Search Results (1,789)

Mycotoxins are compounds produced by the secondary metabolism of certain fungi. These compounds contaminate foods worldwide and pose a severe threat to the health of humans and animals. They also cause huge economic losses. A plethora of methodologies, encompassing agricultural, biological, chemical, and physical approaches, have been devised to curtail the presence of mycotoxins in food commodities. Among the physical processes, cold plasma (CP) has emerged as a useful technique for controlling the presence of toxigenic fungi in foods and for degrading the mycotoxins occurring in them without significantly affecting the quality and organoleptic properties of the treated commodities. The present review endeavors to demonstrate the efficacy of CP as a method of eradicating or reducing both the toxigenic mycobiota and the mycotoxins present in the most contaminated foods, including nuts, dried fruits, and cereal grains. The mechanisms of toxin degradation proposed by the different researchers are also examined and compared. Furthermore, the impact of the CP effect on the quality, sensorial characteristics, and toxicological properties of the treated food is thoroughly examined. Full article

Cancer is attributed to being caused by multiple genetic, epigenetic, and various direct and indirect environmental factors. Microplastics are defined as pieces of plastic that are smaller than five millimeters. Microplastics have been emphasized as ubiquitous environmental contaminants found in terrestrial and aquatic systems, food webs, and the human body. Moreover, microplastics can bind to environmentally harmful pollutants, heavy metals, and refractory organic pollutants that can aggravate the biological effects of these pollutants. Microplastics are suggested to induce chronic inflammation, oxidative stress, and genotoxicity by adsorbing and modifying the biomolecules in the biological systems. Oxidative stress, inflammation, and chemical-induced genetic and epigenetic changes in cancer cells and cancer-associated cells are considered as crucial processes in the development, progression, and therapeutic outcome of cancer. Among numerous tumor-promoting environmental factors, preclinical and clinical evaluations of how microplastics contribute to cellular and non-cellular pro-tumorigenic mechanisms like inflammation, genomic instability, and epigenetic modulation are emerging. This review will contribute to a better understanding of microplastics as additional environmental components apart from established carcinogens and genotoxic substances that directly or indirectly influence the pro-tumor microenvironment. Full article

Conventional wastewater treatment systems cannot effectively eliminate micropollutants such as contaminants of emerging concern (CECs). These compounds, even at trace levels, are persistent or pseudo-persistent, bioaccumulative, and potentially harmful to ecosystems and human health. Advanced oxidation processes (AOPs), based on the in situ generation of highly reactive oxygen species, have emerged as promising solutions. Peroxyacetic acid (PAA) has gained attention due to its strong oxidizing capacity, broad antimicrobial activity, environmentally benign by-products, and compatibility with different activation methods. This review provides an updated and integrated synthesis of recent advances in PAA-based AOPs for the degradation of major CEC groups, including pharmaceuticals, personal care products, pesticides, and industrial chemicals, as well as for the oxidative modification of microplastics (MPs). The review discusses several strategies for PAA activation and critically discusses removal efficiency, underlying mechanisms, and current limitations, emphasizing the gap between pollutant transformation and complete mineralization. Furthermore, the article highlights a key research need, which is the assessment of the toxicity of transformation products and their validation under realistic conditions. Overall, this review provides insight into the potential and challenges of PAA-based AOPs for sustainable water treatment. Full article

