing the physiological, antioxidative, and ionomic mechanisms.

Ramie (Boehmeria nivea L.) is a promising phytoremediation candidate due to its high tolerance and enrichment capacity for antimony (Sb). However, challenges arise as Sb accumulated mainly in roots, complicating soil extraction. Under severe Sb contamination, the growth of ramie may be inhibited. Strategies are needed to enhance Sb accumulation in ramie's aboveground parts and improve tolerance to Sb stress. Considering the beneficial effects of selenium (Se) on plant growth and enhancing resistance to abiotic stresses, this study aimed to investigate the potential use of Se in enhancing Sb uptake by ramie. We investigated the effects of Se (0.5, 1, 2, 5, or 10 µM) on ramie growth, Sb uptake and speciation, antioxidant responses, and ionomic profiling in ramie under 10 mg/L of SbIII or antimonate (SbV) stresses. Results revealed that the addition of 0.5 µM Se significantly increased shoot biomass by 75.73% under SbIII stress but showed minimal effects on shoot and root length in both SbIII and SbV treatments. Under SbIII stress, 2 µM Se significantly enhanced Sb concentrations by 48.42% in roots and 62.88% in leaves. In the case of SbV exposure, 10 µM Se increased Sb content in roots by 42.57%, and 1 µM Se led to a 91.74% increase in leaves. The speciation analysis suggested that Se promoted the oxidation of SbIII to less toxic SbV to mitigate Sb toxicity. Additionally, Se addition effectively minimized the excess reactive oxygen species produced by Sb exposure, with the lowest malondialdehyde (MDA) content at 0.5 µM Se under SbIII and 2 µM Se under SbV, by activating antioxidant enzymes including superoxide dismutase, catalase, peroxidase, and glutathione peroxidase. Ionomic analysis revealed that Se helped in maintaining the homeostasis of certain nutrient elements, including magnesium, potassium (K), calcium (Ca), iron (Fe), and copper (Cu) in the SbIII-treated roots and K and manganese (Mg) in the SbV-treated roots. The results suggest that low concentrations of Se can be employed to enhance the phytoremediation of Sb-contaminated soils using ramie.

Biodegradation of high molecular weight polycyclic aromatic hydrocarbons by Sarocladium terricola strain PYR-233 isolated from petrochemical contaminated sediment.

Polycyclic aromatic hydrocarbons (PAHs) were frequently found in sediment and were primarily treated through microbial degradation. Thus, efficient management of PAH pollution requires exploring the molecular degradation mechanisms of PAHs and expanding the pool of available microbial resources. A fungus (identified as Sarocladium terricola strain RCEF778) with the remarkable ability to degrade pyrene was screened from sediment near a petrochemical plant, and its growth and pyrene degradation characteristics were comprehensively investigated. The results showed that the fungus exhibited great effectiveness in pyrene degradation, with a degradation ratio of 88.97% at 21 days at the conditions: 35 °C, pH 7, 10 mg L-1 initially pyrene concentration, 3% supplementary salt, and glucose supplementation. The generation and concentration variation of the intermediate products were identified, and the results revealed that the fungus degraded pyrene through two pathways: by salicylic acid and by phthalic acid. Three sediments (M1, M2, M3), each exhibiting different levels of PAH pollution, were employed to examine the effectiveness of fungal degradation of PAHs in practical sediment samples. These data showed that with the fungus, the degradation ratios ranged from 13.64% to 23.50% for 2-3 rings PAHs, 40.93%-49.41% for 4 rings PAHs, and 39.59%-48.07% for 5-6 rings PAHs, which were significantly higher than those for the sediment without the fungus and confirmed the excellent performance of the fungal. Moreover, the Gompertz model was employed to analyze the degradation kinetics of 4-rings and 5-6 rings PAHs in these sediments, and the results demonstrated that the addition of the fungus could significantly increase the maximum degradation ratio, degradation start-up rate and maximum degradation rate of 4-rings and 5-6 rings PAHs and shorten the time required to reach the maximum degradation rate. This study not only supplied fungal materials but also established crucial theoretical foundations for the development of bioremediation technologies aimed at high molecular weight PAH-contaminated sediments.

