Impact of indoor air pollution on DNA damage and chromosome stability: a systematic review.

Indoor air pollution is becoming a rising public health problem and is largely resulting from the burning of solid fuels and heating in households. Burning these fuels produces harmful compounds, such as particulate matter regarded as a major health risk, particularly affecting the onset and exacerbation of respiratory diseases. As exposure to polluted indoor air can cause DNA damage including DNA sd breaks as well as chromosomal damage, in this paper, we aim to provide an overview of the impact of indoor air pollution on DNA damage and genome stability by reviewing the scientific papers that have used the comet, micronucleus, and γ-H2AX assays. These methods are valuable tools in human biomonitoring and for studying the mechanisms of action of various pollutants, and are readily used for the assessment of primary DNA damage and genome instability induced by air pollutants by measuring different aspects of DNA and chromosomal damage. Based on our search, in selected studies (in vitro, animal models, and human biomonitoring), we found generally higher levels of DNA strand breaks and chromosomal damage due to indoor air pollutants compared to matched control or unexposed groups. In summary, our systematic review reveals the importance of the comet, micronucleus, and γ-H2AX assays as sensitive tools for the evaluation of DNA and genome damaging potential of different indoor air pollutants. Additionally, research in this particular direction is warranted since little is still known about the level of indoor air pollution in households or public buildings and its impact on genetic material. Future studies should focus on research investigating the possible impact of indoor air pollutants in complex mixtures on the genome and relate pollutants to possible health outcomes.

Probiotic bacteria isolated from fermented meat displays high antioxidant and anti-inflammatory potential.

One of the ways to impact emerging problems of unhealthy diet such as microbiota dysbiosis, inflammation, and oxidative stress is the application of probiotics and their incorporation into different food matrices. Discovery and selection of appropriate probiotic bacteria is challenging procedure especially for fermented meat products that have also been described as a potential source of resilient probiotic microorganisms. The aim of this study was to investigate probiotic bacteria Lactiplantibacillus plantarum 1K isolated from traditional fermented meat product for its potential beneficial properties. Furthermore, small probiotic metabolites were extracted, and their anti-inflammatory activity was tested in a lipopolysaccharide-stimulated inflammatory model on human peripheral blood mononuclear cells (PBMCs). Safety characteristics of metabolites including cytotoxicity and genotoxicity were also determined. Investigated probiotic strain exerted high antioxidant potential by viable cells but also by metabolite fraction. Viable cells retained the satisfactory antioxidant activity after gastrointestinal transit. Extracted probiotic metabolites significantly inhibited TNF-α production in LPS-stimulated PBMC thus exerting anti-inflammatory activity. Metabolites alone showed no cytotoxic or genotoxic activity toward isolated immune cells. Obtained results indicate the possibility to use fermented meat products as sources for specific probiotics that might provide antioxidant and anti-inflammatory benefits for the consumers.

Inflammatory, oxidative and DNA damage status in vegetarians: is the future of human diet green?

The health benefit of a vegetarian diet is still under debate as it may result in a higher intake of some beneficial micronutrients, while others may be reduced, thus influencing various metabolic pathways and health-related biomarkers. This scoping review discusses inflammatory, oxidative and DNA damage status in vegetarians and vegans compared to omnivores. Most of the reviewed studies indicated favorable effects of a vegetarian diet on oxidative status compared to omnivores but did not clearly associate particular dietary habits to genome damage. The evidence on the effect of vegetarian diet on the inflammatory and immunological biomarkers is poor, which could at least partly be explained by methodological constraints such as small sample size, short duration of vegetarianism and inconsistent definitions of the omnivorous diet. The only inflammatory biomarker that seems to be associated with the vegetarian diet was inflammatory mediator C-reactive protein, which in several studies showed lower values in vegetarians as compared to omnivores. There were very few studies on immunological markers and the results on the difference between vegetarians and omnivores were inconclusive. Although several biomarkers involved in oxidative stress and inflammation showed a beneficial association with the vegetarian diet, further research in well-defined and sufficiently sized cohorts is needed to provide more evidence.

Impact of Deoxynivalenol and Zearalenone as Single and Combined Treatment on DNA, Cell Cycle and Cell Proliferation in HepG2 Cells.

