Browsing by Author "Tavares, Ana M."
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- Exposição a substâncias químicas na indústria da gestão de resíduos elétricos e eletrónicos e seus potenciais efeitos na saúde dos trabalhadoresPublication . Moreira, Rodrigo; Tavares, Ana M.; Louro, Henriqueta; Ventura, Célia; Ladeira, Carina; Viegas, Susana; Silva, Maria JoãoOs resíduos de equipamento elétrico e eletrónico (REEE) são um problema crescente a nível global, sendo considerados um perigo para a saúde humana e ambiental devido à presença de uma variedade de substâncias nocivas, tais como poluentes orgânicos persistentes e metais pesados. Os trabalhadores envolvidos na gestão deste tipo de resíduos estão potencialmente expostos a estas substâncias, particularmente, durante as atividades de reciclagem e processamento. Esta revisão teve por objetivo recolher informação referente à exposição ocupacional a substâncias químicas no sector da gestão de REEE e aos seus potenciais efeitos na saúde dos trabalhadores. A consulta a duas bases de dados (PubMed e Scopus) seguida da aplicação dos critérios de inclusão e exclusão resultou na seleção de 14 estudos que foram sujeitos a uma análise mais detalhada. Os referidos estudos de biomonitorização ocupacional reportaram a exposição dos trabalhadores deste setor a vários metais pesados e compostos orgânicos. A análise de biomarcadores de efeito biológico precoce sugeriu, na maioria dos estudos, uma associação entre a exposição a este tipo de resíduos e alterações hormonais ou genotoxicidade em células sanguíneas. Os referidos efeitos, a confirmarem-se em estudos futuros, poderão traduzir-se a longo termo em patologias, tais como desregulação endócrina ou neoplasias. Em conclusão, embora os estudos revistos sugiram que trabalhar no sector de gestão de REEE representa um potencial risco para os trabalhadores, torna-se necessária a realização de mais estudos de biomonitorização humana, especialmente ao nível europeu, para gerar evidência sólida que apoie medidas de mitigação da exposição desses trabalhadores.
- Hazard characterization of the mycotoxins enniatins and beauvericin to identify data gaps and improve risk assessment for human healthPublication . Behr, Anne-Cathrin; Fæste, Christiane Kruse; Azqueta, Amaya; Tavares, Ana M.; Spyropoulou, Anastasia; Solhaug, Anita; Olsen, Ann-Karin; Vettorazzi, Ariane; Mertens, Birgit; Zegura, Bojana; Streel, Camille; Ndiaye, Dieynaba; Spilioti, Eliana; Dubreil, Estelle; Buratti, Franca Maria; Crudo, Francesco; Eriksen, Gunnar Sundstøl; Snapkow, Igor; Teixeira, João Paulo; Rasinger, Josef D.; Sanders, Julie; Machera, Kyriaki; Ivanova, Lada; Gaté, Laurent; Le Hegarat, Ludovic; Novak, Matjaz; Smith, Nicola M.; Tait, Sabrina; Fraga, Sónia; Hager, Sonja; Marko, Doris; Braeuning, Albert; Louro, Henriqueta; Silva, Maria João; Dirven, Hubert; Dietrich, JessicaEnniatins (ENNs) and beauvericin (BEA) are cyclic hexadepsipeptide fungal metabolites which have demonstrated antibiotic, antimycotic, and insecticidal activities. The substantial toxic potentials of these mycotoxins are associated with their ionophoric molecular properties and relatively high lipophilicities. ENNs occur extensively in grain and grain-derived products and are considered a food safety issue by the European Food Safety Authority (EFSA). The tolerable daily intake and maximum levels for ENNs in humans and animals remain unestablished due to key toxicological and toxicokinetic data gaps, preventing full risk assessment. Aiming to find critical data gaps impeding hazard characterization and risk evaluation, this review presents a comprehensive summary of the existing information from in vitro and in vivo studies on toxicokinetic characteristics and cytotoxic, genotoxic, immunotoxic, endocrine, reproductive and developmental effects of the most prevalent ENN analogues (ENN A, A1, B, B1) and BEA. The missing information identified showed that additional studies on ENNs and BEA have to be performed before sufficient data for an in-depth hazard characterisation of these mycotoxins become available.
