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Flame retardants, crucial for fire prevention, are used worldwide, but they are considered to be 'emerging contaminants' and may pose risks to human and environmental health. Aluminum diethyl phosphinate (ALPI) is a halogen-free flame retardant. To evaluate the toxicity of this compound, the following assays were performed: Salmonella/microsome mutagenicity assay; toxicity assays with two endpoints (mitochondrial dehydrogenase activity, plasma membrane integrity); micronucleus assay with human hepatoma cell line HepG2. ALPI was not mutagenic in Salmonella strains TA97, TA98, TA100, TA102, or TA104. ALPI was not cytotoxic at any concentration tested. The HepG2 micronucleus assay showed genotoxicity of ALPI at 200 µg/mL and no cytotoxicity (cytokinesis-block proliferation index, CBPI). Our data are relevant to the regulation of flame retardants., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. Israel Felzenszwalb reports financial support was provided by State University of Rio de Janeiro Biomedical Centre. Israel Felzenszwalb reports financial support was provided by Carlos Chagas Filho Foundation for Research Support of Rio de Janeiro State. Israel Felzenszwalb reports financial support was provided by National Council for Scientific and Technological Development. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

During the coffee beans roasting process, occurs the formation of polycyclic aromatic hydrocarbons, which are associated with the incidence of cancer in humans. This study aimed to evaluate the influence of coffee bean quality and roasting degree regarding mutagenicity, cytotoxicity and genotoxicity. Six samples of coffee drink made with roasted and ground Coffea arabica beans from different qualities and roast degrees were used after freeze-drying. Both commercial and special quality grains suffered light, medium and dark roasting. According to the Salmonella/microsome assay, the highest concentration of commercial grain sample (dark roast) significantly increased the number of revertants of the TA98 strain in the absence of metabolization. All the samples induced cytotoxicity to HepG2 cells. These effects can be ranked in the following order from most to least toxic: medium roast - special grain > light roast - special grain > dark roast - commercial grain > dark roast - special grain > light roast - commercial grain > medium roast - commercial grain. None of the samples induced genotoxicity in HepG2 cells. Our findings show that the harmful effects of coffee depend not only on the degree of roasting but also on the grain quality., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

3D Cell culture is an alternative to animal use in many drug development and toxicity studies. The 3D cell culture can mimic and reproduce the original tissue microenvironment, morphology, and mechanical and physiological characteristics, to provide a more realistic and reliable response as compared to two-dimensional cultures. 3D cell culture encapsulated in alginate beads is a very simple and relatively inexpensive tool that is easy to handle and to maintain. The alginate beads function as a scaffold that imprisons cells and allows 3D cell growth, to generate spheroids that can have greater genic expression and cell-cell communication as a nano or microtissue. The HepG2 cell line is a human hepatocellular carcinoma cell derivative. HepG2 cells preserve several of the characteristics of hepatocytes and are therefore often used in toxicity studies. Here, we describe HepG2 cell encapsulation in alginate beads and analyze the resulting spheroids formed within the alginate beads by immunocytochemistry, by staining a certain structure with a specific antibody coupled with a fluorophore. This method preserves the beads and enables cell analysis by confocal microscopy.

Background: Ultraviolet (UV) radiation is the main exogenous inductor of skin damage and so photoprotection is important to control skin disorders. The Antarctic moss Sanionia uncinata is an important source of antioxidants and the photoprotective activity of its organic extracts has been investigated. This study aimed to evaluate the potential photoprotection, cytotoxicity and embryotoxicity of residual aqueous fraction (AF) from the moss S. uncinata., Methods: UV-visible spectrum and SPF (sun protection factor) were determined by spectrophotometry. Embryotoxicity potential was evaluated by Fish embryo-larval toxicity test using zebrafish (Danio rerio) as organism model. Cell death assays by water-soluble tetrazolium salt (WST-1) and lactate dehydrogenase (LDH) were investigated using HaCaT keratinocyte cell line cultured in monolayers and three dimensions (3D). Phototoxicity and association with UV-filters were performed by 3T3 neutral red uptake test., Results: The AF showed sharp absorption bands in the UV region and less pronounced in the visible region. The SPF was low (2.5 ± 0.3), but the SPF values of benzophenone-3 and octyl-methoxycinnamate increased ~ 3 and 4 times more, respectively, in association with AF. The AF did not induce significant lethal and sublethal effects on zebrafish early-life stages. In monolayers, the HaCaT cell viability, evaluated by WST-1, was above 70% by ≤0.4 mg AF/mL after 48 and 72-h exposure, whereas ≤1 mg AF/mL after 24-h exposure. The LDH assay showed that the cell viability was above 70% by ≤0.4 mg AF/mL even after 72-h exposure, but ≤1 mg/mL after 24 and 48-h exposure. In 3D cell culture, an increased cell resistance to toxicity was observed, because cell viability of HaCaT cell by WST-1 and LDH was above ~ 90% when using ≤1 and 4 mg AF/mL, respectively. The AF demonstrated values of photo irritation factor < 2 and of photo effect < 0.1, even though in association with UV-filters., Conclusions: The residual AF absorbs UV-vis spectrum, increased SPF values of BP-3 and OMC and does not induce embryotoxicity to zebrafish early life-stage. The cell death assays allowed establishing non-toxic doses of AF and phototoxicity was not detected. AF of S. uncinata presents a good potential for skin photoprotection against UV-radiation.