The study aimed to investigate toxicity and the mechanism of toxicity of two Fusarium mycotoxins, deoxynivalenol (DON) and zearalenone (ZEA). DON and ZEA were applied to HepG2 cells as single compounds and in combination at low environmentally relevant concentrations. HepG2 cells were exposed to DON (0.5, 1, and 2 µM), ZEA (5, 10, and 20 µM) or their combinations (1 µM DON + 5 µM ZEA, 1 µM DON + 10 µM ZEA and 1 µM DON + 20 µM ZEA) for 24 h and cell viability, DNA damage, cell cycle and proliferation were assessed. Both mycotoxins reduced cell viability, however, combined treatment with DON and ZEA resulted in higher reduction of cell viability. DON (1 µM) induced primary DNA damage, while DON (1 µM) in combination with higher ZEA concentrations showed antagonistic effects compared to DON alone at 1 µM. DON arrested HepG2 cells in G2 phase and significantly inhibited cell proliferation, while ZEA had no significant effect on cell cycle. The combined treatment with DON and ZEA arrested cells in G2 phase to a higher extend compared to treatment with single mycotoxins. Potentiating effect observed after DON and ZEA co-exposure at environmentally relevant concentrations indicates that in risk assessment and setting governments' regulations, mixtures of mycotoxins should be considered.

Phytotoxicity of Bisphenol A to Allium cepa Root Cells Is Mediated through Growth Hormone Gibberellic Acid and Reactive Oxygen Species.

The aim of this study was to test the phytotoxicity and mode of action of bisphenol A (BPA) on Allium cepa using a multibiomarker approach. A. cepa roots were exposed to BPA in concentration range 0-50 mg L-1 for 3 days. BPA even in the lowest applied concentration (1 mg L-1) reduced root length, root fresh weight, and mitotic index. Additionally, the lowest BPA concentration (1 mg L-1) decreased the level of gibberellic acid (GA3) in root cells. BPA at concentration 5 mg L-1 increased production of reactive oxygen species (ROS) that was followed by increase in oxidative damage to cells' lipids and proteins and activity of enzyme superoxide dismutase. BPA in higher concentrations (25 and 50 mg L-1) induced genome damage detected as an increase in micronucleus (MNs) and nuclear buds (NBUDs). BPA at >25 mg L-1 induced synthesis of phytochemicals. Results of this study using multibiomarker approach indicate that BPA is phytotoxic to A. cepa roots and has shown genotoxic potential to plants, thus its presence in the environment should be monitored.

Probiotic and paraprobiotic derivates exhibit anti-inflammatory and genoprotective effects during induced stress.

AIMS: The literature highlights the pathology of inflammation and its role in carcinogenesis, ageing and related diseases. Inflammatory processes induce oxidative stress and reduce antioxidant capacity. This study investigated the antioxidant and anti-inflammatory potential of probiotic bacteria isolated from fermented whey under conditions of induced stress. METHODS AND RESULTS: Functional antioxidant characterization of potential probiotic bacteria Lactiplantibacillus plantarum S1 was performed under different growth conditions (aerobic, respiratory and anaerobic) and under stress to find the conditions that yield the most effective cells. Since aerobic growth yielded the most potent cells, the free radical scavenging ability of live and heat-killed cells was measured before and after exposure to gastrointestinal conditions. For heat-killed cells and extracted probiotic metabolites, the reduction of DNA damage to immune cells was determined in the hydrogen peroxide exposure comet assay. The combination of inactivated cells and metabolites showed the best reduction in DNA damage. Finally, in the LPS inflammation model, the aforementioned probiotic metabolites significantly reduced Tumour necrosis factor-alpha levels in immune cells. CONCLUSIONS: Whey-derived potential probiotic bacteria exert antioxidant and anti-inflammatory effects, and based on this study, we propose a model combining inactivated cells and metabolites to reduce inflammatory and oxidative stress-related adverse effects. SIGNIFICANCE AND IMPACT OF STUDY: In this study, a new probiotic model is proposed for continuous use to reduce oxidative and inflammatory stress in the gut.

Characterisation and toxicological activity of three different Pseudo-nitzschia species from the northern Adriatic Sea (Croatia).

