Search Results (1,759)

The utilization of oil sludge for the creation of value-added petroleum products represents an important research direction, as certain processing routes do not incur the additional costs that are associated with more complex refining operations. The selection of the most appropriate treatment method is therefore critical for achieving cost-effective processing outcomes. The economic feasibility of a particular technology is largely determined by the physical–chemical properties and potential toxicity of oil sludge, and thus, it is essential to comprehensively characterize and assess the toxicity of this substance. In this study, the physical–chemical composition and principal characteristics of oil sludge obtained from a Kazakhstan oil company were examined. To clean the oil sludge, an alkaline solution was used as a surfactant with a solid–liquid ratio of 1:3. The solid content in the sludge was reduced from 23% to 0.76%. The results revealed that the hydrocarbon fraction of the oil sludge was predominantly composed of heavy fractions. In addition, the effects of thermal parameters on treatment efficiency were found to contribute to the secondary products present in high oil fractions. Treatment with inert gases improved processing efficiency rates by over 57%. The most efficient results included the pyrolysis of cleaned oil sludge with minimum solid residues (5.8% under CO₂) and maximum gas products (37.8% under N₂). Full article

Bottom sediments play a central role in regulating contaminant dynamics in aquatic systems. They act as both storage sites and reactive zones where contaminants undergo transformation, sequestration, or remobilization. Contaminants primarily enter sediments through anthropogenic activities, including agricultural runoff, industrial effluents, wastewater discharge, urban runoff, and mining operations. This review focuses on six major contaminant groups, including nutrients, heavy metals, pharmaceutical residues, pesticides, polycyclic aromatic hydrocarbons, and microplastics, and examines the mechanistic processes that govern their fate in sediments. The main mechanisms includesorption–desorption on minerals and organic materials, sedimentation, and redox processes that regulate metal immobilization and sulfide formation. The persistence and mobility of contaminants are also influenced by synergistic or antagonistic interactions among pollutants, microbial transformation of organic compounds, and oxidative degradation of microplastics by reactive oxygen species. Contaminants can affect benthic communities by causing toxic effects and oxygen depletion. They also may alter microbial and macrofaunal populations and contribute to bioaccumulation and biomagnification. Ultimately, these insights are important for predicting contaminant behavior and assessing ecological risks, which directly informs the development of effective environmental monitoring programs and sustainable sediment remediation strategies for the long-term protection of aquatic ecosystems. Full article

This study aimed to conduct a first evaluation of maternal exposure to mycotoxins during pregnancy in Brazil through quantification of biomarkers in liver and serum samples from stillborn and neonates autopsied in the Clinical Hospital of Ribeirão Preto, state of São Paulo. Liver tissue (n = 43) and serum (n = 38) samples were collected from 43 patients and analyzed for biomarkers of aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FBs), zearalenone (ZEN), deoxynivalenol (DON), T-2 and HT-2 toxins by ultra-performance liquid chromatography coupled to tandem mass spectrometry. In total, 9 samples of liver (20.9%) and 33 serum (86.8%) had quantifiable levels of mycotoxins. In liver samples, aflatoxin M₁ (AFM₁) was quantified in two samples (median level: 0.38 ng/g), while four samples had OTA residues (median: 0.31 ng/g) and one contained ZEN (3.6 ng/g). Compared with liver tissue, serum samples had higher occurrence rates of mycotoxins, particularly AFM₁, OTA and ZEN. Nineteen serum samples (50%) contained 2–4 types of mycotoxins, indicating an effective transplacental transfer of major mycotoxins during pregnancy. Median levels of AFM₁, OTA, FB₁, ZEN, DON, T-2 and HT-2 toxins in serum samples were 0.48, 3.39, 30.6, 10.53, 5.71, 2.85 and 10.84 ng/mL, respectively. The most frequent cause of death was extreme prematurity (33% of cases), followed by preterm premature rupture of membranes (16% of cases) and morphological abnormalities (42% of cases). Results of this trial suggest potential associations between dietary mycotoxins and congenital anomalies. Further research should clarify the transplacental transfer of mycotoxins and their association with toxic effects during human prenatal development. Full article

