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.

Microplastics and additives in patients with preterm birth: The first evidence of their presence in both human amniotic fluid and placenta.

Considering the well documented, almost ubiquitous nature of microplastics in different environments, the exposure of pregnant women to microplastics may pose risks to the unborn children. The study focused on investigating the presence of microplastics in amniotic fluid and placenta, and brings the first evidence of the simultaneous presence of microplastics and additives in both human amniotic fluid and placentas. In total, 20 samples of amniotic fluid and placenta from 10 patients were analyzed for the presence of microplastics and plastic additives by Fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) after alkaline digestion with KOH. In 9 out of 10 patients, microplastics or additives were found in amniotic fluid, placenta, or both. Specifically, 44 particles of microplastics and polymer additives were identified in all samples. Chlorinated Polyethylene (CPE) and Calcium zinc PVC Stabilizer with particle sizes between 10 and 50 µm prevailed. Although all women involved in this study, who provided placenta and amniotic fluid samples, experienced physiological, singleton pregnancies complicated with preterm prelabour rupture of membranes (PPROM), it is too early to draw any conclusions and more research is needed.

The first evidence of microplastic occurrence in mine water: The largest black coal mining area in the Czech Republic.

Climate change is creating new challenges for water supply worldwide, making the search for new sources of water vital. As mine water could serve as a potential source, this study investigated the presence of microplastics in water from terminated deep mines in the largest coal basin in the Czech Republic, as well as in water from nearby shallow wells. The particles found were analyzed for size, polymer composition, color and morphology using the ImageJ tool, infrared spectroscopy with Fourier transform (FTIR) and an optical stereomicroscope with a digital camera. Microplastics were detected in all tested sites. Their range accounted for 2.5-17.5 items/L for mine water samples and 2.5-20 items/L for well samples, with fibers being the dominant type. The average width of particles from mine water and wells amounted to 58 µm; 71 µm, length to 655 µm; 501 µm and area to 22,067 µm2; 28,613 µm2, respectively. Blue color was prevalent, among materials, in both cases, plastic coated paper was found dominant to Polyethylene terephthalate (PET), Polyester (PES), Tetrafluoroethylene-perfluoro (Propyl Vinyl Ether) - Copolymer (TFE-PPVE), and polypropylene (PP). The research provides the first evidence of microplastics' presence in underground waters from deep mines and shallow wells in the same area. The data suggest that it is almost impossible to find underground water sources free of microplastic contamination. In this context, atmospheric contamination from mine ventilation and infiltration through terminated mines were identified as potential sources, while infiltration through soil and rock formations is unlikely given the geological composition. The results of this study can serve as a relevant basis for further research on microplastics in mine waters. Additionally, the conclusions can advance the development in remediation technologies of microplastics from deep underground waters and their implementation in practice, particularly in light of upcoming legislation.

Immunohistochemical evaluation of tissues following bone implant extraction from upper and lower limb.

Fractured bones can regenerate and restore their biological and mechanical properties to the state prior to the damage. In some cases, however, the treatment of fractures requires the use of supportive implants. For bone healing, three processes are essential: the inflammatory phase, the repair phase and the remodelling phase. A proper course of the first - inflammatory - stage is important to ensure a successful fracture healing process. In our study, we evaluated tissue samples immunohistochemically from the area surrounding the fractures of upper and lower limbs (bone tissue, soft tissue, and the implant-adhering tissue) for markers: CD11b, CD15, CD34, CD44, CD68, Cathepsin K, and TRAcP that are linked to the aforementioned phases. In soft tissue, higher expressions of CD68, CD34, CD15 and CD11b markers were observed than in other locations. TRAcP and Cathepsin K markers were more expressed in the bone tissue, while pigmentation, necrosis and calcification were more observed in the implant-adhering tissue. Since even the implant materials commonly perceived as inert elicit the observed inflammatory responses, new surface treatments and materials need to be developed.

Electrochemical, Biological, and Technological Properties of Anodized Titanium for Color Coded Implants.

Anodization coloring of titanium tools or implants is one of the common methods for the differentiation of each application by its size or type. Commercial purity titanium grade 4 plates (50 × 20 × 0.1 mm) were tested to obtain their electrochemical and other technological properties. The coloring process was done using the potential of 15, 30, 45, 60, and 75 Volts for 5 s in 1 wt. % citric acid in demineralized water solution. Organic acids solutions generally produce better surface quality compared to inorganic acids. The contact angle of colored surfaces was measured by the sessile drop method. Electrochemical impedance spectroscopy and potentiodynamic polarization were used for the determination of selected electrochemical and corrosion parameters of the tested surfaces. It was found that the anodization process decreases corrosion potential significantly. It was also confirmed that a higher potential used for anodization results in higher polarization resistance but also a decrease in corrosion potential. The anodization process at 75 V produces surfaces with the lowest corrosion rate under 1 nm/year and the noblest corrosion potential. It was confirmed that the anodization process in citric acid does not affect titanium cytotoxicity.