- Hazard identification and characterization of leachable chemicals from plastic products – a new PARC projectPublication . Dirven, Hubert; Bogusz, Aleksandra; Hans Bouwmeester; Busch, Mathias; Duflos, Guillaume; Eriksen, Gunnar S.; Fardilha, Margarida; Flores-Gomez, Daniela; Franko, Nina; Gaté, Laurent; Guichard, Yves; Silva, Maria Joao; Kamstra, Jorke H.; Kasiotis, Konstantinos M.; Kim, Sunmi; Kim, Young Jun; Kim, Youngsam; van der Koogh, Elise; Loureiro, Susana; Louro, Henriqueta; Machera, Kyriaki; Pieters, Raymond H. H.; Spyropoulou, Anastasia; Tzanetou, Evangelia N.; Malheiro, Catarina; Ravnjak, Tim; Repetto, Guillermo; Rivière, Gilles; Ryu, Chang Seon; Papadopoulou, Evgenia Anna; Aliferis, Konstantinos A.; Solhaug, Anita; Sollner Dolenc, Marija; Štampar, Martina; Tavares, Ana M.; Tollefsen, Knut Erik; Ventura, Célia; Walkowiak, Radoslaw; Zobl, Walter; Žegura, Bojana; Snapkow, Igor; Herzke, DorteA recent study has suggested that plastics may contain more than 16,000 chemicals, including additives, processing aids, starting substances, intermediates and Non-Intentionally Added Substances. Plastic chemicals are released throughout the plastic life cycle, from production, use, disposal and recycling. Most of these chemicals have not been studied for potential hazardous properties for humans and in the environment. To refine the risk assessment of these leachable chemicals, additional hazard data are needed. The PlasticLeach project within the EU co-funded Partnership for the Assessment of Risks from Chemicals (PARC) aims to address this data gap by screening several plastic products in daily use. Leachates will be prepared from a number of these plastic items, and these chemical mixtures will be further tested using several test guideline compliant assays and New Approach Methodologies covering both human health and environmental endpoints. The most toxic leachates will be characterized using a non-targeted analysis pipeline to identify chemicals in the leachate. When single chemicals of concern are identified, these will be further tested to determine hazardous properties and identify the respective potency factors to better understand their specific hazard profiles. A tiered approach for hazard testing will be followed. The experimental work will be complemented by toxicological profiling, using publicly available toxicity databases and tools, including Artificial Intelligence tools that cover both human and environmental endpoints. A comprehensive array of endpoints, including cytotoxicity, endocrine disruption, genotoxicity, immunotoxicity, reproductive toxicity and effects related to ecotoxicity will be evaluated. In this paper, we outline the plastic products to be tested and the battery of assays that will be used to identify hazards relevant to both human health and the environment. Data generated from approaches will be reported using standardized formats, stored within a centralized repository, and harmonized to adhere to the FAIR data principles (Findable, Accessible, Interoperable, and Reusable). This integrated strategy will not only advance our understanding of the risks associated with plastic-derived chemicals but will also provide critical support for regulatory decision-making and facilitate the development of safer, and more ecofriendly plastic materials in the future.
- In vitro combined toxicity of chromium, nickel and PAHS in human lung cells as support for mixtures risk assessmentPublication . Alves, Inês; Ladeira, Carina; Tavares, Ana M.; Viegas, Susana; Louro, Henriqueta; Silva, Maria JoãoRisk assessment of chemicals mainly relies on exposure to single chemicals and their hazardous effects, although the real scenario in occupational settings is more commonly characterized by exposure to chemi-cal mixtures. Chromium (Cr), Nickel (Ni), and Polycyclic Aromatic Hydrocarbons (PAHs) are often pre-sent in occupational settings, such as aeronautic industries, where workers are exposed primarily through inhalation. Considering that those substances are recognized lung carcinogens acting mainly by genotoxic mechanisms, it is likely that interactive effects occur, indicating that the risk from occupational exposure to these chemicals should be assessed as a mixture. Such issue is being addressed in the HBM4EU Initiati-ve, where a real scenario of occupational exposure has been studied. In order to provide support to the hazard assessment of the referred mixture, the present work aimed to evaluate the combined toxicity of Cr(VI), Ni, and benzo(a)pyrene (BaP), using a human lung cell line (A549 cells). MTT assay was performed for each individual chemical and a dose-response curve was esta-blished, enabling the determination of the IC50. The combined toxicity of the Cr and Ni mixture as well as that of Cr, Ni and BaP were determined comparatively to the single chemicals’ toxicity to ascertain whet-her additive effects or deviations from additivity towards synergism or antagonism was obtained. The results will be presented and discussed and are expected to contribute to the overall mixture’s risk asses-sment.
- Princípios básicos de genotoxicidade e carcinogénesePublication . Louro, Henriqueta; Ventura, Célia; Tavares, Ana M.; Rolo, Dora; Pinto, Fátima; Silva, Maria JoãoA Toxicologia Genética estuda os efeitos adversos de xenobióticos ao nível do genoma dos organismos vivos, procurando compreender a interação gene-ambiente e suas consequências para a saúde humana. O presente curso irá proporcionar aos formandos uma introdução aos conceitos essenciais e às metodologias usadas na área da Toxicologia Genética.