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1. Long-term transfer of global fallout 137Cs to cow’s milk in Iceland

Author

Brenda J. Howard, K. Gudnason, S.E. Palsson, and M. A. Sigurgeirsson

Subjects
Soil test, Soil inventory, Significant difference, Environmental engineering, General Medicine, Management, Monitoring, Policy and Law, Pollution, Animal science, Arctic, Deposition density, Environmental science, Spatial variability, Precipitation, Deposition (chemistry), General Environmental Science
Abstract

The aim of this study was to provide improved information on the long-term transfer of global nuclear weapons (137)Cs fallout to cow's milk in Iceland many years after deposition. The spatial variation in deposition was confirmed to be explained by precipitation. Soil samples showed a significant difference in (137)Cs deposition density between the main agricultural areas, with the South having the highest values, then the West and North and the lowest in the Northeast. There was no significant difference between the effective half-lives in (137)Cs activity concentrations in milk and milk powder from the main dairies in Iceland based on data for milk from 1990 to 2007 and for milk powder from 1986 to 2007. There was, however, a significant difference between the effective half-lives obtained for these two regions, 13.5 years for the Northern and 10.5 years for the Southern regions. These half-lives for global fallout are longer than those previously reported for similar time periods in other Arctic areas. The transfer of (137)Cs to cow's milk was quantified for different agricultural regions using aggregated transfer coefficients (T (ag)) for the period of peak global fallout soil inventory in 1965-1967. The values ranged from 2.8 × 10(-3) to 10.6 × 10(-3) m(2) kg(-1). By 2001-2004, the T (ag) values had only declined, in the main agricultural areas, to 0.6 × 10(-3)-1.0 × 10(-3) m(2) kg(-1). Long-term transfer rates to milk many years after deposition were high in Iceland compared with most other reported data. The transfer is potentially relevant for some of the contaminated areas around the Fukushima Nuclear Power Plant after the accident in March 2011 since limited information is available on uptake from Andosols and associated effective half-lives.

Published
2012

2. Radiocaesium fallout behaviour in volcanic soils in Iceland

Author

S.E. Palsson, Olafur Arnalds, M. A. Sigurgeirsson, K. Gudnason, and Brenda J. Howard

Subjects
Radioactive Fallout, Health, Toxicology and Mutagenesis, Iceland, Volcanic Eruptions, Soil Pollutants, Radioactive, Environmental Chemistry, Organic matter, Colloids, Allophane, Waste Management and Disposal, chemistry.chemical_classification, Hydrology, Ice, General Medicine, Pollution, Soil contamination, Andosol, chemistry, Cesium Radioisotopes, Environmental chemistry, Soil water, Histosol, Environmental science, Aeolian processes, Soil horizon, Environmental Monitoring
Abstract

The retention of 137Cs in various types of Andosols in Iceland was investigated. Soils were sampled at 29 sites with varying precipitation and environmental conditions. Samples were obtained from 0 to 5, 5 to 10, and 10 to 15 cm depths. The amount of radiocaesium present was quite variable, ranging between 300 and 4800 Bq m−2 and correlated closely to total annual precipitation (r2 = 0.71). The majority of 137Cs, 82.7% on average, was retained in the uppermost 5 cm of the soil. The greatest penetration of 137Cs was observed for organic Histosols (76.3% in top 5 cm). The Icelandic Vitrisols (barren, poorly developed Andosols) are coarse grained with only 2–5% clay content and contain little organic matter (

