Comparative biokinetics of radiogallium and radioindium in mice

International Nuclear Information System (INIS)

Tsui, B.M.W.; Lathrop, K.A.

1978-01-01

The biokinetics of radiogallium and radioindium in normal mice are compared using the compartmental modelling analysis. The rate constants obtained provide useful information in understanding the physiological and biochemical kinetics of radionuclides in the intact object. A comparison of the compartmental models for gallium and indium reveals the similarities and differences between the biokinetics of the two radionuclides. Furthermore, the results provide valuable information and guidance for human studies and clinical use

Biokinetic models for the metabolism of uranium: an overview

International Nuclear Information System (INIS)

Bertelli, Luiz; Lipsztein, Joyce L.; Melo, Dunstana R.; Puerta, Anselmo; Wrenn, McDonald E.

1997-01-01

This work reviews the main experiments involving uranium injection and inhalation into several animal species and those associated with humans as well. The literature was carefully selected to involve the uranium intake, distribution and excretion in humans and mammals. The available biokinetic models for the uranium metabolism, proposed by ICRP in Publications 2, 30 and 69, were shortly described and tested against the data. Human data which incorporates measurements of urine, autopsy and biopsy samples were also used completing the review of models associated with the systemic part. (author). 21 refs., 4 figs

Reliability of a new biokinetic model of zirconium in internal dosimetry: part II, parameter sensitivity analysis.

Science.gov (United States)

Li, Wei Bo; Greiter, Matthias; Oeh, Uwe; Hoeschen, Christoph

2011-12-01

The reliability of biokinetic models is essential for the assessment of internal doses and a radiation risk analysis for the public and occupational workers exposed to radionuclides. In the present study, a method for assessing the reliability of biokinetic models by means of uncertainty and sensitivity analysis was developed. In the first part of the paper, the parameter uncertainty was analyzed for two biokinetic models of zirconium (Zr); one was reported by the International Commission on Radiological Protection (ICRP), and one was developed at the Helmholtz Zentrum München-German Research Center for Environmental Health (HMGU). In the second part of the paper, the parameter uncertainties and distributions of the Zr biokinetic models evaluated in Part I are used as the model inputs for identifying the most influential parameters in the models. Furthermore, the most influential model parameter on the integral of the radioactivity of Zr over 50 y in source organs after ingestion was identified. The results of the systemic HMGU Zr model showed that over the first 10 d, the parameters of transfer rates between blood and other soft tissues have the largest influence on the content of Zr in the blood and the daily urinary excretion; however, after day 1,000, the transfer rate from bone to blood becomes dominant. For the retention in bone, the transfer rate from blood to bone surfaces has the most influence out to the endpoint of the simulation; the transfer rate from blood to the upper larger intestine contributes a lot in the later days; i.e., after day 300. The alimentary tract absorption factor (fA) influences mostly the integral of radioactivity of Zr in most source organs after ingestion.

Recent developments in biokinetic models and the calculation of internal dose coefficients

International Nuclear Information System (INIS)

Fell, T.P.; Phipps, A.W.; Kendall, G.M.; Stradling, G.N.

1997-01-01

In most cases the measurement of radioactivity in an environmental or biological sample will be followed by some estimation of dose and possibly risk, either to a population or an individual. This will normally involve the use of a dose coefficient (dose per unit intake value) taken from a compendium. In recent years the calculation of dose coefficients has seen many developments in both biokinetic modelling and computational capabilities. ICRP has recommended new models for the respiratory tract and for the systemic behavior of many of the more important elements. As well as this, a general age-dependent calculation method has been developed which involves an effectively continuous variation of both biokinetic and dosimetric parameters, facilitating more realistic estimation of doses to young people. These new developments were used in work for recent ICRP, IAEA and CEC compendia of dose coefficients for both members of the public (including children) and workers. This paper presents a general overview of the method of calculation of internal doses with particular reference to the actinides. Some of the implications for dose coefficients of the new models are discussed. For example it is shown that compared with data in ICRP Publications 30 and 54: the new respiratory tract model generally predicts lower deposition in systemic tissues per unit intake; the new biokinetic models for actinides allow for burial of material deposited on bone surfaces; age-dependent models generally feature faster turnover of material in young people. All of these factors can lead to substantially different estimates of dose and examples of the new dose coefficients are given to illustrate these differences. During the development of the new models for actinides, human bioassay data were used to validate the model. Thus, one would expect the new models to give reasonable predictions of bioassay quantities. Some examples of the bioassay applications, e.g., excretion data for the

Relevance of the ICRP biokinetic model for dietary organically bound tritium

International Nuclear Information System (INIS)

Trivedi, A.

