The levels of Arsenic (As), Cadmium (Cd), Chromium (Cr) and Lead (Pb) referred to as the quaternary
heavy metals (QHMs) were investigated in fish tissues (gill, stomach, intestine and liver) of Tilapia
gallier, Clarias lazera and Heterotis niloticus caught from Lake Alau, Nigeria with the aim of presenting
the QHMs interaction profile and hence provide further supportive information to existing literature. The
standard calibration method of flame atomic absorption spectrophotometry (FAAS) was employed in
the determination of the QHMs. The results indicated presence of the QHMs in the all tissues and fish
species analysed. Their concentrations varied for each metal in the different tissues and species, but
only in few occasions were these variations statistically significant (p < 0.05). T. gallier accumulates the
highest (39%) of Arsenic in the intestine, C. lazera with highest (29%) of Lead in stomach and H.
niloticus showed highest (38%) of Cadmium in the liver. On the whole, the results of this study revealed
that the concentrations of these QHMs are within safe limits for human consumption. The doughnut
plot was found useful for profiling the interactions of the QHMs in fish tissue samples, provide
supportive information to earlier findings and confirms that these metals do show varying
concentrations at different facets of a particular system.