Research progress and perspective on sludge anaerobic digestion technology: A bibliometric analysis.

Rational disposal of sludge is an ongoing concern. This work is the first attempt for in-depth statistical analysis of anaerobic digestion (AD) research in recent three decades (1986-2022) using both quantitative and qualitative approaches in bibliometrics to investigate the research progress, trends and hot spots. All publications in the Web of Science Core Collection database from 1986 to April 4, 2022 were analyzed. Results showed that the research on AD started in 1999 and the number of papers significantly increased since 2012. The research about the disposal of sewage sludge mainly focuses on energy recovery (e.g. methane and short chain volatile organic acids) by AD. Besides, different pretreatment technologies were studied in this study to eliminate the negative effects on the disposal of sludge caused by hydrolysis (rate-limiting step of AD), water content (increasing the costs) and heavy metal (toxic to the environment) of sludge. Of those, the treatment technologies related to direct interspecies electron transfer were worth further studied in the future. Towards that end, iron conductive material, iron-based advanced oxidation and biological treatment were concluded as the prospective technologies and worth to further study.

Construction of a Dual-Functional, Reversible, Ratiometric, Golgi-Targeting Fluorescent Probe for Real-time Monitoring of Dynamics of Intracellular Redox Homeostasis.

Intracellular redox homeostasis is highly important for the physiological processes of living organisms. Real-time monitoring of the dynamics of this intracellular redox process is pivotal but challenging because the biological redox reactions involved in the process are reversible and require at least one pair of oxidizing and reducing species. Thus, biosensors for investigating intracellular redox homeostasis need to be dual-functional, reversible, and, ideally, ratiometric in order for them to have real-time monitoring capacity and to provide accurate imaging information. In light of the importance of the redox pair between ClO- and GSH in living organisms, herein, we used the phenoselenazine (PSeZ) moiety as an electron donor and a reaction site to design a coumarin-based fluorescent probe, PSeZ-Cou-Golgi. After successive treatment with ClO- and GSH, the probe PSeZ-Cou-Golgi experienced an oxidation of selenium (Se) to selenoxide (Se═O) by ClO- and a subsequent reduction of Se═O to Se by GSH. The redox reactions alternatively changed the electron-donating strength of the donor in the probe PSeZ-Cou-Golgi, in turn affecting the intramolecular charge transfer process that resulted in the reversible, ratiometric change of fluorescence from red to green. After four cycles of reversible ClO-/GSH detection during in vitro experiments, the probe PSeZ-Cou-Golgi still had good performance. With the Golgi-targeting group, the probe PSeZ-Cou-Golgi was able to monitor the dynamic change of the ClO-/GSH-mediated redox state during Golgi oxidative stress, making it a versatile molecular tool. More importantly, the probe PSeZ-Cou-Golgi could facilitate the imaging of the dynamic redox state during acute lung injury progression.

Carbon Monoxide: A Second Biomarker to Couple with Viscosity for the Construction of "Dual-Locked" Near-Infrared Fluorescent Probes for Accurately Diagnosing Non-Alcoholic Fatty Liver Disease.