Published
2005

3. Tracking of airborne radionuclides from the damaged Fukushima Dai-ichi nuclear reactors by European networks

Author

M. Manolopoulou, J. Bieringer, M. Kettunen, Ó. Halldórsson, Stylianos Stoulos, S. E. Pálsson, Ilia Penev, P.J.M. Kwakman, Philipp Steinmann, Olivier Masson, Fernando P. Carvalho, A. Ugron, Flavia Groppi, Luigi Gini, Simone Manenti, G. Depuydt, B. V. Silobritiene, Jerzy W. Mietelski, K. Isajenko, H. Wershofen, K. Gudnason, E. Vagena, A. Dalheimer, C. Söderström, Clemens Schlosser, Zs. Homoki, M. Reis, N. Tooloutalaie, C. Mc Mahon, Kamil Brudecki, G. Lujaniene, M. Lecomte, Antonio Baeza, K. Holeý, A.-P. Leppänen, Dragana Todorović, B. Lind, Pavel P. Povinec, M. Sonck, Henrik Ramebäck, Sven Poul Nielsen, B. Møller, Thomas Steinkopff, Dieter Hainz, P. Mc Ginnity, P. R. J. Saey, L.-E. De Geer, O. Connan, W. Ringer, Christian Katzlberger, Marija M. Janković, Georg Steinhauser, Damien Didier, Luc Solier, C. Papastefanou, L. León Vintró, Rodolfo Gurriaran, I. Sýkora, D. Hammond, R. Kontro, A. de Vismes, G. Sgorbati, Petr Rulík, Renata Kierepko, M.K. Pham, S. Bucci, Alexander Mauring, Alexandra Ioannidou, Jelena Krneta Nikolić, J. Tschiersch, R. Sogni, V. Samsonov, O. Zhukova, A. Mattila, Alicia Rodríguez, Ronaldus Martinus Wilhelmus Overwater, O. Hanley, Arturo Vargas, Laura Tositti, Helena Malá, M. Cappai, C. Cosma, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Bundesamt für Strahlenschutz (BfS), Henryk Niewodniczanski Institute of Nuclear Physics PAN, Instituto Tecnológico e Nuclear, Instituto Superior Técnico, Universidade Técnica de Lisboa (IST), Laboratoire de Radioécologie de Cherbourg-Octeville (LRC), Babes-Bolyai University [Cluj-Napoca] (UBB), Deutscher Wetterdienst [Offenbach] (DWD), Swedish Defence Research Agency [Stockholm] (FOI), Centre for Radiation, Chemical and Environmental Hazards, Public Health England [London], Department of Nuclear Physics and Biophysics, Comenius University in Bratislava, Aristotle University of Thessaloniki, University College Dublin [Dublin] (UCD), National Radiation Protection Institute (NRPI/SURO), Radiation and Nuclear Safety Authority [Helsinki] (STUK), Institute for Nuclear Research and Nuclear Energy (INRNE), Académie des sciences de Bulgarie, Swiss Federal Office of Public Health, University of Bologna, Universitat Politècnica de Catalunya [Barcelona] (UPC), O. Masson, A. Baeza, J. Bieringer, K. Brudecki, S. Bucci, M. Cappai, F.P. Carvalho, O. Connan, C. Cosma, A. Dalheimer, D. Didier, G. Depuydt, L.E. De Geer, A. De Visme, L. Gini, F. Groppi, K. Gudnason, R. Gurriaran, D. Hainz, Ó. Halldórsson, D. Hammond○, O. Hanley, K. Holeý, Zs. Homoki, A. Ioannidou, K. Isajenko, M. Jankovic, C. Katzlberger, M. Kettunen, R. Kierepko, R. Kontro, P.J.M. Kwakman, M. Lecomte, L. Leon Vintro, A.-P. Leppänen, B. Lind, G. Lujaniene, P. Mc Ginnity, C. Mc Mahon, H. Malá, S. Manenti, M. Manolopoulou, A. Mattila, A. Mauring, J.W. Mietelski, B. Møller, S.P. Nielsen, J. Nikoliκ, R.M.W. Overwater, S. E. Pálsson, Papastefanou, I. Penev, M.K. Pham, P.P. Povinec, H. Ramebäck, M.C. Rei, W. Ringer, A. Rodriguez, P. Rulík, P.R.J. Saey, V. Samsonov, C. Shlosser, G. Sgorbati, B. V. Silobritiene, C. Söderström, R. Sogni, L. Solier, M. Sonk, G. Steinhauser, T. Steinkopff, P. Steinmann, S. Stoulo, I. Sýkora, D. Todorovic, N. Tooloutalaie, L. Tositti, J. Tshiersh, A. Ugron, E. Vagena, A. Varga, H. Wershofen, and and O. Zhukova

Subjects
010504 meteorology & atmospheric sciences, Meteorology, FUKUSHIMA, Induced radioactivity, 010501 environmental sciences, Atmospheric sciences, 7. Clean energy, 01 natural sciences, law.invention, Atmosphere, Iodine Radioisotopes, Washout (aeronautics), RADIOCONTAMINATION, Japan, law, Radiation Monitoring, Nuclear power plant, Environmental Chemistry, 0105 earth and related environmental sciences, Radionuclide, General Chemistry, Particulates, Europe, PLUME, 13. Climate action, Air Pollutants, Radioactive, Cesium Radioisotopes, Nuclear Power Plants, [SDE]Environmental Sciences, ARTIFICIAL RADIOACTIVITY, Environmental science, Radiation monitoring, Contaminated air, Radioactive Hazard Release
Abstract

Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 ( 131I) and cesium isotopes ( 137Cs and 134Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th. Time variations over a 20-day period and spatial variations across more than 150 sampling locations in Europe made it possible to characterize the contaminated air masses. After the Chernobyl accident, only a few measurements of the gaseous 131I fraction were conducted compared to the number of measurements for the particulate fraction. Several studies had already pointed out the importance of the gaseous 131I and the large underestimation of the total 131I airborne activity level, and subsequent calculations of inhalation dose, if neglected. The measurements made across Europe following the releases from the Fukushima NPP reactors have provided a significant amount of new data on the ratio of the gaseous 131I fraction to total 131I, both on a spatial scale and its temporal variation. It can be pointed out that during the Fukushima event, the 134Cs to 137Cs ratio proved to be different from that observed after the Chernobyl accident. The data set provided in this paper is the most comprehensive survey of the main relevant airborne radionuclides from the Fukushima reactors, measured across Europe. A rough estimate of the total 131I inventory that has passed over Europe during this period was \textless1% of the released amount. According to the measurements, airborne activity levels remain of no concern for public health in Europe. © 2011 American Chemical Society.

Published
2011

4. Long-term transfer of global fallout ¹³⁷Cs to cow's milk in Iceland

Author

S E, Pálsson, B J, Howard, K, Gudnason, and M A, Sigurgeirsson

Subjects
Radioactive Fallout, Milk, Cesium Radioisotopes, Radiation Monitoring, Iceland, Animals, Radioactive Hazard Release
Abstract

The aim of this study was to provide improved information on the long-term transfer of global nuclear weapons (137)Cs fallout to cow's milk in Iceland many years after deposition. The spatial variation in deposition was confirmed to be explained by precipitation. Soil samples showed a significant difference in (137)Cs deposition density between the main agricultural areas, with the South having the highest values, then the West and North and the lowest in the Northeast. There was no significant difference between the effective half-lives in (137)Cs activity concentrations in milk and milk powder from the main dairies in Iceland based on data for milk from 1990 to 2007 and for milk powder from 1986 to 2007. There was, however, a significant difference between the effective half-lives obtained for these two regions, 13.5 years for the Northern and 10.5 years for the Southern regions. These half-lives for global fallout are longer than those previously reported for similar time periods in other Arctic areas. The transfer of (137)Cs to cow's milk was quantified for different agricultural regions using aggregated transfer coefficients (T (ag)) for the period of peak global fallout soil inventory in 1965-1967. The values ranged from 2.8 × 10(-3) to 10.6 × 10(-3) m(2) kg(-1). By 2001-2004, the T (ag) values had only declined, in the main agricultural areas, to 0.6 × 10(-3)-1.0 × 10(-3) m(2) kg(-1). Long-term transfer rates to milk many years after deposition were high in Iceland compared with most other reported data. The transfer is potentially relevant for some of the contaminated areas around the Fukushima Nuclear Power Plant after the accident in March 2011 since limited information is available on uptake from Andosols and associated effective half-lives.

Published
2011

5. 2019 ESC Guidelines for the diagnosis and management of chronic coronary syndromes

