Environmental Contamination Research Articles

Investigating multiple vegetable oils and recycled variant for microplastics extraction from water, integrated with Raman spectroscopy

The global production and disposal of plastics have led to pervasive contamination of natural environments, representing considerable risks to human health and ecosystems. This study introduces a novel oil-based method for extracting microplastics (MPs) from water samples, with a focus on optimizing extraction conditions and improving the quality of MPs identification using Raman spectroscopy. Various parameters including the type of oil, salinity, temperature, air incorporation, and washing solvent were investigated to enhance extraction efficiency and spectroscopic identification accuracy. Sunflower oil emerged as the preferred extraction medium due to its compatibility with Raman spectroscopy, offering high recovery efficiencies for polypropylene (PP) and polystyrene (PS). Additionally, ethanol was identified as a better washing solvent compared to hexane, improving MPs identification. The optimised method was then applied to environmental water samples, revealing matrix effects and challenges with digestion step. Despite these challenges, the proposed method represents a significant advancement in microplastic analysis, offering reliable detection and quantification in aquatic environments. Further optimisation is needed to address matrix effects and improve recovery efficiency, especially for smaller microplastics.

Pesticides and Heavy Metal Toxicity in Fish and Possible Remediation – A Review

Abstract Pesticides and heavy metals are considered as potent contaminants in aquatic environment. Both contaminants are sourced into the aquatic ecosystems by various types of anthropogenic as well as natural practices. Such types of aquatic contamination drastically affect the normal activity of associated living organisms particularly fish. Both the pesticides and heavy metals toxicity cause several negative effects on fish growth, physiology, immune response, reproduction, embryonic and larval development as well as different histopathology of major organs including fish gill, kidney, liver, gonads, and intestine. Besides, the consumption of contaminated fish poses a serious health concern to associated consumers. Considering these serious issues, the current review is designed to investigate the toxic effects of pesticides and heavy metals on different aspects of fishes along with their possible sources, major types, and mode of action as well as role of medicinal herbs to mitigate their toxicity.

Photochemical Transformation of Ibuprofen and Chlorophene Induced by Dissolved Organic Matter.

Both ibuprofen (IBP) and chlorophene (CP) are frequently detected contaminants in surface aqueous environment. Dissolved organic matter (DOM) is an important component in water with high photo-reactivity, playing an important role in the transformation processes of various organic pollutants. This study systematically studied the influence of DOM on the photochemical transformation of IBP and CP by using humic acid as model DOM. In addition, the effect of inorganic salts on this process is also considered due to the high salt content in the ocean. Further quenching experiments and reactive oxygen species (ROSs) detection were also conducted to explore the reactive species acting on the IBP and CP transformation. Based on the products analysis and theoretical calculation, we proposed the IBP and CP transformation mechanism. Overall, this study provides some new insights into the transformation of organic pollutants in natural surface water, which is significant for assessing the fate of pollutants.

Lack of effects of polystyrene micro- and nanoplastics on activity and expression of human drug transporters

Micro- and nanoplastics (MPs/NPs) constitute emerging and widely-distributed environmental contaminants to which humans are highly exposed. They possibly represent a threat for human health. In order to identify cellular/molecular targets for these plastic particles, we have analysed the effects of exposure to manufactured polystyrene (PS) MPs and NPs on in vitro activity and expression of human membrane drug transporters, known to interact with chemical pollutants. PS MPs and NPs, used at various concentrations (1, 10 or 100µg/mL), failed to inhibit efflux activities of the ATP-binding cassette (ABC) transporters P-glycoprotein, MRPs and BCRP in ABC transporter-expressing cells. Furthermore, PS particles did not impair the transport of P-glycoprotein or BCRP substrates across intestinal Caco-2 cell monolayers. Uptake activities of solute carriers (SLCs) such as OCT1 and OCT2 (handling organic cations) or OATP1B1, OATP1B3, OATP2B1, OAT1 and OAT3 (handling organic anions) were additionally not altered by PS MPs/NPs in HEK-293 cells overexpressing these SLCs. mRNA expression of ABC transporters and of the SLCs OCT1 and OATP2B1 in Caco-2 cells and human hepatic HepaRG cells were finally not impaired by a 48-h exposure to MPs/NPs. Altogether, these data indicate that human drug transporters are unlikely to be direct and univocal targets for synthetic PS MPs/NPs.

