[en] The need and usefulness of a radiological surveillance program of the marine environment is discussed in relation with radioactive waste dumping, essentially with the aim of establishing a radiological baseline and observe the radioactivity trends. Some results of water, sediments and fish samples collected are presented namely along portuguese coasts, in particular of the scabbard fish (Aphanopus carbo), living at depths about 1800-2200 m, near Madeira island

[en] The spatial and temporal evolution of the ³H levels in the water of the River Tagus in its passage through various regions of Spain and Portugal was analysed. Using mathematical time-series techniques, analytical expressions were obtained for the temporal trend and the periodicity present in the data.These expressions were used to determine the transit times between the sampling sites. The results indicated that the mean speed of ³H displacement was 12 km/month. The residence times of tritium in the water were also obtained. They were found to depend on the sampling points, with values ranging between 31 and 77 months. The concentrations of ³H varied cyclically at the six sampling points, with periods of around 24 months upstream of the Almaraz Nuclear Power Plant and about 12 months downstream

[en] Analysis of survey data on the waters of the Douro and Tejo rivers shows that, for the five year period 1976-1980, fallout ¹³⁷Cs and ⁹⁰Sr were detectable. In sediments and fish, only ¹³⁷Cs, of the same fallout origin, was assayed but the results enable estimation of a ¹³⁷Cs distribution coefficient for sediments of 2 x 10³ and a concentration factor for fish of 10². Towards understanding and interpreting these values further, data for the main stable elements have also been analysed. (author)

[en] The gross beta and tritium activities in the forty Portuguese drinking waters analyzed using the ISO standard methods (Portuguese Guidelines) are below the guidance levels proposed in the Portuguese Drinking Water Quality Guidelines. In what concerns the gross alpha activity only 18% exceeded the recommended level. In general, it can be concluded that the ingestion of these drinking waters does not create a radiological hazard to the human consumption, however, more detailed analyses will be necessary mainly the determinations of the individual alpha emitters radionuclide concentrations. The minimum gross alpha and gross beta detectable activities by L.S.C. methodology are higher than for the proportional counting technique (ISO method). Higher concentration factors will be needed to reach lower required detection limits. (authors)