Effects of high stability iron-complexes on the kinetics of iron accumulation and excretion in Mytilus edvlis (L.)

The effects of small molecular weight complexes with a high affinity for iron on the uptake, accumulation and excretion of iron by the common mussel, Mytilus edulis (L.) have been investigated. Fe(III) complexes of citrate, EDTA and 1,10-phenanthroline increased both the rate of uptake and the total amount accumulated when compared to those for particulate ferric hydroxide in sea water, whereas ferrichrome b and the Fe(III) complexes of aceto- and benzo-hydroxamic acids give a decrease. Increased uptake is, however, compensated for by an increased rate of excretion resulting in an almost constant residence time for this metal. The iron is accumulated principally in the viscera with a smaller but significant proportion in the gills. The effects produced by prior complexation of the iron cannot be correlated with either the strength of binding of the complex to the iron or the exchangeability of the iron with other ligands but may be concerned with the endocytosis, the mechanism of uptake for iron previously shown to occur in Mytilus.