1999-10-01

Ingested dietary tritium can participate in metabolic processes, and become synthesized into organically bound tritium in the tissues and organs. The distribution and retention of the organically bound tritium throughout the body are much different than tritium in the body water. The International Commission on Radiological Protection (ICRP) Publication 56 (1989) has a biokinetic model to calculate dose from the ingestion of organically bound dietary tritium. The model predicts that the dose from the ingestion of organically bound dietary tritium is about 2.3 times higher than from the ingestion of the same activity of tritiated water. Under steady-state conditions, the calculated dose rate (using the first principle approach) from the ingestion of dietary organically bound tritium can be twice that from the ingestion of tritiated water. For an adult, the upper-bound dose estimate for the ingestion of dietary organically bound tritium is estimated to be close to 2.3 times higher than that of tritiated water. Therefore, given the uncertainty in the dose calculation with respect to the actual relevant dose, the ICRP biokinetic model for organically bound tritium is sufficient for dosimetry for adults. (author)

Reliability of Current Biokinetic and Dosimetric Models for Radionuclides: A Pilot Study

Energy Technology Data Exchange (ETDEWEB)

Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; Meck, Robert A. [U.S. Nuclear Regulatory Commission

2008-10-01

This report describes the results of a pilot study of the reliability of the biokinetic and dosimetric models currently used by the U.S. Nuclear Regulatory Commission (NRC) as predictors of dose per unit internal or external exposure to radionuclides. The study examines the feasibility of critically evaluating the accuracy of these models for a comprehensive set of radionuclides of concern to the NRC. Each critical evaluation would include: identification of discrepancies between the models and current databases; characterization of uncertainties in model predictions of dose per unit intake or unit external exposure; characterization of variability in dose per unit intake or unit external exposure; and evaluation of prospects for development of more accurate models. Uncertainty refers here to the level of knowledge of a central value for a population, and variability refers to quantitative differences between different members of a population. This pilot study provides a critical assessment of models for selected radionuclides representing different levels of knowledge of dose per unit exposure. The main conclusions of this study are as follows: (1) To optimize the use of available NRC resources, the full study should focus on radionuclides most frequently encountered in the workplace or environment. A list of 50 radionuclides is proposed. (2) The reliability of a dose coefficient for inhalation or ingestion of a radionuclide (i.e., an estimate of dose per unit intake) may depend strongly on the specific application. Multiple characterizations of the uncertainty in a dose coefficient for inhalation or ingestion of a radionuclide may be needed for different forms of the radionuclide and different levels of information of that form available to the dose analyst. (3) A meaningful characterization of variability in dose per unit intake of a radionuclide requires detailed information on the biokinetics of the radionuclide and hence is not feasible for many infrequently

A biokinetic model of inhaled Cm compounds in dogs: Application to human exposure data

International Nuclear Information System (INIS)

Guilmette, R.A.; Mewhinney, J.A.

1989-01-01

Curium isotopes are major by-products in irradiated nuclear reactor fuel and comprise a significant fraction of the alpha-emitting radionuclide inventory. Although little use is currently being made of purified Cm sources, such usage is possible if reprocessing of spent fuel becomes feasible. Because little information is available on the biokinetics and dosimetry of inhaled Cm compounds, a study was conducted in which adult beagle dogs received a single inhalation exposure to either a monodisperse aerosol of 244Cm2O3 (1.4 micron activity median aerodynamic diameter [AMAD]; sigma g = 1.16) or a polydisperse aerosol of 244Cm (NO3)3 (1.1 micron AMAD; sigma g = 1.74). At times ranging from 4 h to 2 y after exposure, animals were sacrificed and their tissues analyzed for Cm content. The data describing the uptake and retention of 244Cm in the different organs and tissues and the measured rates of excretion of these dogs formed the basis on which a biokinetic model of Cm metabolism was constructed. This Cm model was based on a previously published model of the biokinetics of 241Am that was shown to be applicable to data from human cases of inhalation exposure to 241Am aerosols. This Cm model was found to be adequate to describe the biological distribution of Cm in dogs and was also applied to the sparse data from humans. Reasonable agreement was found between the model predictions for lung retention of Cm and for urinary excretion patterns in humans

A physiological biokinetic model for the [7(N)-3H]-cholesterol dosimetry

International Nuclear Information System (INIS)

Oliveira, Adriano dos Santos; Martins, Joao Francisco Trencher; Velo, Alexandre Franca; Hamada, Margarida M.; Mesquita, Carlos Henrique de