RNA methyltransferase NSUN2-mediated m5C methylation promotes Cr(VI)-induced malignant transformation and lung cancer by accelerating metabolism reprogramming

Hexavalent chromium [Cr(VI)], one common environmental contaminant, has long been recognized as a carcinogen associated with lung cancer, but roles and mechanisms of Cr(VI)-induced epigenetic dysregulations in carcinogenesis remain to be investigated. In this study, we identified that RNA m5C methyltransferase NSUN2 was significantly upregulated in Cr(VI)-transformed cells and lung tissues of Cr(VI)-exposed mice. Inhibition of NSUN2 reduced cell proliferation, migration, colony formation and tube formation abilities. We found NSUN2-mediated m5C modification induced metabolic reprogramming and cell cycle by promoting the mRNA stabilities of ME1, GLUT3 and CDK2. In addition, knockdown of NSUN2 attenuated tumorigenesis and angiogenesis in vivo. RNA m5C reader ALYREF was identified to be involved in NSUN2-mediated m5C modification in Cr (VI)-induced carcinogenesis. Further study showed that EP300 induced NSUN2 upregulation through transcriptional activation by inducing histone modification at H3K27ac site for regulating Cr(VI) carcinogenesis. Our findings demonstrated novel role and mechanism of NSUN2 and epigenetic changes by increasing the RNA m5C modification that are important for Cr (VI)-induced carcinogenesis through NSUN2/ALYREF pathway. NSUN2, ALYREF, ME1, GLUT3 or/and CDK2 may be used as potential new biomarkers or/and therapeutic target(s) in the future.

Nonylphenol displays immunotoxicity by triggering hemocyte extracellular traps in Manila clam via ROS burst, ERK pathway and glycolysis

Nonylphenol (NP), an endocrine disruptor, has been demonstrated to be a harmful environmental contaminant and toxic to organisms. In this study, to address concerns regarding the immunotoxicity of NP, we treated clam Ruditapes philippinarum hemocytes with NP in vitro and explored the underlying mechanisms of NP-induced extracellular traps (ETs). NP could induce the formation of hemocytes ETs in a dose-dependent manner. Transcriptomics analysis revealed changes of signaling pathway involved in immunity and energy metabolism in hemocytes after NP stimulation. In this process, both reactive oxygen species (ROS) and myeloperoxidase (MPO) were up-regulated. Moreover, mitogen-activated protein kinase (MAPK) signaling pathway was proved to be activated in the formation of NP-induced ETs, manifested as enhanced phosphorylation of extracellular signal-regulated kinase (ERK) but not p38 or c-Jun N-terminal kinase (JNK). In the presence of U0126, an ERK phosphorylation inhibitor, the NP-induced expression of NADPH oxidase enzyme (NOX) was significantly decreased, which further alleviated the ROS production and ultimately limited the release of ETs. NP exposure increased glucose uptake, along with enhanced activities of glycolysis-related enzymes such as hexokinase (HK) and pyruvate kinase (PK). After inhibiting glycolysis by the inhibitor 2-DG, the formation of NP-induced ETs was significantly suppressed. ERK could regulate mTOR signaling and the PI3K/AKT pathway, potentially directing ETs formation by orchestrating the glycolysis through the activation of key transcription factors c-Myc and HIF-1α. Collectively, the results preliminary confirm that the ERK-NOX-ROS axis and glycolysis are involved in NP-induced ETs formation, contributing to the cellular immunotoxicity in clam.

