Abstract In aquatic habitats, metal contamination from natural and anthropogenic sources continues to pose a concern for human and environmental health. Thus, it is important to complete monitoring studies to assess patterns and the extent of metal contamination in these ecosystems. The purpose of this work was to determine the concentrations of 31 chemical elements and water quality parameters of the Todos os Santos River located in the Mucuri Valley, Minas Gerais, Brazil. A multivariate statistical analysis was used to determine any seasonal and spatial patterns from the data. Results demonstrated that metals including Al, Fe, and Ni exceeded Brazilian and international guidelines nutrients as P also exceed water quality standards. Principal components analysis indicated distinct geographical and seasonal patterns for multiple elements with hierarchical cluster analysis confirming the observed spatial patterns of contamination in the Todos os Santos River.

Este trabalho apresenta a confirmação e otimização do método para derivatização de glifosato e ácido aminometilfosfônico (AMPA) utilizando cloroformiato de 9-fluorenilmetila (FMOC-Cl) avaliando-se os parâmetros: concentração de tampão borato e de FMOC-Cl, tempo de homogeneização e de reação, comprimento de onda e solvente de lavagem. A reação foi promovida com sucesso e o método é simples e de fácil execução pois utiliza cinco minutos de homogeneização e permite análises no ultravioleta imediatamente após o fim da reação.

This work presents the confirmation and optimization of the method for derivatization of glyphosate and aminomethylphosphonic acid (AMPA) using 9-fluorenylmethyl chloroformate (FMOC-Cl) evaluating the parameters: concentration of borate buffer and FMOC-Cl, homogenization time and of reaction, wavelength and solvent washing. The reaction was successfully promoted and the method is simple and easy to perform because it uses five minutes of homogenization and allows ultraviolet analysis immediately after the end of the reaction.