Author

Knuuti, Juhani, Wijns, William, Saraste, Antti, Capodanno, Davide, Barbato, Emanuele, Funck-Brentano, Christian, Prescott, Eva, Storey, Robert F, Deaton, Christi, Cuisset, Thomas, Agewall, Stefan, Dickstein, Kenneth, Edvardsen, Thor, Escaned, Javier, Gersh, Bernard J, Svitil, Pavel, Gilard, Martine, Hasdai, David, Hatala, Robert, Mahfoud, Felix, Masip, Josep, Muneretto, Claudio, Valgimigli, Marco, Achenbach, Stephan, Bax, Jeroen J, Neumann FJ, Sechtem U, Banning AP, Bonaros N, Bueno H, Bugiardini R, Chieffo A, Crea F, Czerny M, Delgado V, Dendale P, Flachskampf FA, Gohlke H, Grove EL, James S, Katritsis D, Landmesser U, Lettino M, Matter CM, Nathoe H, Niessner A, Patrono C, Petronio AS, Pettersen SE, Piccolo R, Piepoli MF, Popescu BA, Räber L, Richter DJ, Roffi M, Roithinger FX, Shlyakhto E, Sibbing D, Silber S, Simpson IA, Sousa-Uva M, Vardas P, Witkowski A, Zamorano JL, Achenbach S, Agewall S, Barbato E, Bax JJ, Capodanno D, Cuisset T, Deaton C, Dickstein K, Edvardsen T, Escaned J, Funck-Brentano C, Gersh BJ, Gilard M, Hasdai D, Hatala R, Mahfoud F, Masip J, Muneretto C, Prescott E, Saraste A, Storey RF, Svitil P, Valgimigli M, Windecker S, Aboyans V, Baigent C, Collet JP, Dean V, Fitzsimons D, Gale CP, Grobbee D, Halvorsen S, Hindricks G, Iung B, Jüni P, Katus HA, Leclercq C, Lewis BS, Merkely B, Mueller C, Petersen S, Touyz RM, Benkhedda S, Metzler B, Sujayeva V, Cosyns B, Kusljugic Z, Velchev V, Panayi G, Kala P, Haahr-Pedersen SA, Kabil H, Ainla T, Kaukonen T, Cayla G, Pagava Z, Woehrle J, Kanakakis J, Tóth K, Gudnason T, Peace A, Aronson D, Riccio C, Elezi S, Mirrakhimov E, Hansone S, Sarkis A, Babarskiene R, Beissel J, Maempel AJC, Revenco V, de Grooth GJ, Pejkov H, Juliebø V, Lipiec P, Santos J, Chioncel O, Duplyakov D, Bertelli L, Dikic AD, Studenčan M, Bunc M, Alfonso F, Bäck M, Zellweger M, Addad F, Yildirir A, Sirenko Y, Clapp B, Sorbonne Université (SU), Unité de Recherche sur les Maladies Cardiovasculaires, du Métabolisme et de la Nutrition = Institute of cardiometabolism and nutrition (ICAN), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Service de pharmacologie médicale [CHU Pitié-Salpêtrière], CHU Pitié-Salpêtrière [AP-HP], Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Centre recherche en CardioVasculaire et Nutrition = Center for CardioVascular and Nutrition research (C2VN), Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Département de Cardiologie [Hôpital de la Timone - APHM], Hôpital de la Timone [CHU - APHM] (TIMONE)-Assistance Publique - Hôpitaux de Marseille (APHM), Knuuti, Juhani, Wijns, William, Saraste, Antti, Capodanno, Davide, Barbato, Emanuele, Funck-Brentano, Christian, Prescott, Eva, Storey, Robert F, Deaton, Christi, Cuisset, Thoma, Agewall, Stefan, Dickstein, Kenneth, Edvardsen, Thor, Escaned, Javier, Gersh, Bernard J, Svitil, Pavel, Gilard, Martine, Hasdai, David, Hatala, Robert, Mahfoud, Felix, Masip, Josep, Muneretto, Claudio, Valgimigli, Marco, Achenbach, Stephan, Bax, Jeroen J, Neumann FJ, Sechtem U, Banning AP, Bonaros N, Bueno H, Bugiardini R, Chieffo A, Crea F, Czerny M, Delgado V, Dendale P, Flachskampf FA, Gohlke H, Grove EL, James S, Katritsis D, Landmesser U, Lettino M, Matter CM, Nathoe H, Niessner A, Patrono C, Petronio AS, Pettersen SE, Piccolo R, Piepoli MF, Popescu BA, Räber L, Richter DJ, Roffi M, Roithinger FX, Shlyakhto E, Sibbing D, Silber S, Simpson IA, Sousa-Uva M, Vardas P, Witkowski A, Zamorano JL, Achenbach S, Agewall S, Barbato E, Bax JJ, Capodanno D, Cuisset T, Deaton C, Dickstein K, Edvardsen T, Escaned J, Funck-Brentano C, Gersh BJ, Gilard M, Hasdai D, Hatala R, Mahfoud F, Masip J, Muneretto C, Prescott E, Saraste A, Storey RF, Svitil P, Valgimigli M, Windecker S, Aboyans V, Baigent C, Collet JP, Dean V, Delgado V, Fitzsimons D, Gale CP, Grobbee D, Halvorsen S, Hindricks G, Iung B, Jüni P, Katus HA, Landmesser U, Leclercq C, Lettino M, Lewis BS, Merkely B, Mueller C, Petersen S, Petronio AS, Richter DJ, Roffi M, Shlyakhto E, Simpson IA, Sousa-Uva M, Touyz RM, Benkhedda S, Metzler B, Sujayeva V, Cosyns B, Kusljugic Z, Velchev V, Panayi G, Kala P, Haahr-Pedersen SA, Kabil H, Ainla T, Kaukonen T, Cayla G, Pagava Z, Woehrle J, Kanakakis J, Tóth K, Gudnason T, Peace A, Aronson D, Riccio C, Elezi S, Mirrakhimov E, Hansone S, Sarkis A, Babarskiene R, Beissel J, Maempel AJC, Revenco V, de Grooth GJ, Pejkov H, Juliebø V, Lipiec P, Santos J, Chioncel O, Duplyakov D, Bertelli L, Dikic AD, Studenčan M, Bunc M, Alfonso F, Bäck M, Zellweger M, Addad F, Yildirir A, Sirenko Y, Clapp B, Clinical sciences, Cardio-vascular diseases, Cardiology, Knuuti, Juhani [0000-0003-3156-9593], Apollo - University of Cambridge Repository, Unité de Recherche sur les Maladies Cardiovasculaires, du Métabolisme et de la Nutrition = Research Unit on Cardiovascular and Metabolic Diseases (ICAN), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Sorbonne Université (SU)-Institut de Cardiométabolisme et Nutrition = Institute of Cardiometabolism and Nutrition [CHU Pitié Salpêtrière] (IHU ICAN), Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU)-CHU Pitié-Salpêtrière [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Sorbonne Université (SU), Assistance Publique - Hôpitaux de Marseille (APHM)- Hôpital de la Timone [CHU - APHM] (TIMONE), University of Zurich, Knuuti, J., Wijns, W., Achenbach, S., Agewall, S., Barbato, E., Bax, J. J., Capodanno, D., Cuisset, T., Deaton, C., Dickstein, K., Edvardsen, T., Escaned, J., Funck-Brentano, C., Gersh, B. J., Gilard, M., Hasdai, D., Hatala, R., Mahfoud, F., Masip, J., Muneretto, C., Prescott, E., Saraste, A., Storey, R. F., Svitil, P., Valgimigli, M., Windecker, S., Aboyans, V., Baigent, C., Collet, J. -P., Dean, V., Delgado, V., Fitzsimons, D., Gale, C. P., Grobbee, D. E., Halvorsen, S., Hindricks, G., Iung, B., Juni, P., Katus, H. A., Landmesser, U., Leclercq, C., Lettino, M., Lewis, B. S., Merkely, B., Mueller, C., Petersen, S., Petronio, A. S., Richter, D. J., Roffi, M., Shlyakhto, E., Simpson, I. A., Sousa-Uva, M., Touyz, R. M., Benkhedda, S., Metzler, B., Sujayeva, V., Cosyns, B., Kusljugic, Z., Velchev, V., Panayi, G., Kala, P., Haahr-Pedersen, S. A., Kabil, H., Ainla, T., Kaukonen, T., Cayla, G., Pagava, Z., Woehrle, J., Kanakakis, J., Toth, K., Gudnason, T., Peace, A., Aronson, D., Riccio, C., Elezi, S., Mirrakhimov, E., Hansone, S., Sarkis, A., Babarskiene, R., Beissel, J., Cassar Maempel, A. J., Revenco, V., de Grooth, G. J., Pejkov, H., Juliebo, V., Lipiec, P., Santos, J., Chioncel, O., Duplyakov, D., Bertelli, L., Dikic, A. D., Studencan, M., Bunc, M., Alfonso, F., Back, M., Zellweger, M., Addad, F., Yildirir, A., Sirenko, Y., and Clapp, B.

