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The activated carbon filter is used in residences as another step in the treatment of drinking water, based on a physical-chemical process to absorb pollutants that are not removed in conventional treatment. Endocrine disruptors (EDCs) are exogenous substances or mixtures of substances that acts on the endocrine system similarly to the endogenously produced hormones, triggering malfunctions and harmful changes to human and animal health. The objective of the present work was to study EDCs through semi-quantitative analysis of residential water filters collected in the region of Rio dos Sinos basin, focusing on two specific classes: hormones and phenols. The solid phase extraction principle was used for the extraction of compounds and gas chromatography coupled with mass spectrometry for the separation and characterization of EDCs. Four samples of residential filters collected from public water distribution and artesian wells, from the cities of Novo Hamburgo and São Leopoldo were analysed. Using the developed methodology, it was possible to detect and comparatively quantify selected EDCs in all studied samples, which indicates the presence of these contaminants in drinking water from different sources.Keywords: charcoal filters, EDCs, POPs, phenols, endocrine disruptors. Disruptores endócrinos em filtros de água utilizados na região da Bacia Hidrográfica do Rio dos Sinos no Sul do BrasilResumo O filtro de carvão ativado é utilizado em residências como mais uma etapa no processo de tratamento da água potável, tendo como base um processo físico-químico para adsorção de poluentes presentes na água que não são removidos no tratamento convencional. Os Disruptores Endócrinos (DEs) são substâncias ou misturas exógenas que atuam no sistema endócrino de maneira similar aos hormônios produzidos endogenamente, desencadeando disfunções e alterações nocivas à saúde humana e animal. O objetivo do presente trabalho foi estudar DEs através da análise semi-quantitativa de amostras de filtros de água coletados na região da bacia do Rio dos Sinos focando em duas classes químicas: hormômios estrogênicos e fenóis. Foram utilizados os princípios da técnica de extração em fase sólida (SPE) para a extração dos compostos, e cromatografia gasosa acoplada à espectrometria de massas para a separação e detecção de DEs. Foram analisadas quatro amostras de filtros residenciais provenientes de água tratada e água de poço artesiano, das cidades de Novo Hamburgo e São Leopoldo. Com o método desenvolvido foi possível detectar e quantificar comparativamente DEs selecionados em todas as amostras estudadas, o que indica a presença desses contaminantes na água de consumo humano oriunda de diferentes fontes.Palavras-chave: filtro de carvão ativo, DEs, POPs, fenóis e disruptores endócrinos.

Abiraterone acetate efficacy against prostate cancer is dependent on the circulating levels of abiraterone and its active metabolites, which present significant pharmacokinetic variability among patients. Thus, therapeutic drug monitoring can be performed to improve treatment outcomes. To support such studies, there are only a limited number of bioanalytical methods in current literature. This work presents a fast method to quantify abiraterone and D4A in plasma in 4 min by UPLC-MS/MS. Bioanalytical method validation was performed according to the recommendations of the US Food and Drug Administration. The method was linear within the range of 1-400 ng/ml for abiraterone and 0.2-20 ng/ml for D4A (r 2 > 0.99). Based on the analysis of quality control samples at the lower limit of quantification, low, medium and high concentrations, the method was precise (CV abiraterone ≤ 9.72%; CV D4A ≤ 14.64%) and accurate (CV abiraterone 95.51-107.59%; CV D4A 98.04-99.89%). Application of the method to the quantification of abiraterone and D4A in 10 clinical samples revealed important variability in the conversion ratio of abiraterone to D4A (CV 90.85%). Considering the current literature, this is the fastest method to quantify abiraterone and D4A in plasma, allowing for optimization of the analytical routine. K E Y W O R D S abiraterone, bioanalytical method validation, D4A, therapeutic drug monitoring, UPLC-MS/MS 1 | INTRODUCTION Abiraterone [17-(3-pyridyl)-androsta-5,16-dien-3β-ol, C 24 H 31 NO], administered as the pro-drug abiraterone acetate, is an androgen synthesis inhibitor used to treat castration-resistant prostate cancer. The standard dose is 1,000 mg/day taken in fasted state in association with prednisone 10 mg/day (FDA, 2011). Clinical studies have provided evidence for the variable efficacy of treatment