Diatoms of the genus Pseudo-nitzschia are cosmopolitans spread in seas and oceans worldwide, with more than 50 described species, dozens of which have been confirmed to produce domoic acid (DA). Here, we characterized and investigated the toxicological activity of secondary metabolites excreted into the growth media of different Pseudo-nitzschia species sampled at various locations in the northern Adriatic Sea (Croatia) using human blood cells under in vitro conditions. The results revealed that three investigated species of the genus Pseudo-nitzschia were capable of producing DA indicating their toxic potential. Moreover, toxicological data suggested all three Pseudo-nitzschia species can excrete toxic secondary metabolites into the surrounding media in addition to the intracellular pools of DA, raising concerns regarding their toxicity and environmental impact. In addition, all three Pseudo-nitzchia species triggered oxidative stress, one of the mechanisms of action likely responsible for the DNA damage observed in human blood cells. In line with the above stated, our results are of great interest to environmental toxicologists, the public and policy makers, especially in light of today's climate change, which favours harmful algal blooms and the growth of DA producers with a presumed negative impact on the public health of coastal residents.

Associating Air Pollution with Cytokinesis-Block Micronucleus Assay Parameters in Lymphocytes of the General Population in Zagreb (Croatia).

Air pollution is recognized as one of the most serious public health issues worldwide and was declared to be a leading environmental cause of cancer deaths. At the same time, the cytokinesis-block micronucleus (CBMN) assay serves as a cancer predictive method that is extensively used in human biomonitoring for populations exposed to environmental contamination. The objective of this cross-sectional study is two-fold: to evaluate genomic instability in a sample (N = 130) of healthy, general population residents from Zagreb (Croatia), chronically exposed to different levels of air pollution, and to relate them to air pollution levels in the period from 2011 to 2015. Measured frequencies of CBMN assay parameters were in agreement with the baseline data for the general population of Croatia. Air pollution exposure was based on four factors obtained from a factor analysis of all exposure data obtained for the examined period. Based on the statistical results, we did not observe a significant positive association between any of the CBMN assay parameters tested and measured air pollution parameters for designated time windows, except for benzo(a)pyrene (B[a]P) that showed significant negative association. Our results show that measured air pollution parameters are largely below the regulatory limits, except for B[a]P, and as such, they do not affect CBMN assay parameters' frequency. Nevertheless, as air pollution is identified as a major health threat, it is necessary to conduct prospective studies investigating the effect of air pollution on genome integrity and human health.

Selected polyoxopalladates as promising and selective antitumor drug candidates.

Polyoxo-noble-metalates (PONMs), a class of molecular noble metal-oxo nanoclusters that combine features of both polyoxometalates and noble metals, are a promising platform for the development of next-generation antitumor metallodrugs. This study aimed to evaluate the antitumor potential against human neuroblastoma cells (SH-SY5Y), as well as toxicity towards healthy human peripheral blood cells (HPBCs), of five polyoxopalladates(II): (Na8[Pd13As8O34(OH)6]·42H2O (Pd13), Na4[SrPd12O6(OH)3(PhAsO3)6(OAc)3]·2NaOAc·32H2O (SrPd12), Na6[Pd13(AsPh)8O32]·23H2O (Pd13L), Na12[SnO8Pd12(PO4)8]·43H2O (SnPd12), and Na12[PbO8Pd12(PO4)8]·38H2O (PbPd12)), as the largest subset of PONMs. A pure inorganic, Pd13, was found as the most potent and selective antineuroblastoma agent with IC50 values (µM) of 7.2 ± 2.2 and 4.4 ± 1.2 for 24 and 48 h treatment, respectively, even lower than cisplatin (28.4 ± 7.4 and 11.6 ± 0.8). The obtained IC50 values (µM) for 24/48 h treatment with SrPd12 and Pd13L were 75.8 ± 6.7/76.7 ± 22.9 and 63.8 ± 3.6/21.4 ± 10.8, respectively, whereas SnPd12 and PbPd12 did not remarkably affect the SH-SY5Y viability (IC50 > > 100 µM). Pd13 caused depolarisation of inner mitochondrial membrane prior to superoxide ion hyperproduction, followed by caspase activation, DNA fragmentation and cell cycle arrest, all hallmarks of apoptotic cell death, and accompanied by an increase in acidic vesicles content, suggestive of autophagy induction. Importantly, Pd13 demonstrated the antitumor effect at concentrations not cytogenotoxic for normal HPBCs. On the contrary, SrPd12 and Pd13L at concentrations ≥ 1/3 IC50 (24 h) decreased HPBC viability and increased % tail DNA up to 42% and 3.05 times, respectively, related to control. SnPd12 and PbPd12, previously confirmed promising antileukemic agents, did not exhibit cytogenotoxicity to HPBCs, and thus could be regarded as tumor cell specific and selective drug candidates.

Natural Products Counteracting Cardiotoxicity during Cancer Chemotherapy: The Special Case of Doxorubicin, a Comprehensive Review.