2015-01-01

Cardiovascular diseases (CVD) are a major source of deaths worldwide according to WHO (World Health Organization). It is well-known that the change of the level of plasma lipoproteins, which are responsible for the cholesterol transport in the bloodstream, is a main cause of these diseases. For this reason, to know the biokinetic parameters of plasma lipoproteins and quantifies them is important to correct and deepen the understanding of associated diseases. The main objective of this work is to provide a biokinetic model in order to estimate the radiometric dose, due to the intake of [7(N) -3 H] –Cholesterol in physiological issues, in metabolic studies. The internal dosimetry is important to know the biological effects of radiation. The model was based on Schwartz et al (2004), using parameters for the plasmatic lipoproteins and ICRP 30 (1979) gastrointestinal tract; the dose in the compartments were calculated using the MIRD methodology and the compartmental analysis by Matlab® software. The coefficients were estimated for an adult phantom with a body mass of 73.3 kg. (author)

Estimation of parameters biokinetics from the resolution of a model compartment for I-131. Application to a patient with thyroid carcinoma hemodialysis

International Nuclear Information System (INIS)

Garcia, R.; Jimenez Feltstrom, D.; Luis dimon, F. J.; Sanchez Carmona, G.; Herrador Cordoba, M.

2013-01-01

This work aims to define a biokinetic model for the I-131, and solve it for different conditions of the patient or person affected (normal, with cancer of the thyroid or hyperthyroid). Solve the model in the case of a patient treated with I-131 for ablation of thyroid remnants with undergoing renal insufficiency and hemodialysis . Get the parameters Biokinetic this model for different situations. (Author)

Investigation on biokinetics of 134Cs and 241Am radionuclides in three different organisms and a new evaluation by using discrete time model

International Nuclear Information System (INIS)

Guengoer, N.

1999-05-01

In this study, 134 Cs and 241 Am biokinetic experiments have been observed originally for Black Sea condition with using the gastropod Patella coerulea and the macro algae Enteremorpha linza and the common mussel Mytilus galloprovlncialis as bio indicator organisms. The experiments that have at least three originality, have been carried out very carefully and biokinetic parameters have been calculated by using classical model. The results are compared with the proportionally similar experiments in the literature globally. In this thesis, a new model application has proposed for the biokinetic evaluation for loss experiments of organisms. That is discrete time model. Loss experiments can be evaluated proportionally in a quick and easy way by using this model. Then, it can be observed that the calculated decreasing factor (r) by discrete time model, shows the loss process quality. Moreover, the loss experiments can be stopped when the decreasing factor goes to 1. So, the loss experiment can be evaluated rapidly and quickly with the adequate reliability by using discrete time model. Furthermore, the loss process in the organisms becomes slower and biologic half-lives becomes longer, when the decreasing factor (r) goes to 1. On the other hand, the biological depuration rate (k) goes to nearly zero. So, the proposed discrete time model that is applied in this thesis originally for biokinetic, can be evident that it has an adequate reliability for the biokinetic evaluation

Stable tracer investigations in humans for assessing the biokinetics of ruthenium and zirconium radionuclides

International Nuclear Information System (INIS)

Veronese, I.; Cantone, M.C.; Giussani, A.; Maggioni, T.; Birattari, C.; Bondardi, M.; Groppi, F.; Garlaschelli, I.; Werner, E.; Roth, P.; Hoellriegl, V.; Louvat, P.; Felgenhauer, N.; Zilker, Th.

2003-01-01

The interest in the biokinetics of ruthenium and zirconium in humans is justified by the potential radiological risk represented by their radionuclides. Only a few data related to the biokinetics of ruthenium and zirconium in humans are available and, accordingly, the biokinetic models currently recommended by the ICRP for these elements are mainly based on data from animal experiments. The use of stable isotopes as tracers, coupled with a proper analytical technique (nuclear activation analysis with protons) for their determination in biological samples, represents an ethically acceptable methodology for biokinetic investigations, being free from any radiation risk for the volunteer subjects. In this work, the results obtained in eight biokinetic investigations for ruthenium, conducted on a total of three healthy volunteers, and six for zirconium, performed on a total of three subjects, are presented and compared to the predictions of the ICRP models. (author)

Prediction of blood lead levels in children before and after remediation of soil samples in the upper Meza Valley, Slovenia.

