Evaluation of phytotoxicity and cytotoxicity of industrial catalyst components (Fe, Cu, Ni, Rh and Pd): A case of lethal toxicity of a rhodium salt in terrestrial plants

Antibacterial performance of nanosecond laser irradiated zirconium-based bulk metallic glass

Bulk metallic glasses (BMGs) have garnered significant attention in recent decades due to the outstanding physical, chemical, and biomedical characteristics. The biomedical application of metallic glass also received extensive attention. This report investigates the interplay among antibacterial performance, crystallization and processing parameters of Zr-based bulk metallic glass (Zr-BMG) following nanosecond laser irradiation. We examined surface morphology, crystallization behavior, surface quality, binding energy, and ion release properties post-laser irradiation. Additionally, we evaluated the generation of reactive oxygen species upon immersion of Zr-BMG in phosphate-buffered saline using the 2',7'-dichlorofluorescin diacetate method. Staphylococcus aureus was chosen to assess Zr-BMG's antibacterial performance, while mouse osteoblasts were utilized to investigate in vitro cytotoxicity. Our findings revealed that at laser energy intensities below 0.08 J/mm2, the amorphous structure of Zr-BMG remained intact after irradiation. Moreover, laser irradiation significantly enhanced the antibacterial performance of Zr-BMG. The release rate of ion, concentration of reactive oxygen species, and antibacterial properties exhibited direct proportionality to laser energy intensity. However, surfaces exhibiting high antibacterial efficacy also displayed elevated cytotoxicity. The surface irradiated with a 7 μJ ablation pulse and 200 mm/s irradiation speed demonstrated a superior balance between antibacterial and cytotoxic properties while maintaining an amorphous state. We hope this research can provide theoretical reference and data support for the application of metallic glass in biomedical application.

Emerging contaminants and their potential impacts on estuarine ecosystems: Are we aware of it?

Emerging contaminants (ECs) are becoming more prevalent in estuaries and constitute a danger to both human health and ecosystems. These pollutants can infiltrate the ecosystem and spread throughout the food chain. Because of the diversified sources and extensive human activities, estuaries are particularly susceptible to increased pollution levels. A thorough review on recent ECs (platinum group elements, pharmaceuticals and personal care products, pesticides, siloxanes, liquid crystal monomers, cationic surfactant, antibiotic resistance genes, and microplastics) in estuaries, including their incidence, detection levels, and toxic effects, was performed. The inclusion of studies from different regions highlights the global nature of this issue, with each location having its unique set of contaminants. The diverse range of contaminants detected in estuary samples worldwide underscores the intricacy of ECs. A significant drawback is the scarcity of research on the toxic mechanisms of ECs on estuarine organisms, the prospect of unidentified ECs, warrant research scopes.

A comparative study of the physiological and biochemical properties of tomato (Lycopersicon esculentum M.) and maize (Zea mays L.) under palladium stress

There is great concern about the environmental impact and toxicity of palladium (Pd) because of its widespread use in automotive catalytic converters and other applications. Pd migrates and transforms in the environment and is absorbed by plant roots where it affects plant growth and eventually enters the food chain. Here we explored the effects of Pd on the physicochemical and biochemical characteristics of C3 (tomato) and C4 (maize) plants. We measured physicochemical and biochemical properties, including chlorophyll, protein, soluble sugar, antioxidant enzymes, malondialdehyde, proline, and root activity, in tomato and maize seedlings after cultivation in different concentrations of PdCl₂ solution (0, 0.2, 0.5, and 1 mM) in order to observe how Pd stresses them. Results showed that, with increasing Pd concentration, chlorophyll a and chlorophyll b contents and root activity decreased. Meanwhile, malondialdehyde, proline, protein, and soluble sugar contents increased. After cultivation in 1 mM PdCl₂, the Pd contents in the roots, stems, and leaves of tomato seedlings were 12.389, 1.132, and 0.206 mg/g, respectively. In general, Pd has significant effects on the physiological and biochemical properties of both tomato and maize. Additionally, tomato seedlings were more sensitive to Pd stress, photosynthesis in maize was less inhibited by Pd and the antioxidant capability of maize was stronger. These results indicated that maize (C4 plant) exhibited a higher tolerance to Pd than tomato (C3 plant). Pd migration in tomato was observed and the translocation factor (TF) was calculated. The values of TF_stem/root, TF_leaf/root, TF_leaf/stem, and TF_shoot/root were 0.09, 0.02, 0.18, and 0.11 in tomato seedlings, respectively. Pd accumulated most in the roots, followed in turn by stems, leaves, and only trace amount of Pd was transferred into shoots.