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Radiochemical research in Switzerland is pursued in a laboratory jointly financed by Bern University and the Paul Scherrer Institute. Presently, four groups – one at Bern University and three at the Paul Scherrer Institute – perform basic research in heavy element chemistry, atmospheric chemistry, paleoatmospheric studies, and geochemistry. While the first topic resembles frontier research in radiochemistry, the latter three activities involve the use of radiotracers in several environmental research fields. Most of the experiments require access to the accelerator systems and the spallation neutron source at the Paul Scherrer Institute. Some recent results of the four groups are summarized. They include the first ever chemical study of hassium (element 108), the application of the positron emitter 13N for atmospheric studies, the reconstruction of the pollution history over Europe and some radioanalytical studies with meteorites.

The growth rates of ombrotrophic peat bogs are controlled solely by the atmospheric input of nutrients. Such systems serve as archives for the emission of anthropogenic pollutants close to urban centers. Goal of the present investigation was to unravel the history of the deposition of sulfur during the twentieth century. In two peat bogs of the Swiss Midlands peat cores were collected and dated using the lead isotope 210Pb. After a wet digestion of the sample material in pressure bombs by microwave excitation the resulting solutions were measured for their S concentrations by ICP-OES or by IC.The S concentrations vary between 1–5 g/kg of dry sample mass. The comparison with the estimated total sulfur emissions for Switzerland from the BUWAL shows an excellent correlation with two maximal values around the years 1960 and 1980, respectively. The fact that the same deposited amount of pollutant is determined in the two peat bogs situated 50 km apart indicates that the measured signals are not controlled by local sources.

Radiochemical research in Switzerland is pursued in a laboratory jointly financed by Bern University and the Paul Scherrer Institute. Presently, four groups – one at Bern University and three at the Paul Scherrer Institute – perform basic research in heavy element chemistry, atmospheric chemistry, paleoatmospheric studies, and geochemistry. While the first topic resembles frontier research in radiochemistry, the latter three activities involve the use of radiotracers in several environmental research fields. Most of the experiments require access to the accelerator systems and the spallation neutron source at the Paul Scherrer Institute. Some recent results of the four groups are summarized. They include the first ever chemical study of hassium (element 108), the application of the positron emitter 13N for atmospheric studies, the reconstruction of the pollution history over Europe and some radioanalytical studies with meteorites.

The determination of Se became important, since it was recognized that this trace element is essential for the human and animal diet. Lately, it was found that most patients suffering from a cancer disease manifest very low values of Se in their blood plasma. Activation analysis is a well suited technique to measure the concentrations of Se in a vast range of materials with very different concentrations. At the lower end of concentrations, a radiochemical separation of Se following the irradiation is mandatory to obtain reliable results in the determination.

The determination of Se became important, since it was recognized that this trace element is essential for the human and animal diet. Lately, it was found that most patients suffering from a cancer disease manifest very low values of Se in their blood plasma. Activation analysis is a well suited technique to measure the concentrations of Se in a vast range of materials with very different concentrations. At the lower end of concentrations, a radiochemical separation of Se following the irradiation is mandatory to obtain reliable results in the determination.