Solid Anorganic Particles and Chronic Rhinosinusitis: A Histopathology Study.

Although extensive research has shown the pathological effect of fine and ultrafine airborne particles, clear evidence of association of environmental exposure to them and inflammatory changes in human nasal mucosa is missing. Meanwhile, pathogenesis of chronic rhinosinusitis, despite being a disease with high prevalence in the population, is still unclear. The increasing evidence of the pro-inflammatory properties of these particles raises the question of their possible role in chronic rhinosinusitis. The presented study focused on detection of microsized anorganic particles and clusters of nanosized anorganic particles in the nasal mucosa of patients with chronic rhinosinusitis by Raman microspectroscopy and comparison of their composition to histologic findings. The results were compared to the findings in mucosa obtained from cadavers with no history of chronic rhinosinusitis. Solid particles were found in 90% of tissue samples in the group with chronic rhinosinusitis, showing histologic signs of inflammation in 95%, while in the control group, the particles were found in 20% of samples, with normal histologic findings in all of them. The main detected compounds were graphite, TiO2, amorphous carbon, calcite, ankerite and iron compounds. The results are in accordance with the premise that exogenous airborne particles interact with the nasal mucosa and possibly deposit in it in cases where the epithelial barrier is compromised in chronic rhinosinusitis.

Traffic pollution tracers in the lymphatic system tissue of children-possible link to chronic tonsillitis development: pilot study.

The origin of metal elements in tonsillar tissues of children patients was investigated in order to establish the link between environmental pollution and tonsilitis diagnosis. The children lived either in a polluted, industrial region (Moravian-Silesian Region, North-East Czechia) or a clean, predominantly agricultural region (South Bohemian Region, South-East Czechia). Simultaneously, the distance of the address of the patients to the closest main road was assessed. The elemental content of the present particulate matter in the tonsil samples, coming from indicated tonsillectomies, was analysed using scanning electron microscopy equipped with an X-ray microprobe. No significant association of the elemental composition and the region was found using both bivariate and multivariate methods; however, an association with the distance to the closest main road was found. The study presents a novel assessment of the tonsillar tissues and supports the link between environmental factors (traffic-related particulate pollution) and the onset of chronic, idiopathic diseases in children, which has been debated recently.

Identification of the phase composition of solid microparticles in the nasal mucosa of patients with chronic hypertrophic rhinitis using Raman microspectroscopy.

Solid particles, predominantly in micron and submicron sizes, have repeatedly been observed as a threat to a human health unique compared to the other textures of the same materials. In this work, the hypothesis the solid metal-based particles play a role in the pathogenesis of chronic hypertrophic rhinitis was investigated in patients who had not responded positively to medication. In the group of 40 randomly selected patients indicated for surgical mucotomy, the presence of solid micro- and submicron particles present in their nasal mucosa was assessed. For comparison, a set of 13 reference samples from patients without diagnosed chronic hypertrophic rhinitis was evaluated. The analysis was performed using Raman microspectroscopy. The advantage of this method is the direct identification of compounds. The main detected compounds in the mucosa samples of patients with chronic hypertrophic rhinitis were TiO2, carbon-based compounds, CaCO3, Ca(Fe, Mg, Mn)(CO3)2 MgCO3, Fe2O3, BaSO4, FeCO3 and compounds of Al and Si, all of which may pose a health risk to a living organism. In the reference samples, only TiO2 and amorphous carbon were found. In the control group mucosa, a significantly lower presence of most of the assessed compounds was found despite the longer time they had to accumulate them due to their higher mean age. Identification and characterisation of such chemicals compounds in a living organism could contribute to the overall picture of the health of the individual and lead to a better understanding of the possible causes not only in the chronic hypertrophic rhinitis, but also in other mucosal and idiopathic diseases.

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.

The presence of fine and ultrafine particulate matter in the work environment.

This study presents the results of pilot measurement, where the exposure of fine and ultrafine particulate matter was monitored. The measurement was performed in welding workplace, where these particles are produced unintentionally. The measurement consisted of collecting information and measuring the concentration of particles in the workplace, where data collection was focused only on inhalation exposure. During welding, primarily 300 nm size particles are produced, and their concentration is strongly influenced by the welding material, type of welding and suction. The particles are amorphous in terms of morphology and contain manganese, iron and silicon, which can cause neurodegenerative diseases. Furthermore, the results indicate the importance of monitoring oral exposure.

Metal particles in mucus and hypertrophic tissue of the inferior nasal turbinates from the human upper respiratory tract.

