Toxic Contaminants Research Articles

Health risk assessment of polycyclic aromatic hydrocarbons and heavy metals in surface water from Bakana river in southern Nigeria

The level of polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) in surface water from Bakana River located within the hydrocarbon pollution-prone Niger Delta Region of Nigeria was assessed to evaluate possible human health hazards and other associated risk to seafood. Surface water samples were analyzed for various physicochemical parameters using standard analytical methods. The level of sixteen (16) USEPA-recognized PAH compounds and selected HMs (Zn, Cu, Ni, Pb, Cr and Cd) were investigated. PAHs and HMs were determined using gas chromatography-flame ionization detector (GC-FID) and atomic absorption spectrophotometer (AAS). Analytical results revealed deterioration of surface water from the study location, with significantly (P<0.05) high turbidity (30.00 ± 0.63 NTU), BOD (8.06 ± 0.66mg/l), total hardness (1079.05 ± 10.11mg/l) and nitrite (4.98 ± 0.16mg/l). For HMs, Cd and Pb showed values above WHO permissible limits, recording 0.014±0.001mg/l and 0.132±0.001mg/l respectively. Varying levels of PAH compounds were found to be present in the surface water samples. Naphthalene, acenaphthylene acenaphthene, phenanthrene, fluoranthene and pyrene showed significance presence when values were compared with results for control surface water samples. Health risk evaluation was performed using Estimated Daily Intake (EDI), Target Hazard Quotient (THQ) and Carcinogenic Risk (CR) assessment, and indicated that surface water from Bakana River has potential health risk cancer risk for Cd, Pb, Cr and Ni in adult and children populations. These findings demonstrate that residents of Bakana Community and its environs are exposed to contaminated surface water and the health risks associated with consumption of toxic contaminants in water.

Toxic metal contamination in edible salts and its attributed human health risks: a systematic review and meta-analysis.

Sodium chloride, commonly referred to as table salt, is the most widely utilized seasoning in culinary applications. Nevertheless, the most of oral salts used contain impurities. Arsenic (As), mercury (Hg), cadmium (Cd), and lead (Pb) are the most common impurities found in salt. In this meta-analysis, we examined the status of Pb, Hg, Cd, and As in the salt sample consumed in Iran. For this purpose, a complete search was carried out in English (Scopus, PubMed, and Web of Science) and Persian (Scientific Information Database, IranMedex, and Magiran) electronic databases to identify related articles published by July 2024. In the present meta-analysis, twelve studies with a total number of 610 salt samples were included in the analyses. According to the findings, the pooled mean levels of Hg, Pb, As, and Cd were 0.06µg/g (95% CI: 0.04-0.08), 2.98µg/g (95% CI: 2.35-3.61), 0.42µg/g (95% CI: 0.19-0.66), and 0.71µg/g (95% CI: 0.76-1.04), respectively. The levels of Cd and Pb in rock salt are higher than those found in the sea and refined salt. The hazard index (HI) values were recorded as 0.41 (95% CI: 0.235 to 0.588) for men, 0.428 (95% CI: 0.246 to 0.614) for women, and 0.594 (95% CI: 0.341 to 0.853) for children. The results of the present study show higher levels of Pb and Cd in unrefined salt compared to refined salt. Additionally, the health risk associated with exposure to Cd, Pb, As, and Hg through salt consumption is negligible in Iranian adults.

Defect-engineered C,N-ZnO/Co3O4/CoFe2O4/Fe3O4 for ultra-fast tetracycline degradation and environmental impact assessment using an in silico mathematical model

