Radionuclides, environmental

Sutton WW, Patzer RG, Potter GD. 1979. Biotransport of transuranium radionuclides. Environmental Monitoring Systems Laboratory, U.S. Environmental Protection Agency, Las Vegas, NV. NHS No. EMSLLV05 3 93 5. 

The SEAM model has put together established models of atmospheric dispersion and deposition, terrestrial foodchains, marine dispersion and concentration in marine biota and the sea-to-land transfer of radionuclides. Environmental measurements from a wide variety of sources have been compared against values calculated from the discharge chronology and the SEAM model in order both to validate the model and to build confidence in the discharge chronology. 

WHO. 1983. Selected radionuclides. Environmental Health Criteria 25. Geneva World Health Organization. 

People living in areas contaminated with natural or human made long lived radionuclides are usually subjected to exposure via multiple pathways. The contributions of external doses and internal (i.e. by ingestion and inhalation) doses depend on the isotopic compositions and the physical and chemical forms of the radionuclides, environmental conditions and the habits of the population. 

Dr Jessica Avivar Cerezo bom in Palma de Mallorca (Spain), and graduated from the University of the Balearic Islands (Spain) in chemistry, where she also developed her PhD in chemical science and technology. She is the coauthor of a book chapter related to environmental monitoring. Dr Avivar has published approximately 20 research articles and has presented more than 20 contributions at international conferences related with the environment, automation, and radioactivity. Researcher at the University of the Balearic Islands, secretary of the Laboratory of Environmental Radioactivity (LaboRA) and member of the university spin-off Sciware Systems, S.L. Her research has been mainly focused in the development of automated approaches for radionuclides environmental monitoring. 

For a radionuclide to be an effective oceanic tracer, various criteria that link the tracer to a specihc process or element must be met. Foremost, the environmental behavior of the tracer must closely match that of the target constituent. Particle affinity, or the scavenging capability of a radionuclide to an organic or inorganic surface site i.e. distribution coefficient, Kf, is one such vital characteristic. The half-life of a tracer is another characteristic that must also coincide well with the timescale of interest. This section provides a brief review of the role of various surface sites in relation to chemical scavenging and tracer applications. 

Environmental Migration of Long-lived Radionuclides" International Atomic Energy Agency Vienna, 1982. 

Wahlgren, M.A. and Orlandini, K.A., "Environmental Migration of Long-Lived Radionuclides" STI/PUB/597, International Atomic-Energy Agency, 1982, pp. 757-774. 

The nuclear power plant accident at Chernobyl in April 1986 (IAEA Technical Report 1991) proved to be a much more potent source of environmental contamination in many surrounding countries, over distances up to several thousands of kilometers, and was a cause of worldwide problems in international trade in food products contaminated (or possibly contaminated) with radionuclides. The resulting requirement by many countries to establish systems for monitoring radionuclides in foodstuffs and in the environment led to a large worldwide increase in the demand for suitable reference materials. 

Total Elements There is a dearth of elemental concentration data for a wide range of nutritionally, toxicologically, clinically, and environmentally pertinent elements. Some of the elements for which total concentration information is still required, usually at the low end of concentration range but occasionally at the high end, are Al, Ba, B, Be, Br, Cs, F, I, Li, Mo, N, Pt, S, Sb, Si, Sn, Th, Ti, TI, U, V, W, rare earth elements, and radionuclides. Thus, it would seem advisable to certify each new RM for as many elements as possible so that certified values would be available for a larger number of elements in addition to the small number of core elements typical of many current RMs. 

Cochran JK, Bacon MP, Krishnaswami S, Turekian KK (1983) °Po and °Pb distributions in the central and eastern Indian Ocean. Earth Planet Sci Lett 65 433-445 Cochran JK, Livingston HD, Hirschberg DJ, Surprenant LD (1987) Natural and anthropogenic radionuclide distributions in the northwest Atlantic-ocean. Earth Planet Sci Lett 84 135-152 Cochran JK (1992) The oceanic chemistiy of the uranium and thorium-series nuclides In Uranium-series disequihbrium applications to earth, marine, and environmental sciences. Ivanovich M, Harmon RS (eds) Oxford University Press, New York, p 334-395... 

Heussner S, Cherry RD, Heyraud M (1990) Po-210 and Pb-210 in sediment trap particles on a Mediterranean continental margin. Cont. Shelf Res 10 989-100 Heyraud M, Cherry RD (1983) Correlation of Po-210 and Pb-210 enrichments in the sea-surface microlayer with neuston biomass. Cont Shelf Res 1 283-293 Honeyman BD, Santschi PH (1989)The role of particles and colloids in the transport of radionuclides and trace metals in the oceans. In Environmental particles. Buffle J, van Leewen HP (eds) Lewis Publishers, Boca Raton, p 379-423... 