Most tropical soils, as in the case of Brazil, are highly weathered, with low fertility, high acidity, and toxic aluminum, which limits crop management. Promoting root development is essential to overcome these constraints, and agricultural gypsum has shown positive effects in no-tillage systems. This study evaluated the residual effects of five gypsum rates in an integrated crop–livestock system, with or without inoculation of rotation grasses with Azospirillum brasilense, on crop productivity and soil fertility over 40 months. The experiment was conducted in a randomized block design with four replications in a 5 × 2 factorial scheme. Inoculated grasses increased yields of soybean, sorghum intercropped with Paiaguás grass, and black oat, whereas non-inoculated areas had the highest corn yield, likely due to hybrid metabolism. Gypsum had limited effects on crop yields, with lower doses performing slightly better. Inoculation improved soil fertility, increasing base sum, cation exchange capacity, and base saturation up to 0.60 m depth at 18 and 40 months. After 40 months, gypsum enhanced soil conditioning and increased calcium, sun of bases, and base saturation. Overall, inoculation with Azospirillum brasilense in rotation grasses under long-term no-tillage systems enhanced crop productivity and contributed to improved soil fertility. Full article

A four-year survey was conducted to monitor the presence of multiple pesticide residues contaminating tomatoes, with the aim of evaluating the potential health and environmental risks. A multiresidue liquid chromatography–triple mass spectrometry with a multiple reaction monitoring (LC-MS/MS-MRM) method was fully validated and used to test 252 pesticides in 360 samples analysed. According to SANTE guidelines, the proposed method was considered suitable for the purpose. Dietary risk assessment was conducted using the Hazard Quotient (HQ) approach and the European Food Safety Authority (EFSA) Pesticide Residue Intake Model; meanwhile, the cumulative environmental risk assessment was conducted using the Concentration Addition (CA) and Independent Action (IA) methods. Data obtained revealed multiple contaminations in most fields examined over the years. Twenty-two pesticide residues were identified, comprising 68.2% fungicides, 27.3% insecticides, and the remaining 4.5% acaricides. Higher levels were detected for Boscalid in 2022 in three fields, with an average value of 0.42 mg/kg. Multi-residue contamination occurred each year; the lowest abundance was detected in 2023 (3.9%), and the highest in 2022 (12.3%), with 5 pesticide residues as the maximum number of compounds detected in one sample in 2022. The consumer risk assessment identified no potential health concerns for adults or toddlers, and the combined risk was considered acceptable. The environmental assessment showed maximum cumulative ratio (MCR) values that were always ≥1, indicating a contribution to the toxicity of the mixture, only slightly higher than that of the single compound with the highest toxicity. The results of this study highlight the critical need to include cumulative dietary exposure assessments in pesticide risk evaluations, especially for food products that are susceptible to contamination by multiple residues. Full article

Accurate detection of residual jellyfish venom is crucial for species identification and clinical management post-envenomation. We developed a highly specific immunoassay for Nemopilema nomurai venom using polyclonal antibodies (titer: 1:256,000). The established i-ELISA exhibited linear detection (0–20 ng/mL) with low variability (intra-plate CV: 0.77–2.78%; inter-plate CV: 2.25–5.17%). The kit demonstrated remarkable thermal stability (<15% signal decay after 6 days at 37 °C; detectable positivity through Day 9), suggesting >1-year shelf life at 4 °C. It showed significantly higher sensitivity for N. nomurai venom than venoms from Rhopilema esculentum, Chrysaora quinquecirrha, Cyanea melanaster, scorpions, or bees (p < 0.01). Validation in murine/human skin envenomation models and serum from systemically intoxicated mice confirmed the reproducibility and stability of residual toxins. This study developed a highly sensitive, specific, reproducible, and stable i-ELISA for Nemopilema nomurai venom, providing a methodological basis for creating diagnostic kits for marine envenomation. Full article

