Search Results (864)

Industrial effluents pose a significant concern because they contain a variety of metals and metalloids that have detrimental effects on the environment. Conventional techniques are widely used in effluent treatment plants (ETPs) to remove metallic pollutants; however, they are less effective, are costly, and generate secondary toxic waste. Mycosorbent would be a sustainable and economical alternative to conventional techniques, as it offers numerous advantages. In this study, we shed light on the development of mycosorbent, which could be potentially applicable in the treatment of industrial effluent. In a competitive (i.e., multimetal system) optimisation study, mycosorbent AD2 exhibited a maximum biosorption capacity of 3.7 to 6.20 mg/g at pH 6.0, with an initial metal ion concentration of 25 mg/L, a contact time of 2 h, at 50 ± 2 °C, and a pH_PZC of 5.3. The metal-removal capacity increased up to 1.23-fold after optimisation. The thermodynamic parameters confirmed that the AD2 mycosorbent facilitated an endothermic, feasible, and spontaneous biosorption process. The FT-IR and SEM characterisation analysis confirmed the adsorption of metals on the surface of the mycosorbent from the aqueous system. This study demonstrated that mycosorbent could be an effective tool for combating metallic pollutants in various industrial effluents. Full article

In this study, Sr_0.95Bi_0.05TiO₃ was synthesized via solid state reaction, characterized, and applied as a visible-light-active photocatalyst for the degradation of oxytetracycline, imidacloprid, and their mixture. To evaluate the influence of the aqueous matrix on pollutant degradation, photocatalytic experiments were carried out in both distilled water and a real environmental sample (surface water). The Sr_0.95Bi_0.05TiO₃ perovskite showed high photocatalytic performance under visible light, achieving nearly complete degradation of oxytetracycline after 2 h, and significant removal of imidacloprid in river water (60% after 3 h). Enhanced degradation in surface water was attributed to favorable ionic composition and pH. The perovskite oxide maintained its photocatalytic performance over five consecutive cycles, with no significant loss in photocatalytic activity or structural and morphological stability. Ecotoxicological assessment using Daphnia magna confirmed that the treated water was non-toxic, indicating that no harmful byproducts were formed. Complementary Density Functional Theory calculations were conducted to complement experimental findings, providing insights into the structural, electronic, and optical properties of the photocatalyst, enhancing the understanding of the degradation mechanisms involved. This integrated approach, combining experimental photocatalytic performance evaluation in different matrices, ecotoxicity testing, and theoretical modeling, highlights Sr_0.95Bi_0.05TiO₃ as a promising, stable, and environmentally safe photocatalyst for practical wastewater treatment applications. Full article

Nanomaterials possess unique physicochemical properties that position them as promising candidates for environmental remediation, particularly in the removal of persistent organic pollutants (POPs) from aqueous systems. Their high surface area, tunable functionality, and strong adsorption capabilities have attracted significant attention. In this context, this paper reviews the mechanisms of nanomaterial-based POP decontamination, also providing a critical overview of the limitations and challenges in applying these methods. Specifically, issues of stability, reusability, and aggregation are discussed, which can lead to performance decay during repeated use. In addition, the practical application requires nanocomposites to enable efficient separation and mitigate agglomeration. Environmental concerns also arise from nanomaterials’ fate, transport, and potential toxicity, which may impact aquatic ecosystems and non-target organisms. When checking for large-scale application feasibility, impurities typically add to production costs, recovery problems, and general infrastructure limitations. In addition to these points, there are no standard guidelines or clear risk assessment procedures for registering a product. Unprecedented cross-disciplinary research between natural, human, and technological studies and outreach programs is needed to facilitate the development and diffusion of the results. The barriers will eventually be breached to move from laboratory success in developing the desperately needed new water purification technologies to field-ready water treatment solutions that can address the global POP contamination problem. Full article

This paper presents the assessment of the possibility of ammonia adsorption on biochars from banana peels, chemically activated with potassium hydroxide (KOH) at different temperatures. The obtained materials were characterized in detail using a number of analytical techniques, including nitrogen adsorption (BET), scanning electron microscopy (SEM), elemental analysis (CHNS), thermal analysis (TG, DTG, DTA), Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy, Boehm titration method and biochar surface pH. They revealed a largely developed microporous structure and a large specific surface area, ranging from 1134 to 2332 m² g⁻¹. The adsorption tests against ammonia in the gas phase showed a large adsorption capacity of the materials, up to 5.94 mmol g⁻¹ at 0 °C and 3.83 mmol g⁻¹ at 20 °C. The adsorption properties of the obtained biochars were confirmed to be significantly influenced by the surface chemistry (presence of the acidic functional groups). The research results indicate that the waste-based biomass, such as banana peels, can be an ecological and economical raw material for the production of highly effective adsorbents, useful in the removal of ammonia and other toxic gases polluting the environment. Full article

