APPLICATION OF PIXE IN THE STUDY OF SHELLFISH

The Bartol in-air Pixe system has been used to study the elemental composition of many varieties of sea life; the sensitivity for the elements from Na to Sr is good, a reasonable spatial resolution is attainable and little preparation of the samples is required. Two examples are cited. First, the composition of the inner nacreous and prismatic regions of mussels (Mytilus edulis) taken monthly (1981-1982) from the Damariscotta River, Maine, has been measured and, second, the shell and soft tissues of oysters (Crassostrea virginica) grown under laboratory conditions on substrate of compacted residues from coal-fired power plants have been analysed. The mussel study shows a rather large anomaly in the Sr/Ca ratio for the nacreous region for May which suggests a possible connection with the reproduction cycle. Oysters grown on metal-containing coal-ash substrata gave tissue and shell metal concentrations similar to natural oysters, an indication of no anomalous uptake of metals from the coal-ash substrata.