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High-energy industrial processes have been associated with particle release into workplace air that can adversely affect workers' health. The present study assessed the toxicity of incidental fine (PGFP) and nanoparticles (PGNP) emitted from atmospheric plasma (APS) and high-velocity oxy-fuel (HVOF) thermal spraying. Lactate dehydrogenase (LDH) release, 2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate (WST-1) metabolisation, intracellular reactive oxygen species (ROS) levels, cell cycle changes, histone H2AX phosphorylation (γ-H2AX) and DNA damage were evaluated in human alveolar epithelial cells at 24 h after exposure. Overall, HVOF particles were the most cytotoxic to human alveolar cells, with cell viability half-maximal inhibitory concentration (IC50) values of 20.18 µg/cm2 and 1.79 µg/cm2 for PGFP and PGNP, respectively. Only the highest tested concentration of APS-PGFP caused a slight decrease in cell viability. Particle uptake, cell cycle arrest at S + G2/M and γ-H2AX augmentation were observed after exposure to all tested particles. However, higher levels of γ-H2AX were found in cells exposed to APS-derived particles (~16%), while cells exposed to HVOF particles exhibited increased levels of oxidative damage (~17% tail intensity) and ROS (~184%). Accordingly, APS and HVOF particles seem to exert their genotoxic effects by different mechanisms, highlighting that the health risks of these process-generated particles at industrial settings should not be underestimated., This research was funded by the project CERASAFE with the support of ERA-NET SIINN (project id:16) and the Portuguese Foundation for Science and Technology (FCT; SIINN/0004/2014). This work was also supported by the project NanoBioBarriers (PTDC/MED-TOX/31162/2017), co-financed by the Operational Program for Competitiveness and Internationalization (POCI) through European Regional Development Funds (FEDER/FNR) and FCT and the Spanish Ministry of Science and Innovation (projects PCIN-2015-173-C02-01 and CEX2018-000794-S-Severo Ochoa). M.J. Bessa (SFRH/BD/120646/2016) and F. Brandão (SFRH/BD/101060/2014) are recipients of FCT PhD scholarships under the framework of the Human Capital Operating Program (POCH) and European Union funding. The Doctoral Program in Biomedical Sciences of the ICBAS—University of Porto offered additional funds. S. Fraga thanks FCT for funding through program DL 57/2016—Norma transitória (Ref. DL-57/INSA-06/2018). Thanks are also due to FCT/MCTES for the financial support to EPIUnit and ITR (UIDB/04750/2020 and LA/P/0064/2020).

Diverse industries have already incorporated within their production processes engineered nanoparticles (ENP), increasing the potential risk of worker inhalation exposure. In vitro models have been widely used to investigate ENP toxicity. Air-liquid interface (ALI) cell cultures have been emerging as a valuable alternative to submerged cultures as they are more representative of the inhalation exposure to airborne nano-sized particles. We compared the in vitro toxicity of four ENP used as raw materials in the advanced ceramics sector in human alveolar epithelial-like cells cultured under submerged or ALI conditions. Submerged cultures were exposed to ENP liquid suspensions or to aerosolised ENP at ALI. Toxicity was assessed by determining LDH release, WST-1 metabolisation and DNA damage. Overall, cells were more sensitive to ENP cytotoxic effects when cultured and exposed under ALI. No significant cytotoxicity was observed after 24 h exposure to ENP liquid suspensions, although aerosolised ENP clearly affected cell viability and LDH release. In general, all ENP increased primary DNA damage regardless of the exposure mode, where an increase in DNA strand-breaks was only detected under submerged conditions. Our data show that at relevant occupational concentrations, the selected ENP exert mild toxicity to alveolar epithelial cells and exposure at ALI might be the most suitable choice when assessing ENP toxicity in respiratory models under realistic exposure conditions., This research was funded by CERASAFE (www.cerasafe.eu; accessed on 26 October 2021), with the support of ERA-NET SIINN (project id:16) and the Portuguese Foundation for Science and Technology (FCT; SIINN/0004/2014). This work was also supported by the NanoBioBarriers project (PTDC/MED-TOX/31162/2017), co-financed by the Operational Program for Competitiveness and Internationalization (POCI) through European Regional Development Funds (FEDER/FNR) and FCT; Spanish Ministry of Science and Innovation (projects PCIN-2015-173-C02-01 and CEX2018-000794-S-Severo Ochoa), and by the Romanian National Authority for Scientific Research and Innovation (CCCDI-UEFISCDI, project number 29/2016 within PNCDI III). M.J. Bessa (SFRH/BD/120646/2016) and F. Brandão (SFRH/BD/101060/2014) are recipients of FCT PhD scholarships under the framework of Human Capital Operating Program (POCH) and European Union funding. The Doctoral Program in Biomedical Sciences, of the ICBAS—University of Porto, offered additional funds. S. Fraga thanks FCT for funding through program DL 57/2016–Norma transitória (Ref. DL-57/INSA-06/2018). Thanks are also due to FCT/MCTES for the financial support to EPIUnit (UIDB/04750/2020).