Subjects
anti-ischaemic drug, chronic coronary syndromes, medicine.medical_treatment, [SDV]Life Sciences [q-bio], lipid-lowering drugs, Diagnostic Techniques, Cardiovascular, antithrombotic therapy, Disease, 030204 cardiovascular system & hematology, Guideline, Coronary artery disease, 0302 clinical medicine, Disease management (health), Societies, Medical, ComputingMilieux_MISCELLANEOUS, chronic coronary syndrome, angina pectori, Disease Management, food and beverages, imaging, risk assessment, Syndrome, 3. Good health, Natural history, Europe, Cardiology, Cardiology and Cardiovascular Medicine, coronary artery disease, medicine.medical_specialty, lifestyle modifications, anti-ischaemic drugs, Ischemia, 610 Medicine & health, vasospastic angina, Guidelines, Revascularization, diagnostic testing, 11171 Cardiocentro Ticino, 2705 Cardiology and Cardiovascular Medicine, 03 medical and health sciences, angina pectoris, [SDV.MHEP.CSC]Life Sciences [q-bio]/Human health and pathology/Cardiology and cardiovascular system, Internal medicine, medicine, Journal Article, Humans, business.industry, screening, fungi, 030229 sport sciences, medicine.disease, lipid-lowering drug, Angina pectoris, Anti-ischaemic drugs, Antithrombotic therapy, Chronic coronary syndromes, Diagnostic testing, Imaging, Lifestyle modifications, Lipid-lowering drugs, Microvascular angina, Myocardial ischaemia, Myocardial revascularization, Risk assessment, Screening, Vasospastic angina, myocardial ischaemia, myocardial revascularization, Heart failure, microvascular angina, Chronic Disease, Settore MED/11 - MALATTIE DELL'APPARATO CARDIOVASCOLARE, lifestyle modification, Coronary Artery Disease/diagnosis, business, Fibrinolytic agent
Abstract