The extensive use of herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA), coupled with its limited biodegradability, has led to its ubiquitous presence in aquatic environments. This work investigates the removal of MCPA (100 mg/L) in the aqueous phase via solar photo-Fenton. The process was carried out in a 700 mL reactor using a Xe lamp that simulates solar radiation (λ: 250–700 nm). A parametric study was conducted to assess the influence of dissolved O₂ on the reaction medium, Fe²⁺ dosage, H₂O₂ concentration and pH₀. The results indicate that dissolved O₂ boosts pollutant mineralization, even working at sub-stoichiometric H₂O₂ concentrations. Under optimal reaction conditions ([Fe²⁺]: 7.5 mg/L, [H₂O₂]₀: 322 mg/L (stoichiometric dose), pH₀: 3.5), the MCPA reached almost complete mineralization (X_TOC: 98.40%) in 180 min. Phytotoxicity and ecotoxicity assessments of treated effluents revealed that even working at sub-stoichiometric H₂O₂ dosages, toxicity decreases with the solar photo-Fenton treatment. Finally, the solar photo-Fenton process was evaluated in relevant matrices (river water and WWTP secondary effluent) and a realistic pollutant concentration (100 µg/L). In all cases, the pollutant degradation was ≥70% in 60 min, demonstrating the potential of this technology as a tertiary treatment. Full article

Environmental xenobiotics, including heavy metals, endocrine-disrupting chemicals (EDCs), pesticides, air pollutants, nano- and microplastics, mycotoxins, and phycotoxins, are widespread compounds that pose significant risks to human health. These substances, originating from industrial and agricultural activities, vehicle emissions, and household products, disrupt cellular homeostasis and contribute to a range of diseases, including cancer and neurodegenerative diseases, among others. Emerging evidence indicates that epigenetic alterations, such as abnormal deoxyribonucleic acid (DNA) methylation, aberrant histone modifications, and altered expression of non-coding ribonucleic acids (ncRNAs), may play a central role in mediating the toxic effects of environmental xenobiotics. Furthermore, exposure to these compounds during critical periods, such as embryogenesis and early postnatal stages, can induce long-lasting epigenetic alterations that increase susceptibility to diseases later in life. Moreover, modifications to the gamete epigenome can potentially lead to effects that persist across generations (transgenerational effects). Although these modifications represent significant health risks, many epigenetic alterations may be reversible through the removal of the xenobiotic trigger, offering potential for therapeutic intervention. This review explores the relationship between environmental xenobiotics and alterations in epigenetic signatures, focusing on how these changes impact human health, including their potential for transgenerational inheritance and their potential reversibility. Full article

This study aims to evaluate the potential of Lemna minor (common duckweed) for the removal of galaxolide (HHCB) from polluted water, a compound commonly used in consumer products such as perfumes and detergents. The focus was to identify the optimal conditions for removal, determine the removal efficiency, and elucidate the mechanisms involved. The experiment was conducted by cultivating Lemna minor using as a cultivation medium synthetic sewage and laboratory solutions (MilliQ water) containing galaxolide at two levels of concentration (1034 µg·L⁻¹ and 2326 µg·L⁻¹). The plants were exposed to light for 16 h a day and grown at pH 5. Removal efficiency was assessed through liquid chromatography (HPLC) with fluorescence detection (FLD). Kinetics of observed process was modelled using a pseudo-first-order equation. The study of the HHCB decay mechanism included determining the contributions to the final effect of the following processes occurring simultaneously: sorption on the plant surface, photodegradation, and uptake by Lemna. The removal efficiency (RE%) of galaxolide by Lemna minor was 99.7% when aqueous standard solution was used as the cultivation medium after 14 days, and between 97.8% and 98.6% in the case of wastewater samples. Sorption onto plants surface, photodegradation, and uptake by the plants were identified as the primary mechanisms for HHCB removal. Toxicity studies revealed that galaxolide exposure adversely affected Lemna minor growth, altering photosynthetic pigments (chlorophyll and carotenoid) levels. Full article