Mucosal surfaces are the first mechanical barrier preventing the entry of foreign particles into the organism. The study addresses the detection and analysis of metal-based solid particles in cytological mucus samples from the surface of human hypertrophic tissue in the inferior nasal turbinates in patients diagnosed with chronic rhinitis. Solid particles were characterized by scanning electron microscopy and Raman microspectroscopy; all the biological samples were also subjected to vibration magnetometry. Since the upper airways are the first part of the respiratory tract, which is exposed to inhaled particles, it can be assumed that inhaled particles may be partially deposited in this region. Scanning electron microscopy revealed the presence of metal-based solid particles/clusters in the majority of the analysed cytological mucus samples and also in hypertrophic tissues; in all groups, the particles were of submicron size. Raman microspectroscopy detected the presence of particles/clusters based on amorphous carbon, graphite, calcium carbonate, anatase and barite only in the hypertrophic tissue. The obtained results show that the composition of some of the solid particles (i.e. Ba, Zn, Fe and Ti) detected in the mucus from the surface of the hypertrophic tissues resembled the particles found in the hypertrophic tissue itself. It can be assumed that after the capture of the inhaled particles by the mucus, they penetrate into the deeper layers of tissue.

Detection of Micron and Submicron Particles in Human Bronchogenic Carcinomas.

Metal based particles were detected in pulmonary tumor tissue samples and reference lung tissue samples (lung tissue without carcinoma) by Raman microspectroscopy and scanning electron microscopy. Many of these particles were in the size below 1 µm. Using scanning electron microscopy, particles based on iron were found in the majority of samples. Siderite was determined as the form of the iron in several samples by Raman microspectroscopy. The hypothesis that significant statistical dependence exists between the presence of metals in the lung tissue and lung cancer incidence was not proved. However, statistical dependence between smoking and lung cancer incidence was determined as well as insignificant correlation between the presence of titanium based particles and lung cancer incidence. Titanium-based compounds were identified as TiO2 in the form of anatase and rutile. Both the reference and the carcinoma samples exhibited magnetic properties as confirmed by vibration magnetometry measurements.

Determination of Oxidative Potential Caused by Brake Wear Debris in Non-Cellular Systems.

Wear debris from automotive brake systems represents a major source of non-exhaust emissions from road traffic and its production increases with number of cars worldwide. However, impact of brake wear debris on the environment and organisms is still not clear. One of the most possible ways by which these particles may affect living organisms is oxidative stress. Production of reactive oxidative species may cause damage of basic cell components, lipids, proteins, etc. Aim of this study is to perform characterization of airborne and nonairborne fractions of brake wear debris generated during standard dynamometer tests and evaluation of its potential to induce oxidative stress via lipid peroxidation and carbonylation of proteins in non-cellular system. Elemental and phase composition were determined by scanning electron microscopy, Raman microspectroscopy, and X-ray powder diffraction analysis. Carbon in amorphous form and graphite, copper, and iron in form of oxides were identified as major components in both studied fractions. Characteristic size of studied wear particles was evaluated by dynamic light scattering. Both airborne and nonairborne samples showed ability to induce oxidative stress which results from determination of carbonylated proteins.

Settled Dust from Urban and Suburban Roads in an Industrial City Area: Location and Seasonal Differences in Metal Content.

Settled road dust, present on all roads surfaces in a relatively high abundance, is a complex of particles-ranging from nanosized to microsized-from both natural and anthropogenic sources and may pose possible risk to the biosphere as well as influence the atmosphere because of the road dust resuspension. Geographical and seasonal differences in heavy metal content of the settled road dust were studied at two sites: urban site with a heavy traffic in the industrial city of Ostrava, Czech Republic and suburban site of Ostrava with a negligible traffic load in settlement Ludgerovice. Dust samples were collected monthly during the period from March to October 2015. Obtained dust samples were homogenized and subsequently analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy; the results were then assessed by multivariate statistical methods (Principal components analysis, Factorial analysis on mixed data). The difference in the content of Ba, Cr, Cu, Mn, Ni, Pb, Sb, Sn, V, and Zn was explainable mainly by the factor of the site only the content of Fe was significantly dependent on the month of sampling. The contents of the particular elements and the correlations found among them confirm the assumption that heavy metals detected in the road dust samples from the urban site most likely originated primarily from the traffic-and particularly from the non-combustion processes.

Settled iron-based road dust and its characteristics and possible association with detection in human tissues.