Plant essential oils offer eco-friendly alternatives to insecticides, though their instability limits effectiveness. This study evaluated the physicochemical stability and fumigant efficacy of geranium (Pelargonium graveolens) oil nanoemulsion (GONE) versus bulk geranium oil (GOB) against Callosobruchus maculatus. Geranium oil nanoemulsions (GONEs) were prepared via spontaneous emulsification using 8% oil and varying surfactant levels. The 10% surfactant formulation produced the most uniform and stable nanoemulsion, with an average droplet size of 91.85 ± 0.02 nm and a low polydispersity index of 0.16 ± 0.02. No significant changes in droplet size were observed after 30 days of storage at room temperature and 9 °C, confirming the formulation’s stability. A fumigant bioassay was conducted using five concentrations (50, 100, 150, 200, and 250 µL/L air) of GOB and GONE over 24, 48, 72, and 96 h. Both forms exhibited concentration- and time-dependent toxicity against C. maculatus. Complete mortality was achieved sooner and at lower doses with GONE (72 h at 150 µL/L air versus 250 µL/L air for GOB; 96 h at 150 µL/L air for GONE versus 200 µL/L air for GOB). Geranium oil nanoemulsion consistently produced lower LC₅₀ and LC₉₀ values, indicating greater potency. It also significantly reduced progeny development. Residual fumigant bioassays at the LC₉₀ level showed that GONE retained efficacy against C. maculatus adults longer than GOB, causing 50% mortality 12 days post-treatment compared to 21% for GOB. Overall, nanoformulation enhanced the potency and persistence of geranium oil, highlighting its promise for protecting stored grains from C. maculatus. Full article

Olive mill wastewater is a polluting residue generated from the olive oil industry and is one which constitutes an environmental concern in Mediterranean countries. Composting has been reported as a viable valorization alternative, as it reduces the volume and the phytotoxic characteristics of OMW. In this study, several composts derived from OMW were evaluated under controlled conditions over two growing season pot experiments using Lactuca sativa as a test crop. The analysis focused on soil quality changes, crop yield, and plant development. Additionally, potential phytotoxicity was also evaluated through a direct acute toxicity plant growth test. Application of OMW composts improved soil fertility indicators, including oxidizable carbon, Kjeldahl total nitrogen, Olsen phosphorous, and plant availability. Crop yields were comparable to those obtained with other organic amendments such as vermicompost and fresh cattle manure in both growing seasons and plant development (in terms of chlorophyll content and canopy cover) was not negatively affected. Nutrient uptake (NPK) was consistent during both growing seasons, with similar nitrogen use efficiency to that achieved in other organic treatments. Regarding the potential toxic effect, the OMW composts tested enhanced seed germination when mixed with coconut fiber at weight ratios below 29.2%. No half-maximal effective concentration (EC50) values were detected, even at 100% compost concentration, while half-maximal inhibitory concentration (LC50) values ranged between 65–75%. These results indicate that OMW composts can serve as an effective short-term source of plant-available nitrogen and a medium-term source of phosphorus, without risk of finding inhibitory or phytotoxic effects on crops. Full article

Gasoline alkali residue raw liquid, a kind of highly toxicity containing organic waste generated during petroleum refining, is characterized by its complex composition, high pollutant levels, and significant emission volume. The effective treatment of this wastewater remains a considerable challenge in environmental engineering. This study systematically investigates the degradation efficiency and mechanism of Fenton oxidation in reducing the chemical oxygen demand (COD) of raw gasoline alkali residue sourced from Kashi. The effects of H₂O₂ concentration and the H₂O₂/Fe²⁺ molar ratio on COD and TOC removal were examined. Results demonstrated that the COD and TOC removal efficiency exhibited an initial decrease followed by an increase with rising concentrations of Fe²⁺ and H₂O₂. Comparative assessment of different combined Fenton processes revealed distinct mechanistic differences among the composite oxidation systems. The integration of pretreatment with UV-Fenton oxidation was identified as the optimal strategy. Under optimal conditions (pH = 3.0, H₂O₂ concentration = 1.0 mol/L, H₂O₂/Fe²⁺ molar ratio = 5:0.10), the COD was reduced from 25,041 mg/L to 543 mg/L, achieving a COD removal rate of 97.8%. This study elucidates the reaction mechanism of the Fenton system in treating alkali residue and provides a theoretical foundation for the advanced treatment of high-concentration organic wastewater. Full article