Nonalcoholic fatty liver disease (NAFLD) can progress to cirrhosis and liver cancer if left untreated. Therefore, it is of great importance to develop useful tools for the noninvasive and accurate diagnosis of NAFLD. Increased microenvironmental viscosity was considered as a biomarker of NAFLD, but the occurrence of increased viscosity in other liver diseases highly reduces the diagnosis accuracy of NAFLD by a single detection of viscosity. Hence, it is very necessary to seek a second biomarker of NAFLD. It has been innovatively proposed that the overexpressed heme oxygenase-1 enzyme in NAFLD would produce abnormally high concentrations of CO in hepatocytes and that CO could serve as a potential biomarker. In this work, we screened nine lactam Changsha dyes (HCO-1-HCO-9) with delicate structures to obtain near-infrared (NIR), metal-free, and "dual-locked" fluorescent probes for the simultaneous detection of CO and viscosity. Changsha dyes with a 2-pyridinyl hydrazone substituent could sense CO, and the 5-position substituents on the 2-pyridinyl moiety had a great electron effect on the reaction rate. The double bond in these dyes served as the sensing group for viscosity. Probe HCO-9 was utilized for precise diagnosis of NAFLD by simultaneous detection of CO and viscosity. Upon reacting with CO in a high-viscosity microenvironment, strong fluorescence at 745 nm of probe HCO-9 was turned on with NIR excitation at 700 nm. Probe HCO-9 was proven to be an effective tool for imaging CO and viscosity. Due to the advantages of NIR absorption and low toxicity, probe HCO-9 was successfully applied to image NAFLD in a mouse model.

Biotransformation and detoxification mechanism of inorganic arsenic in a freshwater benthic fish Tachysurus fulvidraco with dietborne exposure.

Inorganic arsenic (iAs) is a pervasive environmental toxin, its metabolism and detoxification mechanism in freshwater benthic fish under dietary exposure remain unknown. In this study, dietborne exposure of two iAs (arsenate (AsV) and arsenite (AsIII)) was conducted for yellow catfish (Tachysurus fulvidraco) to investigate the bioaccumulation, biotransformation, and detoxification of iAs in the fish liver. The results showed that As significantly accumulated in both the AsIII and AsV treatments compared to the control, and the final As concentration was comparable for both treatments. The detoxification of iAs in freshwater fish depends on the degree of arsenic methylation and the level of antioxidants. Both reduction processes of AsV to AsIII and oxidation processes of AsIII to AsV were found in AsV and AsIII treatments. The major-low toxicity intermediates, which also are detoxification products in the AsIII treatment, were pentavalent dimethylarsinic acid and arsenobetaine (AsB), and AsB was major-low toxicity intermediate in the AsV treatment. Both antioxidants glutathione and glutathione S-transferase contribute to the detoxification of iAs by scavenging excessive reactive oxygen species and promoting iAs methylation in yellow catfish under iAs exposure.

The crucial elements for lettuce (Lactuca sativa L.) growth under DMA stress and the linkage with DMA behavior: A new application of ionome.

Dimethylarsinic acid (DMA) is one of the common arsenic (As) species present in soil and is more toxic to plants than others. Identifying the crucial elements for plant growth under DMA stress is essential to enhance plant tolerance to DMA. Herein, we provided for the first time an ionome-based approach to address this issue. The phenotype, As species and concentrations of 11 essential elements in lettuce tissues were monitored under exposures of 0.1, 0.5, 1, 2, 5 mg L-1 DMA in hydroponic culture for 32 days. Lettuces remained normal (no significant difference in phenotype from the control) under 0.1-2 mg L-1 DMA stress, and were inhibited with fresh weights of leaf and root under 5 mg L-1 DMA stress. Integrating the difference in ionome profiles between the two growth states (normal and inhibited) and the responses of the individual element, Mg and S were clarified as the most possible candidates for the crucial elements for lettuce growth under DMA stress. Under 5 mg L-1 DMA stress, the accumulation of Mg and S declined, yet their BCF values were significantly increased, which was consistent with the change in BCF of DMA. Based on the physiological functions of Mg and S and the toxicity of DMA, it could be inferred that the enhanced transfer of Mg and S to leaves should be induced by the potential damage caused by the increased DMA accumulation in leaves, and would result in a shortage of both elements in roots as well as the growth inhibition.

Revealing the key species for pyrene degradation in Vallisneria natans rhizosphere sediment via triple chamber rhizome-box experiments.

