strontium-radioisotopes and Emergencies

Gross alpha/beta screening of urine samples was performed to evaluate internal contamination and dose assessment. Data on background radioactivity concentration were extracted by analyzing the urine samples of non-contaminated individuals who had visited a radiation effect medical clinic since 2012. Screening criteria were studied and established for radiation emergencies based on these results. In particular, pure beta-emitting radionuclides (H and Sr) with a high dose conversion factor were considered to be the source of contamination. Moreover, the screening criteria for the general public were determined based on age groups. The liquid scintillation counting method was used for gross alpha/beta radiation counting. A standardized procedure of correction for chemical and color quenching was performed and validated. The gross beta counting method was validated by analyzing standard urine samples. The fluctuation of the screening criteria was large, based on the time elapsed after intake. A screening criterion of 150 Bq L can be applied within 5 d after intake considering the minimum detectable activity. A standard screening criterion set to 250 Bq L will be used as an important reference for decision making and additional monitoring. Although early evaluation and accurate identification of contaminated radionuclides is preferred, these relatively simple criteria were proposed to address radiation emergency situations involving several casualties.

Topics: Beta Particles; Disasters; Emergencies; Humans; Mass Screening; Radiation Monitoring; Radioactive Hazard Release; Radioisotopes; Reference Values; Scintillation Counting; Strontium Radioisotopes; Urinalysis

Radiological or nuclear emergency situations could lead to incorporation of radionuclides by the population. Intakes of radionuclides can be evaluated through measurements of radionuclides present in organs and tissues, or in urinary and/or fecal excretion. In an emergency situation involving a large number of people, the decision to provide medical treatment to an individual will likely be based on a single measurement. For that purpose, the National Council on Radiation Protection and Measurements (NCRP) has presented the Clinical Decision Guide (CDG) quantity, which corresponds to an intake amount of a radionuclide by an individual for which treatment is recommended. However, the NCRP recommends using one-fifth of the CDG for pregnant women and children which could result in an effective or equivalent dose in excess of the dose constraint. Tables of reference urinary excretion concentrations which are associated with an intake of one CDG for inhalation and ingestion intake scenarios of several forms of 60Co, 90Sr, 137Cs, 192Ir, 238Pu, 239Pu and 241Am have been calculated and are presented for the following categories of members of the public: 3 months old, 1 y, 5 y, 10 y, 15 y, adult and pregnant woman.

Topics: Adult; Child; Emergencies; Female; Humans; Plutonium; Radiation Protection; Radioisotopes; Strontium Radioisotopes

In this article, optically stimulated luminescence (OSL) data are presented from integrated circuits (ICs) extracted from mobile phones. The purpose is to evaluate the potential of using OSL from components in personal electronic devices such as smart phones as a means of emergency dosimetry in the event of a large-scale radiological incident. ICs were extracted from five different makes and models of mobile phone. Sample preparation procedures are described, and OSL from the IC samples following irradiation using a (90)Sr/(90)Y source is presented. Repeatability, sensitivity, dose responses, minimum measureable doses, stability and fading data were examined and are described. A protocol for measuring absorbed dose is presented, and it was concluded that OSL from these components is a viable method for assessing dose in the days following a radiological incident.

Topics: Calibration; Cell Phone; Electronics; Emergencies; Humans; Luminescence; Luminescent Measurements; Nonlinear Dynamics; Optically Stimulated Luminescence Dosimetry; Radiation Dosage; Radiation Dosimeters; Radioactive Hazard Release; Reproducibility of Results; Strontium Radioisotopes; Thermoluminescent Dosimetry; Yttrium Radioisotopes

After a radiological or nuclear incident, it is necessary to give a prompt response and to know the number of persons exposed to internal contamination, to evaluate the contamination levels in each person and even and to identify the radionuclides involved. In vitro laboratories routine monitoring measurements employed to quantify (90)Sr and actinides in urine require radiochemical separation and long counting time, which implies a minimum of 1 or 2 weeks to obtain the results, respectively. In this work, rapid radiochemical separation method applied directly to urine samples is presented. It is based on minimal sample preparation, without co-precipitation phase, using extraction resin columns and vacuum box technology. Pu isotopes and (241)Am are isolated, electrodeposited and measured by alpha spectrometry, whereas (90)Sr is measured by liquid scintillation counting. Finally, results of the participation in European Radiation Dosimetry Group intercomparison on Emergency Bioassay exercise and Bundesamt für Strahlenschutz exercise validate the accuracy of this procedure.