Objective: to determine whether Cyt-B could interfere with micronuclei (MN) induction by TiO2 NP in human SH-SY5Y cells, as assessed by CBMN test. info:eu-repo/semantics/publishedVersion

The advanced ceramic technology has been pointed out as a potentially relevant case of occupational exposure to nanoparticles (NP). Not only when nanoscale powders are being used for production, but also in the high-temperature processing of ceramic materials there is also a high potential for NP release into the workplace environment. In vitro toxicity of engineered NP (ENP) [antimony tin oxide (Sb2O3•SnO2; ATO); zirconium oxide (ZrO2)], as well as process-generated NP (PGNP), and fine particles (PGFP), was assessed in MucilAir™ cultures at air-liquid interface (ALI). Cultures were exposed during three consecutive days to varying doses of the aerosolized NP. General cytotoxicity [lactate dehydrogenase (LDH) release, WST-1 metabolization], (oxidative) DNA damage, and the levels of pro-inflammatory mediators (IL-8 and MCP-1) were assessed. Data revealed that ENP (5.56 µg ATO/cm2 and 10.98 µg ZrO2/cm2) only caused mild cytotoxicity at early timepoints (24 h), whereas cells seemed to recover quickly since no significant changes in cytotoxicity were observed at late timepoints (72 h). No meaningful effects of the ENP were observed regarding DNA damage and cytokine levels. PGFP affected cell viability at dose levels as low as ∼9 µg/cm2, which was not seen for PGNP. However, exposure to PGNP (∼4.5 µg/cm2) caused an increase in oxidative DNA damage. These results indicated that PGFP and PGNP exhibit higher toxicity potential than ENP in mass per area unit. However, the presence of a mucociliary apparatus, as it occurs in vivo as a defense mechanism, seems to considerably attenuate the observed toxic effects. Our findings highlight the potential hazard associated with exposure to incidental NP in industrial settings.

Several reports on amorphous silica nanomaterial (aSiO₂ NM) toxicity have been questioning their safety. Herein, we investigated the in vivo pulmonary toxicity of four variants of aSiO₂ NM: SiO₂_15_Unmod, SiO₂_15_Amino, SiO₂_7 and SiO₂_40. We focused on alterations in lung DNA and protein integrity, and gene expression following single intratracheal instillation in rats. Additionally, a short-term inhalation study (STIS) was carried out for SiO₂_7, using TiO₂_NM105 as a benchmark NM. In the instillation study, a significant but slight increase in oxidative DNA damage in rats exposed to the highest instilled dose (0.36 mg/rat) of SiO₂_15_Amino was observed in the recovery (R) group. Exposure to SiO₂_7 or SiO₂_40 markedly increased oxidative DNA lesions in rat lung cells of the exposure (E) group at every tested dose. This damage seems to be repaired, since no changes compared to controls were observed in the R groups. In STIS, a significant increase in DNA strand breaks of the lung cells exposed to 0.5 mg/m³ of SiO₂_7 or 50 mg/m³ of TiO₂_NM105 was observed in both groups. The detected gene expression changes suggest that oxidative stress and/or inflammation pathways are likely implicated in the induction of (oxidative) DNA damage. Overall, all tested aSiO₂ NM were not associated with marked in vivo toxicity following instillation or STIS. The genotoxicity findings for SiO₂_7 from instillation and STIS are concordant; however, changes in STIS animals were more permanent/difficult to revert. CA extern