Cardiotoxicity is a frequent undesirable phenomenon observed during oncological treatment that limits the therapeutic dose of antitumor drugs and thus may decrease the effectiveness of cancer eradication. Almost all antitumor drugs exhibit toxic properties towards cardiac muscle. One of the underlying causes of cardiotoxicity is the stimulation of oxidative stress by chemotherapy. This suggests that an appropriately designed diet or dietary supplements based on edible plants rich in antioxidants could decrease the toxicity of antitumor drugs and diminish the risk of cardiac failure. This comprehensive review compares the cardioprotective efficacy of edible plant extracts and foodborne phytochemicals whose beneficial activity was demonstrated in various models in vivo and in vitro. The studies selected for this review concentrated on a therapy frequently applied in cancer, anthracycline antibiotic-doxorubicin-as the oxidative stress- and cardiotoxicity-inducing agent.

The genotoxicity of an organic solvent mixture: A human biomonitoring study and translation of a real-scenario exposure to in vitro.

This study aimed to evaluate occupational exposure to a styrene and xylene mixture through environmental exposure assessment and identify the potential genotoxic effects through biological monitoring. Secondly, we also exposed human peripheral blood cells in vitro to both xylene and styrene either alone or in mixture at concentrations found in occupational settings in order to understand their mechanism of action. The results obtained by air monitoring were below the occupational exposure limits for both substances. All biomarkers of effect, except for nucleoplasmic bridges, had higher mean values in workers (N = 17) compared to the corresponding controls (N = 17). There were statistically significant associations between exposed individuals and the presence of nuclear buds and oxidative damage. As for in vitro results, there was no significant influence on primary DNA damage in blood cells as evaluated by the comet assay. On the contrary, we did observe a significant increase of micronuclei and nuclear buds, but not nucleoplasmic bridges upon in vitro exposure. Taken together, both styrene and xylene have the potential to induce genomic instability either alone or in combination, showing higher effects when combined. The obtained data suggested that thresholds for individual chemicals might be insufficient for ensuring the protection of human health.

Optimization of a fast screening method for the assessment of low molecular weight thiols in human blood and plasma suitable for biomonitoring studies.

An adequate level of low molecular weight thiols (LMW-SH, especially glutathione (GSH)) protects cellular macromolecules against toxic agents, and is used as a sensitive biomarker of exposure to toxic compounds. During sample collection, storage and preparation, non-enzymatic and enzymatic oxidation of LMW-SH can occur leading to analytical inaccuracy. The aim of this study was to optimize a fast and reliable screening method for the determination of LMW-SH, mainly GSH, in blood and plasma samples as well as to investigate the impact of storage conditions on the LMW-SH stability. Based on our results, the described spectrophotometric method allows fast and reliable determination of LMW-SH in blood and plasma samples. Results on incubation of samples at 37 °C imply that synthesis of LMW-SH (probably GSH) as well as dynamic interexchange among various thiols forms can be induced in blood cells in in vitro conditions. Importantly, the level of LMW-SH in blood and plasma stored at -20 °C was constant, indicating that they can be stored at -20 °C for at least 30 days. Therefore, the method is suitable for assessment of LMW-SH in long-term human biomonitoring as well as environmental field studies, especially those involving a large number of samples such as epidemiological studies.

Critical evaluation of the use of total reflection X-ray fluorescence spectrometry for the analysis of whole blood samples: application to patients with thyroid gland diseases.

Multielemental analysis of whole blood can provide significant information for the evaluation of nutritional status and diagnosis of certain diseases as well as for the assessment of exposure to potentially toxic metals. However, the quantification of multiple elements in whole blood is not easy partly because of the wide variation in element concentrations (from ng L-1 to g L-1) and the complex matrix. The aim of this work was to develop a fast, sustainable, and reliable analytical method, in combination with low-power TXRF, for multielemental analysis of blood samples. Firstly, a set of experiments were carried out to select the best diluent type and dilution factor using the control material SeronormTM Trace Elements Whole Blood L-1. A critical evaluation of the parameters affecting the sample deposition on the reflector was also carried out including a study of the shape and element distribution of the deposited residue on the reflector by micro X-ray fluorescence spectrometry. Using the best analytical conditions, limits of detection estimated were in the low milligrams per kilogram range and similar to those obtained using more complex sample treatments such as digestion. Accuracy and precision of the results were in most cases acceptable (recoveries 89-102%, RSD 6-8%, n = 5). Only underestimated values were obtained for light elements such as potassium. To prove the applicability of the method, several blood samples from control and thyroid disease patients were analyzed. Despite the fact that more samples need to be analyzed, it seems that Zn and Br contents in some of the patients are significantly higher compared to control samples. Graphical abstract.