Methacrylate photopolymer resin (MPR) is widely used in various fields, including the biomedical field. There are several problems associated with their use: the potential toxicity of monomer residues during incomplete polymerization and the possibility of bacterial expansion. Doping polymers with nanoparticles is one of the ways to increase the degree of polymerization (protection from toxicity), improve the performance characteristics of the polymer, and add antibacterial properties. We used an in situ polymerization method to obtain the composites of MPR with tellurium nanoparticles (TeNPs) with a dopant concentration of 0.001, 0.01, or 0.1% (v/v). The composite of MPR+TeNPs had a higher degree of polymerization compared to MPR without NPs, improved mechanical properties, and pronounced antibacterial activity. The effects depended on the concentration of TeNPs. All of the studied composites had no cytotoxic effect on human cells. MPR+TeNPs 0.1% had the maximum antibacterial effect, which is probably realized through Te-dependent induction of oxidative stress (increase in the generation of 9-oxoguanine and long-lived reactive forms of proteins). The results obtained deepen the knowledge about the influence of NPs of leading metals on photopolymerization and the final properties of the methacrylate matrix, and the synthesized MPR+TeNP composites may find potential biomedical applications in the future. Full article

The overuse of pesticides has raised serious food-safety and environmental concerns. Carbon dots (CDs) can act as biostimulants by enhancing photosynthesis, thereby promoting plant growth and stress tolerance. However, their roles in plant pesticide detoxification remain unclear. This study synthesized nitrogen-doped carbon dots (N-CDs) with strong blue fluorescence, excellent biocompatibility, and no cytotoxicity observed in HEK 293T cells. The N-CDs were synthesized from 1.025 g citric acid and 0.379 g urea, producing particles with a size of around 2.42 nm and abundant hydrophilic groups. When applied to tomato plants, N-CDs (especially at 150 mg·L⁻¹) significantly reduced chlorothalonil (CHT) residues affecting tomato, by up to 66%. Importantly, N-CDs also improved tomato plant growth, reversing the negative effects of CHT on key parameters such as height, leaf area, and biomass. Indeed, under CHT conditions, N-CDs significantly reduced the contents of malondialdehyde, superoxide, and hydrogen peroxide. In contrast, N-CDs significantly increased the activities of superoxide dismutase, peroxidases, catalase, and ascorbate peroxidase to 117.57%, 158.53%, 162.79%, and 152.23%, respectively. Notably, N-CDs dramatically changed the glutathione pool for tomato detoxification. Overall, this study synthesized the non-cytotoxic N-CDs that not only promote tomato growth but also alleviate CHT toxicity by strengthening the tomato’s antioxidant defense system. Full article

Capão da Roça, located in the municipality of Charqueadas, is one of the few areas of coal tailing deposits at the surface within the State of Rio Grande do Sul, Brazil that generates acid mine drainage (AMD). Over the course of 2007, the landfill was characterised in detail, and an active treatment plant involving pH neutralisation and metal precipitation operations was implemented to meet emission standards for mine water. In that year, based on the sulphur mass balance, it was estimated that the process of AMD generation would last for approximately two decades. The objective of this work was to study the temporal evolution of the parameters of the raw AMD. The effluent was analysed for 17 years on a monthly basis in regard to pH, acidity, metals (Fe, Al, and Mn), and sulphates. The results indicated an increase in pH (from 2.1 to 4.7), a decay in the concentration of metals (from 177.8 to 0.1 mg L⁻¹ for iron, 29.0 to 0.1 mg L⁻¹ for aluminium, and 3.1 to 0.6 mg L⁻¹ for manganese), sulphates (from 2023 to 307 mg L⁻¹), and acidity (from 539.5 mg CaCO₃ L⁻¹ to 3.96 mg CaCO₃ L⁻¹), which were adjusted to a first-order kinetic model in agreement with observations at some other mining sites. Over the years, the active lime neutralisation–precipitation treatment system has been efficient in treating the effluent. Today, most water quality parameters already meet emissions standards; however, the AMD treatment plant is still necessary to prevent pH fluctuations and to reduce the concentrations of manganese. For this reason, a transition from an active to a passive treatment system was considered. Pilot scale studies confirmed that channels filled with gravel-size limestone or slag enable the neutralisation/increase in the pH of the effluent and remove residual amounts of some metals, resulting in an effluent with no level of toxicity to the microcrustacean Daphnia magna. Full article

