Biomonitoring metallic elements in freshwater fish of Amazon

Abstract

The monitoring of aquatic environments through bioindicators use has been the object of study in several recent works, mainly due to concern over the harmful effects of metallic element levels may cause to aquatic organisms, moreover, and to the risks related with the human consumption of contaminated food. It was measured contents of Cr, Fe and Zn in fish's muscles and gills of seven species of the Amazon region, collected in Piraíba's river situated in Icoaraci district, Belém - Pará. For quantification of Cr it was used a graphite furnace atomic absorption spectrometry (GF AAS) and for quantification for Fe and Zn was used flame atomic absorption spectrometry (FAAS) equipment. The methods validation was developed through of the method of adding and recovery. The contents of Cr obtained were (< 0.19 - 4.93 μg g-1) in muscles, for gills (0.20 - 206.50 μg g-1), for Fe element in the muscle (< 8.00 - 27.00 μg g-1), in gills (< 8.00 - 2130.33 μg g-1), for Zn were obtained (8.93 - 42.39 μg g-1) and in gills (31.30 - 282.36 μg g-1). In the data analysis it was calculated the tolerable weekly ingestion index for the three mineral components; for that, it was applied Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). The results obtained for Cr exceeded limits established by Brazilian Health Surveillance Agency (ANVISA) for human consumption both in muscles and gills. The Zn contents did not exceed values established for muscles and exceed for gills and for Fe the high concentrations were obtained in gills.