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Biodegradable polymer materials are increasingly used in the packaging industry due to their good properties and low environmental impact. Therefore, the work was performed on the injection molding of the bio-based composites of polylactide (PLA) and polyhydroxyalcanates (PHI) modified with two phases: reinforcing (walnut shell flour and cellulose) and coloring (beta carotene and anthocyanin). The produced materials were subjected to wide mechanical characteristics—tensile, flexural, and fatigue tests. Additionally, the influence of photo and hydrodegradation on the change of the surface structure and mechanical properties of the composites was assessed. The addition of natural fillers contributed to the improvement of the stiffness of the tested composites. PHI composites withstood a higher number of cycles during cyclic loading, but the stress values obtained in the static tensile test were higher for PLA composites. Moreover, a clear change of color was observed after both the photo and hydrodegradation process for all tested materials; however, after the degradation processes, the filler-modified materials underwent greater discoloration. For the composites based on PHI, the type of degradation did not affect the mechanical properties. On the other hand, for PLA composites, hydrolytic degradation contributed to a higher decrease in properties—the decrease in tensile strength for unmodified PLA after photodegradation was 4%, while after hydrodegradation it was 24%.

Flubendazole (FLU) and fenbendazole (FEN) belong to benzimidazoles-pharmaceuticals widely used in veterinary and human medicine for the treatment of intestinal parasites as well as for the treatment of systemic worm infections. In recent years, usage of these drugs increased, which resulted in a larger contamination of the environment and possible negative effects on biota. Hence, in our research, we investigated an aquatic ecotoxicity of these pharmaceuticals towards: marine bacteria ( Vibrio fischeri), green algae ( Scenedesmus vacuolatus), duckweed ( Lemna minor) and crustacean ( Daphnia magna). Ecotoxicity tests were combined with chemical analysis in order to investigate the actual exposure concentration of the compounds used in the experiment as well as to stability and adsorption studies. As a result, study evaluating sensitivity of different aquatic organisms to these compounds and new ecotoxicological data is presented. The strongest negative impact of FLU and FEN was observed to D. magna. [ABSTRACT FROM AUTHOR]

The glycoalkaloid, sterol and fatty acid contents were determined in raw and blanched leaves of the gboma eggplant (Solanum macrocarpon L.). The results of the study revealed that 5 min blanching was sufficient to obtain a 35-56% decrease in the glycoalkaloid content in leaves to values below 200 mg⋅kg-1 of fresh weight, which is regarded as a safe level in foods. Processing also significantly decreased the free fatty acid content and increased the free sterol content. In raw and blanched leaves, however, the contents of total fatty acids and sterols were comparable. The total sterol content in S. macrocarpon leaves was as high as 3.2-4.0 g⋅kg-1 of dry weight, while the total fatty acid content was 23.0-32.1 g⋅kg-1 of dry weight. The cholesterol contribution to total sterols did not exceed 10%. While saturated compounds were most abundant in the free fatty acid fraction, total fatty acids were dominated by C18 polyunsaturated compounds. Additionally, isomerization of unsaturated fatty acids during hydrolysis and silylation of lipids from dried plant material was demonstrated. The presence of artefacts did not affect the results of quantitative analysis. [ABSTRACT FROM AUTHOR]

The main goal of this study is the examination of polypropylene (PP) microplastics (MPs) as possible carriers of daily use pharmaceutical compounds. The selected compounds can be separated into three groups: (i) antibiotics (Trimethoprim, Metronidazole, Indomethacin, Isoniazid), (ii) anti-inflammatories (Ketoprofen, Diclofenac), and (iii) anti-hypertensive (Valsartan). Two types of PP MPs (virgin and UV-aged) were used in the experimental procedure, and the effect of time and the effect of the initial concentrations of the drugs were examined. The impact of various environmental factors such as pH, salinity, and natural organic matter were also explored. The last two factors were studied using real aqueous matrices such as wastewater and seawater. According to the obtained results, the highest uptake was observed in indomethacin (9.3 mg/g) and diclofenac (7.3 mg/g), owing to their physiochemical properties. Aged particles showed enhanced adsorption ability in accordance with the existing literature, as their adsorption capacity was between 0.5–1.5 times greater than that of the virgin ones. Regarding the desorption of compounds from the virgin and aged PP MPs at three different pH values, diclofenac and indomethacin exhibited the highest desorption capacity, while alkaline conditions favored the desorption ability of PP MPs for most of the target compounds. [ABSTRACT FROM AUTHOR]

