Levels of ²¹⁰Po and ²¹⁰Pb in fish and molluscs in Slovenia and the related dose assessment to the population

²¹⁰Po and ²¹⁰Pb activity concentrations in fish from the Slovenian part of Adriatic Sea, in the vicinity of a former uranium mine at ?irovski vrh and from the Slovenian market were determined. In addition, ²¹⁰Po and ²¹⁰Pb activity concentrations in squid from the Slovenian market and in mussels from the Slovenian part of the Adriatic Sea were also determined. Fish, squid and mussel consumption in Slovenia was assessed from the data available from Eurostat and Food and Agriculture Organisation (FAO) and the data used for the corresponding dose calculation. Fish species with the highest activity concentrations were grilled to assess possible loss of ²¹⁰Po during the food preparation process. Samples were freeze dried and radiochemical separation of ²¹⁰Po and ²¹⁰Pb was performed. Measurements of ²¹⁰Po were performed by alpha spectrometry and ²¹⁰Pb by a low background gas-flow proportional counter. ²¹⁰Po activity concentrations in fish, squid and mussels were from 0.039 to 35.0 Bq kg⁻¹ fresh weight and ²¹⁰Pb activity concentrations were from 0.08 to 3.03 Bq kg⁻¹ fresh weight. Grilling of fish resulted in no significant loss of ²¹⁰Po at 90 °C. The assessed combined annual effective ingestion dose due to ²¹⁰Po and ²¹⁰Pb for fish, squid and mussels consumed in Slovenia is 47.6 μSv year⁻¹.     

GIS and aquaculture: Assessment of soft-shell clam sites

The 1992 collapse of the northern cod fishery at Newfoundland, Canada and the subsequent closure of a majority of the inshore ground fishery has placed a focus on the development of aquaculture within the province. In May 1995 Innovative Fisheries Inc. of St. John's, Newfoundland, conducted field studies to evaluate the soft-shell clam (edible bivalve molluscs) resources on three sand flats near Burgeo, Newfoundland. GIS can be used to examine issues regarding the development and management of the soft-shell clam beds. GIS can also be applied to examine the issue of ‘competing uses’ for the proposed soft-shell clam aquaculture site. The information presented in this study indicates that GIS is an important tool for the aquaculture industry. These systems can be used to monitor, quantify and evaluate the soft-shell beds near Burgeo. Management issues such as water quality, resource sustainability as well as the economic viability of the clam resource can be assessed within a GIS environment. The results of the analysis in this study suggest potential problems with faecal coliform contamination from local cottages. Finally, data collection for aquaculture site assessment is required if a resource is to be managed effectively. GIS applications provide insights into the quality of the physical environment as well as the sustainability of a resource. However, it is the aquaculture operators who ultimately make the final decisions.     

Bioaccumulation of platinum group metals on some fish species ( Oreochromis niloticus,Penaeus laspisulcates,Scylla serrate,Galaxias brevipinnis and Mollusc ) in the Pra estuary of Ghana

Catalytic converters have been designed to solve the problem of pollution from automobiles. However, recent studies have shown that the platinum group metals (PGMs) that are used in the design are being deposited alongside highways. The objective of this study was to measure the levels of PGMs that bioaccumulate in Oreochromis niloticus, Penaeus laspisulcates, Scylla serrate, Galaxias brevipinnis and Mollusc in the river Pra estuary along a major highway in Ghana. Chemical analysis using neutron activation analysis showed accumulation of the PGMs in all the biota species analysed. The S. serrate and mollusc showed higher accumulation than the other species. The mollusc and the other fish species in the estuary are consumed in Ghana, and therefore there is the need to educate the population on the effect of the PGMs on their health.