Plutonium in urine

Epov, V. N., Benkhedda, K., Cornett, R. J., and Evans, R. D., Rapid determination of plutonium in urine using flow injection on-line preconcentration and inductively coupled plasma mass spectrometry, J. Anal. At. Spectrom., 20, 424-430, 2005. 

James, M.R., Wayman, T., Stellmacher, K. and Hall, R.J.B., The determination of plutonium in urine by electro-thermal vaporisation inductively coupled mass spectrometry (ETV-ICP-MS), presented at 3rd Surrey Conference on Plasma Source Mass Spectrometry, Manchester, England, July 1989. 

Priest, N. D., Pich, G. M., Fifield, L. K., and Cresswell, R. G. 1999. Accelerator mass spectrometry for the detection of ultra-low levels of plutonium in urine, including that excreted after the ingestion of Irish sea sediments. RadiatRes 152(6), S16-S18. 

Biomarkers of exposure to plutonium include the presence of plutonium in urine, which is identified by measuring alpha activity. From the levels of radioactivity in the urine, body burdens of plutonium may be estimated by the use of models. Body burdens of plutonium in several populations, including workers at Los Alamos National Laboratory, the Rocky Flats facility, and the Hanford facility, have been estimated from urinalysis data. However, whole body burdens determined from selected tissues obtained at autopsy have generally been lower than those estimated from urinalysis data (Voelz et al. 1979). The presence of radioactivity from plutonium in urine is specific to plutonium exposure. Plutonium may be found in the urine after any exposure duration (e.g., acute, intermediate, chronic). Although it can be assumed that exposure to greater levels of plutonium would result in the presence of greater levels of radioactivity in the urine, no information was located to directly quantify this relationship. 

Sensitive methods for analysis of plutonium in urine are particularly important for estimating occupational plutonium body burdens. Routinely available instrumentation, such as the alpha spectrometer, can readily detect these low concentrations. More sensitive methods are commonly required for urine samples in order to assess chronic exposures to plutonium. These low detection limits were first achieved in the past by nuclear emulsion track counting (see Table 6-1). In this method, the electrodeposited sample is exposed to nuclear track film, subsequent to the isolation of plutonium. The alpha-particle emitting isotopes of plutonium will leave tracks on the film which are counted to quantify the amount of plutonium. Nuclear emulsion track counting has been used in the past to measure plutonium concentrations in the urine of workers at a nuclear reactor plant (Nielsen and Beasley 1980). A type of scintillation counting has been used to measure plutonium-239 and americium-241 in animal tissues (NCRP 1985). 

L. C. Schwendiman and J. W. Healy, "Nuclear-Track Technique for Low-Level Plutonium in Urine," Nucleonics 78 (1958),... 

Procedure 23. Determination of Plutonium in Urine by Anion Exchange E. D. 

Procedure 24. Determination of Plutonium in Urine by Co-cryataXlization with Potassium Rhodizonate W. H. Shipman and H. V. Weiss (Ref. 374)... 

For some applications, precipitation and co-precipitation, which is often incomplete, is utilized. As an example, for trace matrix separation the procedure for plutonium determination by ICP-SFMS in urine after trace matrix separation is summarized in Figure 6.29.86 87 The limit of detection for 239 Pu ultratrace determination in one litre of urine based on enrichment factor of 100 using the DIHEN in ICP-SFMS was 1.02- 10 18g mF1.86... 

Clinical management can potentially reduce the effects of plutonium intake, although the effectiveness can be highly variable. Administration of the calcium salt of diethylenetriaminepentaacetic acid (DTPA) can accelerate removal of soluble forms of plutonium from body fluids and recent deposits. It is unable to remove intracellular deposits or activity buried in bone and must therefore be administered as soon as possible after an intake. In a review of 18 patients exposed to plutonium, americium, or curium, the US Food and Drug Administration concluded that administration of 1 g Ca-DTPA in 5 ml sterile aqueous solution, either by intravenous injection or as a nebulized inhalation dose, increased the rate of radioactivity elimination in urine by an average of 39-fold. Daily maintenance doses of Zn-DTPA resulted in continued elimination of radioactivity. 

For wounds, any detectable plutonium in the wound or in spot urine samples should warrant considering administration of DTPA. If the activity in the wound is > 5 nCi, excision of tissue should also be considered. 

Arsenazo III was used to determine natural uranium in urine [6] and simultaneous determination of uranium and plutonium at trace levels in process streams by derivative spectrophotometry [7]. 