The uncontrolled discharge of synthetic azo dyes such as methyl orange (MO) into water bodies has become a major environmental concern because of their strong chemical stability, limited biodegradability, and harmful effects on aquatic ecosystems. In this study, MgNiFe layered double hydroxides (LDHs) were synthesized through a co-precipitation route using a molar ratio of (Mg + Ni)/Fe equal to 3, and their adsorption ability toward MO in aqueous media was investigated. The prepared materials were characterized by X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDX), Fourier-transform infrared spectroscopy (FTIR), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The characterization results revealed the successful formation of a hydrotalcite-like layered structure with good crystallinity, a relatively uniform distribution of metallic species, and the incorporation of carbonate anions within the interlayer galleries. In addition, the adsorption performance was evaluated by studying the effects of several operational factors, namely adsorbent dosage, initial pH, and contact time. To better understand the interaction between these parameters and identify the optimum operating conditions, a Box–Behnken response surface design was applied. The results indicate solution pH is the most influential parameter in the adsorption process. Under optimized conditions, a maximum removal efficiency of 86.86% was obtained, corresponding to an adsorption capacity of approximately ~86.86 mg·g⁻¹ (based on 100 mL solution volume). The enhanced adsorption performance may be attributed to the combined effect of the multivalent metal cations (Mg²⁺, Ni²⁺, and Fe³⁺), likely increases the surface positive charge density of the LDH and promotes interactions with anionic dye molecules. These interactions are suggested to involve electrostatic attraction and possible surface adsorption processes. However, in the absence of post-adsorption characterization, the exact adsorption mechanism remains hypothetical. Overall, the results demonstrate the promising potential of MgNiFe LDHs as efficient adsorbent materials for the treatment of dye-contaminated wastewater. Full article

Chitosan (CS) was employed to modify coconut shell activated carbon (CAC) to fabricate a composite adsorbent for wastewater treatment. By integrating the functional groups of CS with the high specific surface area of CAC through chemical modification, the resulting CS-AC composite exhibited significantly enhanced adsorption performance toward hexavalent chromium (Cr(VI)) in aqueous solutions. The effects of key parameters, including adsorbent dosage, initial Cr(VI) concentration, contact time, temperature, and solution pH on the adsorption efficiency were systematically investigated. Under optimal conditions, the CS-AC composite achieved a Cr(VI) removal efficiency of up to 99.04%. Kinetic and isotherm modeling revealed that the adsorption process followed the pseudo-second-order kinetic model and was well described by the Langmuir isotherm. Regeneration studies conducted over five consecutive adsorption-desorption cycles demonstrated that the composite retained a high removal efficiency of 98.10%, indicating excellent reusability. These findings suggest that the CS-AC composite is a promising and effective adsorbent for the removal of Cr(VI) from contaminated water. Full article

Tetracycline (TC) contamination in reservoirs poses environmental and human health risks, particularly antibiotic resistance in ecosystems. Bagasse fly ash (BFA), a by-product from the sugarcane processing industry, has gained attention as an environmentally friendly adsorbent. In this study, we aimed to investigate the mechanism of TC adsorption using batch experiments to evaluate the effects of various factors. For example, pH value ranged from 4 to 10, contact time varied between 0 and 90 min, adsorbent doses were noted as 0.5–2.5 g per 50 mL, the initial concentrations of TC were 10–40 mg/L, and the temperature ranged from 293.15 to 318.15 K. To perform surface characterization of BFA, we employed the scanning electron microscopy (SEM) technique. Based on the results of Fourier transform infrared spectroscopy (FTIR) and surface area analysis (Brunauer–Emmett–Teller; BET), its structure and chemical properties are favorable for TC adsorption. Our results demonstrate that the optimal conditions for adsorption were at pH 7.0 and 60 min contact time. The adsorption capacity tended to increase with the initial concentrations of TC and reached a maximum of 0.58 mg/g when the initial concentration was 40 mg/L. Our kinetic analysis results demonstrate that the pseudo-second-order model exhibited the best fit with the experimental data (R² = 0.95638); in comparison, the results of the isotherm behavior study using the Temkin model (R² = 0.97338) indicated the complex adsorption pathway on the BFA surface. Full article

This study explores the use of metallurgical slag extracts as a liquid mineral fertilizer for maize cultivation. Slag samples were obtained from the former lead smelter in Shymkent and the Zhezkent Mining and Processing Plant. Elemental analysis identified the slag from the second storage area of the Shymkent smelter as the least contaminated with potentially toxic elements and enriched in macro- and micronutrients. Slag extraction was conducted via chemical leaching using potassium sulfate and ammonia solutions in a hydrogen peroxide medium, yielding Cu²⁺ and Zn²⁺ concentrations of 423.751 mg/L and 86.649 mg/L, respectively. The resulting extracts were diluted with distilled water at a ratio of 1:10 (potassium sulfate extract) and 1:200 (ammonia extract) and applied to assess early seed development and subsequent maize yield. Seed germination rates were comparable to those of the control group (100%). After 90 days of growth, maize plants treated with the ammonia-based extract showed positive effects on root system development, stem growth, and cob formation. The concentration of potentially toxic elements in the dry plant biomass remained within permissible limits. These findings demonstrate the potential for the safe agricultural use of these extracts while ensuring the rational utilization of industrial waste. Full article