Coronary artery disease (CAD) is a pathological process characterized by atherosclerotic plaque accumulation in the epicardial arteries, whether obstructive or non-obstructive. This process can be modified by lifestyle adjustments, pharmacological therapies, and invasive interventions designed to achieve disease stabilization or regression. The disease can have long, stable periods but can also become unstable at any time, typically due to an acute atherothrombotic event caused by plaque rupture or erosion. However, the disease is chronic, most often progressive, and hence serious, even in clinically apparently silent periods. The dynamic nature of the CAD process results in various clinical presentations, which can be conveniently categorized as either acute coronary syndromes (ACS) or chronic coronary syndromes (CCS). The Guidelines presented here refer to the management of patients with CCS. The natural history of CCS is illustrated in Figure 1.

Published
2019

6. Evaluation of 137 Cs, 133 Xe and 3 H activity concentrations monitored in the Arctic atmosphere.

Author

Zhang W, Paatero J, Leppänen AP, Møller B, Jensen LK, Gudnason K, Sofiev M, Anderson P, Sickel M, Burakowska A, Kubicki M, and Anderson A

Subjects
Arctic Regions, Atmosphere, Cesium Radioisotopes analysis, Gases, Soil, Air Pollutants, Radioactive analysis, Radiation Monitoring methods
Abstract

This paper provides a brief introduction to the Arctic atmospheric radioactivity monitoring network. A decade of monitoring results have shown the 137 Cs background levels in Arctic air range from 0.05 to 1.50 μBq/m 3 . The monitoring stations have sufficient sensitivity to detect 137 Cs brought to the atmosphere due to resuspension in local soil and reemissions from biomass burning in a daily temporal resolution. These observations can be used as tracers for atmospheric processes. The 133 Xe measurements obtained at Yellowknife, Resolute and Spitsbergen could support other research into how air pollution problems arise across intercontinental distances. It will help develop and improve models capable of predicting the long-distance transport and deposition of trace gases in the Arctic. Rainwater monitoring data collected in Finnish Lapland since the 1960's indicate that 3 H radioactivity concentrations reached natural background levels in early 2000s, typically around 1-2 Bq/L monthly, with an annual seasonal variation cycle consistent with the observed of other cosmogenic radionuclides., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: This paper is based on work conducted as part of AMAP’s radioactivity assessment work. The information in this paper is part of the scientific basis for the 2023 AMAP Radioactivity Assessment, (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Published
2022
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7. Multi-region finite element modelling of drug release from hydrogel based ophthalmic lenses.

Author

Gudnason K, Sigurdsson S, and Jonsdottir F

Subjects
Adsorption, Computer Simulation, Contact Lenses, Hydrophilic, Diffusion, Finite Element Analysis, Humans, Hydrogels chemistry, In Vitro Techniques, Linear Models, Mathematical Concepts, Administration, Ophthalmic, Drug Delivery Systems, Drug Liberation physiology, Lenses, Intraocular, Models, Biological
Abstract

