A method is described incorporating the procedures used in the radiochemical assay of Pu, Am and radiostrontium in environmental samples into a single radioanalytical sequential scheme. Sequential schemes have been used for determining the transuranic nuclides (isotopes of Pu and Am) in various types of sample matrices, but do not normally incorporate90Sr within the same scheme. The method offers potential savings in analyst time and reagents for the analyses of these nuclides, and is particularly suitable for small analytical laboratories where manpower resources coupled with a limited working time (8-hour working day) are constraints, and where limited amounts of sample are submitted for the analyses of all 3 radionuclides.
We have experience of two methods for the analysis of 14C in environmental samples and have used this experience to directly compare these two techniques. Nine vegetation samples and a sucrose standard were analyzed using the benzene synthesis and combustion techniques. The results obtained using both methods were in good agreement and show that 14C data obtained using either technique are comparable. The analytical requirements for the two techniques vary considerably. In choosing a technique, a variety of factors such as sensitivity, sample size, sample type, carbon content and how the results are to be expressed, need to be considered.
Authors:A. Sanchez, D. Singleton, B. Walters, and J. Cobb
The British Nuclear Fuels Limited (BNFL) complex (Sellafield) in Cumbria discharges into the atmosphere, under authorization by the Environment Agency (and previously, the Ministry of Agriculture, Fisheries and Food (MAFF), radioactive waste consisting of gases, mists and dusts. As part of MAFF's radiological surveillance programme, the intake of radionuclides via food ingestion by members of the public living near this nuclear installation is routinely assessed from measurements made on local food and environmental samples and by using computer models simulating the dispersion and incorporation of radioactivity into foodstuffs. In this study, the individual diets of adults and children living near the Sellafield complex and those from a control group were assessed for their radionuclide content. The participants were selected via a food survey questionnaire which was aimed at identifying those who consume home grown fruits and vegetables or derive these from local sources. The diets were collected over a one-week period in August 1995 and following radiochemical analyses of the diets for239+240Pu,137Cs,90Sr,14C, and129I, the doses received by the participants from these nuclides were extrapolated over a one-year period and compared to doses calculated from food surveillance data and to doses predicted using the MAFF food-chain computer model.