The deposition of volcanic ash in areas affected by erupting volcanoes can contaminate the soil with heavy metals, thereby jeopardizing food security and public health. This study focused on the use of compost for the bioremediation of this type of contaminated soil and on evaluating the effectiveness of this remediation technique in a horticultural crop. To this end, composts made from organic waste generated in the areas with volcanic-ash-affected soil, such as crop residues, cow manure, and cheese whey, were used. The design and optimization of the composting process for these wastes were described using three piles with the same proportion of crop residues and cow manure but different doses of whey (pile 1: without whey, pile 2: whey diluted with water (1:2 (v:v)); and pile 3: with undiluted whey) and by monitoring the evolution of physicochemical and biological parameters throughout the compositing process. The effectiveness of the composts obtained for soil remediation was evaluated by assessing the physiological response of a lettuce crop in pots. Five treatments were used: control soil without fertilization, inorganic fertilization, and the three composts obtained. The main agronomic properties of the soil and heavy metal availability were measured, along with the physiological and chemical parameters of the lettuce, including growth and macronutrient and heavy metal content. The results obtained in the composting experiment showed that the addition of cheese whey only affected the rate of organic matter degradation and the salt content of the final composts, without negatively affecting the stability and humification of their organic matter or their plant nutrient content. In the pot experiment, all composts improved soil fertility and reduced the availability of Ni, As, Cd, and Pb, but this did not consistently reduce uptake into lettuce, except in the case of Pb. Therefore, it is advisable to adjust the compost application rate and optimize crop selection to minimize the impact of heavy metals on the food chain, thereby ensuring safe production. Full article

Given the increasing concern around greenhouse gas emissions and the decline in the availability of fossil fuels, there is increasing global demand to develop alternate fuels for maritime transportation that are sustainable and which have lower greenhouse gas emissions. Methanol is one such alternative fuel that has garnered considerable attention given its potential to be produced by more sustainable processes and its more favorable greenhouse gas emission profile in comparison with current fossil fuels. Understanding the physical and chemical properties of methanol under a range of conditions is essential for its development as a marine fuel. In this study, we seek to define physical and chemical properties of different methanol samples to simulate real-world storage conditions as these data are lacking in the literature. Several methanol samples were evaluated: nearly pure methanol; International Organization for Standardization (ISO) marine methanol (MM) grades A, B, and C; and methanol plus higher alcohols. We first evaluated all methanol samples for impurities, acetic acid content, density, and distillation range. We then characterized the effects of water absorption and found that methanol can easily absorb unacceptable water content from humid air within hours, necessitating storage conditions that prevent this process. In eight-week aging experiments at 20 °C and 40 °C in ambient air, we did not observe significant oxidation for any of the methanol samples; however, we did observe increases in acid number. We assessed the impact of contamination of methanol with water, marine gas oil (MGO), and an MGO–biodiesel mixture on density, viscosity, distillation range, and lubricity. Finally, we show that MGO contamination of methanol results in a slight increase in sooting tendency. In aggregate, our results provide an in-depth analysis of physical and chemical properties of methanol as well as the impacts of storage conditions and impurities on the properties of fuel methanol. Full article

