Abstract Access to safe drinking water is a fundamental human right and a critical component of sustainable development. This study is conducted in the context of the Taquari-Antas Hydrographic Basin, Rio Grande do Sul, Brazil, and assesses the quality of drinking water in 101 rural properties, focusing on identifying problems of potability, especially regarding excessive fluoride concentration, which is a known problem for the water in this region. The study involves the collection of water samples from rural properties, a survey to understand water use and quality perception by users, and water quality analysis using established analytical methodologies. Results show that 58.4% of the investigated rural properties have potability issues, with excessive fluoride being the most prevalent concern, affecting 39.6% of properties. High fluoride levels have significant health implications, including dental and skeletal fluorosis, with global relevance. To address this issue, activated bone charcoal filtration systems were installed in ten properties, effectively reducing fluoride concentrations to within acceptable limits for human consumption. These defluoridation systems are characterized as sustainable, cost-effective, and scalable, offering a practical solution for regions facing similar challenges. development TaquariAntas Taquari Antas Basin Sul Brazil 10 concentration region users methodologies 584 58 4 58.4 issues concern 396 39 6 39.6 implications fluorosis relevance issue consumption costeffective, costeffective cost effective, effective cost-effective scalable challenges 1 5 58. 3 39.

Resumo O acesso à água potável segura é um direito humano fundamental e um componente crítico do desenvolvimento sustentável. Este estudo foi realizado no contexto da Bacia Hidrográfica Taquari-Antas, no Rio Grande do Sul, Brasil, e avalia a qualidade da água para consumo em 101 propriedades rurais, com foco na identificação de problemas em sua potabilidade, especialmente em relação à concentração excessiva de flúor, que é um problema conhecido na água desta região. O estudo envolve a coleta de amostras de água em propriedades rurais, uma pesquisa para compreender o uso da água e a percepção da qualidade pelos usuários, e análises da qualidade da água utilizando metodologias analíticas estabelecidas. Os resultados mostram que 58,4% das propriedades rurais investigadas apresentam problemas de potabilidade, sendo o excesso de flúor a preocupação mais prevalente, afetando 39,6% das propriedades. Altos níveis de flúor têm implicações significativas para a saúde, incluindo fluorose dentária e esquelética, com relevância global. Para enfrentar esse problema, sistemas de filtração com carvão ativado de osso foram instalados em dez propriedades, reduzindo eficazmente as concentrações de flúor para níveis aceitáveis para consumo humano. Esses sistemas de defluoretação são caracterizados como sustentáveis, economicamente viáveis e escaláveis, oferecendo uma solução prática para regiões que enfrentam desafios semelhantes. sustentável TaquariAntas, TaquariAntas Taquari Antas, Antas Taquari-Antas Sul Brasil 10 potabilidade região usuários estabelecidas 584 58 4 58,4 prevalente 396 39 6 39,6 saúde esquelética global sustentáveis escaláveis semelhantes 1 5 58, 3 39,

This article describes the development of a mobile colorimetric analysis tool. The application, called PhotoMetrix, employs the techniques of simple linear correlation for univariate analysis and principal components analysis (PCA) for multivariate exploratory analysis. The image data are captured by the main camera of the device and converted into red, green and blue (RGB) histograms. As regards the application, the iron determinations were performed in vitamin supplements (univariate module) and differentiation of banknotes was performed by PCA (multivariate module). For the iron determinations, three samples of vitamins at concentrations of 14, 40 and 50 mg of iron per tablet were tested and the results were not statistically significant (p > 0.05) compared to the reference method. The differentiation of banknotes was performed on Brazilian and Argentinean banknotes. The results showed clustering of the same types of banknotes, and through the loadings graph it was possible to observe the variables through the formation of clusters.