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Kumar R.,Health Physics Laboratory | Yadav J.R.,Health Physics Laboratory | Rao D.D.,Bhabha Atomic Research Center
Journal of Radioanalytical and Nuclear Chemistry | Year: 2011

Bioassay technique is used for the estimation of actinides present in the body based on their excretion rate through body fluids. For occupational radiation workers urine assay is the preferred method for monitoring of chronic internal exposure. Determination of low concentrations of actinides such as plutonium, americium and uranium at low level of mBq in urine by alpha spectrometry requires pre-concentration of large volumes of urine. This article deals with standardization of analytical method for the determination of 241Am isotope in urine samples using Extraction Chromatography (EC) and 243Am tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of americium along with calcium phosphate. This precipitate after treatment is further subjected to calcium oxalate co-precipitation. Separation of Am was carried out by EC column prepared by PC88-A (2-ethyl hexyl phosphonic acid 2-ethyl hexyl monoester) adsorbed on microporous resin XAD-7 (PC88A-XAD7). Am-fraction was electro-deposited and activity estimated using tracer recovery by alpha spectrometer. Ten routine urine samples of radiation workers were analyzed and consistent radiochemical recovery was obtained in the range 44-60% with a mean and standard deviation of 51 and 4.7% respectively. © 2011 Akadémiai Kiadó, Budapest, Hungary. Source


Kumar R.,Health Physics Laboratory | Yadav J.R.,Health Physics Laboratory | Rao D.D.,Health Physics Laboratory | Chand L.,Bhabha Atomic Research Center
Journal of Radioanalytical and Nuclear Chemistry | Year: 2010

Bioassay technique is used for the estimation of actinides present in the body based on their excretion rate through body fluids. For occupational radiation workers urine assay is the preferred method for monitoring of chronic internal exposure. Determination of low concentrations of actinides such as plutonium, americium and uranium at low level of mBq in urine by alpha spectrometry requires pre-concentration of large volumes of urine. This paper deals with standardization of analytical method for the determination of Pu-isotopes in urine samples using anion exchange resin and 236Pu tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of plutonium along with calcium phosphate. Separation of Pu was carried out by Amberlite, IRA-400, anion exchange resin. Pu-fraction was electrodeposited and activity estimated using tracer recovery by alpha spectrometer. Twenty routine urine samples of radiation workers were analyzed and consistent radiochemical tracer recovery was obtained in the range 74-96% with a mean and standard deviation of 85 and 6% respectively. © 2010 Akadémiai Kiadó, Budapest, Hungary. Source


Yadav J.R.,Health Physics Laboratory | Rao D.D.,Health Physics Laboratory | kumar R.,Health Physics Laboratory | Aggarwal S.K.,Bhabha Atomic Research Center
Applied Radiation and Isotopes | Year: 2011

Fission track analysis (FTA) technique for the determination of 239Pu excreted through urine has been standardized using blank samples, tracer and 239Pu spikes. Double stage anion exchange separation protocol has been applied and an average radiochemical recovery of 239Pu of 18% was obtained. An average track registration efficiency of 11 tracks per γBq of 239Pu, irradiated to 0.35×1017 neutron fluence was established. Reagent blank urine samples from 11 controlled subjects were analyzed by FTA and an average of 149±14 tracks was obtained. Minimum detectable activity of 34γBqL-1 of urine sample was obtained and will be useful for monitoring chronic exposure cases handling MOX fuel. © 2011 Elsevier Ltd. Source


Kumar R.,Health Physics Laboratory | Dubla R.,Health Physics Laboratory | Yadav J.R.,Health Physics Laboratory | Rao D.D.,Bhabha Atomic Research Center
Journal of Radioanalytical and Nuclear Chemistry | Year: 2013

The conventional method used for estimation of Pu-isotopes in urine samples involves anion exchange resin followed by alpha spectrometry, which takes nearly one working week for complete sample analysis. Since the results of the analysis form an important input for decision making by the plant authorities, it is always preferable to reduce overall analysis time for the estimation of Pu-isotopes in bioassay samples. This paper deals with standardization of a relatively faster method for estimation of Pu-isotopes in bioassay samples using TEVA resin and 236Pu tracer for radiochemical recovery. The method involves oxidation of urine followed by co-precipitation of plutonium along with calcium phosphate and separation of Pu was carried out using TEVA resin. Pu-fraction was electrodeposited and activity estimated using tracer recovery by alpha spectrometer. Routine urine samples of radiation workers were analyzed and consistent radiochemical tracer recovery was obtained in the range 65-87 % with a mean and SD of 75 and 7.4 %, respectively. The standardized chromatographic technique reduces the analysis time by about 1 day as compared to conventional method for estimation of Pu-isotopes in urine samples. © 2012 Akadémiai Kiadó, Budapest, Hungary. Source

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