Reference material for radionuclides in sediment IAEA-384 (Fangataufa Lagoon sediment)

Author Posting. © Springer, 2007. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Journal of Radioanalytical and Nuclear Chemistry 273 (2007): 383-393, doi:10.1007/s10967-007-6898-4.A reference material designed for the determination of anthropogenic and natural radionuclides in sediment, IAEA-384 (Fangataufa Lagoon sediment), is described and the results of certification are presented. The material has been certified for 8 radionuclides (40K, 60Co, 155Eu, 230Th, 238U, 238Pu, 239+240Pu and 241Am). Information values are given for 12 radionuclides (90Sr, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 232Th, 234U, 235U, 239Pu, 240Pu and 241Pu). Less reported radionuclides include 228Th, 236U, 239Np and 242Pu. The reference material may be used for quality management of radioanalytical laboratories engaged in the analysis of radionuclides in the environment, as well as for the development and validation of analytical methods and for training purposes. The material is available from IAEA in 100 g units

Reference Material for Radionuclides in Sediment, IAEA-384 (Fangataufa Lagoon Sediment)

The IAEA Marine Environment Laboratory (IAEA-MEL) in Monaco has conducted intercomparison exercises on radionuclides in marine samples for many years as part of its contribution to the IAEA's program of Analytical Quality Control Services (AQCS). An important part of the AQCS program has been a production of Reference Materials (RMs) and their provision to radioanalytical laboratories. The RMs have been developed for different marine matrices (sediment, water, biota), with accuracy and precision required for the present state of the art of radiometrics and mass spectrometry methods. The RMs have been produced as the final products of world-wide intercomparison exercises organized during last 30 years. A total of 44 intercomparison exercises were undertaken and 39 RMs were produced for radionuclides in the marine environment. All required matrices (seawater, biota, sediment) have been covered with radionuclide concentrations ranging from typical environmental levels to elevated levels affected by discharges from nuclear reprocessing plants. The long-term availability of RMs (over 10 years) requires the use of very specific techniques to collect and pretreat large quantities of material (e.g., in excess of 100 kg) in order to ensure sample stability and homogenization of any analytes of interest. The production of a RM is therefore a long process, covering the identification of needs, sample collection, pre-treatment, homogenization, bottling, distribution to laboratories, evaluation of data, preliminary reporting, additional analyses in expert laboratories, certification of the material, and finally issuing the RM. In this paper we describe a reference material IAEA-384, Fangataufa lagoon sediment, designed for determination of anthropogenic and natural radionuclides in the marine environment. This RM has been prepared with the aim of testing the performance of analytical laboratories to measure the activity of these radionuclides in a sediment sample contaminated by elevated levels of fallout from nuclear weapons tests. Participating laboratories were requested to determine as many radionuclides as possible by radiometric (alpha, beta and gamma-spectrometry) as well as by mass spectrometry methods (e.g., ICPMS - Inductively Coupled Plasma Mass Spectrometry, TIMS - Thermal Ionization Mass Spectrometry, AMS - Accelerator Mass Spectrometry)

Transuranic and fission product determination in soils and sediments from Alpin Wetland, Boréon (France)

The study of an Alpine Wetland presented in this study can bring interesting answers to the problems of the environment management. The determination of the radionuclides in soils and sediments has allowed not only to establish the history of depositions and consequently the origin of the radionuclides, but also to evaluate the various transfers, which took place. The studied elements are plutonium 238, 239-240, americium 241, caesium 134, 137 and strontium 90. The detailed vertical study of sediment core shows the accumulation mode and gives information on the sedimentation rate of the small lake. The study of isotopic ratios allows understanding the origin and the environmental behaviour of the elements. Soil core inventory shows the activity on this region. The evolution of the activity versus the altitude is made

Etude de la radioactivité anthropique résiduelle dans un petit bassin-versant des Alpes.

