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Microplastics (MPs) are ubiquitous anthropogenic contaminants, and their abundance in the entire ecosystem raises the question of how far is the impact of these MPs on the biota, humans, and the environment. Recent research has overemphasized the occurrence, characterization, and direct toxicity of MPs; however, determining and understanding their genotoxic effect is still limited. Thus, the present review addresses the genotoxic potential of these emerging contaminants in aquatic organisms and in human peripheral lymphocytes and identified the research gaps in this area. Several genotoxic endpoints were implicated, including the frequency of micronuclei (MN), nucleoplasmic bridge (NPB), nuclear buds (NBUD), DNA strand breaks, and the percentage of DNA in the tail (%Tail DNA). In addition, the mechanism of MPs-induced genotoxicity seems to be closely associated with reactive oxygen species (ROS) production, inflammatory responses, and DNA repair interference. However, the gathered information urges the need for more studies that present environmentally relevant conditions. Taken into consideration, the lifestyle changes within the COVID-19 pandemic, we discussed the impact of the pandemic on enhancing the genotoxic potential of MPs whether through increasing human exposure to MPs via inappropriate disposal and overconsumption of plastic-based products or by disrupting the defense system owing to unhealthy food and sleep deprivation as well as stress. Overall, this review provided a reference for the genotoxic effect of MPs, their mechanism of action, as well as the contribution of COVID-19 to increase the genotoxic risk of MPs. [Display omitted] • The genotoxic effects of MPs are determined in somatic cells of aquatic organisms and human peripheral lymphocytes. • The mechanism of MPs-induced genotoxicity is associated with oxidative stress, inflammation, and DNA repair disruption. • The COVID-19 pandemic contributes to the genotoxic potential of MPs. [ABSTRACT FROM AUTHOR]

The use of metal oxide nanoparticles (NPs) is steadily spreading, leading to increased environmental exposures to many organisms, including humans. To improve our knowledge of this potential hazard, we have evaluated the genotoxic risk of cerium oxide (CeO2NPs) and magnesium oxide (MgONPs) nanoparticle exposures using Drosophila as an in vivo assay model. In this study, two well-known assays, such as the wing somatic mutation and recombination test (wing-spot assay) and the single-cell gel electrophoresis test (comet assay) were used. As a novelty, and for the first time, changes in the expression levels of a wide panel of DNA repair genes were also evaluated. Our results indicate that none of the concentrations of CeO2NPs increased the total spot frequency in the wing-spot assay, while induction was observed at the highest dose of MgONPs. Regarding the comet assay, both tested NPs were unable to induce single DNA strand breaks or oxidative damage in DNA bases. Nevertheless, exposure to CeO2NPs induced significant increases in the expression levels of the Mlh1 and Brca2 genes, which are involved in the double-strand break repair pathway, together with a decrease in the expression levels of the MCPH1 and Rad51D genes. Regarding the effects of MgONPs exposure, the expression levels of the Ercc1, Brca2, Rad1, mu2, and stg genes were significantly increased, while Mlh1 and MCPH1 genes were decreased. Our results show the usefulness of our approach in detecting mild genotoxic effects by evaluating changes in the expression of a panel of genes involved in DNA repair pathways. [ABSTRACT FROM AUTHOR]

Iron oxide nanoparticles (IONPs) have useful properties, such as strong magnetism and compatibility with living organisms which is preferable for medical applications such as drug delivery and imaging. However, increasing use of these materials, especially in medicine, has raised concerns regarding potential risks to human health. In this study, IONPs were coated with silicon dioxide (SiO 2), citric acid (CA), and polyethylenimine (PEI) to enhance their dispersion and biocompatibility. Both coated and uncoated IONPs were assessed for genotoxic effects on Drosophila melanogaster. Results showed that uncoated IONPs induced genotoxic effects, including mutations and recombinations, while the coated IONPs demonstrated reduced or negligible genotoxicity. Additionally, bioinformatic analyses highlighted potential implications of induced recombination in various cancer types, underscoring the importance of understanding nanoparticle-induced genomic instability. This study highlights the importance of nanoparticle coatings in reducing potential genotoxic effects and emphasizes the necessity for comprehensive toxicity assessments in nanomaterial research. • Uncoated IONPs have both mutagenic and recombinogenic activity. • The IONPs were separately coated with three different coating materials. • SiO 2 , PEI and CA coatings reduced IONP genotoxicity. [ABSTRACT FROM AUTHOR]

