Sm. Adams et al., AN ULTRASTRUCTURAL AND MICROANALYTICAL STUDY OF METAL-ION CONTENT IN GRANULAR CONCRETIONS OF THE FRESH-WATER MUSSEL HYRIDELLA-DEPRESSA, Micron, 28(1), 1997, pp. 1-11
Intracellular and extracellular granules in the gonad and mantle of th
e Australian freshwater mussel Hyridella depressa were examined and an
alysed using SERI, TEM and STEM techniques. As is characteristic of fr
eshwater mussels, this species has extensive aggregations of granular
concretions in the extracellular matrix. Energy Dispersive Spectroscop
y (EDS) was used to characterise the metal-ion content of these granul
es and three X-ray microanalytical techniques were investigated to det
ermine the most efficient method of analysis. The granule types were f
ound to differ in their metal-ion composition and concentration, size
and degree of annulation with the most abundant granule type having a
high calcium phosphate content. Secondary Ion Mass Spectroscopy (SIMS)
was also investigated as a comparative technique to characterise the
metal-ion profile of these granules, but was found to have limitations
in imaging and resolution. The potential for using granular concretio
ns in H. Depressa as a method for detecting aquatic toxicants was esta
blished. (C) 1997 Elsevier Science Ltd.