Técnicas analíticas para determinação de nutrientes e metais pesados em águas do rio Guamá e afluentes e solos de Caxiuanã

Abstract

The human occupation of natural areas leads to the discharge of various substances into the environment, some of which have extremely harmful effects, the most noticeable being the degradation of water quality and diseases. Substances such as heavy metals, even in small concentrations, can have worrying effects because they are extremely toxic and have a cumulative effect. As water is the natural resource most consumed by humans, it is necessary to know if it is being used within the desirable quality standards for human consumption. Therefore, it is essential to identify the potentially polluting sources of water in order to make it suitable for consumption. The proposal of this work is the development of a methodology in chemical analysis for the determination of heavy metals in waters of the Guamá River and its tributaries and also the interpretation of the results obtained, relating them to changes in aquatic ecosystems. Monitoring was carried out in pre-established points along the chosen area, and the classic methodology for the determination of heavy metals using the atomic absorption apparatus was initially applied. The analyses did not detect the presence of the metals, because the sensitivity of the apparatus was not sufficient to detect the presence of these metals, which are in extremely low concentrations in surface waters. A new methodology, based on a pre-concentration with activated carbon, is being developed, so that the metals can be in detectable concentrations by the atomic absorption apparatus. The chemical analyses as well as the discussion of the results obtained by the new method are still in progress.