ZNT1 Involves Cuproptosis through Regulating MTF1-conduced Expression of MT1X under Copper Overload

Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination.

Environmental Obesogens and Their Perturbations in Lipid Metabolism

Epidemiological data show that obesity is now a pandemic.Lipid homeostasis requires the coordination of multiple tissues and organs,including the liver,kidney,cardiovascular system,and adipose tissues,to maintain bodily homeostasis.As increasing amounts of chemicals are being synthesized,applied,and released into the environment,their obesogenic effects have triggered serious concern.Currently,more than 50 types of chemicals with high human exposure levels have been identified as environmental obesogens that can interfere with lipid metabolism and induce obesity.Experimental studies have shown that the lipid metabolism interference effects of obesogens have multiple targets,including nuclear receptors,transcription factors,cytokines,and hormones.The interfering factors of environmental obesogeninduced obesity include transgenerational effects,susceptibility windows,gender differences,structure−effect relationships,and diet habits.Various research approaches have been established to conduct obesogenic effect research.This comprehensive review summarizes the mechanisms underlying obesogen actions and the research progress on obesogen-disrupted lipid metabolism,along with the influencing factors and research approaches,aiming to provide a framework for understanding the effects of environmental obesogens on lipid metabolism.

Distribution of polycyclic aromatic hydrocarbons in sediments from Yellow River Estuary and Yangtze River Estuary,China

Surface sediment samples collected from twenty-one sites of Yellow River Estuary and Yangtze River Estuary were determined for sixteen priority polycyclic aromatic hydrocarbons （PAHs） by isotope dilution GC-MS method. The total PAH contents varied from 10.8 to 252 ng/g in Yellow River Estuary sediment, and from 84.6 to 620 ng/g in Yangtze River Estuary sediment. The mean total PAH content of Yangtze River Estuary was approximately twofold higher than that of Yellow River Estuary. The main reasons for the difference may be the rapid industrial development and high population along Yangtze River and high silt content of Yellow River Estuary. The evaluation of PAH sources suggested that PAHs in two estuaries sediments estuaries were derived primarily from combustion sources, but minor amounts of PAHs were derived from petroleum source in Yellow River Estuary. PAHs may be primary introduced to Yellow River Estuary via dry/wet deposition, wastewater effluents, and accidental oil spills, and Yangtze River Estuary is more prone to be affected by wastewater discharge.

Cloud point extraction coupled with HPLC-UV for the determination of phthalate esters in environmental water samples

A method based on cloud point extraction was developed to determine phthalate esters including di-ethyl-phthalate （DEP）, di- （2-ethylhexyl）-phthalate （DEHP） and di-cyclohexyl-phthalate （DCP） in environmental water samples using high-performance liquid chromatography separation and ultraviolet detection （HPLC-UV）. The non-ionic surfactant Triton X-114 was chosen as extraction solvent. The parameters affecting extraction efficiency, such as concentrations of Triton X-114 and Na2SO4, equilibration temperature, equilibration time and centrifugation time were evaluated and optimized. Under the optimum conditions, the method can achieve preconcentration factors of 35, 88, 111 and detection of limits of 2.0, 3.8, 1.0 ng/ml for DEP, DEHP and DCP in 10-ml water sample, respectively. The proposed method was successfully applied to the determination of trace amount of phathalate esters in effluent water of the wastewater treatment plant and the lixivium of plastic fragments.

Intraspecific differences in effects of co-contamination of cadmium and arsenate on early seedling growth and metal uptake by wheat

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium （Cd） （0-10 mg/L） and arsenate （As（V）） （0-8 mg/L） on the growth parameters and accumulation of Cd and As in six wheat varieties Jing- 9428, Duokang- 1, Jingdong- 11, Jing-411, Jingdong-8 and Zhongrnai-8. The endpoints of wheat seedlings, including seed germination, biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties （p 〈 0.05）. The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongrnai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongrnai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.

