Assessment of toxic and essential metals in fish feed ingredients available in different areas of Bangladesh

Abstract

Contamination of heavy metals in fish feed ingredients is regarded as a major crisis globally especially in developing countries because it may be the source of toxicity in the food chain. Fish farming in Bangladesh is growing very rapidly and fish available in the markets are mostly coming from fish farms where fish farmers mostly use commercial fish feeds manufacturing with different ingredients. In this study, several types of ingredients based on different origins were collected from several areas and after measuring dry weight these were digested by a mixture of acids. This study is concerned to access the toxic and essential metals in different fish feed ingredients which are frequently used to produce commercial fish feed in Bangladesh. The concentration (mg kg-1 dry weight) range of toxic metals such as; Pb (0.56- 1.73), Cd (0.12-0.97), Cr (0.15-0.88), As (BDL), Hg (BDL), Ni (1.10-2.50) and essential metals such as; Fe (13.57-48.96), Cu (10.11-28.09), Zn (10.60-26.25), Na (12.07-35.00), K (13.06-28.97), Ca (10.00-47.96) in selected fish feed ingredients were recorded by Inductive Coupled Plasma Optical Emission Spectroscopy (ICP-OES, Optima 7000DV) with significant variation (P<0.05). The analyzed toxic and essential metal concentrations in most of the ingredients were within the safe limit proposed by World Health Organization, Food and Agricultural Organization and European Union indicating no health risk.