A significant breakthrough has been achieved in the ultra-fast degradation of toxic contaminants in wastewater. Novel C, N co-doped ZnO/Co3O4/CoFe2O4/Fe3O4 quaternary oxide was engineered using a tri-metallic zeolitic imidazolate framework (Zn/Co/Fe-ZIF). The synthesized material degraded 85% tetracycline (TC) within just 15 s of visible light illumination (and achieved a total degradation of 90.9% in 6 min). The catalyst's remarkable performance was ascribed to the synergistic effect of dual S-scheme heterojunctions at the oxide's interface and the light-independent activation of H2O2 by the multivalent cationic sites (Co3+/Co2+ and Fe3+/Fe2+) on the catalyst. These two mechanisms not only reduced the TC degradation time to just a few seconds, but also unlocked the degradation potential of the catalyst in the absence of light (70% TC degradation was achieved under ambient dark conditions). XPS studies showed that the ZIF-mediated synthesis introduced double or triple oxygen vacancy sites and N substitutional defects, which enhanced the catalyst’s efficiency by increasing the production of reactive oxygen species on its surface. VB-XPS and UPS analysis were performed to correctly elucidate the charge transfer mechanism in the heterostructure. The results of EPR and LC–MS studies established that the synthesized heterostructure is capable of generating abundant reactive oxygen species which are responsible for the fragmentation of TC molecules within a short period of time. Furthermore, the toxicity profile of the generated degradation products was also assessed via an in silico approach. Interestingly, despite such a short degradation timeframe, the generated degradation products had lower toxicity than TC.

Metal Nanoparticles as Effective Adsorbents to Treat Mining Industry Wastewater

Water containing various toxic contaminants is one of the most severe problems throughout the world. Many technologies have been used to treat such water in the past few decades. Current technologies contain the process of ion exchange, electrochemical methods and flotation. The use of nanotechnology is gaining importance every day in this line. Aluminium titanium, silicon and iron oxides are gaining importance as iron oxide is the cheapest metal available in good quantity in nature which also has suitable magnetic a good property when compared to other oxides. Its properties can be exploited to remove heavy toxic metal pollutants from contaminated water. In the present work, nanoparticles of iron oxide were used to remove the Lead (Pb) (II) ions present in the mining industrial wastewater. The efficiency of adsorption was studied by the Freundlich mathematical model. The results show that the magnetite nanomaterial can be used effectively as a potent adsorbent material in Standard Temperature and Pressure (STP).

Effectiveness of artificially planted mangroves on remediation of metals released from ship-breaking activities.

The pervasive and escalating issue of toxic metal pollution has gathered global attention, necessitating the exploration of innovative ecological strategies like phytoremediation. This study explored the extent of potentially toxic metal contamination status and the effectiveness of three planted mangrove species (Avicennia marina, Bruguiera gymnorhiza,and Excoecaria agallocha) in phytoremediation efforts to reduce pollution level. The results indicated that the mean concentrations of elements in the sediment of the area followed a descending sequence: Fe (27,136.67±929.57mg/kg)>Ti (3371.53±228.08mg/kg)>Sr (198.59±37.43mg/kg)>Zr (159.49±22.35mg/kg)>Rb (159.11±17.63mg/kg)>Cu (82.73±5.01mg/kg)>Zn (61.29±2.42mg/kg). The comprehensive assessment of pollution indices, encompassing enrichment factor (EF), contamination factor (CF), pollution load index (PLI), and geo-accumulation index (Igeo), elucidated a low to medium contamination level, particularly regarding Cu, primarily attributed to anthropogenic sources. Correlation analysis and principal component analysis (PCA) unveiled the influence of anthropogenic activities on heavy metal distribution. Evaluating the phytoremediation potentiality via bioconcentration factor (BCF) and translocation factor (TF) revealed limited metal accumulation in plant tissues, yet TF values exceeding 1 demonstrated efficient metal translocation from roots to aerial parts. Remarkably, Excoecaria agallocha exhibited the greatest phytoremediation potential, effectively translocating metals such as Cu and Zn to aerial parts (TF>1). Thus, the intricate interplay between mangrove species and their environmental setting emerges as pivotal in curbing heavy metal transfer to neighboring estuarine and marine ecosystems.

Selection of High-Affinity and Selectivity AFB1 Circular Aptamer for Biosensor Application.