To identify key species associated with pyrene degradation in Vallisneria natans (V.natans) rhizosphere sediment, this work investigated the temporal and spatial changes in the rhizosphere microbial community and the relationship between the changes and the pyrene degradation process through a three-compartment rhizome-box experiment under pyrene stress. The degradation kinetics of pyrene showed that the order of degradation rate was rhizosphere > near-rhizosphere > non-rhizosphere. The difference in the pyrene degradation behavior in the sediments corresponded to the change in the proportions of dominant phyla (Firmicutes and Proteobacteria) and genera (g_Massilia f_Comamonadaceae, g_Sphingomonas). The symbiosis networks and hierarchical clustering analysis indicated that the more important phyla related to the pyrene degradation in the rhizosphere was Proteobacteria, while g_Sphigomonas, f_Comamonadaceae, and especially g_Massilia were the core genera. Among them, f_Comamonadaceae was the genus most affected by rhizosphere effects. These findings strengthened our understanding of the PAHs-degradation microorganisms in V.natans rhizosphere and are of great significance for enhancing phytoremediation on PAHs-contaminated sediment.

Transcriptomic analysis reveals the molecular mechanisms of Boehmeria nivea L. in response to antimonite and antimonate stresses.

Soil antimony (Sb) pollution is a global concern that threatens food security and human health. Boehmeria nivea L. (ramie) is a promising phytoremediation plant exhibiting high tolerance and enrichment capacity for Sb. To reveal the molecular mechanisms and thus enhance the ramie uptake, transport, and detoxification of Sb with practical strategies, a hydroponic experiment was conducted to compare the physiological and transcriptomic responses of ramie towards antimonite (Sb(Ⅲ)) and antimonate (Sb(Ⅴ)). Phenotypic results showed that Sb(Ⅲ) had a stronger inhibitory effect on the growth of ramie. Root Sb content under Sb(Ⅲ) was 2.43 times higher than that in Sb(Ⅴ) treatment. Based on the ribonucleic acid sequencing (RNA-Seq) technique, 3915 and 999 significant differentially expressed genes (DEGs) were identified under Sb(Ⅲ) and Sb(Ⅴ), respectively. Transcriptomic analysis revealed that ramie showed different adaptation strategies to Sb(Ⅲ) and Sb(V). Key DEGs and their involved pathways such as catalytic activity, carbohydrate metabolisms, phenylpropanoid biosynthesis, and cell wall modification were identified to perform crucial roles in Sb tolerance and detoxification. Two heavy metal-associated domain-type genes, six heavy metal-associated isoprenylated plant proteins, and nine ABC transporters showed possible roles in the transport and detoxification of Sb. The significant upregulation of NRAMP5 and three NIPs suggested their roles in the transport of Sb(V). This study is the basis for future research to identify the exact genes and biological processes that can effectively enhance Sb accumulation or improve plant tolerance to Sb, thereby promoting the phytoremediation of Sb-polluted soils.

Uptake, tolerance, and detoxification mechanisms of antimonite and antimonate in Boehmeria nivea L.

Boehmeria nivea L. (ramie) is a promising phytoremediation plant for antimony (Sb)-contaminated soils. However, the uptake, tolerance, and detoxification mechanisms of ramie to Sb, which are the basis for finding efficient phytoremediation strategies, remain unclear. In the present study, ramie was exposed to 0, 1, 10, 50, 100, and 200 mg/L of antimonite (Sb(III)) or antimonate (Sb(V)) for 14 days in hydroponic culture. The Sb concentration, speciation, subcellular distribution, and antioxidant and ionomic responses in ramie were investigated. The results illustrated that ramie was more effective in the uptake of Sb(III) than Sb(V). Most of the Sb accumulated in ramie roots, with the highest level reaching 7883.58 mg/kg. Sb(V) was the predominant species in leaves, with 80.77-96.38% and 100% in the Sb(III) and Sb(V) treatments, respectively. Immobilization of Sb on the cell wall and leaf cytosol was the primary mechanism of accumulation. Superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) contributed significantly to root defense against Sb(III), while CAT and glutathione peroxidase (GPX) were the major antioxidants in leaves. CAT and POD played crucial roles in the defense against Sb(V). B, Ca, K, Mg, and Mn in Sb(V)-treated leaves and K and Cu in Sb(III)-treated leaves may be related to the biological processes of Sb toxicity mitigation. This study is the first to investigate the ionomic responses of plants toward Sb and could provide valuable information for the phytoremediation of Sb-polluted soils.