Ecotoxicological effects of mixed pollutants resulted from e-wastes recycling and bioaccumulation of polybrominated diphenyl ethers in Chinese loach(Misgurnus anguillicaudatus)

To understand potential ecotoxicological effects of electrical and electronic equipment waste （e-waste） recycling and polybrominated diphenyl ethers （PBDEs） bioaccumulation in loaches, a semi-field experiment using Chinese loach （Misgurnus anguiUicaudatus） as experimental fish was performed. Larval loaches were kept in net-cage for three months in an e-wastes recycling site and a reference site in Southeastern China. There was significant difference of the survival rate between the loaches from the e-wastes recycling site （27%, 19/70） and from reference site （70%, 49/70）. Histopathological responses were also found in all the livers examined in loaches from the e-wastes recycling site. These results showed that mixed pollutants resulted from e-wastes recycling led to ecotoxicological effects on loaches. The bioaccumulation of polybrominated diphenyl ethers （PBDEs）, the main pollutants in e-waste, in loaches was also studied, the mean concentration of total PBDEs in sediment was 6726.17 ng/g wet weight and in water samples was 4.08 ng/L （dissolved phase）. BDE 209 was the dominant congener in sediment and with relatively high concentration in water. Relatively low concentration of BDE 209 （less than 0.01% of total PBDEs） and high concentration of BDE47 （up to 39.34% of total PBDEs） were detected in loaches.

Combination of biodiesel-ethanol-diesel fuel blend and SCR catalyst assembly to reduce emissions from a heavy-duty diesel engine

In this study, the efforts to reduce NOx and particulate matter （PM） emissions from a diesel engine using both ethanol-selective catalytic reduction （SCR） of NOx over an Ag/Al2O3 catalyst and a biodiesel-ethanol-diesel fuel blend （BE-diesel） on an engine bench test are discussed. Compared with diesel fuel, use of BE-diesel increased PM emissions by 14% due to the increase in the soluble organic fraction （SOF） of PM, but it greatly reduced the Bosch smoke number by 60%-80% according to the results from 13-mode test of European Stationary Cycle （ESC） test. The SCR catalyst was effective in NOx reduction by ethanol, and the NOx conversion was approximately 73%. Total hydrocarbons （THC） and CO emissions increased significantly during the SCR of NOx process. Two diesel oxidation catalyst （DOC） assemblies were used after Ag/Al2O3 converter to remove CO and HC. Different oxidation catalyst showed opposite effect on PM emission. The PM composition analysis revealed that the net effect of oxidation catalyst on total PM was an integrative effect on SOF reduction and sulfate formation of PM. The engine bench test results indicated that the combination of BE-diesel and a SCR catalyst assembly could provide benefits for NOx and PM emissions control even without using diesel particle filters （DPFs）.

Study on superoxide and hydroxyl radicals generated in indirect electrochemical oxidation by chemiluminescence and UV-Visible spectra

The generation and transformation of radicals on the cathode of indirect electrochemical oxidation were studied by chemilumines- cence(CL)and UV-Visible spectra in the reactor with a salt bridge that connected the separated chambers.The CL intensity of 4×10^(-9)mol/L luminol on the cathode with bubbling oxygen was about seven times that of the intensity without it,which was because of the generation of reactive oxygen species(ROS).The existence of ROS,especially the generation of the superoxide radical,coul...

Aging effect on the mobility and bioavailability of copper in soil

Aging effect on the mobility and bioavallability of copper （Cu） was investigated using a spiked soil with different incubation periods from 3 to 56 d. Wheat was planted and earthworms were cultured separately in the incubated soils. The mobility of Cu in soil was evaluated by a chemical fractionation scheme and the toxicity and bioavailability were assessed by measuring the biomass and Cu concentration in tissues. Results showed that aging had a significant effect on Cu fraction distribution, of which Cu tended to incorporate from the exchangeable into more stable fractions such as the reducible and oxidisable fractions. However, aging had little effect on Cu bioavailability to wheat and earthworm. Comparing the soil being incubated for 3 d and 56 d, Cu concentration in wheat roots decreased from 14.5 to 12.8 mg/kg, and no significant changes in Cu concentration were observed in both wheat shoots and earthworms. The Cu concentration was around 2.0 and 50 mg/kg for wheat shoots and earthworms, respectively, irrespective of soil incubation time. The CaC12-extractable Cu had a linear relationship with Cu concentration in wheat roots （R2 = 0.65, P 〈 0.05）, but no linear relationship can be found for wheat shoots and earthworms. Biological control may be more crucial for Cu accumulation in organism than the changes in soil Cu fraction caused by aging.