Detecting trace amounts of aflatoxin B1 (AFB1), one of the most toxic food contaminants, is crucial for efficiently preventing potential health risks. Circular aptamers are promising candidates for bioanalytical applications due to their enhanced biological and structural stability as well as their compatibility with rolling circle amplification (RCA). Herein, we employed a high-efficiency magnetic chain graphene oxide-based SELEX to generate circular aptamers that bind AFB1 with high affinity and selectivity. Notably, the selected circular aptamer, CAFB1-A-2, exhibited a significant sequence similarity to the classical AFB1 linear aptamer but demonstrated a distinct thermodynamic mechanism for binding. The binding of CAFB1-A-2 was driven by both enthalpy and entropy, whereas the classical linear aptamer exhibited a notable entropy loss that required a greater enthalpy compensation. Utilizing this circular aptamer, we developed a sensitive AFB1 detection system featuring an RCA-assisted allosteric DNAzyme biosensor with a detection limit (LOD) of 265 pM. Furthermore, the constructed aptasensor successfully detected AFB1 in spiked rice and corn, achieving LODs of 11 and 9 μg/kg, respectively, within approximately 4 h. This study provides a sensitive and reliable alternative to the development of an aptasensor for AFB1, holding great potential in the field of food safety detection.

Bio-green synthesis of bismuth oxide nanoparticles using almond gum for enhanced photocatalytic degradation of water pollutants and biocompatibility.

The discharge of dye-contaminated industrial wastewater is a significant source of water and soil pollution. The eco-friendly synthesis of multifunctional bismuth oxide nanoparticles (BiO-NPs) offers a promising approach for the removal of toxic contaminants. The incorporation of natural polymers in nanoparticle production has gained significant scientific attention due to their environmentally friendly and efficient properties. This study emphasizes the use of almond gum (ALG) as a potent bio-reductant for the green synthesis of BiO-NPs. The synthesized BiO NPs exhibited a surface area of 24.5774 m2/g, demonstrating their potential for enhanced catalytic activity. The photocatalytic activity of the BiO NPs was evaluated by degrading Congo Red and Brilliant Green dyes under visible light irradiation, achieving degradation efficiencies of 90.21 % ± 0.32 and 90.52 % ± 0.29, respectively. Radical trapping experiments confirmed the primary roles of photo-generated electrons and hydroxyl radicals in the degradation process. The reusability analysis demonstrated that the BiO-NPs could be effectively recycled for 4 cycles, maintaining good stability. Degradation intermediates were identified using LCMS. Additionally, the catalytic reduction conversion of 4-nitrophenol to 4-aminophenol using NaBH₄ achieved a degradation efficiency of 92 % ± 0.41 within 32 min. Biocompatibility assessments using NIH/3T3 cell lines indicated that ALG-BiO NPs are safe for environmental applications.

Polychlorinated naphthalenes (PCNs) and polychlorinated biphenyls (PCBs) in surface soils and street dusts in Detroit, Michigan.

Polychlorinated naphthalenes (PCNs) and polychlorinated biphenyls (PCBs) are toxic contaminants that were produced and used in large quantities for their stability, inertness, and other desirable electrical, cooling, and lubricating properties. Due to their environmental persistence and improper disposal, these contaminants have become broadly distributed in the environment. This study examines the levels, composition, distribution, and potential sources of these compounds in surface soils and street dusts collected at 19 residential and industrial areas in Detroit, Michigan. Each sample was analyzed for 32 PCN and 37 PCB congeners using gas chromatography/mass spectrometry. The geometric mean concentrations of total PCNs and total PCBs were 61 (range:11-1933) and 432 (range: 32-18,637) ng/g, respectively. The most common PCNs were tetra- to hexacongeners and PCN-59 was most prevalent individual congener. For PCBs, hexaPCBs were most common and PCB-158 was dominant. PCN and PCB levels in soils at most sites exceeded health-based guideline levels. Given the short half-lives of PCNs and restrictions on PCN and PCB production, our results imply ongoing or recent releases. Emission sources identified by principal components and other analyses include industrial thermal processes included fuel combustion and electrical waste handling at a scrap metal processor for PCNs and PCBs, respectively. The presence of sources and "hotspots" of these toxic "legacy" contaminants in urban settings like Detroit highlight the potential for human exposure and the need to identify and control sources to prevent further environmental dispersal, exposure and risk.

