Concentração de íons flúor em águas minerais envasadas no Rio Grande do Sul / Concentration of fluoride ions in mineral water bottled in the state of Rio Grande do Sul

Objetivo: avaliar o nível de flúor presente nas águas minerais carbogasosas e não carbogasosas envasadas no estado do Rio Grande do Sul, comparando os dados com as informações descritas nos rótulos das embalagens. Materiais e método: foram analisadas cinco marcas comerciais de água mineral. Os valores de padrão/ amostra e tampão Tisab foram utilizados em uma relação de 1:1, e as amostras foram lidas em duplicata. As amostras carbogasosas foram agitadas com bastão magnético para eliminação do gás carbônico. Para determinação de flúor, foram utilizados analisador específico de íons, eletrodo seletivo para íon flúor, eletrodo de referência Ag/AgCl de junção simples. Resultados: foram encontradas concentrações de flúor variando entre 0,13 mg F-/L e 1,31 mg F-/L, com diferenças entre os valores estipulados nos rótulos das marcas de água mineral avaliadas e as análises laboratoriais na presente investigação. Os valores de duas marcas de água mineral com flúor analisadas no estudo mostraram-se acima, considerando os valores de referência (0,6-0,8 mg F-/L), e uma marca não apresentou valores de ação preventiva contra a cárie dentária (valores abaixo de 0,6 mg F-/ L). Conclusão: conclui-se que há divergência entre os valores de íons flúor encontrados nas medições e os informados nos rótulos, sendo necessário um sistema de melhor vigilância para o controle dos níveis de flúor nas águas minerais disponibilizadas à população do estado do Rio Grande do Sul, considerando os benefícios do consumo de águas minerais para prevenção dos níveis de cárie na população. (AU)

Objective: quantify the fluoride level in carbogaseous and non-carbogaseous mineral waters bottled in the state of Rio Grande do Sul, Brazil, as well as to compare the data with the information described on the package labels. Materials and method: five brands of mineral water were analyzed. Standard/sample values and Tisab buffer were used in a ratio of 1:1, and the samples were read in duplicates. The carbogaseous samples were shaken with a magnetic rod to eliminate the carbon dioxide. For fluoride determination, a specific ion analyzer was used, as well as a fluoride ion-selective electrode, single-junction Ag/AgCl reference electrode. Results: fluoride concentrations ranging from 0.13 mg F-/L to 1.31 mg F-/L were found, with differences between the values specified in the labels of the mineral water brands evaluated and the laboratory analyses of the present investigation. The values of two brands of mineral water with fluoride analyzed in the study were high, considering the reference values (0.6-0.8 mg F-/L), and one brand did not present values of preventive action against dental caries (below 0.6 mg F-/L). Conclusion: there is a divergence between the values of fluoride ions measured and those reported on the labels, which requires a better surveillance system for controlling fluoride levels in the mineral waters offered to the population of the state of Rio Grande do Sul, Brazil, considering the benefits of mineral water consumption to prevent caries levels in the population. (AU)

Collection and recycling of electronic scrap: a worldwide overview and comparison with the Brazilian situation.

Recycling and the related issue of sustainable development are increasing in importance around the world. In Brazil, the new National Policy on Solid Wastes has prompted discussion on the future of electronic waste (e-waste). Over the last 10 years, different e-waste collection systems and recycling processes have been applied globally. This paper presents the systems used in different countries and compares the world situation to the current Brazilian reality. To establish a recycling process, it is necessary to organize efficient collection management. The main difficulty associated with the implementation of e-waste recycling processes in Brazil is the collection system, as its efficiency depends not only on the education and cooperation of the people but also on cooperation among industrial waste generators, distributors and the government. Over half a million waste pickers have been reported in Brazil and they are responsible for the success of metal scrap collection in the country. The country also has close to 2400 companies and cooperatives involved in recycling and scrap trading. On the other hand, the collection and recycling of e-waste is still incipient because e-wastes are not seen as valuable in the informal sector. The Brazilian challenge is therefore to organize a system of e-waste management including the informal sector without neglecting environmentally sound management principles.