National audienceEtude de la radioactivité anthropique résiduelle dans un petit bassin-versant des Alpes

Structural changes in caudate nucleus, cerebral cortex and hippocampus induced by morphine. Light microscopy study

Lake Chapala, located 120 km northeast of Colima Volcano, lies at the north and northeast of the Citala rift in the Trans-Mexican Volcanic Belt. It belongs to the watershed of the Lerma River, which originates from the Mexico City area, 450 km to the east. Sediment cores, 0.5-2 m long, were collected from the lake. Magnetic susceptibility of the lake sediments generally ranges from 400 to 800 10-9 m3 kg-1; but in some layers it exceeds 1000 or 1500 10-9 m3 kg-1. The magnetic susceptibility vertical profiles display a thin peak (2-5 cm) or a double peak with magnetic susceptibility > 2000 10-9 m3 kg-1. Scanning electron microscope analysis shows that the main mineral responsible for the magnetic susceptibility is titano-magnetite, which is relatively abundant in the magnetic layers. In most of the cores, the layer with magnetic susceptibility > 2000 10 -9 m3 kg-1 is coarser grained than the directly under and overlying sediments, which are composed of fine silt. But not all coarser levels are magnetic nor are all magnetic levels bound to coarser layers. The high titano-magnetic concentration probably originates from volcanic ash falls. Sedimentation rates, evaluated for several sites by means of the 210Pb and 137Cs methods, allow a date approximation (between 1535 and 1670) for the strong magnetic layer deposition. Since important eruptions of Colima Volcano, with ash fall, were reported from 1576 to 1623, the main peak of magnetic susceptibility in the sediment profiles is assumed to be related to these events. The main magnetic layer extends to greater depth in the profiles of the eastern part of the lake plain than at the west. It can, therefore, be suggested that a relative subsidence occurs in the eastern part of the lake; the axis of the eastern plain overlaps the area displaying the maximum subsidence rate and seems therefore to correspond to the prolongation of Citala rift. " Springer 2006.",,,,,,"10.1007/s10933-005-5971-7",,,"http://hdl.handle.net/20.500.12104/44776","http://www.scopus.com/inward/record.url?eid=2-s2.0-33745586758&partnerID=40&md5=9f5b53cc6e0b450a2b04bec9b21bdf09",,,,,,"4",,"Journal of Paleolimnology",,"81

Strong magnetic levels in Lake Chapala sediments (western Mexico) : their mineralogy and stratigraphic significance

Lake Chapala, located 120 km northeast of Colima Volcano, lies at the north and northeast of the Citala rift in the Trans-Mexican Volcanic Belt. It belongs to the watershed of the Lerma River, which originates from the Mexico City area, 450 km to the east. Sediment cores, 0.5-2 m long, were collected from the lake. Magnetic susceptibility of the lake sediments generally ranges from 400 to 800 x 10(-9) m(3) kg(-1); but in some layers it exceeds 1000 or 1500 x 10(-9) m(3) kg(-1). The magnetic susceptibility vertical profiles display a thin peak (2-5 cm) or a double peak with magnetic susceptibility > 2000 x 10(-9) m(3) kg(-1). Scanning electron microscope analysis shows that the main mineral responsible for the magnetic susceptibility is titano-magnetite, which is relatively abundant in the magnetic layers. In most of the cores, the layer with magnetic susceptibility > 2000 x 10(-9) m(3) kg(-1) is coarser grained than the directly under and overlying sediments, which are composed of fine silt. But not all coarser levels are magnetic nor are all magnetic levels bound to coarser layers. The high titano-magnetic concentration probably originates from volcanic ash falls. Sedimentation rates, evaluated for several sites by means of the Pb-210 and Cs-137 methods, allow a date approximation (between 1535 and 1670) for the strong magnetic layer deposition. Since important eruptions of Colima Volcano, with ash fall, were reported from 1576 to 1623, the main peak of magnetic susceptibility in the sediment profiles is assumed to be related to these events. The main magnetic layer extends to greater depth in the profiles of the eastern part of the lake plain than at the west. It can, therefore, be suggested that a relative subsidence occurs in the eastern part of the lake; the axis of the eastern plain overlaps the area displaying the maximum subsidence rate and seems therefore to correspond to the prolongation of Citala rift