Advanced treatment of secondary effluent by the integration of heterogeneous catalytic ozonation and biological aerated filter.

The advanced treatment of secondary effluents was investigated by employing heterogeneous catalytic ozonation integrated with a biological aerated filter (BAF) process. The results indicated that catalytic ozonation with the prepared catalyst (MnxCuyOz/γ-Fe2O3) significantly enhanced the performance of pollutant removal and broke up macromolecules into molecular substances by the generated hydroxyl radicals. These molecular substances were easily absorbed by microorganisms in the microbial membrane reactor. In the BAF process, chemical oxygen demand (COD) (chemical oxygen demand) decreased from 54.26 to 32.56 mg/L, while in catalytic ozonation coupled with the BAF, COD could be reduced to 14.65 mg/L (removal ratio 73%). Under the same condition, NH4+-N decreased from 77.43 to 22.69 mg/L and 15.73 mg/L (removal ratio 70%) in the BAF and the catalytic ozonation coupled with BAF, respectively. In addition, the model that highly correlated influent COD to effluent COD and reactor height for filler could predict the removal ratio of COD of the BAF system. Based on the microbial community analysis, ozone in the solution had a certain screening effect on microorganisms, which helped to better adapt to the ozone-containing environment. Therefore, the integrated process with its efficient, economic, and sustainable advantages was suitable for the advanced treatment of secondary effluents.

Chlorination-induced pKa decrease: an improved strategy to design ratiometric hypochlorite fluorescent probes with ideally high selectivity.

Based on the selective ClO--triggered chlorination reaction and the subsequent pKa decrease of phenols, a new strategy was developed for rationally designing ratiometric ClO- fluorescent probes with high selectivity. By investigating the fluorescence responses of 6-cyano-2-naphthol toward ClO- and the pKa-dependent response mechanism, we developed a rapid, sensitive and selective two-photon ratiometric fluorescent probe, Naph-DFOB, to detect ClO-. This probe displayed a ratiometric fluorescence change (from 509 nm to 628 nm) toward ClO- and was successfully applied to image intracellular ClO- in living cells with two-photon excitation. Using Naph-DFOB as a useful tool, the investigation of lipopolysaccharide (LPS)-induced acute lung injury in a mouse model was effectively performed.

Prediction of pharmaceutical and personal care products elimination during heterogeneous catalytic ozonation via chemical kinetic model.

Prediction of the removal of pollutants is important for the process design and optimization of wastewater treatment. In this study, the heterogeneous catalytic ozonation chemical kinetic model based on reaction kinetic constants between O3 (and •OH) and pollutants, and pseudo-first order rate constants for pollutant adsorption was established. The model parameters were obtained via O3 and p-chlorobenzonic acid decay curves, and adsorption kinetic experiments, respectively. Higher •OH exposures were obtained at the expense of lower O3 exposures during catalytic ozonation compared to simple ozonation. Importantly, the experimentally measured and model-predicted removal ratios correlated well in all reaction systems, with correlation coefficients above 0.950 in synthetic solution and 0.893-0.979 in secondary effluent. Furthermore, the model revealed that pollutants were degraded mainly by O3 and/or •OH oxidation during catalytic ozonation, while adsorption of pollutants on catalysts contributed negligibly. Hence, the degradation ratios of pollutants could be satisfactorily predicted using the simplified model based only on the O3 and •OH exposures in the heterogeneous catalytic ozonation systems with low adsorption capacity catalysts.