Understanding the way in which drug is released from drug carrying hydrogel based ophthalmic lenses aids in the development of efficient ophthalmic drug delivery. Various solute-polymer interactions affect solute diffusion within hydrogels as well as hydrogel-bulk partitioning. Additionally, surface modifications or coatings may add to resistance of mass transfer across the hydrogel interface. It is necessary to consider both interfacial resistances as well as the appropriate driving force when characterizing interface flux. Such a driving force is induced by a difference in concentration which deviates from equilibrium conditions. We present a Galerkin finite element approach for solute transport in hydrogels which accounts for diffusion within the gel, storage effects due to polymer-solute interaction, as well as partitioning and mass transfer resistance effects at the interface. The approach is formulated using a rotational symmetric model to account for realistic geometry. We show that although the resulting global system is not symmetric in the case of partitioning, it is similar to a symmetric negative semidefinite system. Thus, it has non-positive real eigenvalues and is coercive, ensuring the validity of the finite element formulation as well as the numerical stability of the implicit backward Euler time integration method employed. Two models demonstrating this approach are presented and verified with release experimental data. The first is the release of moxifloxacin from intraocular lenses (IOLs) plasma grafted with different polyacrylates. The second accounts for both loading as well as the release of diclofenac from disc shaped IOL material loaded for varied time periods and temperature., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Published
2021
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8. A numerical framework for drug transport in a multi-layer system with discontinuous interlayer condition.

Author

Gudnason K, Sigurdsson S, Snorradottir BS, Masson M, and Jonsdottir F

Subjects
Computer Simulation, Finite Element Analysis, Humans, Lenses, Intraocular, Mathematical Concepts, Skin Absorption, Drug Delivery Systems statistics & numerical data, Models, Biological, Pharmacokinetics
Abstract

Discontinuous boundary conditions arise naturally when describing various physical phenomena and numerically modelling such conditions can prove difficult. In the field of pharmaceutical sciences, two such cases are the partitioning of a compound between different materials and a flux rate membrane controlling mass transfer between materials which both result in a discontinuous jump in concentration across adjacent materials. In this study, we introduce a general one-dimensional finite element drug delivery framework, which along with diffusion, reversible binding and dissolution within material layers, incorporates the partitioning and mass transfer conditions between layers of material. We apply the framework to construct models of experiments, which along with experimental data, allow us to infer pharmacokinetic properties of potential material for drug delivery. Understanding such material properties is the key to optimising the therepeutic effect of a targeted drug delivery system., (Copyright © 2017. Published by Elsevier Inc.)

Published
2018
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9. Long-term transfer of global fallout ¹³⁷Cs to cow's milk in Iceland.

Author

Pálsson SE, Howard BJ, Gudnason K, and Sigurgeirsson MA

Subjects
Animals, Iceland, Radioactive Hazard Release, Cesium Radioisotopes analysis, Milk chemistry, Radiation Monitoring, Radioactive Fallout analysis
Abstract

The aim of this study was to provide improved information on the long-term transfer of global nuclear weapons (137)Cs fallout to cow's milk in Iceland many years after deposition. The spatial variation in deposition was confirmed to be explained by precipitation. Soil samples showed a significant difference in (137)Cs deposition density between the main agricultural areas, with the South having the highest values, then the West and North and the lowest in the Northeast. There was no significant difference between the effective half-lives in (137)Cs activity concentrations in milk and milk powder from the main dairies in Iceland based on data for milk from 1990 to 2007 and for milk powder from 1986 to 2007. There was, however, a significant difference between the effective half-lives obtained for these two regions, 13.5 years for the Northern and 10.5 years for the Southern regions. These half-lives for global fallout are longer than those previously reported for similar time periods in other Arctic areas. The transfer of (137)Cs to cow's milk was quantified for different agricultural regions using aggregated transfer coefficients (T (ag)) for the period of peak global fallout soil inventory in 1965-1967. The values ranged from 2.8 × 10(-3) to 10.6 × 10(-3) m(2) kg(-1). By 2001-2004, the T (ag) values had only declined, in the main agricultural areas, to 0.6 × 10(-3)-1.0 × 10(-3) m(2) kg(-1). Long-term transfer rates to milk many years after deposition were high in Iceland compared with most other reported data. The transfer is potentially relevant for some of the contaminated areas around the Fukushima Nuclear Power Plant after the accident in March 2011 since limited information is available on uptake from Andosols and associated effective half-lives.

Published
2012
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10. Tracking of airborne radionuclides from the damaged Fukushima Dai-ichi nuclear reactors by European networks.

