Radioactivity Exploration from the Arctic to the Antarctic. Part 2. Ymer-80 Expedition

• Main Authors: Persson, Bertil R, Holm, Elis, Carlsson, Kjell-Åke, Samuelsson, Christer, Hallstadius, Lars, Hedvall, Robert, Forkman, Bengt
• Format: Article in Journal/Newspaper
• Language: English
• Published: Bertil RR Persson, Medical Radiation Physics, 22185 Lund, Sweden 2015
• Subjects: Environmental Health and Occupational Health; Ymer-80; air; water; sedimen; biota; 222Rn (radon); 210Pb; 210Po; 137Cs; 239+240Pu; 241Am; Antarctic; Arctic; The Antarctic; Antarc*
• Online Access: https://lup.lub.lu.se/record/8498165; https://doi.org/10.13140/RG.2.1.3542.2164; https://portal.research.lu.se/files/3208394/8498166.pdf

Abstract Levels of natural radioactivity such as 222Rn (radon) and its long-lived daughters 210Pb and 210Po were measured. The radon gas was trapped on cooled charcoal filters and the long-lived daughter products sampled on fibre filters on a daily basis. In addition, short-lived progenies were followed continuously on the filters in order to achieve a time resolution of about one hour. The average 222Rn concentration in air measured during the Ymer-80 expedition in samples north of latitude 78.8 °N, was 33 ± 4 (one standard error) mBq.m-3 during Leg 1 (July-Aug.) , and 105.3 ± 8.3 mBq.m-3 during leg 2 (Aug-Sept.). During a two-week period of persistent polar winds, the mean radon concentration decreased to 19± 5 mBq.m-3. During July, August and September, the monthly average concentrations of 210Pb in air at positions north of 75 °N latitude were 31 ± 15, 89 ± 61 and 105± 57 μBq.m-3 respectively with a the grand average for all 3 months of 75 ± 28 μBq.m-3. An extensive radiochemistry program was also established to measure 134+137Cs and the trans- uranium elements 238+239+240Pu and 241Am in water, sediment and biota. The concentration of 137Cs in surface seawater along the Norwegian coast was quite constant about 157±7 Bq.m-3. At a latitude about 72 oN it stat do decrease exponentially at a rate of 0.43 deg.-1 to about 20 ± 10 Bq.m-3 above 78 oN. The results of 137Cs in sediments indicate that the total integrated area-content of 137Cs in a 1000 m water-column and sediment is about 12 kBq.m-2. In biota, the highest activity concentration of 137Cs about 1000 Bq/kgdwt was found in lichens. The activity concentration of 137Cs in polar bears was about 10 Bq/kgdwt, in seals about 1 Bq/kgdwt, and in birds about 1-7 Bq/kgdwt. The activity-concentration of 137Cs in Fucus and Laminaria was about 1-2 Bq/kgdwt, and the algae/sea-water activity-concentration ratio was about 75. The distribution of the trans-uranium element 239+240Pu in sea water decrease from 14 to 10 mBq.m-3 up to 73°N but increase again to 17 mBq.m-3 at ...