The acute lethality and endocrine effect of 1,2,3,7,8-PeCDD in juvenile goldfish (Carassius auratus) in vivo

1,2,3,7,8-PeCDD was administrated to juvenile goldfish （Carassius auratus） by peritoneal injections to explore the acute lethality and endocrine effects of 1,2,3,7,8-PeCDD in vivo. The value of acute median lethal dosage （LD50） of 1,2,3,7,8-PeCDD was determined in acute lethality tests. The endocrine effect of 1,2,3,7,8-PeCDD, whose exposed concentrations were determined based on the LD50 （1.84 mg/kg）, was studied by measuring the plasma vitellogenin （Vtg） content in juvenile male goldfish with enzyme-linked immunosorbent assays （ELISA）. Due to its significant induction of the plasma Vtg after one week＇s exposure in vivo in the 1/2 LD50 and LD30 groups, 1,2,3,7,8-PeCDD might be one of the important contributors to the estrogenic effect of PCDDs in the environment. The values of 1/2 LD50 and LD30 were within the range of the effective dosages of 1,2,3,7,8-PeCDD, indicating that there was a certain relationship between the estrogenic effective dosages and the LD50.

Use of QSAR and SSD methods on deriving predicted no-effect concentrations in seawater and sediment for ten individual parent-and alkyl-PAHs and a case study on the assessment of their ecological risks from the Dalian Bay, China

Parent and alkylated polycyclic aromatic hydrocarbons(alkyl-PAHs),which are a class of important toxic components of crude oil especially in the marine environment,exhibit adverse effects on aquatic life and potentially pose a human health risk.However,the lack of chronic toxicity data is one of the hindrances for alkylPAHs when assessing their ecological risks.In this study,predicted no-effect concentrations(PNECs)in seawater and marine sediment for ten parent-and alkyl-PAHs were derived by applying species sensitivity distributions(SSDs)and quantitative structure-activity relationships(QSARs).The local area,Dalian Bay,where an oil-spilled accident happened in 2010,was chosen as a case site to assess ecological risks for ten PAHs in surface seawaters and marine sediments.Their PNECs in seawater and sediment for protecting aquatic organisms in marine ecosystems were calculated and recommended in the range of 0.012-2.79μg/L and 48.2-1337 ng/g(dry weight),respectively.Overall,the derived PNECs for the studied PAHs in seawater and marine sediment were comparable to those obtained by classical methods.Risk quotient results indicate low ecological risks to ecosystems for ten parent-and alkyl-PAHs in surface seawaters and surface sediments from the Dalian Bay.These findings provide a first insight into the PNECs and ecological risks of alkyl-PAHs,emphasizing the role of the computational toxicology in ecological risk assessments.The use of QSARs has been identified as a valuable tool for preliminarily assessing ecological risks of emerging pollutants,being more predictable of real exposure scenarios for risk assessment purposes.

A novel fiber coating for solid phase microextraction and its application for the extraction of n-alkane from aqueous sample

Base on the previous work in laboratory, a novel polyaniline doped with polydimethylsiloxane coating was developed on a stainless steel wire for solid phase microextraction（SPME） by electroplating method. This electroplating method not only has advantages of ease preparation and simple equipments required, but also increases the lifetime of the SPME fiber. The composite fiber（polyaniline/ polydimethylsiloxane（PANI/PDMS）） was evaluated by analyzing n-tridecane, n-tetradecane and n-pentadecane in aqueous sample. The new fiber coating showed comprehensive abilities to extract alkanes compounds. The relative standard deviations were found to be 6.8%-10.33%.