Science.gov (United States)

Jez, Erika; Lestan, Domen

2015-10-15

The Meza Valley, Slovenia, has been contaminated by Pb smelting, resulting in an epidemic of lead poisoning in childhood. The potential of remediation with EDTA soil washing to mitigate the risk from Pb poisoning was investigated by applying the Integrated Exposure Uptake Bio-kinetic (IEUBK) model. Soils from 79 locations were collected and the total and bio-accessible Pb concentrations were determined before and after extraction with 60 mmol kg(-1) EDTA. Extraction reduced the soil Pb concentration in towns of Mezica, Zerjav and Crna by 53, 67 and 62%, respectively, and the concentration of in vitro bio-accessible Pb in the simulated human gastric phase by 2.6-, 3.2- and 2.9-times, respectively. The predictions of the IEUBK model based on Pb contamination data were verified with data on blood Pb levels in children. The IEUBK model predicted that, after soil remediation, the number of locations at which the expected blood Pb level in children was higher than the stipulated 10 μg d L(-1) would decrease by 90, 38 and 91% in the towns of Mezica, Zerjav and Crna, respectively. The results confirmed the feasibility of soil washing with EDTA as an efficient remediation measure in Mezica and Crna and advice for soil capping/removal for the most polluted town of Zerjav. Copyright © 2015 Elsevier B.V. All rights reserved.

The biokinetics of Rhuthenium and Zirconium radionuclides in humans studied with stable tracers

International Nuclear Information System (INIS)

Veronese, I.; Cantone, M.C.; Giussani, A.

2002-01-01

The assessment of the internal radiation dose delivered by radionuclides incorporated in the human body after accidental release into the environment requires the use of suitable biokinetic models. These models describe the absorption of radionuclides into the blood circulation, their distribution and retention in various organs and tissues, and the excretion routes. Biokinetic models are also employed for interpreting bioassay measurements in exposed subjects, like activity concentration measurements in body fluids (e.g. urine, blood), in order to estimate the incorporated amount of radioactive substances. The reliability of a biokinetic model is closely linked to the available experimental data used to develop the model itself. Biokinetic data for human subjects are available for most essential elements, as well as for some important non-essential elements such as caesium, lead, radium, uranium, americium and plutonium. For many other radionuclides, either very little or no information is available from human studies, and the respective models must be derived from other sources. These may include results from studies in animals, comparative data on the behaviour of similar radionuclides or chemical analogues in vitro. Biokinetic models developed from such a variety of data sources can be applied to humans only with a limited degree of confidence. The availability of data directly obtained on human subjects is therefore fundamental to set up more reliable and realistic models. Ruthenium and zirconium are among the elements characterised by a serious lack of reliable data in humans

Strontium biokinetic model for the pregnant woman and fetus: application to Techa River studies

International Nuclear Information System (INIS)

Shagina, N B; Tolstykh, E I; Degteva, M O; Fell, T P; Harrison, J D

2015-01-01

A biokinetic model for strontium (Sr) for the pregnant woman and fetus (Sr-PWF model) has been developed for use in the quantification of doses from internal radiation exposures following maternal ingestion of Sr radioisotopes before or during pregnancy. The model relates in particular to the population of the Techa River villages exposed to significant amounts of ingested Sr radioisotopes as a result of releases of liquid radioactive wastes from the Mayak plutonium production facility (Russia) in the early 1950s. The biokinetic model for Sr metabolism in the pregnant woman was based on a biokinetic model for the adult female modified to account for changes in mineral metabolism during pregnancy. The model for non-pregnant females of all ages was developed earlier with the use of extensive data on 90 Sr-body measurements in the Techa Riverside residents. To determine changes in model parameter values to take account of changing mineral metabolism during pregnancy, data from longitudinal studies of calcium homeostasis during human pregnancy were analysed and applied. Exchanges between maternal and fetal circulations and retention in fetal skeleton and soft tissues were modelled as adaptations of previously published models, taking account of data on Sr and calcium (Ca) metabolism obtained in Russia (Southern Urals and Moscow) relating to dietary calcium intakes, calcium contents in maternal and fetal skeletons and strontium transfer to the fetus. The model was validated using independent data on 90 Sr in the fetal skeleton from global fallout as well as unique data on 90 Sr-body burden in mothers and their still-born children for Techa River residents. While the Sr-PWF model has been developed specifically for ingestion of Sr isotopes by Techa River residents, it is also more widely applicable to maternal ingestion of Sr radioisotopes at different times before and during pregnancy and different ages of pregnant women in a general population. (paper)

A physiological skeletal model for radionuclide and stable element biokinetics in children and adults

International Nuclear Information System (INIS)

Richardson, R.B.