Settled road dust was examined to detect the presence of non-airborne submicron and nano-sized iron-based particles and to characterize these particles. Samples were collected from a road surface near a busy road junction in the city of Ostrava, Czech Republic, once a month from March to October. The eight collected samples were subjected to a combination of experimental techniques including elemental analysis, Raman microspectroscopy, scanning electron microscopy (SEM) analysis, and magnetometry. The data thereby obtained confirmed the presence of non-agglomerated spherical nano-sized iron-based particles, with average sizes ranging from 2 down to 490 nm. There are several sources in road traffic which generate road dust particles, including exhaust and non-exhaust processes. Some of them (e.g., brake wear) produce iron as the dominant metallic element. Raman microspectroscopy revealed forms of iron (mainly as oxides, Fe2O3, and mixtures of Fe2O3 and Fe3O4). Moreover, Fe3O4 was also detected in samples of human tissues from the upper and lower respiratory tract. In view of the fact that no agglomeration of those particles was found by SEM, it is supposed that these particles may be easily resuspended and represent a risk to human health due to inhalation exposure, as proved by the detection of particles with similar morphology and phase composition in human tissues.

Toxicity and mutagenicity of low-metallic automotive brake pad materials.

Organic friction materials are standardly used in brakes of small planes, railroad vehicles, trucks and passenger cars. The growing transportation sector requires a better understanding of the negative impact related to the release of potentially hazardous materials into the environment. This includes brakes which can release enormous quantities of wear particulates. This paper addresses in vitro detection of toxic and mutagenic potency of one model and two commercially available low-metallic automotive brake pads used in passenger cars sold in the EU market. The model pad made in the laboratory was also subjected to a standardized brake dynamometer test and the generated non-airborne wear particles were also investigated. Qualitative "organic composition" was determined by GC/MS screening of dichloromethane extracts. Acute toxicity and mutagenicity of four investigated sample types were assessed in vitro by bioluminescence assay using marine bacteria Vibrio fischeri and by two bacterial bioassays i) Ames test on Salmonella typhimurium His(-) and ii) SOS Chromotest using Escherichia coli PQ37 strain. Screening of organic composition revealed a high variety of organic compounds present in the initial brake pads and also in the generated non-airborne wear debris. Several detected compounds are classified by IARC as possibly carcinogenic to humans, e. g. benzene derivatives. Acute toxicity bioassay revealed a response of bacterial cells after exposure to all samples used. Phenolic resin and wear debris were found to be acutely toxic; however in term of mutagenicity the response was negative. All non-friction exposed brake pad samples (a model pad and two commercial pad samples) were mutagenic with metabolic activation in vitro.

ZnO/graphite composites and its antibacterial activity at different conditions.

The paper reports laboratory preparation, characterization and in vitro evaluation of antibacterial activity of ZnO/graphite nanocomposites. Zinc chloride and sodium carbonate served as precursors for synthesis of zinc oxide, while micromilled and natural graphite were used as the matrix for ZnO nanoparticles anchoring. During the reaction of ZnCl2 with saturated aqueous solution of Na2CO3a new compound is created. During the calcination at the temperature of 500 °C this new precursors decomposes and ZnO nanoparticles are formed. Composites ZnO/graphite with 50 wt.% of ZnO particles were prepared. X-ray powder diffraction and Raman microspectroscopy served as phase-analytical methods. Scanning electron microscopy technique was used for morphology characterization of the prepared samples and EDS mapping for visualization of elemental distribution. A developed modification of the standard microdilution test was used for in vitro evaluation of daylight induced antibacterial activity and antibacterial activity at dark conditions. Common human pathogens served as microorganism for antibacterial assay. Antibacterial activity of ZnO/graphite composites could be based on photocatalytic reaction; however there is a role of Zn(2+) ions on the resulting antibacterial activity which proved the experiments in dark condition. There is synergistic effect between Zn(2+) caused and reactive oxygen species caused antibacterial activity.

Micro- and Nanosized Particles in Nasal Mucosa: A Pilot Study.

OBJECTIVE: The aim of this prospective study is to evaluate presence and quantity of micro- and nanosized particles (NPs) and interindividual differences in their distribution and composition in nasal mucosa. METHODS: Six samples of nasal mucosa obtained by mucotomy from patients with chronic hypertrophic rhinosinusitis were examined. Samples divided into 4 parts according to the distance from the nostrils were analyzed by scanning electron microscopy and Raman microspectroscopy to detect solid particles and characterize their morphology and composition. A novel method of quantification of the particles was designed and used to evaluate interindividual differences in distribution of the particles. The findings were compared with patients' employment history. RESULTS: In all the samples, NPs of different elemental composition were found (iron, barium, copper, titanium, etc.), predominantly in the parts most distant from nostrils, in various depths from the surface of the mucosa and interindividual differences in their quantity and composition were found, possibly in relation to professional exposition. CONCLUSIONS: This study has proven the possibility of quantification of distribution of micro- and nanosized particles in tissue samples and that the NPs may deposit in deeper layers of mucosa and their elemental composition may be related to professional exposition to the sources of NPs.