Study of accumulation and human health risk assessment of trace elements in Nile tilapia (Oreochromis niloticus)

Trace elements owing to their bioaccumulation, bio-magnification and higher persistency characteristics have become a major potential risk for aquatic ecosystem worldwide. It is now widely accepted that these trace elements are accumulated in various organs of aquatic organisms and consumption of such animals like fish pose a potential health risk to human. Current study assessed the seasonal (autumn, winter, and spring, summer) accumulation of various trace elements (Cd, Cr, Ni, Pb) in liver, kidney, gills and muscles of Nile tilapia (Oreochromis niloticus) at Abbasia canal Uch Sharif, Punjab, Pakistan. Moreover, health risks associated with the consumption of O. niloticus were also investigated. Three sites (SI, SII, and SIII) of Abbasia canal, 300 m apart, near Uch Sharif, Punjab, Pakistan were sampled for fish collection. The obtained results confirmed a statistical difference (p < 0.05) in accumulation of trace elements in fish organs, seasons and a non-significant difference (p > 0.05) among various sites. Studies trace elements were found in higher concentrations (mu g/g) in liver (6.81 +/- 0.10) and kidney (7.10 +/- 0.20) than gills (6.06 +/- 0.26) and muscles (4.11 +/- 0.24) with an accumulation trend of liver > kidney > gills > muscle. Furthermore, the overall mean accumulation of trace elements in different body tissues were in the order of Pb (8.76 +/- 0.36) > Cd (6.75 +/- 0.15) > Ni (4.93 +/- 0.21) > Cr (3.64 +/- 0.09). The results also concluded that O. niloticus was safe for human consumption as HITE, THQ(TE) and CRTE values for all studied trace elements were within the permissible limits.