2010-01-01

A physiological skeletal model (PSM) is described that represents the skeletal uptake, retention and clearance of both bone-surface-seeking and bone-volume-seeking radionuclides and stable elements. A key objective of the PSM is to model the higher skeletal growth and bone turnover in infants and children (compared to adults) in order to to account for their greater uptake and cancer risk from bone-seeking contaminants such as lead and plutonium. The PSM is a compartmental model that allows for the incorporation of organic and inorganic material in the bone volume via quiescent bone surfaces, forming bone surfaces and the lacuno-canaliculi system. The model uniquely incorporates a tertiary phase of mineralization via bone fluids. The PSM's structural concepts and biokinetic parameters - such as realistic mass transfers, organ and tissue masses, and bone remodelling half times - are selected mainly on the basis of physiological and anatomical criteria. For brevity, model parameter values or evaluated for adults only. The PSM is an improvement on existing skeletal models that are based more on compartment structures and pathways that rendered good fits to biokinetic data rather than on being anatomically and physiologically accurate. (author)

A physiological biokinetic model for the [7(N)-{sup 3}H]-cholesterol dosimetry

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Adriano dos Santos; Martins, Joao Francisco Trencher; Velo, Alexandre Franca; Hamada, Margarida M.; Mesquita, Carlos Henrique de, E-mail: adriano_oliveira@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2015-07-01

Cardiovascular diseases (CVD) are a major source of deaths worldwide according to WHO (World Health Organization). It is well-known that the change of the level of plasma lipoproteins, which are responsible for the cholesterol transport in the bloodstream, is a main cause of these diseases. For this reason, to know the biokinetic parameters of plasma lipoproteins and quantifies them is important to correct and deepen the understanding of associated diseases. The main objective of this work is to provide a biokinetic model in order to estimate the radiometric dose, due to the intake of [7(N){sup -3}H] –Cholesterol in physiological issues, in metabolic studies. The internal dosimetry is important to know the biological effects of radiation. The model was based on Schwartz et al (2004), using parameters for the plasmatic lipoproteins and ICRP 30 (1979) gastrointestinal tract; the dose in the compartments were calculated using the MIRD methodology and the compartmental analysis by Matlab® software. The coefficients were estimated for an adult phantom with a body mass of 73.3 kg. (author)

Critical review of membrane bioreactor models--part 1: biokinetic and filtration models.

Science.gov (United States)

Naessens, W; Maere, T; Nopens, I

2012-10-01

Membrane bioreactor technology exists for a couple of decades, but has not yet overwhelmed the market due to some serious drawbacks of which operational cost due to fouling is the major contributor. Knowledge buildup and optimisation for such complex systems can significantly benefit from mathematical modelling. In this paper, the vast literature on modelling MBR biokinetics and filtration is critically reviewed. It was found that models cover the wide range of empirical to detailed mechanistic descriptions and have mainly been used for knowledge development and to a lesser extent for system optimisation/control. Moreover, studies are still predominantly performed at lab or pilot scale. Trends are discussed, knowledge gaps identified and interesting routes for further research suggested. Copyright © 2012 Elsevier Ltd. All rights reserved.

Software for biokinetic modeling of the radiopharmaceuticals used in PET

International Nuclear Information System (INIS)

Cordeiro, Leanderson P.; Vieira, Igor F.; Lima, Fernando R.A. de; Vieira, Jose W.

2013-01-01

In this work will be presented the current state of software in development to estimate the dose from PET images. Will be given the main biokinetic models used in PET, as well as the general features of a tool in development, whose current features allow quantitative analysis of compartmental models. Further, the tool allows display images 2D PET (in DICOM format) and quantify the intensity map of regions of interest in counts per second coincidence events. The next step is to insert in the same tool to estimate the activity concentration for ROI and estimate dose from PET images static and / or dynamic

A biokinetic and dosimetric model for the metabolism of uranium

International Nuclear Information System (INIS)

Wrenn, M.E.; Bertelli, L.; Durbin, P.W.; Eckerman, K.F.; Lipsztein, J.L.; Singh, N.P.

1995-10-01

Experiments involving injection and inhalation of uranium compounds into several animal species as well as those associated with humans are described and analyzed. A revised biokinetic and dosimetric model for the metabolism of uranium suitable for bioassay procedures is proposed. The model consists of a systematic part coupled to a model of the respiratory tract. The model has been tested against human data which incorporates in vivo measurements over the chest and measurements of urine, feces, and autopsy and biopsy samples.In particular the lung model of the International Commission on Radiological Protection, Publication 30 ( ICRP-30 ), has been modified in order to provide a model which more nearly predicts urinary excretion in accord with the experiences in humans and animals. We have also tested the data against the new ICRP (LUDEP) lung model. (author). 55 refs., 14 tabs., 33 figs

Intercomparison and biokinetic model validation of radionuclide intake assessment. Report of a co-ordinated research project. 1996-1998

International Nuclear Information System (INIS)