Evaluation of bromelia karatas as a bioindicator of lead contamination

Abstract: metals toxic contamination is a problem that has increased mainly due to anthropogenic activities. Lead (Pb) is a hightly toxic metal present in the environment due to industrial activities, such as mining, smelting, manufacturing, and burning of fossil fuels. This work studied Bromelia karatas as a bioindicator of the quality of the environment in the presence of lead. Forty 200-day-old plants (Bromelia karatas) were used, of which 30 were transplanted in a substrate (Peat moss) contaminated with Pb, using Pb(NO3)2 as a contaminating agent, at different concentrations, T1= 1000, T2=2000 and T3=3000 mg/kg (milligram of Pb/Kilogram of substrate), and 10 were used as control (Tc). At the end of the experiment, the presence of Pb was analyzed and found in the plant tissues (leaves and roots), using the ICP-OES equipment. This research revealed the potential of Bromelia karatas as a bioindicator of Pb contamination in soil, causing visible symptoms of foliar damage on its leaves with high doses of the contaminant. The low cost, easy reproduction and portability of bromeliad compared to other bioindicators make it a better option to be used as a bioindicator and/or biomonitor.

Immunochromatographic food control tools: New developments and practical prospects

In the modern food production technologies, the tools and means of simple and rapid testing raw materials, intermediate products and the final ready-to-consume food products are in high demand. This monitoring allows determining the content of toxic and pathogenic contaminants and confirms the compliance of the objects being tested with the established regulatory requirements. Mobile tests tools and means (so called test systems) provide the opportunity of wide range monitoring without involving the specialized laboratories and highly qualified specialists. Thus, test systems for detection of toxic and pathogenic contaminants serve as the useful addition to confirming instrumental analytical methods. An actively developing approach for this field testing is the using of immunochromatographic test strips, in which strips all the necessary reagents are applied to the membrane components of the analytical system. Contact of the test strip with the sample being tested, initiates all further interactions and generates the recordable or visually assessable optical signal. The market of test systems based on immunochromatographic analysis is constantly growing, thus offering the permanently widening choice of solutions. However, in recent years there has been a real boom of new developments in immunochromatography field, thus offering various options for highly sensitive and information capacitive analytical systems. This study systematizes these developments and provides their comparative assessment in terms of prospects for their technological implementation and practical application in the coming years. The opportunities of designing the antibodies and alternative receptor molecules for controlling the affinity and the selectivity of recognition of the compounds being monitored are considered. The advantages and limitations of the new nanodispersed markers and non-optical methods for their registration in immunochromatography are discussed. The methods for quantitative assessment of the contaminants content via immunochromatography are characterized. The developed design options of the test systems for multiplex control — simultaneous detection of several compounds — are presented. Examples of integration of immunochromatographic tests with the systems of automatic registration, processing, transfer, storage and analysis of results of numerous tests are represented.

Species Differences in the Biotransformation of Aflatoxin B1: Primary Determinants of Relative Carcinogenic Potency in Different Animal Species.

It has been known since the early days of the discovery of aflatoxin B1 (AFB1) that there were large species differences in susceptibility to AFB1. It was also evident early on that AFB1 itself was not toxic but required bioactivation to a reactive form. Over the past 60 years there have been thousands of studies to delineate the role of ~10 specific biotransformation pathways of AFB1, both phase I (oxidation, reduction) and phase II (hydrolysis, conjugation, secondary oxidations, and reductions of phase I metabolites). This review provides a historical context and substantive analysis of each of these pathways as contributors to species differences in AFB1 hepatoxicity and carcinogenicity. Since the discovery of AFB1 as the toxic contaminant in groundnut meal that led to Turkey X diseases in 1960, there have been over 15,000 publications related to aflatoxins, of which nearly 8000 have addressed the significance of biotransformation (metabolism, in the older literature) of AFB1. While it is impossible to give justice to all of these studies, this review provides a historical perspective on the major discoveries related to species differences in the biotransformation of AFB1 and sets the stage for discussion of other papers in this Special Issue of the important role that AFB1 metabolites have played as biomarkers of exposure and effect in thousands of human studies on the toxic effects of aflatoxins. Dr. John Groopman has played a leading role in every step of the way-from initial laboratory studies on specific AFB1 metabolites to the application of molecular biomarkers in epidemiological studies associating dietary AFB1 exposure with liver cancer, and the design and conduct of chemoprevention clinical trials to reduce cancer risk from unavoidable aflatoxin exposures by alteration of specific AFB1 biotransformation pathways. This article is written in honor of Dr. Groopman's many contributions in this area.