A Review of Pathogen Removal from Municipal Wastewater using Advanced Oxidation Processes: Agricultural Application, Regrowth Risks, and New Perspectives

Pathogen removal in wastewater offers a chance to recover water and nutrients for crop production, reducing environmental contamination and public health risks. However, the risk of pathogens regrowing in treated effluents can endanger public health if reused in agriculture, attracting stringent reuse standards. While advanced oxidation processes (AOPs) promise to reduce pathogens, eliminating regrowth potential in AOP-treated effluents requires further scrutiny. This review aimed to summarize the available evidence on understanding pathogen reduction and regrowth potential in AOP-treated effluents, following best practices for scoping reviews like the preferred reporting items for systematic reviews and meta-analysis (PRISMA). It covers recent pathogen studies under AOPs, current AOP investigations, the impact of AOP dosage and retention time on pathogen control, and challenges in reusing AOP-treated effluents for crop production. Additionally, it identifies areas needing improvement or complementary treatments for pathogen-free effluents with no regrowth potential. The review concludes by summarizing key findings and suggesting research areas for further exploration.

Bionic modified atmosphere film Inspired by plant stomata with curcumin as controllable gas “Switches” for fruit preservation

Modified atmosphere packaging (MAP) is a promising preservation technology for the fruits with the characteristics of respiration metabolism. However, traditional MAP cannot precisely control and regulate the selective permeation of gas. Inspired by the fact that plants control respiration through leaf stomata, we innovatively construct a bionic intelligent MAP of curcumin-porous starch/chitosan (Cur-PS/CS) with leaf stomata structure. Herein, PS is used as the bionic stomata, and Cur is used as the gas switch controlled by changing the pH and temperature. As a result, the CO2/O2 selectivity values are precisely controlled from 2.60 to 5.51 by controlling the amount of Cur released from PS. In which, the 10.3 % Cur-PS/CS displays the highest CO2/O2 selectivity value (5.51). In addition to outstanding tensile strength (51.54 MPa) and antioxidant activity (91.03 %), the inhibition zone diameters of 10.3 % Cur-PS/CS film against Escherichia coli, Staphylococcus aureus and Aspergillus niger reach 8 mm, 7.8 mm and 9.1 mm, respectively. Therefore, the 10.3 % Cur-PS/CS film effectively extends the shelf life of the non-climacteric fruit (cherries) and climacteric fruit (apple slices). More importantly it does not bring any issues with food safety and environmental contamination due to the excellent biodegradability of Cur-PS/CS film.

Effect of Cd2+ and Cu2+ on Desulfovibrio vulgaris strain ATCC 7757: Insights from sulfur isotope fractionation

Microbial sulfate reduction (MSR) is the predominant microbial metabolic process involved in sulfur cycling in metal-sulfide mining areas. In this study, we investigated the effect of Cd2+ and Cu2+ on MSR driven by Desulfovibrio vulgaris strain ATCC 7757, determined the corresponding sulfur isotope compositions to establish a fundamental relationship between toxicity and isotope fractionation. Cd2+ did not cause significant cellular irrecoverable damage until concentrations exceeded 3.5 ppm, and the bacteria would enhance the transfer of SO42- to APS to ensure the bacterial growth. The repair of DNA damage caused by Cd2+ was a gradually stimulated process, which resulted in a tolerance period. Cu2+ inhibited MSR in a dose-dependent manner at concentrations below 1 ppm, and the bacterial growth significantly inhibited. When exposed to 1 ppm Cu2+ for 48h, ATCC 7757 might enhance the substrates transport to maintain its culturability through up-regulating genes encoding H+-transporting ATPase, ABC transporters and Protein export. Cd2+ had minimal impact on δ34Ssulfate, with an enrichment factor (34ε) ranging from -11.7‰ to -12.3‰. Conversely, Cu2+ significantly affected the δ34Ssulfate (34ε = -11.1‰ to -15.4‰), resulting in a substantial decrease in δ34Ssulfide, with the lowest value of δ34Ssulfide recorded as -18.8‰ (-11.5‰ for control group). The study demonstrated that sulfur isotope fractionation could indicate different toxicity mechanisms of heavy metal on ATCC 7757, aiding in the identification of environmental contamination caused by heavy metals.