1999-03-01

This TECDOC presents the results of a Co-ordinated Research Project (CRP) on Intercomparison and Biokinetic Model Validation of Radionuclide Intake Assessment, including the conclusions of a Research Co-ordination Meeting held from 6 to 8 July 1998. The present CRP on Intercomparison and Biokinetic Model Validation of Radionuclide Intake Assessment is part of the activities of the IAEA's Occupational Protection programme. The objective of this programme is to promote an internationally harmonized approach for optimizing occupational radiation protection through: the development of guides, within the IAEA's activities for establishing standards for radiation protection, for restricting radiation exposures in the workplace and for applying current occupational radiation protection techniques; and the promotion of application of these guidelines

Biokinetic model for 137 Cs

International Nuclear Information System (INIS)

Melo, Dunstana Rabelo de

1995-01-01

The main objective of this work was to provide a realistic biokinetic model for 137 Cs metabolism. This model was based on the retention of cesium in 57 people contaminated in the Goiania accident, ages 1 to 73 y old, complemented by data obtained in an experiment with beagle dogs, and data taken from the open literature. Cesium is distributed among all tissues and organs of the body. Its main retention site is the skeletal muscle tissue. Mathematically, cesium retention in the body may be described by a sum of three terms exponential equation. The first term represents the fraction which is rapidly eliminated in urine. This fraction is weight dependent (negative correlation). The second term represents the retention of cesium in tissues and organs of the body. For children and adolescents, the second term biological half-life is a function of the weight. For adults, it is correlated with sex. Men present a higher retention of cesium than women. The third term correspond to a retention fraction of the order of 0,1% of the initial body burden. It is characterized by a very long half-life and represents a subcellular retention of cesium in the skeletal muscle tissue. During pregnancy the transfer factor from the mother to the fetus is correlated to the amount of cesium in the blood and it is equal to 1, if the intake of cesium occurs pregnancy. (author)

The biokinetics of uranium migrating from embedded DU fragments

International Nuclear Information System (INIS)

Leggett, R.W.; Pellmar, T.C.

2003-01-01

Military uses of depleted uranium (DU) munitions have resulted in casualties with embedded DU fragments. Assessment of radiological or chemical health risks from these fragments requires a model relating urinary U to the rate of migration of U from the fragments, and its accumulation in systemic tissues. A detailed biokinetic model for U has been published by the International Commission on Radiological Protection (ICRP), but its applicability to U migrating from embedded DU fragments is uncertain. Recently, ) conducted a study at the Armed Forces Radiobiology Research Institute (AFRRI) on the redistribution and toxicology of U in rats with implanted DU pellets, simulating embedded fragments. This paper compares the biokinetic data from that study with the behavior of commonly studied forms of U in rats (e.g., intravenously injected U nitrate). The comparisons indicate that the biokinetics of U migrating from embedded DU is similar to that of commonly studied forms of U with regard to long-term accumulation in kidneys, bone, and liver. The results provide limited support for the application of the ICRP's model to persons with embedded DU fragments. Additional information is needed with regard to the short-term behavior of migrating U and its accumulation in lymph nodes, brain, testicles, and other infrequently studied U repositories

INDOSE V2.1.1, Internal Dosimetry Code Using Biokinetics Models

International Nuclear Information System (INIS)

Silverman, Ido

2002-01-01

A - Description of program or function: InDose is an internal dosimetry code developed to enable dose estimations using the new biokinetic models (presented in ICRP-56 to ICRP71) as well as the old ones. The code is written in FORTRAN90 and uses the ICRP-66 respiratory tract model and the ICRP-30 gastrointestinal tract model as well as the new and old biokinetic models. The code has been written in such a way that the user is able to change any of the parameters of any one of the models without recompiling the code. All the parameters are given in well annotated parameters files that the user may change and the code reads during invocation. As default, these files contains the values listed in ICRP publications. The full InDose code is planed to have three parts: 1) the main part includes the uptake and systemic models and is used to calculate the activities in the body tissues and excretion as a function of time for a given intake. 2) An optimization module for automatic estimation of the intake for a specific exposure case. 3) A module to calculate the dose due to the estimated intake. Currently, the code is able to perform only its main task (part 1) while the other two have to be done externally using other tools. In the future we would like to add these modules in order to provide a complete solution for the people in the laboratory. The code has been tested extensively to verify the accuracy of its results. The verification procedure was divided into three parts: 1) verification of the implementation of each model, 2) verification of the integrity of the whole code, and 3) usability test. The first two parts consisted of comparing results obtained with InDose to published results for the same cases. For example ICRP-78 monitoring data. The last part consisted of participating in the 3. EIE-IDA and assessing some of the scenarios provided in this exercise. These tests where presented in a few publications. It has been found that there is very good agreement

Biokinetics of radionuclides and treatment of accidental intakes

International Nuclear Information System (INIS)

Taylor, D.M.; Stradling, G.N.; Menetrier, F.