This study aimed to optimize Cymbopogon citratus essential oil loaded into PLGA-nanoparticles by investigating the effect of processing variables (sonication time, ultrasound power, and essential oil/polymer ratio) on encapsulation efficiency and particle mean hydrodynamic diameter using Box-Behnken design. Nanoparticles were prepared by an emulsification/solvent diffusion method and physicochemically characterized by FTIR, DSC and TGA/DTA. Cytotoxicity was evaluated in human HaCat keratinocytes by WST-1 and LDH assays. The optimized formulation had a hydrodynamic mean diameter of 277 nm, a polydispersity index of 0.18, a Zeta potential of -16 mV and an encapsulation efficiency of 73%. Nanoparticle characterization showed that only citral was incorporated in nanocarriers, with some amount adsorbed on their surface, and highlighted the potential in increasing the oil thermal stability. The drug release profile demonstrated a biphasic pattern with a substantial sustained release depending on diffusion from the polymeric matrix. Toxicity effects on cell viability of pure essential oil at low concentrations were significantly eliminated when encapsulated. Results revealed the ability of PLGA-nanoparticles to improve essential oil physicochemical characteristics, by controlling release and reducing toxicity, suggesting their potential use in pharmaceutical preparations., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Nail polish has been widely used around the world. However, the hazards of nail polishes discarded in the environment are still poorly investigated. Thus, the toxicogenetic effects of solubilized (SE) and leached (LE) extracts from nail polishes were investigated, simulating their disposal on water and landfill, respectively, and identifying their physicochemical properties and chemical constituents. Organic compounds and metals were detected in both extracts. SE and LE only induced mutagenic effects in TA98 Salmonella strain in the presence and absence of exogenous metabolic activation. Although both extracts did not significantly increase the frequency of micronucleated HepG2 cells, the cell viability was affected by 24-h exposure. No DNA damage was observed in gonad fish cells (RTG-2) exposed to both extracts; however, the highest SE and LE concentrations induced significant lethal and sublethal effects on zebrafish early-life stages during 96-h exposure. Based on our findings, it can be concluded that if nail polishes enter aquatic systems, it may cause negative impacts to the environment.

Amazon mosses, such as Holomitriopsis laevifolia and Leucobryum sp. are naturally exposed to high levels of solar ultraviolet (UV) radiation. Theoretically, under environmental stress conditions these mosses have developed protective chemical and metabolic strategies against UV damage, by way of biosynthesis of secondary metabolites, such as flavonoids. The present paper aimed to evaluate the free-radical scavenging activity, and the photoprotective, mutagenic and photomutagenic potencies of the methanolic (ME), aqueous (AE), hydroalcoholic (HE), ethanolic (EE) extracts of H. laevifolia and Leucobryum sp. The phenolic contents were evaluated by spectrophotometry and by High-Performance Liquid Chromatography (HPLC). The present findings showed that the AE and HE of H. laevifolia and the AE of Leucobryum sp. presented the highest phenolic contents. The HPLC analysis indicated the presence mainly of phenolic and cinnamic acids, flavonols, flavones and flavanones. The AE and EE of H. laevifolia and the AE and HE of Leucobryum sp. efficiently scavenged the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical. All extracts showed significant values of in vitro Sun Protection Factor alone, and HE of Leucobryum sp. showed a synergistic effect in association with benzophenone-3. None of the extracts induced mutagenicity in the auxotrophic strains for histidine of Salmonella typhimurium, and photomutagenicity of the TA102 and TA104 strains was not detected after exposure to UV-A radiation. Besides, all extracts showed photoprotective activity against UV-A radiation for the TA104 strain, including synergistic protection in association with BP-3. Thus, the constituents in H. Laevifolia and Leucobryum sp. could be good candidates for cosmetic and dermatological applications, particularly in association with synthetic UV filters, since the concentration of the filters in the final product could be reduced., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Coffee is one of the most widely consumed beverages throughout the world. So far, many studies have shown the properties of coffee beverages, but little is known about its impacts on human and environmental health from its discard in the environment. So, the present work aims to investigate the mutagenic, genotoxic, cytotoxic and ecotoxic effects of leached (LE) and solubilized (SE) extracts from coffee waste, simulating the disposal of this residue in landfills and via sewage systems, respectively. Chemical analyses were also carried out. LE and SE induced mutagenicity in the TA98 Salmonella strain with and without exogenous metabolization (S9). In the TA100 only SE induced mutagenicity, what was observed without S9. An increase in the frequency of micronuclei was observed in HepG2 cell line after 3 and 24h of exposure to both extracts. No cytotoxic effects were observed in HepG2 cells by WST-1 assay. The EC50 values for the LE and SE were 1.5% and 11.26% for Daphnia similis, 0.12% and 1.39% for Ceriodaphnia dubia and 6.0% and 5.5% for Vibrio fischeri, respectively. Caffeine and several transition metals were found in both extracts. Coffee waste discarded in the environment may pose a risk to human and environmental health, since this compound can cause DNA damage and present toxicity to aquatic organisms., (Copyright © 2017 Elsevier Inc. All rights reserved.)