Evaluation of oxidative stress responses in human circulating blood cells after imatinib mesylate treatment - Implications to its mechanism of action.

Imatinib mesylate (IM) is the first developed protein kinase inhibitor and recently it has topped consumption rates among targeted and total anticancer drugs. Although there are indications that IM possesses cyto/genotoxic activities against normal non-target cells as well, there is a lack of information regarding the underlying mechanism involved in those actions. Therefore, we aimed to evaluate the response of human circulating blood cells towards oxidative stress after IM treatment (0.0001-10 µg/mL) in vitro. Based on the results, IM had an influence on all of the oxidative stress parameters tested. Lower concentrations of IM induced an increase of glutathione level, following its decrease at higher IM concentrations indicating impairment in oxidative stress defences. Concomitant to a glutathione decrease, an increase of malondialdehyde and protein carbonyls level was observed indicating oxidative damage of lipids and proteins. The observed effects overlapped with the observed formation of oxidative base damage detected by formamidopyrimidine-DNA glycosylase modified-comet assay indicating that IM managed to induce oxidative DNA damage. Our results provide novelty in their mechanistic approach to IM-induced toxicity in non-target cells and suggest that IM can affect blood cells and induce oxidative stress.

Seasonal variations as predictive factors of the comet assay parameters: a retrospective study.

Since there are several predicting factors associated with the comet assay parameters, we have decided to assess the impact of seasonal variations on the comet assay results. A total of 162 volunteers were retrospectively studied, based on the date when blood donations were made. The groups (winter, spring, summer and autumn) were matched in terms of age, gender, smoking status, body mass index and medical diagnostic exposure in order to minimise the impact of other possible predictors. Means and medians of the comet assay parameters were higher when blood was sampled in the warmer period of the year, the values of parameters being the highest during summer. Correlation of meteorological data (air temperature, sun radiation and sun insolation) was observed when data were presented as the median per person. Using multivariate analysis, sampling season and exposure to medical radiation were proved to be the most influential predictors for the comet assay parameters. Taken together, seasonal variation is another variable that needs to be accounted for when conducting a cohort study. Further studies are needed in order to improve the statistical power of the results related to the impact of sun radiation, air temperature and sun insolation on the comet assay parameters.

Genotoxicity assessment of a selected cytostatic drug mixture in human lymphocytes: A study based on concentrations relevant for occupational exposure.

Cytostatic drugs are highly cytotoxic agents used in cancer treatment and although their benefit is unquestionable, they have been recognized as hazardous to healthcare professionals in occupational settings. In a working environment, simultaneous exposure to cytostatics may occur creating a higher risk than that of a single substance. Hence, the present study evaluated the combined cyto/genotoxicity of a mixture of selected cytostatics with different mechanisms of action (MoA; 5-fluorouracil, cyclophosphamide and paclitaxel) towards human lymphocytes in vitro at a concentration range relevant for occupational as well as environmental exposure. The results suggest that the selected cytostatic drug mixture is potentially cyto/genotoxic and that it can induce cell and genome damage even at low concentrations. This indicates not only that such mixture may pose a risk to cell and genome integrity, but also that single compound toxicity data are not sufficient for the prediction of toxicity in a complex working environment. The presence of drugs in different amounts and with different MoA suggests the need to study the relationship between the presence of genotoxic components in the mixture and the resulting effects, taking into account the MoA of each component by itself. Therefore, this study provides new data sets necessary for scientifically-based risk assessments of cytostatic drug mixtures in occupational as well as environmental settings.

Cytokinesis-block micronucleus cytome assay parameters in peripheral blood lymphocytes of the general population: Contribution of age, sex, seasonal variations and lifestyle factors.