Plastics and antibiotics are two classes of emerging contaminants with proposed negative impacts on aqueous ecosystems. In this paper, the adsorption of Ciprofloxacin (CIP) from water in studies using plastic-based adsorbents over the last half-decade was reviewed. The objectives of this review were to 1) review the procedures in the development of plastic-based material for CIP removal; 2) review the experimental designs adopted for CIP removal by plastic-based material; 3) summarise the factors affecting the CIP adsorption behaviour of plastic-based material; 4) explore the primary mechanism by which plastic-based material adsorb CIP; 5) evaluate the reusability of the plastic-based materials and 6) identify deficiencies in existing research on the adsorption of CIP by plastic-based materials and give suggestions for further study. We observed that mainly four categories of materials have been used including native plastic-based adsorbents, chemically modified plastic-based adsorbents, high-energy physical treated plastic-based adsorbents, and plastic-based composite adsorbents. The highest removal rate was recorded for the composite (99.1%). Experimental designs are mainly batch while columns have been scantly used. Changes in the pH, contact time, initial concentration, temperature, and ionic strength also affect the adsorption capacity. The most common mechanism by which CIP was adsorbed is hydrogen bonding. Additionally, electrostatic interaction and other non-covalent forces, such as polar-polar interaction, halogen bonds, and π–π interactions, are also mechanisms. The majority of current research on plastic-based material adsorption behaviour is done in labs, with little in-depth investigations of the adsorption process and affecting variables. As a result, further research on the adsorption behaviour of plastic-based materials in the environment is needed, which will help to fill that gap. [ABSTRACT FROM AUTHOR]

To evaluate the water quality in the Poprad, Kamienica, Dunajec river and the Łubinka stream in the Sącz agglomeration, two series of pilot studies were conducted on raw water samples, with a particular focus on both physical parameters (such as total suspended matter, turbidity, pH, and conductivity) and chemical parameters. The analysis presented increased concentrations of phosphorus, nitrogen, BOD5, COD, chlorides, sulfates, permanganate value, orthophosphates, total suspended matter, specific electrolytic conductivity (PEW), pH levels, and various elements including lithium, magnesium, manganese, potassium, sodium, calcium, and iron. No exceedance of the detection limits for individual pesticides were observed in the waters of the Poprad, Kamienica rivers and the Łubinka stream. Nevertheless, increased concentrations of the insecticide imidacloprid and the fungicide imazalil were detected in the Dunajec river. The primary factors impacting water quality in the Sącz agglomeration are the use of fertilizers, the proximity of wastewater treatment plants, and the presence of landfill sites. [ABSTRACT FROM AUTHOR]

Among the various compounds regarded as emerging contaminants (ECs), pharmaceuticals and personal care products (PPCPs) are of particular concern. Their continuous release into the environment has a negative global impact on human life. This review summarizes the sources, occurrence, persistence, consequences of exposure, and toxicity of PPCPs, and evaluates the various analytical methods used in the identification and quantification of PPCPs in a variety of solid and liquid environmental matrices. The current techniques of choice for the analysis of PPCPs are state-of-the-art liquid chromatography coupled to mass spectrometry (LC-MS) or tandem mass spectrometry (LC-MS2). However, the complexity of the environmental matrices and the trace levels of micropollutants necessitate the use of advanced sample treatments before these instrumental analyses. Solid-phase extraction (SPE) with different sorbents is now the predominant method used for the extraction of PPCPs from environmental samples. This review also addresses the ongoing analytical method challenges, including sample clean-up and matrix effects, focusing on the occurrence, sample preparation, and analytical methods presently available for the determination of environmental residues of PPCPs. Continuous development of innovative analytical methods is essential for overcoming existing limitations and ensuring the consistency and diversity of analytical methods used in investigations of environmental multi-class compounds. [ABSTRACT FROM AUTHOR]