Author

Masson O, Baeza A, Bieringer J, Brudecki K, Bucci S, Cappai M, Carvalho FP, Connan O, Cosma C, Dalheimer A, Didier D, Depuydt G, De Geer LE, De Vismes A, Gini L, Groppi F, Gudnason K, Gurriaran R, Hainz D, Halldórsson Ó, Hammond D, Hanley O, Holeý K, Homoki Z, Ioannidou A, Isajenko K, Jankovic M, Katzlberger C, Kettunen M, Kierepko R, Kontro R, Kwakman PJ, Lecomte M, Leon Vintro L, Leppänen AP, Lind B, Lujaniene G, Mc Ginnity P, Mc Mahon C, Malá H, Manenti S, Manolopoulou M, Mattila A, Mauring A, Mietelski JW, Møller B, Nielsen SP, Nikolic J, Overwater RM, Pálsson SE, Papastefanou C, Penev I, Pham MK, Povinec PP, Ramebäck H, Reis MC, Ringer W, Rodriguez A, Rulík P, Saey PR, Samsonov V, Schlosser C, Sgorbati G, Silobritiene BV, Söderström C, Sogni R, Solier L, Sonck M, Steinhauser G, Steinkopff T, Steinmann P, Stoulos S, Sýkora I, Todorovic D, Tooloutalaie N, Tositti L, Tschiersch J, Ugron A, Vagena E, Vargas A, Wershofen H, and Zhukova O

Subjects
Europe, Japan, Nuclear Power Plants, Radiation Monitoring, Air Pollutants, Radioactive analysis, Cesium Radioisotopes analysis, Iodine Radioisotopes analysis, Radioactive Hazard Release
Abstract

Radioactive emissions into the atmosphere from the damaged reactors of the Fukushima Dai-ichi nuclear power plant (NPP) started on March 12th, 2011. Among the various radionuclides released, iodine-131 ((131)I) and cesium isotopes ((137)Cs and (134)Cs) were transported across the Pacific toward the North American continent and reached Europe despite dispersion and washout along the route of the contaminated air masses. In Europe, the first signs of the releases were detected 7 days later while the first peak of activity level was observed between March 28th and March 30th. Time variations over a 20-day period and spatial variations across more than 150 sampling locations in Europe made it possible to characterize the contaminated air masses. After the Chernobyl accident, only a few measurements of the gaseous (131)I fraction were conducted compared to the number of measurements for the particulate fraction. Several studies had already pointed out the importance of the gaseous (131)I and the large underestimation of the total (131)I airborne activity level, and subsequent calculations of inhalation dose, if neglected. The measurements made across Europe following the releases from the Fukushima NPP reactors have provided a significant amount of new data on the ratio of the gaseous (131)I fraction to total (131)I, both on a spatial scale and its temporal variation. It can be pointed out that during the Fukushima event, the (134)Cs to (137)Cs ratio proved to be different from that observed after the Chernobyl accident. The data set provided in this paper is the most comprehensive survey of the main relevant airborne radionuclides from the Fukushima reactors, measured across Europe. A rough estimate of the total (131)I inventory that has passed over Europe during this period was <1% of the released amount. According to the measurements, airborne activity levels remain of no concern for public health in Europe.

Published
2011
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11. Radiocaesium fallout behaviour in volcanic soils in Iceland.

Author

Sigurgeirsson MA, Arnalds O, Palsson SE, Howard BJ, and Gudnason K

Subjects
Cesium Radioisotopes analysis, Colloids, Environmental Monitoring, Ice, Iceland, Radioactive Fallout analysis, Soil Pollutants, Radioactive analysis, Volcanic Eruptions
Abstract

The retention of 137Cs in various types of Andosols in Iceland was investigated. Soils were sampled at 29 sites with varying precipitation and environmental conditions. Samples were obtained from 0 to 5, 5 to 10, and 10 to 15 cm depths. The amount of radiocaesium present was quite variable, ranging between 300 and 4800 Bq m(-2) and correlated closely to total annual precipitation (r2=0.71). The majority of 137Cs, 82.7% on average, was retained in the uppermost 5 cm of the soil. The greatest penetration of 137Cs was observed for organic Histosols (76.3% in top 5 cm). The Icelandic Vitrisols (barren, poorly developed Andosols) are coarse grained with only 2-5% clay content and contain little organic matter (<1%). Yet these soils retained 74% of 137Cs in the top 5 cm. The results indicate that radiocaesium fallout is strongly retained by colloidal materials characteristic of Andosols, such as allophane and ferrihydrite. Most soils in Iceland are subject to severe and prolonged freezing and waterlogging; despite this, 137Cs is retained in the upper soil horizons and vertical migration is negligible in Icelandic Andosols. However, erosion and aeolian activity can markedly influence the amount and vertical distribution of radiocaesium in Icelandic soils.

Published
2005
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