Catalytic ozonation of chloramphenicol with manganese-copper oxides/maghemite in solution: Empirical kinetics model, degradation pathway, catalytic mechanism, and antibacterial activity.

The composite material of manganese-copper oxide/maghemite (MnxCuyOz/γ-Fe2O3) was synthesized by the co-precipitation-calcination method. With the initial concentration of 0.2 g/L MnxCuyOz/γ-Fe2O3 and 10 mg/L O3, the chloramphenicol (CAP, 10 mg/L) could be completely degraded, which was about 2.22 times of that treated with ozonation alone. The contribution of O3 and hydroxyl radical (•OH) for CAP degradation in the catalytic process was 6.9% and 93.1%, respectively. According to the effects of catalyst dosage, ozone dosage, and pH on the catalytic performance of MnxCuyOz/γ-Fe2O3, a predictive empirical model was developed for the ozonation with the MnxCuyOz/γ-Fe2O3 system. The HCO3-/CO32- and phosphates in solution could inhibit the degradation of CAP with the inhibition ratios 8.45% and 13.8%, respectively. The HCO3-/CO32- could compete with CAP and react with •OH, and the phosphates were considered as poisons for catalysts by blocking the surface active sites to inhibit ozone decomposition. The intermediates and possible degradation pathways were detected and proposed. The catalytic ozonation could effectively control the toxicity of the treated solution, but the toxicity was still not negligible. Furthermore, MnxCuyOz/γ-Fe2O3 could be easily and efficiently separated from the reaction system with an external magnet, and it possessed excellent reusability and stability.

Oxygen-deficient Cu doped NiFeO nanosheets hydroxide as electrode material for efficient oxygen evolution reaction and supercapacitor.

The development of renewable energy conversion and storage has triggered the development of electrode materials for oxygen evolution reaction (OER) and supercapacitors. Here we report a highly active Cu doped NiFe nanosheets hydroxide electrode with rich oxygen vacancies (OVs) (denoted as H-NiFeCuO/NF) prepared by in situ anodic electrodeposition on the three-dimensional macroporous nickel foam (NF) substrate followed by heat treatment with H2. The as-prepared H-NiFeCuO/NF electrode showed the initial potential of 1.44 V (versus RHE) for OER and 980 F g-1 specific capacity as supercapacitor in 1 M KOH. Further investigation suggested that the tuning of composition and structure by doping copper ions and creating OVs helped accelerate the electrochemical reactions. This practice provides an efficient approach for the fabrication of heteromultimetallic hydroxide monolithic electrode with high performance in OER or supercapacitor application.

The dynamic changes of arsenic biotransformation and bioaccumulation in muscle of freshwater food fish crucian carp during chronic dietborne exposure.

Dietary uptake is the major way that inorganic arsenic (iAs) enters into benthic fish; however, the metabolic process of dietborne iAs in fish muscle following chronic exposure remains unclear. This was a 40-day study on chronic dietborne iAs [arsenite (AsIII) and arsenate (AsV)] exposure in the benthic freshwater food fish, the crucian carp (Carassius auratus), which determined the temporal profiles of iAs metabolism and toxicokinetics during exposure. We found that an adaptive response occurred in the fish body after iAs dietary exposure, which was associated with decreased As accumulation and increased As transformation into a non-toxic As form (arsenobetaine). The bioavailability of dietary AsIII was lower than that of AsV, probably because AsIII has a lower ability to pass through fish tissues. Dietary AsV exhibited a high potential for transformation into AsIII species, which then accumulated in fish muscle. The largely produced AsIII considered more toxic at the earlier stage of AsV exposure should attract sufficient attention to human exposure assessment. Therefore, the pristine As species and exposure duration had significant effects on As bioaccumulation and biotransformation in fish. The behavior determined for dietborne arsenic in food fish is crucial for not only arsenic ecotoxicology but also food safety.