Using a conditioned place preference assay in fruit flies to examine effects of insecticidal compounds on contextual memory

Insecticides are vital for safeguarding agricultural crops against pests, albeit many lack selectivity towards pest species and are poorly bio-degradable. This leads to targeting of beneficial organisms like pollinators and widespread environmental contamination of soil and water. Exposure to insecticides such as neonicotinoids causes insect paralysis and mortality at higher doses, while sublethal doses can disrupt other functions that are crucial for survival such as learning and memory performance. Potent and selective arachnid venom peptides affecting a variety of molecular targets are being explored as bioinsecticide candidates. However, their effect on insect learning is poorly understood. We therefore established a sucrose-induced conditioned place preference (CPP) assay using Drosophila melanogaster fruit flies to provide a means of evaluating how various classes of insecticidal compounds interact with insect memory to assess their broader ecological consequences. Our results confirmed the adverse effect of a sublethal dose of the neonicotinoid insecticide imidacloprid (20 pg/fly) on fly CPP formation upon daily injection during the conditioning phase. However, imidacloprid did not affect CPP retrieval when applied after the conditioning phase. Sublethal doses of the two insecticidal spider venom peptides μ-DGTX-Dc1a (Dc1a; 70 pg/fly) and U1-AGTX-Ta1a (Ta1a; 125 pg/fly) had no effect on either CPP formation or retrieval, underlining their potential as novel and safe bioinsecticide candidates.

Development and fabrication of graphene oxide and reduced graphene oxide incorporated MnFe2O4@Bi2WO6 nanocomposite for efficient degradation of antibiotic drug as water contaminant under visible-light illumination

Tetracyclines are one category of extensively applied antibiotics. Meantime, owing to misapplication and inappropriate disposal, they are mostly discovered in wastewater, which causes a series of environmental contamination and stated a threat to a person's health and security. The present study investigates the photodegradation of tetracycline using MnFe2O4@Bi2WO6/graphene oxide, GO, and MnFe2O4@Bi2WO6/reduced graphene oxide, RGO, and MnFe2O4@Bi2WO6 nanocomposites as permanent photocatalyst with the aid of visible light. A facile microwave assisted combustion method was applied in solid state rapidly, conveniently to fabricate MnFe2O4@ Bi2WO6–GO and MnFe2O4@ Bi2WO6–rGO nanocomposites at low power 150 W and in time 10 min with very low amount of glycine (as fuel). Consequently, XRD, EDX Mapping, DRS, PL, TEM, FESEM, FTIR, VSM, BET and UV–Visible spectrophotometric analysis demonstrated characteristic of nanocomposites and specifications of existent photocatalyst. Magnetic investigations revealed that the MnFe2O4@ Bi2WO6-GO and MnFe2O4@ Bi2WO6–RGO nanocomposites can be easily separated from the solution by an external magnetic field. MnFe2O4@ Bi2WO6–GO nanocomposites were discovered with high specific surface area 73.83 m2/g than MnFe2O4@Bi2WO6–RGO nanocomposites with specific surface area 17.75 m2/g. Highest photocatalytic activity was determined for the MnFe2O4@ Bi2WO6–GO (catalyst-0.10 g/l, tetracycline antibiotic concentration 10 mg/l and at pH = 4) within 25 min of visible light irradiation without using any oxidizing agent. The investigation of kinetic study revealed that kinetic parameter specified to photodegradation and experimental outcomes follow first-order model. the superoxide, hydroxyl radicals, ℎ+ holes and light are the principal demonstrates of the reaction mechanism for the effective degradation of tetracycline drug. The evaluation of MnFe2O4@ Bi2WO6–GO and MnFe2O4@ Bi2WO6–RGO magnetic catalysts has proposed the encouraging and significant role of nanocomposites in perilous pharmaceuticals refinement from industrial wastewater and also, magnetically photocatalyst attributes can be used as a potent separable tool for eliminating water pollution problems in the various industry.

Regional BDE-209 emission, environmental fate and risks: Methods establishment, data filling and feature analysis

BDE-209 is an emerging environmental contaminant that poses a significant threat to human health. Despite its inclusion in the Stockholm Convention, the current regional emission levels, environmental fate, and corresponding risks remain unclear, especially with the ongoing release of BDE-209 during the disposal of waste electrical and electronic equipment. The significant gaps in BDE-209 emission data highlight the need for a regional approach to better understand these issues. Therefore, we established a method to identify regional BDE-209 emissions, environmental fate, and risks in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) using a substance flow analysis framework, fugacity model, and risk model. Our results showed: (1) Despite the increasing pressure of electronic waste, emissions have decreased with gradual strengthening of restrictions. The stage with the highest contribution to emissions is flame-retardant plastic production, which accounts for 41 % of emissions, followed by informal treatment (36 %). (2) The largest BDE-209 emissions are into air and soil, at 7.23 t and 4.56 t, respectively, and the highest reserves are in soil and sediment. (3) Infants and young children have the highest levels of exposure and cancer risk. This research helps fill the multi-regional data gap for BDE-209 and clarify the complex regional emission situation in the GBA.

