Distribution of trace metals in a ling (Genypterus blacodes) fish fillet

The distribution of trace metals in a ling (Genypterus blacodes) fish fillet was determined from ICP-MS measurements of digests prepared using nitric acid and hydrogen peroxide, followed by microwave digestion. Most trace elements were inhomogeneously distributed in the muscle tissue of the ling with a non-linear increase in concentration towards the tail end of the fillet. This distribution pattern may be connected to the size variation of the individual muscle cells or the change in the ratio of connective tissue to muscle tissue, suggesting that the observed inhomogeneity of muscle elemental distribution may be inherent to all fish species. The concentration of an element in a sample of fish muscle tissue thus depends on the physical location within the fish from which the sample was dissected. Significant differences in trace element concentrations were also detected between the red and white muscle fibres of ling, as well as between the belly flap and the rest of the musculature.