Assessment of trace metal concentrations in Indian Ocean silky sharks Carcharhinus falciformis and their toxicological concerns

This study assessed the concentrations of nine trace metals from juvenile C. falciformis caught from Indian Ocean. This study also discussed the metal pollution index (MPI) and bioconcentration factor (BCF) of each element, and their correlations. Further, the potential health risks of consuming shark muscles (THI) were evaluated. Results showed the mean concentrations of 9 elements as follows: Cu (0.36 +/- 0.17), Zn (5.19 +/- 16.6), Pb (0.12 +/- 0.23), Cd (0.17 +/- 0.21), Cr (0.57 +/- 1.61), Ni (0.086 +/- 0.51), As (1.36 +/- 0.83), Co (0.000073 +/- 0.0074), and V (0.0024 +/- 0.0094) mg/kg ww. The BCF values of the elements were higher than 1, with Co and V being the lowest indicating their bioaccumulative behavior. Correlation analysis showed MPI to be highly correlated with Cu, indicating its greater contributions to the total pollution load. Principal components analysis explained 81.0% of the variability in biometric characteristics and metal concentrations. Health risk assessment for consuming shark muscle in Taiwanese male and female adults suggests potential chronic non-carcinogenic health hazards.