Water quality is essential for safeguarding human health and ensuring the stability of ecosystems. Nonetheless, the rising prevalence of emerging contaminants, particularly pharmaceutical compounds, has raised serious environmental concerns due to their bioactivity, widespread use, persistence, and potential toxicity. Among these, acetaminophen (paracetamol) is one of the most frequently detected pharmaceutical pollutants in aquatic environments. Among the various degradation strategies explored, biological methods, especially those involving white-rot fungi, have shown substantial promise owing to their production of ligninolytic enzymes capable of degrading complex pollutants. This study investigates the use of laccases from Ganoderma parvulum, covalently immobilized on chitosan microspheres, for acetaminophen degradation. The immobilization involved a 10% crosslinking agent, 60-min crosslinking time, and 10,000 U/L enzyme concentration, resulting in an immobilization efficiency of 123%, 203%, and 218%, respectively. The immobilized enzymes displayed enhanced stability across pH 3–8 and temperatures between 20 and 60 °C. Biodegradation assays achieved 97% acetaminophen removal within four hours. Nuclear Magnetic Resonance (¹H NMR and COSY) confirmed structural transformation. The enzymes also retained over 95% catalytic activity after multiple reuse cycles. These findings highlight the novel application of laccases as efficient and reusable biocatalysts for pharmaceutical pollutant removal, providing valuable insights into the mechanisms of enzymatic environmental remediation. Full article

Tetracycline (TC) is widely used in medicine and livestock farming. TC is difficult to degrade and tends to persist and accumulate in aquatic environments, and it has gradually become an emerging pollutant. Biochar (BC) has strong potential for removing TC from water. This potential arises from its excellent surface properties, low-cost raw materials, and renewable nature. However, raw biomass materials are highly diverse, and their preparation conditions vary significantly. Modification methods differ in specificity and the application scenarios are complex. These factors collectively cause unstable TC removal efficiency by biochar. The chemical activation process using KOH/H₃PO₄ significantly enhanced porosity and surface functionality, transforming raw biochar into an activated carbon material with targeted adsorption capacity. Adjusting the application dosage and environmental factors (particularly pH) further enhanced the removal performance. Solution pH critically governs the adsorption efficiency: optimal conditions (pH 5–7) increased removal by 35–40% through strengthened electrostatic attraction, whereas acidic/alkaline extremes disrupted ionizable functional groups. The dominant adsorption mechanisms of biochar involved π–π interactions, pore filling, hydrophobic interactions, hydrogen bonding, electrostatic interactions, and surface complexation. In addition, the main challenges currently hindering the large-scale application of biochar for the removal of TC from water are highlighted: (i) secondary pollution risks of biochar application from heavy metals, persistent free radicals, and toxic organic leaching; (ii) economic–environmental conflicts due to high preparation/modification costs; and (iii) performance gaps between laboratory studies and real water applications. Full article

The metalloid arsenic (As) and the metals lead (Pb) and mercury (Hg), which together we call the “Toxic Triad”, are among the pollutants of greatest global concern, harming the health of millions of people and contributing to biodiversity loss. The widespread distribution of As, Pb and Hg facilitates the exposure of humans and other species to these elements simultaneously, potentially amplifying their individual toxic effects. While As, Pb and Hg are well established as toxic elements, the mechanisms by which they interact with genetic material and impact the health of various species remain incompletely understood. This is particularly true regarding the combined effects of these three elements. In this context, the objective of this work was to perform a toxicogenomic analysis of As, Pb and Hg to highlight multiple aspects of element-gene interactions, in addition to revisiting information on the genotoxicity and carcinogenicity of the Toxic Triad. By using The Comparative Toxicogenomics Database, it was possible to identify that As interacts with 7666 genes across various species, while Pb influences 3525 genes, and Hg affects 692 genes. Removing duplicate gene names, the three elements interact with 9763 genes across multiple species. Considering the top-20 As/Pb/Hg-interacting genes, catalase (CAT), NFE2 like bZIP transcription factor 2 (NFE2L2), caspase 3 (CASP3), heme oxygenase (HMOX1), tumor necrosis factor (TNF), NAD(P)H quinone dehydrogenase 1 (NQO1) and interleukin 6 (IL6) were the most frequently observed. In total, 172 genes have the potential to interact with the three elements. Gene ontology analysis based on those genes evidenced that the Toxic Triad affects several cellular compartments and molecular functions, highlighting its effect on stimulation of toxic stress mechanisms. These 172 genes are also associated with various diseases, especially those of the urogenital tract, as well as being related to biological pathways involved in infectious diseases caused by viruses, bacteria and parasites. Arsenic was the element with the best-substantiated genotoxic and carcinogenic activity. This article details, through a toxicogenomic approach, the genetic bases that underlie the toxic effects of As, Pb and Hg. Full article