The production of apples plays a crucial role in global agriculture. In 2023, the world production of these fruits amounted to nearly 150 million tonnes, cultivated on 6.6 million ha. Today’s horticulture faces the difficult challenge of maintaining high productivity while simultaneously reducing negative environmental impact. Traditional methods based on chemical pesticides encounter increasing problems, such as biodiversity loss, toxic residues in food, development of pest resistance, and disrupted balance of ecosystems. Integrated Pest Management (IPM) responds to these challenges by combining biological and agrotechnical methods with selective use of chemicals. Biopesticides are a crucial component of IPM, and they include antagonist microorganisms, substances of natural origin, and other biological methods of control, which represent effective alternatives to conventional measures. Their development is driven by consumer requirements concerning food safety, as well as by the need to protect the environment. The aim of this article is to highlight current problems in apple production, describe microorganisms and natural substances used as biopesticides used for the protection of apple orchards, as well as present the characteristics of modern technologies used for biocontrol in apple orchards. Full article

Sugarcane is a key crop for sugar, biofuels, and bioenergy, with Brazil as the world’s largest producer. Intensive cultivation demands pesticides like tebuthiuron and thiamethoxam, while fertigation with vinasse may alter their environmental behavior. Sustainable approaches, such as phytoremediation, are needed to mitigate negative impacts on soil quality. This study assessed the phytoremediation potential of Canavalia ensiformis and Mucuna pruriens in soils contaminated with tebuthiuron, thiamethoxam, and vinasse under greenhouse conditions. Experiments used a completely randomized design (five replicates, 4 × 2 factorial). Plant development impacts on the sentinel species Crotalaria juncea, and ecotoxicity via Lactuca sativa bioassays were evaluated. Tebuthiuron strongly inhibited C. ensiformis, while thiamethoxam showed mild stimulatory effects. M. pruriens maintained better growth in the presence of contaminants. Bioassays revealed greater residual toxicity in tebuthiuron treatments. Overall, M. pruriens demonstrated superior biomass production and capacity to lessen soil toxicity, underscoring its potential as a sustainable tool for phytoremediation of pesticide-impacted soils. Full article

The aim of our study was to make one step further to verify a method that can turn back mycotoxin-contaminated crops into the circular economy. Thus, the possibility of utilizing aflatoxin B1 (AfB1)-contaminated corn by yellow mealworms (Tenebrio molitor) was investigated to be used as fish feed components. Four different self-contaminated corn samples were used in our study, of which one was below and three were above the threshold limit (20 µg/kg) regulated by the European Union. The highest applied AfB1 concentration in our study for insect feeding was 415 µg/kg (more than twenty times higher than the threshold). After a five-week feeding period insect mortality was not increased, even in the highly contaminated group, compared to the negative control. The mycotoxin in the dried and ground insects was only detected in the case of feeding with the highest-concentration corn, however it remained as low as 2.2 µg/kg. For studying the possible physiology effects, insect grounds were used in feeding experiments of common carp (Cyprinus carpio) fries. Results showed that insect meal, even if originated from a highly mycotoxin-contaminated crop, did not have a significant effect on the examined fish fries, compared with the control groups. The AfB1 concentrations of the leftover frass after insect rearing were also measured, and in the case of the highest concentration mealworm group, it was 157.6 µg/kg (other groups were under 20 µg/kg). Toxicity of frass extracts from different contaminated groups was also studied using microinjected zebrafish (Danio rerio) embryos. Extracts of the highly contaminated frass samples caused 91.67 ± 3.33% mortality and led to numerous phenotypic changes, which highlights the need for responsible usage of the by-product. However, the effects of injected frass samples, originating from corn with lower and more environmentally relevant AfB1 concentrations, were significantly lower. Full article