Antibiotics present a pressing environmental challenge as emerging pollutants due to their persistence and role in promoting antibiotic-resistant bacteria. To model the utilization of Ganoderma lucidum GlLCC1 laccase in degrading antibiotics, a 3D homology model of GILCC1, based on Lentinus tigrinus mushroom laccase, was utilized. Five broad-spectrum WHO-designated antibiotics with molecular weights between 100 and 500 Da were selected. Molecular dynamics simulations were conducted at pH 3.0 and 7.0 to evaluate the interactions between GILCC1 and antibiotics in a TIP3P water box, with system behaviour assessed at 300 °K using an NPT assembly. ABTS (2,2ʹ-Azino-bis (3-ethylbenzthiazoline-6-sulfonic Acid)) served as the comparison molecule. The binding free energy indicated a strong affinity between 3D GILCC1 and various ligands. At pH 3.0, GILCC1 exhibited significant Gibbs free energy (ΔG), indicating a high affinity for Levofloxacin (LVX; −8.2 kcal mol−1), Sulfisoxazole (SFX; −7.8 kcal mol−1), Cefuroxime (CXM; −7.5 kcal mol−1), Cephradine (CFD; −7. 5 kcal mol−1), ABTS (−7.6 kcal mol−1), and Tetracycline (TE; −7.5 kcal mol−1), attributed to pocket topology and interactions such as hydrogen bonds and van der Waals forces. Electron transfer in GILCC1 involved a chain of residues, including His395 and Phe239. Although the affinity decreased at pH 7.0, the potential of GILCC1 to degrade antibiotics remained plausible. This study accurately predicted the behaviour of the laccase-antibiotic system, providing atomic-level insights into molecular interactions and emphasizing the importance of experimental assays and assessments of antibiotic degradation in wastewater, considering various chemical compounds. The use of ABTS as a mediator was suggested to enhance molecule affinity.Article highlights: We predicted the chemical interaction between laccase (GILCC1) and commonly used animal and human antibiotics. This study provides novel insight into the degradation of antibiotics, commonly found in wastewater from hospitals, households and pharmaceutical industries. These results open and indirect the doors to the future developing of a new strategy against the proliferation of antibiotic resistance. [ABSTRACT FROM AUTHOR]

Owing to the presence of drugs targeting adrenergic receptors in aquatic ecosystems, considerable attention has been directed towards their environmental distribution and fate in recent decades. However, their potential impacts on non-target aquatic organisms, particularly fish, have received relatively limited investigation. In this study, moxisylyte (MOX) and propranolol (PRO) were selected as representatives of α- or β-adrenergic receptor antagonist, respectively, and we assessed their effects on the early life stages of zebrafish, especially on the nervous and cardiovascular systems. Although both compounds exhibited marginal effects on zebrafish survival, hatching and gross abnormality following exposure to concentrations ranging from 1 to 625 μg/L, they adversely affected the development of cardiovascular and nervous systems, but through different mechanisms of action, as evidenced by variations in gene transcriptional responses and enzyme activities. Notably, cardiovascular responses appear promising for use as potential biomarkers for exposure to drugs targeting adrenergic receptors. This study enhances our understanding of the ecotoxicological risks posed by α- and β-blockers in fish. Nonetheless, further investigation is needed to elucidate the precise mechanisms underlying the impacts of drugs targeting adrenergic receptors due to our limited knowledge of the physiological functions of the adrenergic system in fish. [ABSTRACT FROM AUTHOR]

Context: Pollution by synthetic polymers is even more problematic to the environment when this material is fragmented into small portions, forming microplastics (MPs). Aims: We analysed the influence of the Brazilian Carnival on the abundance and richness of MPs in the Paraíba do Sul River (PSR). Specific objectives included classifying MPs by shape, colour and polymer, and quantifying and comparing the abundance and richness of surface-water MPs before, during and after Carnival. Methods: Samples were taken from the superficial layer of the water column in 2023, by using manta net. Key results: In total, 843 MPs were identified in the surface water of PSR. Higher MP concentrations were observed after the Carnival event than in the other two periods. Blue and black fibres were the predominant MPs. Glitter and sequin occurred only during the Carnival and post-Carnival periods. Polyester, polyamide and polyethylene were the most abundant in all the periods. Conclusions: Our findings strongly indicated that Carnival represents a potential short-term source of MP introduction into the PSR basin. Implications: A significant 170% increase in MP abundance was observed 10 days after the Carnival, which is an event occurring across multiple locations in the PSR basin. We conducted a microplastics survey in a stretch of the Paraíba do Sul River basin, the water system of which flows through the most populous area in Brazil. Samples were taken from the superficial layer of the water column during the Carnival period in 2023. Higher microplastic concentrations were observed after the Carnival event than in the pre- and during-Carnival periods. [ABSTRACT FROM AUTHOR]