Quantification Approaches in Non-Target LC/ESI/HRMS Analysis: An Interlaboratory Comparison.

Nontargeted screening (NTS) utilizing liquid chromatography electrospray ionization high-resolution mass spectrometry (LC/ESI/HRMS) is increasingly used to identify environmental contaminants. Major differences in the ionization efficiency of compounds in ESI/HRMS result in widely varying responses and complicate quantitative analysis. Despite an increasing number of methods for quantification without authentic standards in NTS, the approaches are evaluated on limited and diverse data sets with varying chemical coverage collected on different instruments, complicating an unbiased comparison. In this interlaboratory comparison, organized by the NORMAN Network, we evaluated the accuracy and performance variability of five quantification approaches across 41 NTS methods from 37 laboratories. Three approaches are based on surrogate standard quantification (parent-transformation product, structurally similar or close eluting) and two on predicted ionization efficiencies (RandFor-IE and MLR-IE). Shortly, HPLC grade water, tap water, and surface water spiked with 45 compounds at 2 concentration levels were analyzed together with 41 calibrants at 6 known concentrations by the laboratories using in-house NTS workflows. The accuracy of the approaches was evaluated by comparing the estimated and spiked concentrations across quantification approaches, instrumentation, and laboratories. The RandFor-IE approach performed best with a reported mean prediction error of 15× and over 83% of compounds quantified within 10× error. Despite different instrumentation and workflows, the performance was stable across laboratories and did not depend on the complexity of water matrices.

Neonicotinoids, Agriculture And Food Security Of Brazilian Honey: A Review

Pesticides used in agriculture have the function of controlling pests, diseases and preventing the development and growth of weeds, increasing the quality and productivity of crops. However, when they reach unwanted targets, such as bees, humans and other living beings, they cause harmful damage to ecosystems. Neonicotinoids, insecticides widely used in monocultures, such as soybeans and corn in Brazil, are especially harmful to bees, whether native or exotic, interfering with the foraging and pollination performance of plants. The global decline in the bee population is related to the use of insecticides, a fact that directly threatens the production of various foods. Honey, the main beekeeping product , is not only a source of food for bees, humans and other animals, but also an indicator of environmental quality, as its composition reflects the conditions of the environment in which it was produced, and determinations made therein can reveal the presence of contaminants such as pesticides and toxic metals providing information about ecosystem health and the presence of environmental contaminants. Furthermore, consuming pesticide-free foods is crucial for human health and environmental sustainability, as the intake of neonicotinoids is associated with several health problems such as hormonal disorders and nervous system diseases and is especially dangerous for children. This article reviews the neonicotinoid insecticides imidacloprid and thiamethoxam and the contamination they cause in the honey of bees Apis mellifera Linnaeus (1758) and Tetragonisca angustula Latreille (1811) in Brazil, evaluating the impacts of these insecticides on bees, the implications for ecosystems and safety to feed

Determination of per- and polyfluoroalkyl substances (PFAS) in six different fish species from Swiss lakes.