Assessment of Potentially Toxic Elements Contamination in Water and Sediments from Vembanad Lake, Kerala, India: In Accounts with the Influence of its Major In Flow Rivers

Assessment of Potentially Toxic Elements Contamination in Water and Sediments from Vembanad Lake, Kerala, India: In Accounts with the Influence of its Major In Flow Rivers

Development of stable and porous Ag2O-loaded hydroxyapatite nanocomposites for enriched photocatalytic degradation of Rhodamine B under visible light.

A simple and inexpensive process from natural phosphate in the presence of Ag+ ions was used to develop Ag2O-loaded hydroxyapatite nanocomposites. The structural and textural characterization of the nanocomposites suggests that the Ag2O nanoparticles are well dispersed on the hydroxyapatite (HAp). The prepared nanocomposites show efficient Rhodamine B (RhB) dye photocatalytic degradation in water under visible and UV-visible light irradiation. Meanwhile, the photocorrosion instability and photosensitivity disadvantages of Ag2O could be largely solved when loaded into hydroxyapatite, which works as an electron sink receiving the electrons photogenerated by Ag2O and fixes the by-products onto the porous matrix. These composites demonstrate a practical potential for the remediation of toxic water contamination under various irradiation sources.

Treatment of Industrial Wastewater Using a Membrane Bioreactor Pilot Scale: A case Study of Industrial Wastewater From a Sisposal Pond in Phanomsarakham District, Chachoengsao, Thailand

This research studies the efficiency of industrial wastewater treatment using a membrane bioreactor (MBR). By using wastewater from wastewater disposal pond volumes of 300 liters and leachate volumes of 20 liters, aeration was fed continuously to provide the oxygen at an air flow rate of 150 l/min for 24 hours to activate the group of microorganisms. Then put the combined wastewater into the MBR. and then start the treatment system, collect each sample separately every 1 hour for a total of 12 hours, and sample in the 24th hour of the experiment. The result found that the amount of BOD, COD, SS, TP, and TOC contamination after MBR treatment has a continuous, statistically significant decrease in each hour of the experiment. The removal efficiencies of BOD were found to be 25%, 75%, and 68% (on 5th, 11th, and 12th hours), COD was found at 50.72% and 71.47% (on 5th and 12th hours), SS was found at 92% and 94% (on 6th and 12th hours), and TP was found at 84.72% and 73.70% (on 9th and 12th hour), respectively. and TOC was found at 47.07% (on 12th hours). The experimental results show that MBR is an effective treatment. can reduce the amount of contamination of organic and inorganic substances in wastewater to a statistically significant reduction. Can use a membrane biological reactor tank treatment system to apply wastewater treatment in the field. For use with wastewater with high toxic contamination, other elements and specific groups of microorganisms should be studied to be appropriate for the type of wastewater.

Ambient Toxic Air Contaminants in the Maternal Residential Area during Pregnancy and Cerebral Palsy in the Offspring.