About adequacy of the standardised in vitro mammalian cell Micronucleus (MN) test for nanomaterials genotoxicity testing. info:eu-repo/semantics/publishedVersion

Background, Motivation and Objective: The need to assess the toxicity resulting from exposure to mixtures of chemicals has been recognized by the WHO and EU, as humans are simultaneously exposed to an array of natural and anthropogenic contaminants. Of particular interest are the potential combined effects resulting from interaction of nanoparticles (NPs) and metals. While the first are the current driving force for emerging contaminants, the latter, as legacy contaminants, remain a concern. Metals show strong affinity to NPs, which can change the uptake and toxicity to the organism of each individual contaminant. Studying the effects on the respiratory tract is of upmost relevance because of its constant contact with xenobiotics, resulting in adverse effects on the lung. Considering the above, the objective of this work was to assess and compare viability, cell cycle, and uptake of A549 cells after exposure to single and binary mixtures of titanium dioxide nanoparticles (TiO2NP), cerium oxide nanoparticles (CeO2NP), arsenic (As) and mercury (Hg). These chemicals were chosen because: 1) TiO2NP are among the most abundantly used NPs; 2) CeO2NP have been used in nanomedicine for its high biocompatibility and cytoprotective effect; and 3) As and Hg due to their non‐biodegradable, persistent, and extremely toxic character. This work intends to support adequate human risk assessment resulting from co-exposure to multiple contaminants. NanoLegaTox (PTDC/SAU-PUB/29651/2017) cofinanced by COMPETE2020, Portugal2020 and European Union, through FEDER. A.T.Reis, F.Brandão and M.J.Bessa financed by FCT Grants SFRH/BPD/122112/2016, SFRH/BD/101060/2014 and SFRH/BD/12046/2016. A.C.Estrada and C.B.Lopes funded by national funds (OE), in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of article 23, Decree-Law 57/2016, August 29, changed by Law 57/2017, July 19. info:eu-repo/semantics/publishedVersion

Iron oxide nanoparticles (ION) have attracted much attention in last decade for their utility in several biomedical applications such as magnetic resonance imaging, hyperthermia-based cancer therapy, and targeted drug/gene delivery. Particularly, previous works showed that ION can cross the blood-brain barrier, making them especially useful as diagnostic and therapeutic tools, specifically in central nervous system diseases (reviewed in Kiliç et al., 2017). Although oleic acid-coated ION (O-ION) show in general good stability and biocompatibility, toxicological studies about their effect in human nervous cells are scant so far. Neurotoxicity assessment is therefore crucial to establish safety conditions for O-ION biomedical uses. Hence, the main objective of this work was to assess the potential genotoxic damage induced on human glial cells (A172 astrocytes) by exposure to O-ION. Xunta de Galicia (ED431B 2019/02), Ministerio de Educación, Cultura y Deporte (BEAGAL18/00142 to V.), Deputación Provincial de A Coruña (to N.F.-B.), and FCT (subsidized by national fund of MCTES, SFRH/BD/101060/2014 [to F.B.]). Authors would also like to acknowledge COST Action CA15132 “The comet assay as a human biomonitoring tool (hCOMET)”. N/A

This study aimed to investigate the in vitro toxicity of engineered (ENP) and airborne ceramic NP in a 3D human bronchial epithelial model (MucilAir™) under air-liquid interface conditions. This work was supported by the Portuguese Foundation for Science and Technology (FCT) through the CERASAFE project (SIINN/0004/2014). MJB and FB are recipients of FCT PhD scholarships (SFRH/BD/120646/2016 and SFRH/BD/101060/2014). info:eu-repo/semantics/draft

The in vitro cytokinesis-block micronucleus cytome assay (CBMN) is widely used for genotoxicity evaluation of nanomaterials (NMs). However, cytochalasin-B (Cyt-B) used in this test may affect the uptake of NMs due to possible interference with endocytosis. Thus, the aim of this study was to investigate the influence of Cyt-B on the uptake of TiO2 nanoparticles (TiO2 NPs) by four different human cell lines: lung cells (A549), glial cells (A172), neurons (SH-SY5Y), and liver cells (HepG2). This work was supported by Xunta de Galicia (reference ED431B 2016/013). F. Brandão is supported by the grant SFRH/BD/101060/2014, funded by FCT (subsidized by national fund of MCTES) and V. Valdiglesias by a Xunta de Galicia postdoctoral fellowship (reference ED481B 2016/190-0). N/A