Per- and polyfluoroalkyl substances (PFAS) are persistent environmental contaminants with bioaccumulation potential, particularly affecting aquatic ecosystems and human health also via fish consumption. There is therefore a need for reliable extraction methods and studies to accurately assess PFAS levels in fish, crucial for understanding bioaccumulation and potential toxicological effects on both fish and humans through consumption. This study investigated PFAS levels in freshwater fish from Swiss lakes, focusing on six common species: Coregonus wartmanni, Cyprinus carpio, Oncorhynchus mykiss, Perca fluviatilis, Salmo trutta, and Squalius cephalus. Utilizing an optimized QuEChERS extraction method, 15 PFAS were analyzed in 218 fish fillet samples using liquid chromatography-mass spectrometry (LC-MS/MS). The results were compared to EU regulations and EFSA guidelines for tolerable weekly intake (TWI), with a specific focus on correlations between fish size and PFAS concentration. Our findings reveal significant PFAS contamination, particularly in Perca fluviatilis with perfluorooctane sulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS) levels often exceeding EU safety limits. TWI, calculated for a person of 70kg body weight and an intake of 200g of fish fillet, is exceeded in 95% of Coregonus wartmanni, 100% of Squalius cephalus, and in 55%, 50%, and 36% of the specimens Oncorhynchus mykiss, Salmo trutta, and Perca fluviatilis respectively. Correlation analysis between PFAS concentration and fish size in 121 Salmo trutta specimens revealed significant positive correlations for perfluorobutane sulfonic acid (PFBS), perfluorodecanoic acid (PFDA), and perfluorohexane sulfonic acid (PFHxS), and a negative correlation for perfluoropentanoic acid (PFPeA). These results underscore the critical need for continuous monitoring and regulatory efforts to mitigate PFAS exposure risks to both ecosystems and human health.

Kidney toxicology of a novel compound Lithium Bis(trifluoromethanesulfonyl)imide (LiTFSI, ie. HQ-115) used in energy applications: An epigenetic perspective

Exposure to emerging energy-based environmental contaminants such as lithium bis(trifluoromethanesulfonyl)imide (LiTFSI, trade name HQ-115), poses a significant threat to human health, yet its impact on kidney function and epigenetic regulation remains poorly understood. Here, we investigated the effects of LiTFSI exposure on kidney-related biochemical indicators, renal injuries, and epigenetic alterations in male CD-1 mice under both 14-day and 30-day exposure durations. Our study revealed that LiTFSI exposure led to changes in kidney-related markers, notably affecting serum bicarbonate levels, while relative kidney weight remained unaffected. Histological analysis revealed tubule dilation, inflammation, and loss of kidney structure in LiTFSI-exposed mice, alongside dysregulated expression of genes associated with inflammation, renal function, and uric acid metabolism. Epigenetic analysis further identified widespread DNA methylation changes in the two exposure regimes. Functional analysis revealed that differentially methylated regions are implicated in cell apoptosis and cancer-related pathways and are enriched with development-related transcription factor binding motifs, suggesting a potential mechanism of action underlying exposure induced kidney damage. These findings underscore the intricate interplay between environmental exposures, epigenetic modulation, and kidney health, emphasizing the need for additional research to unravel precise mechanisms and develop targeted interventions to mitigate the adverse effects of LiTFSI and exposure of similar clean energy compounds on human health.

"Groundbreaking study: Combined effect of marine heatwaves and polyethylene microplastics on Pacific oysters, Crassostrea gigas"

Microplastics (MPs) and rising marine seawater temperatures are one of the major environmental problems threatening the survival of marine organisms and biodiversity. However, interactions between such multiple stressors are virtually unexplored. This study aimed to assess the combined effect of two temperatures and polyethylene MPs on the Pacific oyster Crassostrea gigas, one of the most globalized mollusc species for aquaculture. Our work highlights the potential ecological risk posed by these two factors on marine bivalve molluscs. The experimental design was carried out following a 14-day exposure of oysters to environmental concentrations of polyethylene MPs (0.01 mg.L-1), and to two temperatures (15 °C and 22 °C). Sampling was performed on days 0, 7, and 14. The μ-FTIR analysis was applied to quantify MPs of interest and to check a potential environmental contamination. Tissue samples of digestive glands were collected from the oysters to evaluate the activity of biomarkers including superoxide dismutase, glutathione-s-transferase, malondialdehyde and laccase through protein levels. We note that the combination of MPs and high water temperature (HWT, 22 °C) had a significant impact both on the survival of animals and on stress markers, by modifying lipid peroxidation and immune responses. This original study gave the first innovative results on this topic and provides us with knowledge of the combined effects of MPs pollution and HWT (simulating marine heatwaves situation) on C. gigas. There remains a lack of information on the toxicity and the potential environmental hazard of plastics in the marine environment.