J. Plutonium in an urine sample is soaked into a photographic emulsion so that the emulsion increases its volume by 20%. The 12 im thick emulsion is dried to original thickness and then left in darkness for 24 h. After development, a-tracks are counted and an average of 2356 tracks cm found. If the plutonium consists of 67% and 33% Pu, what was the plutonium concentration in the urine ... 

Ting, B. G., Pappas, R. S., and Paschal, D. C. 2003. Rapid analysis for plutonium-239 in urine by magnetic sector inductively coupled plasma-mass spectrometry using Aridus desolvation introduction system. J Anal Atom Spectrom 18(7), 795-797. 

Some of the plutonium absorbed into the body leaves the body in urine. The rate of plutonium removal from the tissues of the body is very slow, however, occurring over years. Most of the plutonium that stays in the body is found in the lungs, liver, and skeleton. You may find more information about this subject in Chapter 2. 

There are tests available that can reliably measure the amount of plutonium in a urine sample even at very low levels. These measurements can be used to estimate the total amount of plutonium that is carried by the body. However, these measurements cannot be used to directly determine the levels to which the person was exposed or to predict the potential for health effects. In addition, there are tests to measure plutonium in soft tissues (such as body organs), feces, bones, and milk. These tests are not routinely available in your doctor s office because special laboratory equipment is required. You can find more information on methods used to measure levels of plutonium in Chapters 2 and 6. 

Little information is known about the excretion of plutonium in humans after exposure through other routes. From terminally ill humans who were administered an intravenous injection of plutonium it appeared that the major route of elimination was in the urine (Langham et al. 1980). The biological half-time in these individuals was estimated to be 118 years and the retention half- time in the liver was estimated to be greater than 1 year. Data from humans occupationally exposed through wounds indicated that excretion patterns could not be predicted following this type of exposure (Hammond and Putzier 1964). 

Biomarkers of Exposure and Effect. Currently, the only biomarker of exposure that has been identified is the presence of radioactivity, released by plutonium, in the urine. The presence of this activity in the urine is specific to plutonium exposure and can be used to monitor short- term, intermediate, or long-term exposure. Although the detection of plutonium radioactivity in the urine is not a direct measurement of exposure, estimates may be derived using mathematical models. 

Exposure Levels in Humans.Plutonium is measurable in urine and in lung, liver, and bone tissues obtained from autopsy. It is plausible to expect that occupationally exposed populations are routinely biomonitored through urinalysis. However, such data are not made available and are needed to quantify exposure to these individuals. In addition, no information is available on biomonitoring of individuals around NPL sites where plutonium has been found or of the general public. This information is needed so that exposure to these populations may be quantified. 

Methods used for concentrating plutonium in a sample by a carrier are often specific to one oxidation state of the plutonium. For example, the classical bismuth phosphate-lanthanum fluoride method of concentrating plutonium from urine samples is specific to plutonium in the tri- and tetravalent states and will leave plutonium(VI) in solution. The fate of the various oxidation states of plutonium in man is not well understood and analysis procedures must insure reduction or oxidation of plutonium into appropriate oxidation states. Liver and kidney samples may contain metals (e.g., iron) which may greatly reduce chemical yields during the final electrodeposition step (Bernhardt 1976). 

Methods for Determining Biomarkers of Exposure and Effect.There are methods available for measuring the isotopes of plutonium in biological samples. The measurement of plutonium in the urine is considered a biomarker of exposure to plutonium. Methods are available to detect plutonium in the urine. However, no information was available concerning the reliability of these methods for... 

Because of the high radiotoxicity of most of the actinide nuclides, only very limited studies of the biokinetics of plutonium and other important actinides are possible in human volunteers. As our information about the long-term retention of actinides is limited, there is interest in the possible use of stable lanthanide elements as surrogates for the actinides for long-term biokinetic studies in humans. The aim of such studies is to inject appropriate stable isotopes of lanthanides such as cerium, europium, and gadolinium into human volunteers and then to measure the excretion of the lanthanide in urine and faeces by mass spectrometry, charged-particle activation analysis or similar methods. Also, limited human studies can also be carried out using small doses of appropriate lanthanide radionuclides (Bailey 1989). 

Such studies as are available indicate that plutonium, americium, and curium are cleared through the kidneys and excreted in the urine as citrate complexes, whereas uranyl ion is excreted as a bicarbonate complex. Although there is by now a considerable body of information on the rate of excretion of plutonium in the urine as influenced by a variety of additives and presumptive therapeutic agents, much remains to be learned about the chemistry of the elimination of the actinide elements through the kidney. 

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