Several ceramic industries have already incorporated within their production processes the manufacture of different types of ceramic nanoparticles (NPs), as well as the application of those nanomaterials on conventional products, which increases the risk of human exposure to these nanoparticles, particularly in occupational settings. The aim of this study was to investigate the in vitro toxicity of ceramic NPs (ZrO2, CeO2 and Sb2O3•SnO2 NPs) in human alveolar epithelial cells, a primary target following inhalation exposure. This work was supported by the FCT through the CERASAFE project (SIINN/0004/2014). Session 5 N/A

The toxicological assessment of the potential toxicity of manufactured nanomaterials (MNMs) is urgently needed due to their increased use for commercial and industrial applications. Thus, this study evaluated the cyto- and genotoxicity of a panel of MNMs, including SiO2 NPs, graphene oxide, and nano-sized pigments in rat alveolar epithelial cells (RLE-6TN), a primary target during inhalation exposure. This work was supported by FCT through the ERA-NET SIINN project NanoToxClass (ERA-SIINN/0001/2013). N/A

Nanotechnology offers many possibilities in the ceramic sector by providing innovation of the industrial processes and products. However, nanoparticles (NPs) used in the manufacture of ceramic goods or released to the workplace air during production may pose a serious hazard for human health. This study aimed to investigate in vitro toxicity of both engineered (ENPs) (ZrO2, CeO2, SnO2 and Sb2O3•SnO2) and process-generated nanoparticles (PGNPs) [released during High Velocity Oxy-Fuel (HVOF) spraying] in human alveolar epithelial cells, a primary target following inhalation exposure. This work was supported by the FCT through the CERASAFE project (SIINN/0004/2014). N/A

Main goal: The aim of this study was to evaluate the cyto- and genotoxicity of a panel of MNMs, including SiO2 NPs, graphene oxide, and nano-sized pigments in rat alveolar epithelial cells (RLE-6TN), a primary target following inhalation exposure. This work was supported by Fundação para a Ciência e a Tecnologia through European project NanoToxClass (ERA-SIINN/0001/2013). FB, CC and MJB are recipients of FCT fellowships (SFRH/BD/101060/2014, SFRH/BPD/96196/2013 and SFRH/BD/120646/2016). N/A

Submitted by Rosa Duarte (rduarte@maieutica.ismai.pt) on 2020-06-18T14:57:55Z No. of bitstreams: 1 Tese Fátima de Jesus Brandão.pdf: 278486 bytes, checksum: 7d17d11e4c53f22385c5bcbb140c891c (MD5) Made available in DSpace on 2020-06-18T14:57:55Z (GMT). No. of bitstreams: 1 Tese Fátima de Jesus Brandão.pdf: 278486 bytes, checksum: 7d17d11e4c53f22385c5bcbb140c891c (MD5) Previous issue date: 2018-06 N/A

The aim of this study was to investigate the in vitro toxicity of three ceramic nanoparticles in A549 cell line, a primary target during inhalation exposure. N/A

Recebeu o prémio de Melhor Comunicação Oral do Congresso The rapid development of manufactured nanomaterials (MNMs) and their increased use for commercial and industrial applications lead to the urgent need of the toxicological assessment of their potential toxicity. Thus, this study evaluated the cyto- and genotoxicity of a panel of MNMs, including SiO2 nanoparticles (NPs), graphene oxide and nano-sized pigments in rat alveolar epithelial cells (RLE-6TN), a primary target during inhalation exposure. This study was funded by Fundação para a Ciência e a Tecnologia (FCT) through ERA-NET SIINN project NanoToxClass (ERA-SIINN/0001/2013). FB, CC and MJB are recipients of FCT fellowships (SFRH/BD/101060/2014, SFRH/BPD/96196/2013 and SFRH/BD/120646/2016). N/A