Cerebral palsy (CP) is the most common permanent neuromotor disorder diagnosed in childhood. Although most cases have unknown etiology, emerging evidence suggests environmental risk factors of CP. We investigated whether ambient toxic air contaminants (TACs) in the maternal residential area during pregnancy, specifically volatile organic compounds (VOCs) and metals, were associated with offspring CP risk in California. We conducted a case-cohort study that included CP cases () and a 20% random sample of all live singleton births () who lived within a (8-km) radius of air toxics monitoring stations in California during 2005-2015 as the control comparison group. CP cases were ascertained from diagnostic records of the California Department of Developmental Services. We a priori selected TACs with suspected neurotoxicity and developmental toxicity, including 14 VOCs and 6 metals. We estimated the adjusted risk ratio (RR) and 95% confidence interval (CI) for CP and the average maternal residential exposures to each TAC over the entire pregnancy using modified Poisson regression. For air contaminant mixtures, we used quantile-based g-computation to estimate the effects of mixtures of VOCs or metals. Finally, we performed a negative control exposure analysis on exposure estimates of 36-48 months after delivery to evaluate uncontrolled confounding bias. Maternal residential exposures to six VOCs (benzene, toluene, 1,3-butadiene, acetone, acetonitrile, and methylene chloride) and four metals (antimony, lead, nickel, and vanadium) were associated with 3%-25% higher risk of CP per interquartile range increase, and the estimated mixture effects of VOCs (; 95% CI: 1.08, 1.43) or metals (; 95% CI: 1.20, 1.58) were stronger. The observed associations were close to null for negative control exposures (36-48 months after delivery) to mixtures of VOCs or metals and CP. In California, maternal prenatal residential exposure to VOCs and metals in the outdoor air, largely attributed to mobile traffic emission sources, was associated with an increased risk of CP in offspring. https://doi.org/10.1289/EHP14742.

Linking new national active biomonitoring data with stream macroinvertebrate communities suggests large-scale effects of toxic contamination on freshwater ecosystems.

Since recent years, an increasingly large number of toxic chemicals enters watercourses threatening freshwater biodiversity. But ecological studies still poorly document the quantitative patterns linking exposure to complex mixture of toxic chemicals and species communities' integrity in the field. In this context, French monitoring authorities have recently deployed at a national scale in situ biotests using the feeding inhibition of the crustacean Gammarus as toxicity indicator. In this paper, we conjointly exploit this new type of biomonitoring dataset and ecological data for macroinvertebrates to gain information about the structuring influence of toxicity on aquatic communities. Especially, we used multivariate analyses with variation partitioning for testing the hypothesis that toxicity (feeding inhibition index) can explain variations in the taxonomical composition between 76 stations on French streams while, for different spatial scales, estimating the confounding influences of other environmental and spatial factors. Our results showed that changes in the toxicity indicator were significantly associated with specific changes in the taxonomic composition of stream macroinvertebrate communities. That association was weakly confounded with the effects of environmental and spatial factors, especially at the largest spatial scale considered. That taxon turnover linked to toxicity was associated with reduced richness at the community scale, and the replacement of native taxa by alien taxa. Overall, our study thus supports the hypothesis that toxic contamination modifies the structure of stream communities and ergo threatens aquatic biodiversity.

Transformative knowledge of polar polycyclic aromatic hydrocarbons via high-resolution mass spectrometry.

Polycyclic aromatic hydrocarbons (PAHs) are toxic contaminants with a widespread presence in diverse environmental contexts. Transformation processes of PAHs via degradation and biotransformation have parallels in humans, animals, plants, fungi, and bacteria. Mapping the transformation products of PAHs is therefore crucial for assessing their toxicological impact and developing effective monitoring strategies. The present research aimed to explore the PAH detoxification products formed by the marine fish Atlantic haddock (Melanogrammus aeglefinus) after single PAH treatments. Using target and suspect screening analyses on an ion mobility quadrupole time-of-flight mass spectrometer (IM-QTOF MS), deprotonated compounds were identified and archived into a metabolite mass spectral library, which is systematized and presented in this work. The results offer an exclusive overview of the transformation products and their associated mass spectral features. Transformation products include hydroxy compounds, dihydrodiols, polycyclic aromatic acids, glucuronides, sulfates, glutathiones, cysteinylglycines, cysteines, and mercapturic acids. By documenting high-resolution mass spectrometry data, this comprehensive characterization provides a valuable reference point for the development of broad-spectrum analytical methods. It also addresses a critical gap in the field by presenting tentative identifications of PAH transformation products in the absence of analytical standards. Moreover, it encourages further investigation of these compounds as they have important toxicological relevance in both ecotoxicology and human research.