2003-01-01

This paper describes the objectives and reviews the progress of EULEP Working Party 5, convened under the auspices of the European Union's Fifth Framework Programme, to 'cluster' two EU-supported contracts, Biokinetics and Dosimetry of Internal Contamination (BIODOS (EU Contract FIS5-1999-00214)) and Radionuclide Biokinetics Database (EULEP) ( RBDATA-EULEP (Concerted Action Contract FIS5-1999-00218), and two non-EU funded projects, Biokinetics of Radionuclides in Human Volunteers (RNHV (non-EU Funded Project) and Treatment of Accidental Intakes of Radionuclides (TAIR (part-funded by EULEP)). (author)

Calibration of hydrodynamic behavior and biokinetics for TOC removal modeling in biofilm reactors under different hydraulic conditions.

Science.gov (United States)

Zeng, Ming; Soric, Audrey; Roche, Nicolas

2013-09-01

In this study, total organic carbon (TOC) biodegradation was simulated by GPS-X software in biofilm reactors with carriers of plastic rings and glass beads under different hydraulic conditions. Hydrodynamic model by retention time distribution and biokinetic measurement by in-situ batch test served as two significant parts of model calibration. Experimental results showed that TOC removal efficiency was stable in both media due to the enough height of column, although the actual hydraulic volume changed during the variation of hydraulic condition. Simulated TOC removal efficiencies were close to experimental ones with low theil inequality coefficient values (below 0.15). Compared with glass beads, more TOC was removed in the filter with plastic rings due to the larger actual hydraulic volume and lower half saturation coefficient in spite of its lower maximum specific growth rate of biofilm, which highlighted the importance of calibrating hydrodynamic behavior and biokinetics. Copyright © 2013 Elsevier Ltd. All rights reserved.

Biokinetics of zinc oxide nanoparticles: toxicokinetics, biological fates, and protein interaction

Directory of Open Access Journals (Sweden)

Choi SJ

2014-12-01

Full Text Available Soo-Jin Choi,1 Jin-Ho Choy2 1Department of Food Science and Technology, Seoul Women's University, 2Center for Intelligent Nano Bio Materials (CINBM, Department of Bioinspired Science and Department of Chemistry and Nanoscience, Ewha Womans University, Seoul, South Korea Abstract: Biokinetic studies of zinc oxide (ZnO nanoparticles involve systematic and quantitative analyses of absorption, distribution, metabolism, and excretion in plasma and tissues of whole animals after exposure. A full understanding of the biokinetics provides basic information about nanoparticle entry into systemic circulation, target organs of accumulation and toxicity, and elimination time, which is important for predicting the long-term toxic potential of nanoparticles. Biokinetic behaviors can be dependent on physicochemical properties, dissolution property in biological fluids, and nanoparticle–protein interaction. Moreover, the determination of biological fates of ZnO nanoparticles in the systemic circulation and tissues is critical in interpreting biokinetic behaviors and predicting toxicity potential as well as mechanism. This review focuses on physicochemical factors affecting the biokinetics of ZnO nanoparticles, in concert with understanding bioavailable fates and their interaction with proteins. Keywords: ZnO nanoparticles, biokinetics, distribution, excretion, fate, interaction

Biokinetics and internal dosimetry of inhaled metal tritide particles

Science.gov (United States)

Wang, Yansheng

1998-12-01

Metal tritides (MT), stable chemical compounds of tritium, are widely used in nuclear engineering facilities. MT particles can be released as aerosols. Inhaling MT particles is a potential occupational radiation hazard. Little information is available on their dissolution behavior, biokinetics, and dosimetry. The objectives of present dissertation are to estimate dissolution rates, to develop biokinetic models, to improve internal dosimetric considerations, and to classify MT materials. This study consisted of three phases: In vitro dissolution in a simulated lung fluid, In vivo rat experiments on retention and clearance, and biokinetic modeling and dosimetric evaluation. There was a supporting study on self- absorption of tritium beta in MT particles. MT materials used in this study were titanium (Ti) and zirconium (Zr) tritides. Results shows considerable self-absorption of beta particles and their energy, even for respirable MT particles smaller than 5 μm. The self-absorption factors should be required for counting MT particle samples and for estimating absorbed dose to tissues. In vitro and in vivo dissolution data indicate that Ti and Zr tritides are poorly soluble materials. Ti tritide belongs to the W class or M type while Zr tritide can be classified as Y class or S type. Due to long retention time of the MT particles, tritium betas directly from the particles contribute over 90% of the absorbed dose to lung. The lung dose contributes most of the effective dose to the whole body. Dissolved tritium including tritiated water (HTO) and organically bound tritium (OBT) has less effect on the lung dose and effective dose. Results on the annual limit on intake (ALI) indicate that the current radiation protection guideline based on HTO is not adequate for inhalation exposure to MT particles and needs to be modified. The biokinetic models developed in this study have predictive powers to estimate the consequences of a human inhalation exposure to MT aerosols. The