Background/Objectives: Aim: Dental practice involves continuous exposure to saliva and blood, creating persistent opportunities for cross-infection if contaminated instruments are not processed correctly. This study aimed to evaluate dental students’ knowledge regarding blood-borne infections and infection prevention measures, and to compare knowledge levels according to academic year and sex. Materials and Methods: A structured questionnaire consisting of 21 single-best-answer questions was administered to 93 undergraduate dental students (Years I–VI) from the Faculty of Dental Medicine, “Gr. T. Popa” University of Medicine and Pharmacy, Iași, Romania. The questionnaire evaluated knowledge related to instrument classification, cleaning and disinfection procedures, sterilization parameters, autoclave monitoring tests, and storage conditions. Demographic data were also collected. Statistical analysis was performed using IBM SPSS Statistics version 31, and associations between responses and demographic variables were assessed using chi-square tests. Associations between responses and demographic variables (academic year and sex) were evaluated using chi-square tests (p < 0.05). Results: Most participants correctly identified several key steps in the instrument processing circuit, including the use of high-level disinfectant–detergent solutions (88.2%) and the need for disinfection followed by sterilization (76.3%). However, important knowledge gaps were identified regarding autoclave pre-use checks, correct sterilization temperatures and exposure times, recommended sterile storage periods, and the interpretation of sterilization monitoring tools such as type 5 chemical integrators, Bowie–Dick tests, and Helix tests. Knowledge levels differed significantly according to academic year (p < 0.05). Conclusions: Although overall awareness of instrument processing procedures among dental students was generally satisfactory, several inconsistencies were observed in critical technical aspects of sterilization and monitoring. These findings highlight the need for strengthened infection control education and repeated practical training to reduce the risk of cross-infection in dental practice. Full article

Sewage sludge (SS) is a by-product of wastewater treatment processes (WWTPs) and is rich in organic matter and essential nutrients like nitrogen, phosphorus, and potassium, making it a potential fertilizer for agricultural use. However, its application is often limited due to the presence of pathogenic bacteria, viruses, metals, and organic contaminants that can accumulate in soils and crops, raising concerns about food safety. Sewage sludge is additionally challenging to handle due to its high moisture content, low density, and odor emission. To mitigate environmental risks and enhance its usability as a soil fertilizer, SS must be stabilized. Various techniques, including chemical, physical, and biological, can be used to stabilize SS. The addition of lime and composting has received particular attention among these techniques owing to the benefits they offer. Both methods effectively control and eliminate pathogens and reduce metal bioavailability, thus improving their agricultural utility. This review emphasizes the importance of using SS for agricultural purposes, placing particular focus on the procedures of composting and liming to stabilize and enhance the quality of SS, hence promoting its safety. Full article

This study investigates the removal of Cd²⁺ ions from aqueous solutions using hard magnetic strontium hexaferrite (SrFe₁₂O₁₉) nanoparticles synthesized via the Pechini method, with an average particle size of 116 nm. The material was successfully obtained at a relatively low calcination temperature of 900 °C. The crystalline structure of the hexaferrite particles was investigated by X-ray diffraction, confirming SrFe₁₂O₁₉ crystalline structure. The powder samples were also characterized by Fourier transform infrared spectroscopy (FTIR). The morphology and size distribution were studied using scanning electron microscopy (SEM). Furthermore, the magnetic properties of strontium hexaferrite contribute significantly to adsorption and removal processes, primarily by acting as a recoverable magnetic adsorbent. The ferromagnetic material, with its high saturation magnetization and coercivity, responds rapidly to external magnets, facilitating the removal of contaminants and maintaining its magnetic characteristics even in complex chemical environments. For this purpose, its magnetic behavior was also studied using vibrating sample magnetometry (VSM). The experimental adsorption results were successfully modeled using PFO (pseudo—first—order) and PSO (pseudo—second—order) along with Freundlich and Langmuir isotherms, to fit the experimental adsorption data of the Cd(II) salt from the 0.1 and 0.2 mg samples at room temperature for two quantities of strontium hexaferrite at times ranging from 2.5 to 60 min. The results indicate that the strontium hexaferrite nanoparticles exhibited a 90% removal efficiency, which was the highest value. Additionally, the strontium hexaferrite can be magnetically recovered along with the adsorbed cadmium, representing a more efficient way to remediate water. Full article