On-line enrichment and determination of polycyclic aromatic hydrocarbons in atmospheric particulates using high performance liquid chromatography with fluorescence as detector

Seven polycyclic aromatic hydrocarbons （PAHs） in atmospheric particulates were determinated by high performance liquid chromatography （HPLC） with fluorescence detector using direction injection and an on-line enrichment trap column. The method simplified the sample pretreatment, saved time and increased the efficiency. With the on-line trap column, PAHs were separated availably even underground injecting 1.0 ml sample with relatively high column efficiency. The recoveries of the seven PAHs were from 85% to 120% for spiked atmospheric particulate sample. The limit of detection was 15.3-39.6 ng/L （S/N=3.3）. There were good linear correlations between the peak areas and concentrations of the seven kinds of PAHs in the range of 1-50 ng/ml with the correlation coefficients over 0.9970. Furthermore, it also indicated that the method is available to determine PAHs in atmospheric particulates well.

Bioavailability of cyanide in the different environmental compartments

Vascular plants possess an enzyme system that detoxifies cyanide by converting it to the amino acid asparagine. Hybrid willows （Salix matsudana Koidz×Salix alba L.） were exposed to cyanide to determine whether willows can transport and metabolize this compound. Pre-rooted trees were grown in different environmental compartments, spiked or irrigated with potassium cyanide at 24.0±0.5℃. Cyanide in compartments, in air and in tissues of plants was analyzed spectrophotometrically. Results from this study indicated that large amounts of applied cyanide was removed from the systems during the presence of willows. Growing compartments of plants have a strong influence on the removal rates of cyanide. Little or no initial cyanide was detected in plant materials. Volatilization of cyanide was not occurring. Mass balance studies showed that applied cyanide was significantly metabolized during transport through willows cuttings. However, there was a clear difference between the metabolism rates of cyanide by willows exposed to different environmental compartments. The highest cyanide metabolism rate was found at the treatment with willows growing in hydroponic solution with a metabolism rate of 2.44 mgCN/（kg, d）, followed by willows growing in sand with a value of 1.02 mgCN/（kg·d）. The lowest metabolism rate had the willows growing in soils（0.43 mgCN/（kg·d）. In conclusion, transport and metabolism of cyanide in plants is likely and phytoremediation of cyanide is a feasible option for cleaning soils and water contaminated with cyanide.

Lead and Cadmium Adsorption onto Iron Oxides and Manganese Oxides in the Natural Surface Coatings Collected on Natural Substances in the Songhua River of China

Natural surface coatings collected from natural substances （NSCsNS） were employed to study the roles of the main chemical components （iron oxides, manganese oxides, and other components） in controlling the adsorption of lead（Pb） and cadmium（Cd） in aquatic environments. The selective chemical extraction followed by the adsorption of Pb and Cd experiments and statistical analysis, were used to investigate the adsorption property of each component. Hydroxylamine hydrochloride was used to remove manganese oxides selectively, and sodium dithionite was used to extract iron oxides and manganese oxides. The result indicated that iron oxides and manganese oxides played an important role in the adsorption of Pb and Cd on NSCsNS, and the relative contribution was about two-thirds. The contribution of manganese oxides was the greatest, with a lesser role indicated for other components. The adsorption ability of manganese oxides for Pb and Cd was greater than that of iron oxides or other components for Pb and Cd. The Pb adsorption observed in each component was greater than Cd adsorption.

Improved preparation and identification of aristolochic acid-DNA adducts by solid-phase extraction with liquid chromatography-tandem mass spectrometry

Aristolochic acid （AA） is a known nephrotoxin and potential carcinogen, which can form covalent DNA adducts after metabolic activation in vivo and in vitro. A simple method for preparation and characterization of aristolochic acid-DNA adducts was developed. Four AA-adducts were synthesized by a direct reaction of AAI/AAII with 2′-deoxynucleosides. The reaction mixture was first cleaned-up and pre-concentrated using solid phase extraction （SPE）, and further purified by a reversed-phase high performance liquid chromatography （HPLC）. By the application of developed SPE procedure, matrices and byproducts in reaction mixture could be greatly reduced and adducts of high purity （more than 94% as indicated by HPLC） were obtained. The purified AA-DNA adducts were identified and characterized with liquid-electrospray ionization-quadrupole-time of flight-mass spectrometry （LC-ESI-Q-TOF-MS/MS） and LC-Diode array detector-fluorescence （LC-DAD-FL） analysis. This work provides a robust tool for possible large-scale preparation of AA-DNA adduct standards, which can promote the further studies on carcinogenic and mutagenic mechanism of aristolochic acids.