Deciduous teeth accumulate toxic metals until fully mineralized, making them a stable biological matrix for assessing chronic exposure during fetal and early postnatal life. Their metal content is influenced by environmental factors (e.g., industrial areas, mining sites) and individual factors (e.g., maternal diet, early nutrition, passive smoking). The aim of this study was to evaluate the toxic metal content in deciduous teeth and to identify factors contributing to its accumulation, as well as possible health implications. A systematic review was conducted in accordance with the PRISMA guidelines and following the PICO framework. Quality assessment was assessed using the Joanna Briggs Institute (JBI) checklist for quasi-experimental studies. The literature search was carried out in the PubMed, Scopus, and Web of Science databases using the following keywords: deciduous, milk, primary, decidua, teeth, dentition, heavy metal, toxic metals. A total of 134 articles were initially identified, with 95 remaining after duplicate removal. After screening, 75 articles were excluded: 71 did not meet the inclusion criteria, 3 were not available in English, and 1 lacked full-text access. Ultimately, 20 studies were included in the review. Toxic metal concentrations were determined using various analytical techniques, mainly inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS). Higher levels of metals, especially lead, were observed in the teeth of children residing in industrial areas, near mines, or in regions affected by armed conflict. Although two out of five studies indicated a possible link between fathers’ smoking habits and elevated lead concentrations, no definitive relationship was established between secondhand smoke exposure and the levels of lead and cadmium found in dental tissue. Similarly, no definitive relationship was identified between mercury and lead content and the prevalence of autism. However, lower manganese levels were associated with the presence of autistic traits, weaker verbal performance, and reduced memory capacity. In conclusion, deciduous teeth represent a valuable biological material for assessing chronic prenatal and early postnatal exposure to toxic metals, which may serve as a starting point for further research into diseases of unknown etiology, such as autism, and in the future may have clinical significance in their prevention and treatment. And it is also important for monitoring environmental pollution levels. Full article

Since water contamination has become a serious concern, more effective environmental remediation methods are required. Chitosan (CHT)-based adsorbents have demonstrated high efficacy in removing pollutants due to their unique chemical and structural properties. However, their utilization remains limited by low environmental stability and the absence of effective adsorption sites. The functional moieties of CHT can be altered to improve its performance via graft modification and crosslinking. Compared to conventional hydrogel synthesis techniques, ionizing radiation-induced fabrication, using gamma or electron-beam irradiation, offers a promising platform for innovation across diverse fields. The prime focus of this review is on ionizing radiation developed CHT-based hydrogels to remove toxic heavy metals, dyes, organic contaminants, radionuclides, and humic substances. The fabrication strategy, adsorption mechanism, and factors affecting the adsorption capacity of CHT-based hydrogels are presented. This review aims to underscore the transformative potential of ionizing radiation-induced CHT hydrogels in environmental remediation by examining current research trends and identifying future prospects. Full article

The environment is undergoing a constant incorporation of new pollutants, which must be eliminated to avoid toxicity problems. Amoxicillin (AMX) is a widely used antibiotic today, and for this reason, it reaches natural media with the consequent environmental risk. Biosorption is an effective and environmentally friendly solution which can be used for the removal of AMX. In the present study, the properties of the living biomass of the microalga Chlamydomonas reinhardtii were studied to determine the capacity of this biomass to remove AMX. This biomass has demonstrated to have good qualities to remove AMX with a maximum capacity of 12.72 ± 0.57 mg g⁻¹. Light was an important factor in increasing the removal capacity of this living biomass by 35.2%. Although this antibiotic underwent spontaneous degradation (unaffected by light), the presence of the biomass increased the amount removed and the removal rate. The amount removed by this biomass in the presence of light was always higher than the amount lost by spontaneous degradation. The kinetics that best adjusted was pseudo-second order. Maximum removal was obtained at pH 6. A point of zero charge and Fourier transform infrared spectrometry were used to characterize the biomass and study the process. Full article

With the rapid development of the livestock farming industry, the treatment of livestock farming wastewater has become increasingly important. The microbial-algal biofilm method has gained widespread attention for cattle wastewater treatment owing to its non-toxic nature, resistance to shock loading, and high treatment efficiency. In this study, three types of substrates—polyurethane sponge, ceramic material, and moving bed biofilm reactor media—were evaluated. The formation of biofilms was assessed through variations in chlorophyll content, microscopic observations, and measurements of biofilm dry weight and attachment rate. Biofilm characterization on the different substrates was conducted via Fourier transform infrared spectroscopy, confocal laser scanning microscopy, and scanning electron microscopy. The results demonstrated that polyurethane sponge was the most effective substrate. Furthermore, a single-factor experiment was conducted to optimize the cultivation conditions for the microbial-algal biofilms and identify the optimal parameters based on the ability of the biofilm to remove COD, TN, TP, and NH₄⁺-N. The optimal conditions were as follows: an illumination intensity of 8000 lux, red light, a temperature of 20 °C, a pH of 7, and an aeration intensity of 8 L/min. Under these conditions, the pollutant removal rates were exceptionally high: ~73.4% for COD, 51.8% for TP, 57.0% for TN, and 75.1% for NH₄⁺-N. Full article