Immunotoxicity of stainless-steel nanoparticles obtained after 3D printing.

This study aims to investigate the in vitro effects of nanoparticles (NPs) produced during the selective laser melting (SLM) of 316 L stainless steel metal powder on the immune response in a human blood model. Experimental data did not reveal effect on viability of 316 L NPs for the tested doses. Functional immune assays showed a significant immunosuppressive effect of NPs. There was moderate stimulation (117%) of monocyte phagocytic activity without significant changes in phagocytic activity and respiratory burst of granulocytes. A significant dose-dependent increase in the levels of the pro-inflammatory cytokine TNF-a was found in blood cultures treated with NPs. On the contrary, IL-8 chemokine levels were significantly suppressed. The levels of the pro-inflammatory cytokine IL-6 were reduced by only a single concentration of NPs. These new findings can minimise potential health risks and indicate the need for more research in this area.

Simple method for quantification of metal-based particles in biopsy samples of patients with long bone implants - Pilot study.

The presence of particles fixed in tissue samples due to implant degradation or disintegration plays an important role in post-operative complications. The ability to determine the size, shape, chemical composition and, above all, the number of these particles can be used in many areas of medicine. This study presents a novel, simple metal-based particle detection method using scanning electron microscopy with energy dispersive spectrometer (SEM-EDS). The presence of metal particles in biopsy specimens from long bone nail-fixated implants (10 patients with titanium steel nails and 10 patients with stainless steel nails) was studied. The samples were analysed using automated area analysis based on image binarization and brightness to 255 grayscale. The results were supplemented with histological data and statistically analysed. The method based on the software used was found to be accurate and easy to use and, thus, appears to be very suitable for particle detection in similar samples.

Disparities in Methods Used to Determine Microplastics in the Aquatic Environment: A Review of Legislation, Sampling Process and Instrumental Analysis.

Plastic particles smaller than 5 mm, i.e., microplastics, have been detected in a number of environments. The number of studies on microplastics in marine environments, fresh water, wastewater, the atmosphere, and the human body are increasing along with a rise in the amounts of plastic materials introduced into the environment every year, all contributing to a range of health and environmental issues. Although the use of primary microplastics has been gradually reduced by recent legislation in many countries, new knowledge and data on these problems are needed to understand the overall lifecycle of secondary microplastics in particular. The aim of this review is to provide unified information on the pathways of microplastics into the environment, their degradation, and related legislation, with a special focus on the methods of their sampling, determination, and instrumental analysis. To deal with the health and environmental issues associated with the abundance of microplastics in the environment, researchers should focus on agreeing on a uniform methodology to determine the gravity of the problem through obtaining comparable data, thus leading to new and stricter legislation enforcing more sustainable plastic production and recycling, and hopefully contributing to reversing the trend of high amounts of microplastics worldwide.

Influence of Nano-ZnO Exposure to Plants on L-Ascorbic Acid Levels: Indication of Nanoparticle-Induced Oxidative Stress.

With the continuously growing production of nanomaterials, their presence in the environment increases. The effects of nanoparticle exposure on plants are yet not fully understood. This study aimed to provide new insights into the stress induced by the exposure of plants to nanoparticles via the determination of the content of L-ascorbic acid, known antioxidant, in the samples of bryophyte species Pleurozium schreberi (Brid.) Mitt. Bryophyte samples, collected from a pristine environment, were exposed to 0.1 g·L-1 suspensions of nano-ZnO for five weeks. Prior to the exposure, the samples were subjected to the combination of treatments-washing or not washing as well as drying or irrigation. In order to assess the level of oxidative stress caused by the exposure to the ZnO nanoparticles under various pre-treatment conditions, the content of the L-ascorbic acid in the samples was determined by titration with dichlorophenolindophenol. Effect of both nano-ZnO exposure and pre-treatment was observed; nano-ZnO exposure significantly reduced the content of L-ascorbic acid in the bryophyte samples indicating it being consumed in the repair processes following the exposure-related physiological stress.