Synthesis and Crystal Structure of (1R,2S,3S,4S)-(6-O-Acetyl-1,2-O-isoproplidene-3,5-dideoxy-α-D-glucofuranoso)-1,3,5-trihydro-2,3-oxathiaindene-2,2-dioxide

（1R,2S,3S,4S）-（6-O-Acetyl-1,2-O-isoproplidene-3,5-dideoxy-α-D-glucofuranoso）-1,3,5-trihydro-2,3-oxathiaindene-2,2-dioxide（C11H16O8S,Mr=308.30） was synthesized and structurally characterized by NMR,MS and single-crystal X-ray diffraction.It belongs to the triclinic system,space group P1 with a=7.0836（14）,b=10.832（2）,c=14.895（3）,α=96.01（3）,β=98.85（3）,γ=108.59（3）o,V=1055.8（4）3,Z=3,Dc=1.455g/cm3,F（000）=486,μ=0.264mm-1,the final R=0.0360 and wR=0.0712.It is a tricyclic sultone derivative composed of three five-membered rings.

Evaluating the effectiveness of using ClO_2 bleaching as substitution of traditional Cl_2 on PCDD/F reduction in a non-wood pulp and paper mill using reeds as raw materials

The effectiveness of ClO_2 bleaching as a replacement for conventional Cl_2 bleaching,which is intensively practiced in developing countries,to reduce polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs)in non-wood pulp and paper mills has not been field tested.The first field study was performed to investigate PCDD/F variations when ClO_2 bleaching was used as a substitute for conventional Cl_2 bleaching in a non-wood pulp and paper mill.It was found that the PCDD/F toxic equivalents(TEQs)in solid and effluent samples were approximately 1.3–14.9 times lower when ClO_2 bleaching was used instead of the conventional Cl_2 bleaching.2,3,7,8-Substituted tetrachlorinated dibenzofurans(2,3,7,8-TCDF)were the dominant contributors to total PCDD/F TEQs in samples from the investigated mill when using conventional Cl_2 bleaching.The formation amounts of 2,3,7,8-TCDF were reduced from 1.56–2.76 pg TEQ/g to 0.02–0.32 pg TEQ/g in solid samples when ClO_2 bleaching was used instead of the conventional Cl_2 bleaching.The replacement of Cl_2 with ClO_2 might decrease the chlorination reactions of dibenzofuran as potential precursors,and thus reduce the formation amounts of 2,3,7,8-TCDF.The results could provide important knowledge for suggesting the best available technique for PCDD/F reduction for non-wood pulp and paper mills in developing countries.

Gas-particle partitioning of polychlorinated dibenzo-p-dioxins and dibenzofurans in the sintering process

The distribution of seventeen gaseous and particle-bound 2,3,7,8-substituted chlorinated PCDD/Fs in the flue gas of different windboxes of the sintering machine was analyzed. The influence of temperature change on the PCDD/Fs emission from the sintering process and the formation mechanism of PCDD/Fs were discussed. The result has shown that among the seventeen gaseous and particle-bound PCDD/Fs in the flue gas of different windboxes, furans occupied the major place. The proportion of the gaseous PCDD/Fs in most windboxes is from 40% to 60%. The change tendencies of the concentration of both the gaseous and particle-bound PCDD/Fs were similar, with a higher level at the end of the sintering bed. The PCDD/Fs concentration＇ s change tendency in the windbox was very consistent with the change of temperature of the flue gas in the windboxes. More than 60% PCDD/Fs of the total PCDD/Fs emission amount was emitted at the end of the sintering bed. Only this part of the waste gas accounted for 12% of the total waste gas volume.

Understanding the Water Crisis in China:Towards a Harmonious Aquatic Environment

The water resources in China are much often regarded as insufficient and unevenly distributed. As a result of fast economic development and urbanization in recent years,serious water shortage,contamination and deterioration of aquatic ecosystem are arising. In order to establish a sustainable development,scientific utilization of water resources and protection of the aquatic environment are urgently needed in China.