Cochran JK (1984) The fates of U and Th decay series nuclides in the estuarine environment. In The Estuary as a Filter. Kennedy VS (ed) Academic Press, London, p 179-220 Cochran JK (1992) The oceanic chemistry of the uranium - and thorium - series nuclides. In Uranium-series Disequilibrium Applications to Earth, Marine and Environmental Sciences. Ivanovich M, Harmon RS (eds) Clarendon Press, Oxford, p 334-395 Cochran JK, Masque P (2003) Short-lived U/Th-series radionuclides in the ocean tracers for scavenging rates, export fluxes and particle dynamics. Rev Mineral Geochem 52 461-492 Cochran JK, Carey AE, Sholkovitz ER, Surprenant LD (1986) The geochemistry of uranium and thorium in coastal marine-sediments and sediment pore waters. Geochim Cosmochim Acta 50 663-680 Corbett DR, Chanton J, Burnett W, Dillon K, Rutkowski C. (1999) Patterns of groundwater discharge into Florida Bay. Linrnol Oceanogr 44 1045-1055... 

The principal abiotic processes affecting americium in water is the precipitation and complex formation. In natural waters, americium solubility is limited by the formation of hydroxyl-carbonate (AmOHC03) precipitates. Solubility is unaffected by redox condition. Increased solubility at higher temperatures may be relevant in the environment of radionuclide repositories. In environmental waters, americium occurs in the +3 oxidation state oxidation-reduction reactions are not significant (Toran 1994). 

One of the limitations of the portable field survey instruments in the measurement of americium is that their quantitative accuracy depends on how well the lateral and vertical distribution of americium in the soil compares with the calibration parameters used. These methods can provide a rapid assessment of americium levels on or below surfaces in a particular environment however, laboratory-based analyses of samples procured from these environmental surfaces must be performed in order to ensure accurate quantification of americium (and other radionuclides). This is due, in part, to the strong self absorption of the 59.5 keV gamma-ray by environmental media, such as soil. Consequently, the uncertainty in the depth distribution of americium and the density of the environmental media may contribute to a >30% error in the field survey measurements. Currently, refinements in calibration strategies are being developed to improve both the precision and accuracy (10%) of gamma-ray spectroscopy measurements of americium within contaminated soils (Fong and Alvarez 1997). 

Muggenburg BA, Mewhinney JA, Hahn FF, et al. 1979. Toxicity of inhaled alpha-emitting radionuclides - status report. In Henderson RF, Diel JH, Martinez BS, eds. Inhalation toxicology research institute annual report Lovelace Biomedical and Environmental Research Institute. Albuquerque, NM Inhalation Toxicology Research Institute, 117-121. 

PNL. 2000. Hanford site environmental report for calendar year 1994. Air surveillance, airborne radionuclide concentrations in the Hanford Environs, 1994 compared to values from the previous 5 years. Facility Effluent Monitoring. Pacific Northwest National Laboratory, http //www.pnl/gov/. December 12, 2000. 

Robertson DE, Thomas CW, Perkins RW, et al. 1981. Transuranium and other long-lived radionuclides in the terrestrial environs of nuclear power plants. Electric Power Research Institute, Environmental Physics and Chemistry Program, Energy Analysis and Environment Division, Palo Alto, CA. EA-2045. NTIS/DE82003074. 

ToranL. 1994. Radionuclide contamination in groundwater Is there a problem In Environmental science pollution control series. New York, NY M. Dekker, 437-455. 

ICP-MS (inductively coupled plasma mass spectrometry) is frequently used for determining ultratrace amounts of technetium [9]. In spite of the high cost of the equipment, this detection method is far superior to other radiometric methods as regards sensitivity. When a double focussing high-resolution system is used (HR-ICP-MS) and an ultrasonic nebulizer is introduced [10], the detection limit is in the order 0.002 mBq. The ICP-MS method has been successfully applied to the determination of environmental "Tc as well as to other long-lived radionuclides of neptunium and plutonium in the environment. 

Because estimates of health risk are based on the levels of radionuclides in or near the vicinity properties, the quality of the potential health risk estimates depends upon the availability of appropriate measurement data. Hence, the first steps involved the determination of the appropriate environmental pathways of exposure and developing the source term for the exposure of persons potentially at risk. For our work, the radiological source-term data was based on measurements made principally by the Oak Ridge National Laboratory and the Mound Laboratory. 

Table 5—Radioactive decay scheme data for radionuclides of cerium observed in previous environmental surveillance studies ...

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