Topics: Actinoid Series Elements; Alpha Particles; Americium; Biological Assay; Californium; Emergencies; Europe; Humans; Isotopes; Laboratories; Plutonium; Radiation Monitoring; Radiochemistry; Radioisotopes; Radiometry; Reproducibility of Results; Spectrum Analysis; Strontium Radioisotopes

This study explores the possibility of developing a field-deployable (90)Sr detector for rapid lung counting in emergency situations. The detection of beta-emitters (90)Sr and its daughter (90)Y inside the human lung via bremsstrahlung radiation was performed using a 3″ × 3″ NaI(Tl) crystal detector and a polyethylene-encapsulated source to emulate human lung tissue. The simulation results show that this method is a viable technique for detecting (90)Sr with a minimum detectable activity (MDA) of 1.07 × 10(4) Bq, using a realistic dual-shielded detector system in a 0.25-µGy h(-1) background field for a 100-s scan. The MDA is sufficiently sensitive to meet the requirement for emergency lung counting of Type S (90)Sr intake. The experimental data were verified using Monte Carlo calculations, including an estimate for internal bremsstrahlung, and an optimisation of the detector geometry was performed. Optimisations in background reduction techniques and in the electronic acquisition systems are suggested.

Topics: Electromagnetic Radiation; Emergencies; Humans; Lung; Monte Carlo Method; Strontium Radioisotopes; Yttrium Radioisotopes

This paper describes the development of methods for the rapid screening of gross alpha (GA) and gross beta (GB) radioactivity in liquid foods, specifically, Tang drink mix, apple juice, and milk, as well as screening of GA, GB, and gamma radioactivity from surface deposition on apples. Detailed procedures were developed for spiking of matrices with (241)Am (alpha radioactivity), (90)Sr/(90)Y (beta radioactivity), and (60)Co, (137)Cs, and (241)Am (gamma radioactivity). Matrix stability studies were performed for 43 days after spiking. The method for liquid foods is based upon rapid digestion, evaporation, and flaming, followed by gas proportional (GP) counting. For the apple matrix, surface radioactivity was acid-leached, followed by GP counting and/or gamma spectrometry. The average leaching recoveries from four different apple brands were between 63% and 96%, and have been interpreted on the basis of ion transport through the apple cuticle. The minimum detectable concentrations (MDCs) were calculated from either the background or method-blank (MB) measurements. They were found to satisfy the required U.S. FDA's Derived Intervention Levels (DILs) in all but one case. The newly developed methods can perform radioactivity screening in foods within a few hours and have the potential to capacity with further automation. They are especially applicable to emergency response following accidental or intentional contamination of food with radioactivity.

Topics: Alpha Particles; Analytic Sample Preparation Methods; Beverages; Calibration; Cesium Radioisotopes; Cobalt Radioisotopes; Digestion; Emergencies; Food Contamination, Radioactive; Gamma Rays; Malus; Radioactivity; Radioisotopes; Spectrometry, Gamma; Strontium Radioisotopes; Yttrium Radioisotopes

The question arises as to whether radiation standards and guidelines set for adults are sufficiently protective of children. To answer this question, published literature values have been used to calculate radiation doses to children and adults from external and internal exposure to a suite of 30 radionuclides commonly found in the environment. It was found that older children and adults face about the same degree of risk from external radiation exposures, although doses may be ∼30 % elevated for infants due to their smaller body size. Inhalation risks in children are to a large degree offset by lower breathing rates and it is only in the case of iodine isotopes that children are more at risk. Ingestion of contaminated food products is more complex. Isotopes of iodine and the bone-seeking elements strontium and radium can give radiation doses up to an order of magnitude higher than for adults.

Topics: Adolescent; Adult; Child; Child, Preschool; Emergencies; Humans; Infant; Iodine Radioisotopes; Nuclear Energy; Radiation Injuries; Radiation Protection; Radioactive Fallout; Radium; Risk Assessment; Strontium Radioisotopes