Discovery of phloridzin as a new antagonist for Di(2-ethylhexyl) phthalate-induced male reproductive toxicity based on the adverse outcome pathway network and drug-target gene set enrichment analysis.

Di(2-ethylhexyl) phthalate (DEHP) is a widespread ubiquitous phthalate environmental contaminant. The male reproductive toxicity (MRT) from exposure to DEHP and its main metabolite, mono(2-ethylhexyl) phthalate (MEHP), has been well documented. Fully elucidating its toxic mechanism and discovering effective antagonists are desirable means to reduce the health risks of DEHP. In this study, 552 genes related to MRT induced by DEHP/MEHP were screened out from the Comparative Toxicogenomics Database (CTD) and DisGeNET database. Next, we developed a global adverse outcome pathway (AOP) network based on the existed AOP-wiki. After functional enrichment analyses and mapping to the global AOP network, we found that the increased ROS level, cell cycle arrest, and increased apoptosis are key events (KEs) involved in DEHP-mediated MRT, which was validated in TM3 Leydig cell model. Among them, cellular apoptosis is the core KE in DEHP-induced MRT via network topological analysis. Eventually, we developed a novel in silico antagonist screening platform (http://43.136.69.224:3838/wlab/) based on drug-target gene set enrichment analysis (dtGSEA version 2.0). Several potential candidates that mitigate DEHP-mediated cellular apoptosis have been screened out, including quercetin, taurine, methionine, and phloridzin. Further experimental results demonstrated that phloridzin provided the most effective protection against MEHP-induced apoptosis in TM3 cells probably through the p53 and MAPK signaling pathways. Molecular docking and molecular dynamics simulations suggest that STAT3 and RUNX1 may be important targets for phloridzin to antagonize MEHP-induced MRT. Our study provides a new approach to discover the antagonists for the toxicity of environmental contaminants based on AOP network and dtGSEA methods.

Assessment of Toxic Metal Contamination in Coastal Sediments of Major Fishing Ports in the Southeastern Black Sea, Türkiye: Spatial Distribution, Risk Evaluation, and Source Identification

Assessment of Toxic Metal Contamination in Coastal Sediments of Major Fishing Ports in the Southeastern Black Sea, Türkiye: Spatial Distribution, Risk Evaluation, and Source Identification

Insight into migration of Cr(VI) in self-hardening slurry materials for trench cutoff wall.

The migration and immobilization of heavy metals in soil and groundwater pose significant environmental challenges, particularly in the context of Cr(VI), a highly toxic and mobile contaminant. Self-hardening slurry materials, commonly used for trench cutoff walls, have gained great attention due to their potential for pollutant containment. However, the relationship between their adsorption properties and pollutant diffusion behaviors remains poorly understood. This study investigates the adsorption properties and free-diffusion behaviors of Cr(VI) in two self-hardening slurry materials, SCB (slag-cement-bentonite) and MASB (MgO activated slag-bentonite), to better understand the pollutant migration and immobilization mechanisms. Adsorption experiments reveal that MASB exhibits a higher Cr(VI) adsorption capacity than SCB, resulting in greater retardation factors and longer breakthrough times, improved by 57.6% and 94.9% at Cr(VI) concentrations of 2600mg/L and 26000mg/L, respectively. However, free-diffusion tests show that MASB has a larger migration depth and shorter breakthrough times, reduced by 68.2% and 57.9%. Microscopic analysis reveals that the presence of stable and ion-exchangeable hydration products (hydrotalcite-like phases) in MASB enhances its Cr(VI) adsorption capacity but provides favorable conditions for Cr(VI) diffusion. SCB demonstrates superior retardation to Cr(VI) in free-diffusion due to the transformation of AFm phases absorbed with Cr(VI) into stable AFt phases.