ABSTRACT Guano samples were collected from nine bat roosts across Bosnia and Herzegovina (caves, tunnels and an abandoned underground quarry) between August 2021 and November 2022. Samples originated from colonies of both sedentary and migratory species. Concentrations of potentially toxic elements (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were analysed using flame atomic absorption spectrometry (FAAS). A composite PTI (based on normalised Cd, Cu, Pb and Zn) was calculated to support spatial screening, and KDE mapping was used to visualise the clustering of higher-index sites. Two sites showed evidence of direct anthropogenic pressure, while several others may have been indirectly influenced. Sites associated with anthropogenic activities were compared with those outside apparent pollution sources. The highest concentrations were observed for Fe, Zn, Mn and Cu. Marked interspecific differences at the same site suggest that migratory behaviour and roosting habits may modulate exposure to pollutants. This pilot study provides baseline data for Bosnia and Herzegovina and supports the use of bat guano as a non-invasive biomonitoring matrix for PTE contamination.

Heavy metals are persistent environmental pollutants with well-documented toxic, genotoxic, and bioaccumulative effects across ecosystems. This study evaluates blood cell morphology as a potential biomarker of environmental pollution in Miniopterus schreibersii (Kuhl, 1819), a migratory bat species. Individuals were captured from a contaminated site (Dardagani underground quarry) and a reference site (Mokra Megara Cave) in Bosnia and Herzegovina. Environmental sampling included guano, soil, and water. Guano was analyzed for nine heavy metals (Cr, Cu, Mn, Fe, Co, Ni, Cd, Pb, Zn) to assess site-specific contamination. Distinct spatial differences in metal accumulation were observed. Elevated Cu and Mn concentrations in guano from the contaminated site indicated anthropogenic input, whereas higher Fe, Ni, and Pb at the reference site reflected natural lithogenic enrichment. Hematological and cytological examinations revealed morphological alterations in blood cells of bats from the contaminated site, including neutrophil hypersegmentation, polychromatophilia, atypical granulation, and nuclear abnormalities in lymphocytes. The total lymphocyte count differed significantly, and these qualitative changes suggest early physiological adjustments or potential indicators of sublethal toxic exposure. By integrating environmental (soil and guano) and biological (blood morphology) parameters, this study demonstrates a non-lethal and ecologically relevant approach to biomonitoring. Blood cell alterations, combined with metal analyses in guano, provide a sensitive tool for detecting potential chronic environmental stress. M. schreibersii is reaffirmed as a valuable sentinel species for ecological monitoring in karst and other vulnerable habitats; however, the limited number of high-quality blood smears obtainable under field conditions still remains a constraint to broader generalization of the findings.

A novel heterobimetallic ruthenium(II)–gold(I) complex featuring a bridging bis(diphenylphosphino)butane (dppb) ligand was prepared and fully characterized. Single-crystal X-ray diffraction revealed a piano-stool geometry around Ru(II) with η6-cymene, two chlorido ligands, and one phosphorus atom from dppb, while the Au(I) center adopts a linear P–Au–Cl coordination. Structural integrity in the solution was confirmed by 1D and 2D NMR spectroscopy, while solution behavior was further monitored by variable solvent 31P NMR and UV/Vis spectroscopy, indicating that the organometallic Ru–arene core remains intact, whereas the chlorido ligands coordinated to Ru exhibit partial lability. Complementary characterization included elemental analysis, FTIR, and UV/Vis spectroscopy. Spectrofluorimetric and FRET analyses showed that Au(dppb), Ru(dppb), and the heterobimetallic AuRu complex bind to BSA with apparent constants of 1.41 × 105, 5.12 × 102, and 2.66 × 104 M−1, respectively, following a static quenching mechanism. In vivo biological evaluation in Wistar rats revealed no significant hepatotoxicity or nephrotoxicity, with only mild and reversible histological alterations and preserved hepatocyte nuclear morphology. Hematological analysis indicated a statistically significant reduction in leukocyte populations, suggesting immunomodulatory potential, while elevated serum glucose levels point to possible endocrine or metabolic activity. These findings highlight compound structural stability and intriguing bioactivity profile, making it a promising platform for further organometallic drug development and testing.

Summary The rapid rise of 3D printing, both in industrial and home settings, presents emerging health and environmental risks. While 3D printing enhances sustainability by reducing waste and optimizing resource use, its impact on human health remains poorly understood. The use of metals and polymers linked to health risks, coupled with the release of inhalable particles and volatile organic compounds, raises concerns about respiratory and systemic effects. The absence of clear guidelines creates high public demand for information and limits safe implementation, particularly in schools and homes where millions of 3D printers are expected by 2030. Additionally, improper disposal of 3D printing polymer materials may exacerbate plastic pollution. This article proposes the perspective of a structured risk assessment framework set on particle emissions from industrial 3D printing. It will offer a practical tool to bridge current knowledge gaps and to inform safe practice and policy development, because immediate action is necessary to balance innovation with safety.

The environmental fragmentation of plastics generates a mixture of plastic particles of various sizes, which frequently co-occur with other mobile and persistent environmental pollutants. Despite the prevalence of such scenarios, the interaction between micro- and nanoplastics (MNPs) and their combined effects with environmental pollutants, such as highly toxic hexavalent chromium (Cr(VI)), remain almost entirely unexplored in mammalian species. This study demonstrated that nanoplastic and microplastic particles co-aggregate and together influence Cr bioaccumulation patterns and related physiological alterations in rats. Following a four-week repeated intragastric exposure of Wistar rats to MNPs and Cr(VI), either alone or in combination, MNPs significantly enhanced Cr bioaccumulation in the liver, heart, brain, and skin. Under co-exposure conditions, Cr(VI) was the primary driver of cellular effects observed in the blood, including shifts in immune cell subpopulations (e.g., neutrophils, lymphocytes) and alterations in red blood cell indices, while serum biochemistry reflected limited physiological stress. MNPs per se decreased creatine kinase activity and increased cholesterol levels. In summary, polystyrene MNPs increase Cr(VI) distribution and bioavailability, but co-exposure does not uniformly exacerbate toxicity. Instead, their interaction may selectively alter physiological responses, emphasizing the need for a deeper understanding of their combined effects and potential health risks.

Background/Aim. Rheumatoid arthritis (RA) is a systemic autoimmune disease that can cause destructive joint disease and progressive disability. The diagnosis of RA is based on laboratory and clinical evidence, which includes the analysis of inflammatory markers, hematological, and biochemical parameters. Methods. Fifty patients diagnosed with RA without methotrexate (MTX) therapy and 50 patients with therapy (MTX, 7.5 mg/week; after three months prednisolone 10 mg/day) were included in this study. After six months of therapy, inflammatory biomarkers, hematological, and biochemical parameters were analyzed. Results. Inflammatory biomarkers: sedimentation rate (SE), C-reactive protein (CRP), and anti-cyclic citrullinated peptide (anti-CCP) are significantly lower in the group of patients on therapy compared to patients without MTX therapy. Significant differences were not found for the rheumatoid factor (RF). Significant differences were not found for hematological parameters between the compared groups. Analysis of serum biochemical parameters showed significant differences for aspartate aminotransferase (AST) and iron values. In patients without MTX therapy, the incidence of anemia was recorded in 68%, which is significantly higher than the incidence of 32% in patients with therapy. Conclusion. Prescribed therapy has shown effectiveness in the treatment of RA and reduction of the inflammatory process. The success of the treatment depends on the timely diagnosis of RA. Postponement of therapy and late-detected disease prolongs therapy treatment and often requires a combination of several drugs.