Quaternary ammonium compounds (QACs) are commonly used as disinfectants for industrial, medical, and residential applications. However, adverse health outcomes have been reported. Therefore, biocompatible disinfectants must be developed to reduce these adverse effects. In this context, QACs with various alkyl chain lengths (C12–C18) were synthesized by reacting QACs with the counterion silane. The antimicrobial activities of the novel compounds against four strains of microorganisms were assessed. Several in vivo assays were conducted on Drosophila melanogaster to determine the toxicological outcomes of Si-QACs, followed by computational analyses (molecular docking, simulation, and prediction of skin sensitization). The in vivo results were combined using a cheminformatics approach to understand the descriptors responsible for the safety of Si-QAC. Si-QAC-2 was active against all tested bacteria, with minimal inhibitory concentrations ranging from 13.65 to 436.74 ppm. Drosophila exposed to Si-QAC-2 have moderate-to-low toxicological outcomes. The molecular weight, hydrophobicity/lipophilicity, and electron diffraction properties were identified as crucial descriptors for ensuring the safety of the Si-QACs. Furthermore, Si-QAC-2 exhibited good stability and notable antiviral potential with no signs of skin sensitization. Overall, Si-QAC-2 (C14) has the potential to be a novel disinfectant. [Display omitted] • New silane quaternary ammonium disinfectants were synthesized. • The antimicrobial effect depends on alkyl chain length and the presence of silane. • Mutagenicity/genotoxicity were observed on low alkyl chain compounds. • From in vivo / in silico data one compound (Si-QAC2) was selected as a promising disinfectant. • In silico data detect crucial descriptors to guarantee the safety of Si-QAC. [ABSTRACT FROM AUTHOR]

Many new pesticides are produced for use every year. Fungicides, one of the important subgroups of pesticides, are used to protect agricultural products from fungal infections. However, studies on the genotoxic potential of fungicides are still very limited. In this study, the genotoxic potentials of four commonly used fungicides (metiram, kresoxim-methyl, propamocarb and hymexazol) were investigated using the Drosophila Somatic Mutation and Recombination Test (SMART) and the Drosophila Single Cell Gel Electrophoresis Test (Drosophila Comet Test). Drosophila, which has been widely used in genetic studies in recent years, provides a powerful system in the use of genetic and molecular approaches in human genetic diseases research. As a model organism, Drosophila is in many ways similar to human systems. According to the results obtained from the study, it was determined that 4 fungicides whose genotoxic effects were investigated by SMART method did not induce genotoxicity. In the KOMET experiment, it was determined that the studied fungicides caused DNA single strand breakage. This study provides new data on the potential effects of pesticides on human health and possible genetic diseases. [ABSTRACT FROM AUTHOR]

The use of nanoparticles (NPs) has become widespread due to the increasing diversification of products from NP and the benefit of these products for economic, environmental and human health. However, this overutilize has also led to some concerns. NPs can show different toxic effects depending on their chemical composition, structure, particle size, surface area and shape. Their shape and size are important determinants in the cellular uptake and potential toxicity of NPs. Iron (III) oxide (Fe2O3) NPs are used in many biomedical and bioengineering fields such as magnetic resonance imaging, drug delivery, detoxification of biological fluids. In this study, COMET (alkaline single cell gel electrophoresis) analysis was performed with Drosophila hemocytes to determine the relationship between the genotoxicity of Fe2O3 NPs and particle size and shape. According to the result of COMET, no statistically significant difference was found in terms of genotoxicity when Fe2O3 NPs with of <50 nm and sphere form and Fe2O3 NPs with of <100 nm and rod form were compared. However, in both Fe2O3 NP treatments, it was determined that only 1 mM dose (between 1, 2 and 5 mM) was induced statistically significant level of genoxicity compared to the control group distilled water. [ABSTRACT FROM AUTHOR]

The use of nanoparticles (NPs) has become widespread due to the increasing diversification of products from NP and the benefit of these products for economic, environmental and human health. However, this overutilize has also led to some concerns. NPs can show different toxic effects depending on their chemical composition, structure, particle size, surface area and shape. Their shape and size are important determinants in the cellular uptake and potential toxicity of NPs. Iron (III) oxide (Fe2O3) NPs are used in many biomedical and bioengineering fields such as magnetic resonance imaging, drug delivery, detoxification of biological fluids. In this study, COMET (alkaline single cell gel electrophoresis) analysis was performed with Drosophila hemocytes to determine the relationship between the genotoxicity of Fe2O3 NPs and particle size and shape. According to the result of COMET, no statistically significant difference was found in terms of genotoxicity when Fe2O3 NPs with of <50 nm and sphere form and Fe2O3 NPs with of <100 nm and rod form were compared. However, in both Fe2O3 NP treatments, it was determined that only 1 mM dose (between 1, 2 and 5 mM) was induced statistically significant level of genoxicity compared to the control group distilled water. [ABSTRACT FROM AUTHOR]

Although the use of synthetic amorphous silica (SAS) is steady increasing, scarce information exists on its potential health risk. In particular few and conflictive data exist on its genotoxicity. To fill in this gap we have used Drosophila melanogaster as in vivo model test organism to detect the genotoxic activity of different SAS with different primary sizes (6, 15, 30 and 55 nm). The wing-spot assay and the comet assay in larvae haemocytes were used, and the obtained results were compared with those obtained with the microparticulated form (silicon dioxide). All compounds were administered to third instar larvae at concentrations ranging from 0.1 to 10 mM. No significant increases in the frequencies of mutant spots were observed in the wing-spot assay with any of the tested compounds. On the other hand, significant dose-dependent increases in the levels of primary DNA damage, measured by the comet assay, were observed for all the SAS evaluated but mainly when high doses (5 and 10 mM) were used. These in vivo results contribute to increase the database dealing with the potential genotoxic risk associated to SAS nanoparticles exposure. [ABSTRACT FROM AUTHOR]