Per- and polyfluoroalkyl substances (PFASs) in fluorinated firefighting wastewater (FFW), which are difficult to remediate using conventional technologies, represent a critical environmental hazard due to the extreme persistence and bioaccumulation potential of soil–groundwater systems. Niobium-supported boron-doped diamond (BDD) anodes were synthesized by microwave plasma chemical vapor deposition, and their performance in the electrochemical advanced oxidation processes (EAOPs) of FFW were systematically investigated. Under optimized conditions (100 mM Na₂SO₄ electrolyte with 100 mM peroxymonosulfate (PMS), current density of 33.3 mA/cm², pH = 6), the BDD anode achieved near-complete mineralization, with 92.5% total organic carbon (TOC) removal and significant defluorination (77.5% F⁻ release) within 240 min in simulated FFW-contaminated groundwater. For FFW-contaminated soil remediation, 90.2% TOC removal and 41.6% defluorination were achieved after 720 min under optimal treatment (water-to-soil ratio of 20:1). Quenching experiments and electron paramagnetic resonance (EPR) tests revealed that hydroxyl radicals (·OH) and singlet oxygen (¹O₂) were the predominant reactive species. Liquid chromatography–mass spectrometry/mass spectrometry (LC-MS/MS) analysis indicated that PFASs were removed by shortened carbon chains, ultimately mineralizing to CO₂ and F⁻. Toxicity assessment using Vibrio fischeri luminescence demonstrated a reduction in toxicity (from 99.8% to 20.9%), confirming the effective detoxification of BDD-based EAOPs. This work establishes BDD-based EAOPs as a promising technology for eliminating PFASs in groundwater and soil, offering theoretical insights into EAOPs and engineering solutions for PFAS remediation. Full article

The printed circuit board (PCB), a central component of most electronic devices, represents a significant fraction of the electronic product waste stream. The complex composition of PCBs, consisting of metals, polymers, and fiberglass, requires specialized recovery steps to reclaim valuable and critical materials and the safe disposal of brominated compounds. In this review paper, we describe the current state of critical material recovery and traditional recycling technologies and identify key obstacles to large-scale implementation. Metals present at high concentrations, such as copper, lead, and iron, are conventionally recovered from PCBs using hydrometallurgical, pyrometallurgical, or electrometallurgical processes. Hydrometallurgical methods achieve high selectivity through chemical leaching but pose significant challenges for effluent and reagent recovery. Pyrometallurgical methods facilitate rapid metal separation through smelting but require substantial energy and may release harmful gases. Electrometallurgical techniques produce high-purity metals but are constrained by pretreatment requirements and the consumption of energy. The non-metallic fraction of PCB waste is recycled using thermochemical conversion, microwave-aided heating, and direct recycling of epoxy–fiberglass composites, enabling material or energy recovery. The recovered polymer from direct recycling may have reduced mechanical strength and poor compatibility with new polymer matrices, and the resulting products from the thermal conversion suffer from incomplete conversion, degradation of quality, and residual contamination, as compared to synthetic polymers. Recent process developments have focused on extracting rare earth and supply-critical materials present at lower concentrations in the waste stream. The literature on existing and emerging approaches for recycling PCB wastes is reviewed to identify sustainable, economically viable, and environmentally responsible strategies for the recovery and reuse of critical materials from waste streams. Full article

Domestic wastewater is a chemically complex and highly variable mixture of pollutants generated by everyday household activities, yet its contribution to environmental contamination is still frequently underestimated and only 56% of wastewater worldwide is being treated. This review provides a structured and quantitative assessment of major domestic wastewater pollutant groups, their principal exposure pathways, and current and emerging treatment technologies. Beyond a conventional narrative synthesis, the review derives per capita annual emission estimates from published data and uses these to compare pollutant groups by mass flow and environmental relevance. The analysis shows that high-volume household inputs, particularly sodium chloride from domestic water softening, toilet paper, personal-care products, detergents, and cleaning agents, can contribute substantially to overall pollutant loads, whereas lower-mass contaminants such as pharmaceuticals, antibiotics, PFAS, heavy metals, and microplastics remain critical because of their persistence, biological activity, and incomplete removal during treatment. The review further highlights that conventional wastewater treatment systems are often poorly equipped to remove many of these emerging contaminants effectively, especially under decentralised or only partially advanced treatment conditions. Advanced and hybrid technologies, including membrane bioreactors, nanofiltration, reverse osmosis, adsorption, photocatalysis, and electrochemical processes, offer clear potential, but their broader implementation remains constrained by cost, energy demand, fouling, and concentrate management. Overall, the added value of this review lies in linking mass-based pollutant prioritisation with treatment performance, thereby providing a more systematic basis for identifying dominant household emission pathways and for guiding targeted mitigation and technology selection in future wastewater management. Full article