P-phenylenediamines (PPDs) and PPD-quinones (PPD-Qs) in human urine and breast milk samples: Urgent need for focus on PPD-Qs and the establishment of health threshold criteria

PPDs and their oxidation products, PPD-Qs, are emerging environmental contaminants arising from the addition and oxidation of rubber products. Although numerous studies have been conducted to elucidate their risks, the primary focus has been on 6PPD and 6PPD-Q, with limited attention given to other PPDs and especially other PPD-Qs. This study comprehensively examines the occurrences of frequently used PPDs and their degradation products, PPD-Qs, in human urine and breast milk samples. The average concentrations of ΣPPDs and ΣPPD-Qs in urine were 27 ± 78 ng/mL and 16 ± 12 ng/mL, respectively. IPPD and DNPD were the predominant PPDs, while DPPD-Q, CPPD-Q, and IPPD-Q were the predominant PPD-Qs. Notably, the concentrations of 6PPD, CPPD, and DPPD were significantly lower than their oxidized quinone products. Weak or no correlations were observed between most PPDs and their corresponding PPD-Qs, suggesting that PPD-Qs in the human body are primarily derived from direct environmental intake rather than in vivo conversion of PPDs. PPDs and PPD-Qs were widely detected in breast milk, exhibiting concentrations and patterns similar to those found in urine, with comparable major pollutants. Estimated daily intakes of PPDs + PPD-Qs for infants were several μg/(kg·day), with the 95th percentile intake approaching 10 μg/(kg·day).

Swift and Cost-Effective Detection of Nitrite in Environmental Samples Using Ru@Pt Modified PGE

The development of a straightforward method is crucial for detecting and quantifying nitrite ions within the surrounding environment. This study involves the electrochemical fabrication of a bi-metallic alloy composed of Ruthenium and Platinum on a graphene-modified pge, the first-ever electrodeposition on pencil graphite (RuNPs@PtNPs/Gr-CHI). This study aims to establish a highly responsive and specific approach for identifying nitrite ions while demonstrating the efficacy of a commercially available pencil graphite electrode in detecting this environmental contaminant. The prevalence and structural characteristics of bimetallic nanoalloy particles are confirmed through X-ray diffraction, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The composite exhibited a core–shell shape at a size of 26.998 nm. The electrooxidation of nitrite at RuNPs@PtNPs/Gr-CHI/PGE was investigated using differential pulse voltammetry. The results demonstrated a satisfactory linear relationship from 0.025 mM to 1.625 mM. The method revealed a low detection limit of 0.33 μM. The composite electrode exhibited favorable outcomes regarding selectivity, sensitivity (25.5 μAμM−1cm−2), and repeatability, which are desirable characteristics of the electrochemical sensor material. The constructed electrode underwent testing for five weeks to determine the stability. The suggested sensor’s capability is demonstrated by detecting nitrite ions in real samples such as water, soil, and fruit juice.

Multi-biomarker assessment of chronic toxicity induced by the chemical warfare agent adamsite in Danio rerio

Several hundred thousand tons of chemical warfare agents (CWAs) were disposed of at sea, leading to environmental contamination. Among the most toxic and persistent CWAs is adamsite; however, the ecotoxicological data on this compound is limited. Presented research focuses on the long-term effects of adamsite on fish. A 28-day exposure study was conducted, evaluating the impact of adamsite on life history parameters (body length, body mass, growth rate), tissue accumulation, and the expression/activity of detoxification-related enzymes in the model fish species, Danio rerio. Results indicate that chronic adamsite exposure significantly reduces body length, weight, and growth rate of fish at trace concentrations (0.20 and 0.25 μg × L−1). Adamsite-related compounds accumulate in fish muscle tissues, increasing by approximately 4 μg per gram (dry weight) for every microgram of adamsite per litre of water during chronic exposure. The mRNA expression and activity of detoxification-related enzymes were elevated in the gills of fish, indicating oxidative stress. This study highlights the severe chronic toxicity of adamsite, which could not be anticipated based on acute toxicity. It underscores the need for comprehensive long-term toxicity assays for CWAs and emphasizes the potential ecological and health risks posed by adamsite, necessitating more stringent risk assessments.