Occurrence of trace elements and organochlorine compounds in farmed rainbow trout (Oncorhynchus mykiss)

摘要

Consumption of fish has increased worldwide due to its high nutritional value and health benefit. However, the benefits from fish consumption may be offset by the presence of polychlorinated biphenyls (PCBs), chlorinated pesticides (OClPs), toxic elements, etc.The purpose of this study was to evaluate the presence of trace elements (Hg, As, Cd, Pb, Cu, Fe, Zn, Mn and Se), PCBs (sum of seven individual congeners) and OClPs in thirteen muscle tissues of marketable size rainbow trout.The content of trace elements was determined by atomic absorption spectroscopy (AAS) by applying different techniques: Cu, Zn, Fe and Mn - flame; Cd and Pb - graphite furnace; As and Se - hydride generation; Hg - cold vapor. Of the tested elements, Zn (9.76 mg kg~(-1) ) and Fe (4.76 mg kg"1) had the highest average concentration in fish tissue, followed by Se (0.035 mg kg~(-1) ) and Hg (0.014 mg kg~(-1)). Cd (0.006-0.018 mg kg~(-1)) and Mn (0.94-2.14 mg kg~(-1)) were detected in three, Cu (0.22-1.09 mg kg~(-1)) in six samples, while in the remaining samples concentrations of these elements were above the LD. As and Pb were detected in traces. Statistical analyses of the concentration of elements showed that only between concentration of Fe and Zn (R=0.900) in analyzed fish samples there was significant correlation (at 95% confidence).Quantities of OClPs and PCBs were determined by GC/ECD. Quantities of PCBs and OClPs (except for p,p'-DDE 0.002-0.003 mg kg~(-1)) in all tested samples were above LD of the applied method.