The cytokinesis-block micronucleus cytome (CBMN Cyt) assay was used to evaluate the baseline frequency of cytogenetic damage in peripheral blood lymphocytes of the general population (average age, 38.28 ± 12.83 years) in relation to age, sex, body mass index, seasonal variations (season of sampling, period of sampling and different meteorological parameters) and lifestyle factors (smoking habit, alcohol consumption, exposure to medications and diagnostic radiation, physical activity, and family history of cancer). The background frequency of micronuclei (MNi) for the 200 subjects assayed was 5.06 ± 3.11 per 1000 binucleated cells, while the mean frequency of nucleoplasmic bridges (NPBs) was 1.21 ± 1.46 and of nuclear buds (NBUDs) 3.48 ± 2.14. The background frequency of apoptosis and necrosis was 1.58 ± 1.50 and 1.39 ± 1.56, respectively, while the mean nuclear division index (NDI) was 1.99 ± 0.14. The cut-off value, which corresponds to the 95th percentile of the distribution of 200 individual values, was 11 MNi, 4 NPBs and 7 NBUDs. The study also confirmed an association of the above mentioned parameters with age, sex and several lifestyle factors. Moreover, significant confounders based on our results are also sampling season, sampling period and different meteorological parameters that were dependent on the CBMN Cyt assay parameters. In line with the above mentioned, several factors should be taken into account when it comes to the monitoring of exposed populations using cytogenetic biomarkers. Moreover, the normal and cut-off values obtained in this study present background data for the general population, and can later serve as baseline values for further biomonitoring studies.

In vitro effects of simultaneous exposure to platinum and cadmium on the activity of antioxidant enzymes and DNA damage and potential protective effects of selenium and zinc.

Circulating platinum (Pt) is detectable in the blood of Pt-treated cancer patients for over a decade after the treatment. Prolonged exposure to Pt, in combination with adverse compounds from nutrition and lifestyle, such as cadmium (Cd), could increase the risk from second cancers. The aim of this study was to investigate the effects of simultaneous exposure to Cd- and Pt-compounds on oxidative and DNA damage and the possible protective effects of zinc (Zn) and selenium (Se). The aqueous solutions of PtCl4, CdCl2 × H2O, ZnCl2 and Na2SeO3 were added, alone or in combination, to whole blood and isolated erythrocytes to produce the final concentrations of 2000 µg/L of Pt, 8 µg/L of Cd, 100 µg/L of Se, and 1000 µg/L of Zn. The activity of copper, zinc-superoxide dismutase, glutathione peroxidase and glutathione in whole blood was determined after 1 h exposure in in vitro conditions. The induction of DNA strand-breaks in human peripheral blood leukocytes was determined with the alkaline comet assay after 24 h exposure. Exposure to Pt and/or Cd decreased the activities of antioxidant enzymes and elevated DNA damage compared to control. A statistically significant change in the activity of both enzymes and in the induction of DNA strand-breaks was observed in the cells treated with Pt + Cd combination, while the addition of Se and/or Zn resulted in partial recovery of these effects. The results indicate that combined exposure to Pt and Cd could disrupt antioxidant protection of the organism and increase DNA damage, whereas Se and Zn could partially ameliorate these harmful effects.

Physico-chemical characterization and the in vitro genotoxicity of medical implants metal alloy (TiAlV and CoCrMo) and polyethylene particles in human lymphocytes.

BACKGROUND: The main objective of the present study was to investigate chemical composition and possible cyto/genotoxic potential of several medical implant materials commonly used in total hip joint replacement. METHODS: Medical implant metal alloy (Ti6Al4V and CoCrMo) and high density polyethylene particles were analyzed by energy dispersive X-ray spectrometry while toxicological characterization was done on human lymphocytes using multi-biomarker approach. RESULTS: Energy dispersive X-ray spectrometry showed that none of the elements identified deviate from the chemical composition defined by appropriate ISO standard. Toxicological characterization showed that the tested materials were non-cyto/genotoxic as determined by the comet and cytokinesis-block micronucleus (CBMN) assay. Particle morphology was found (by using scanning electron and optical microscope) as flat, sharp-edged, irregularly shaped fiber-like grains with the mean particle size less than 10µm; this corresponds to the so-called "submicron wear". The very large surface area per wear volume enables high reactivity with surrounding media and cellular elements. CONCLUSIONS: Although orthopedic implants proved to be non-cyto/genotoxic, in tested concentration (10µg/ml) there is a constant need for monitoring of patients that have implanted artificial hips or other joints, to minimize the risks of any unwanted health effects. GENERAL SIGNIFICANCE: The fractal and multifractal analyses, performed in order to evaluate the degree of particle shape effect, showed that the fractal and multifractal terms are related to the "remnant" level of the particles' toxicity especially with the cell viability (trypan blue method) and total number of nucleoplasmic bridges and nuclear buds as CBMN assay parameters.