Rational Design of a Two-Photon Ratiometric Fluorescent Probe for Hypochlorous Acid with a Large Stokes Shift.

By introducing the tetrahydroquinoxaline group as the electron donor to enhance intramolecular charge transfer effect, we deliberately designed a coumarin derivative, TQC-HClO, to serve as a two-photon ratiometric fluorescent probe for imaging hypochlorous acid in cells and zebra fish with good sensitivity and high selectivity. TQC-HClO displayed an obvious two-photon absorbance cross-section (over 100 GM in 800-840 nm), large Stokes shifts (159 to 173 nm), and a ratiometric fluorescence change from orange (λmaxem = 583 nm) to red (λmaxem = 650 nm) in response to hypochlorous acid.

Effects of waterborne exposure to cadmium on biochemical responses in the freshwater gastropod, Bellamya aeruginosa.

The biochemical responses of Bellamya aeruginosa as a dominant and widespread freshwater gastropod throughout China to waterborne cadmium (Cd) were investigated to explore the impacts of exposure concentration and duration in this potential sentinel species. After the 7 days' test of dosage-mortality relationship, gastropods were exposed for either 7 days at the LC50 (1.7 mg/L), the LC10 (0.7 mg/L) and 0.02 mg/L Cd, or 28 days at 0.02 mg/L Cd. A suite of biochemical indicators including metallothionein-like protein (MTLP), reduced glutathione (GSH), catalase (CAT), contents of tissue metal (Cd, Fe, Mn, Cu, Zn), and the compartments of these metals bound to MTLP were examined. The treatment of 0.02 mg/L Cd led to the increase of Cd bound to MTLP (Cd-MTLP) levels, the decrease of GSH content, and the upregulation of CAT activity, but no induction of MTLP, indicating that the intrinsic MTLP and GSH worked together for the detoxification of Cd at the low exposure. When the exposure concentration increased, GSH was depleted severely and synthesis of MTLP was triggered, leading to a strong and significant relationship between MTLP level and Cd accumulation. At the lethal concentrations (1.7 mg/L), both MTLP induction and CAT activity were inhibited while the proportion of Cd-MTLP to total Cd were increased, suggesting more intrinsic MTLP were utilized to sequester free Cd ions. Therefore, the content of Cd-MTLP in digestive glands of B. aeruginosa was recommended as a reliable biomarker for Cd contamination.

Four typical personal care products in a municipal wastewater treatment plant in China: Occurrence, removal efficiency, mass loading and emission.

The occurrence, removal efficiency, mass loading and environmental emission of four categories (benzotriazoles; parabens; antimicrobials; benzophenones) of personal care products were simultaneously determined along the whole process line through an integrated approach (involving both dissolved and adsorbed phase) at a typical wastewater treatment plant in Hunan Province, Southern China. The results showed the prevalence of 13 and 11 target compounds in wastewater and suspended particulate matter, respectively. Twelve substances were detected in the sludge with the mean concentrations ranging from 0.12 to 591.23 ng/g dry weight. Benzotriazoles were the dominant compounds existing in water and antimicrobials were readily being absorbed onto suspended particulate matter and sludge. The overall removal efficiencies of compounds in the total treatment were -84.06%-98.53%. Mass balance results revealed that 85.17%-98.73% of the parabens and benzophenones were removed by degradation, while antimicrobials were removed by being adsorbed onto sludge. However, benzotriazoles could not be efficiently removed and the mass loss was lower than 61.03%. Although ultraviolet radiation played a limited role in removing most target compounds, it still had an impact on removing antimicrobials, 5,6-dimethyl-1H-benzotriazole and 2-hydroxy-4-methoxybenzophenone. The total mass loading and emission of personal care products were 506.35 mg/d/1000 people and 357.56 mg/d/1000 people, respectively. This work would help understand the removal approaches and real pollution of personal care products in the water environment.