Proposal of a new biokinetic model for niobium

International Nuclear Information System (INIS)

Oliveira, Roges

2006-01-01

There are two niobium isotopes generated in nuclear power plants: 95 Nb and 94 Nb. Workers and members of the public are subjects to intake these radionuclides in accident situation. For dose calculation purpose, it is very important to develop a model that describes in a more realistic way the kinetics of niobium inside of the human body. Presently the model adopted by ICRP (ICRP, 1989) is based on animal studies and describes the behavior of niobium in human being in a simple manner. The new model proposal describes the kinetics of the niobium from the intake into the blood until the excretion, doing this in a more realistic form and considering not only data from animals but data from human beings as well. For this objective, a workers group of a niobium extraction and processing industry exposed to stable niobium (93 Nb) in oxide insoluble form with associated uranium, was monitored for uranium and niobium determination in urinary and fecal excretion, by mass spectrometry. Based in the ratios of the niobium concentration in urinary and faecal excretion of this workers and animal data study, a new biokinetic model for niobium was proposed, with the followings modifications relative to ICRP model: a new compartment that represents muscular tissue; the fractions which are deposited into the compartment are modified; a third component in the retention equation of the bone tissue; introduction of recirculation between organs and blood. The new model was applied for a case of accidental intake and described adequately the experimental data

Strontium biokinetic model for the lactating woman and transfer to breast milk: application to Techa River studies

International Nuclear Information System (INIS)

Shagina, N B; Tolstykh, E I; Degteva, M O; Fell, T P; Smith, T J; Harrison, J D

2015-01-01

This paper presents a biokinetic model for strontium metabolism in the lactating woman and transfer to breast milk for members of Techa River communities exposed as a result of discharges of liquid radioactive wastes from the Mayak plutonium production facility (Russia) in the early 1950s. This model was based on that developed for the International Commission for Radiological Protection with modifications to account for population specific features of breastfeeding and maternal bone mineral metabolism. The model is based on a biokinetic model for the adult female with allowances made for changes in mineral metabolism during periods of exclusive and partial breast-feeding. The model for females of all ages was developed earlier from extensive data on 90 Sr-body measurements for Techa Riverside residents. Measurements of 90 Sr concentrations in the maternal skeleton and breast milk obtained in the1960s during monitoring of global fallout in the Southern Urals region were used for evaluation of strontium transfer to breast and breast milk. The model was validated with independent data from studies of global fallout in Canada and measurements of 90 Sr body-burden in women living in the Techa River villages who were breastfeeding during maximum 90 Sr-dietary intakes. The model will be used in evaluations of the intake of strontium radioisotopes in breast milk by children born in Techa River villages during the radioactive releases and quantification of 90 Sr retention in the maternal skeleton. (paper)

Uranium: biokinetics and toxicity

International Nuclear Information System (INIS)

Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A.

2000-01-01

This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation

Modeling Aspects of Activated Sludge Processes Part l l: Mathematical Process Modeling and Biokinetics of Activated Sludge Processes

Energy Technology Data Exchange (ETDEWEB)

AbdElHaleem, H S [Cairo Univ.-CivlI Eng. Dept., Giza (Egypt); EI-Ahwany, A H [CairoUlmrsity- Faculty ofEngincering - Chemical Engineering Department, Giza (Egypt); Ibrahim, H I [Helwan University- Faculty of Engineering - Biomedical Engineering Department, Helwan (Egypt); Ibrahim, G [Menofia University- Faculty of Engineering Sbebin EI Kom- Basic Eng. Sc. Dept., Menofia (Egypt)

2004-07-01

Mathematical process modeling and biokinetics of activated sludge process were reviewed considering different types of models. It has been evaluated the task group models of ASMI. and 2, and 3 versioned by Henze et al considering the conditions of each model and the different processes of which every model consists. It is revealed that ASMI contains some defects avoided in ASM3. Relied on homogeneity, Models can be classified into homogenous models characterized by taking the activated sludge process as one phase. In this type of models, the internal mass transfer inside the floes was neglected.. Hence, the kinetic parameter produces can be considered inaccurate. The other type of models is the heterogeneous model This type considers the mass transfer operations in addition to the biochemical reaction processes; hence, the resulted kinetic parameters can be considered more accurate than that of homogenous type.

Modeling Aspects of Activated Sludge Processes Part l l: Mathematical Process Modeling and Biokinetics of Activated Sludge Processes

International Nuclear Information System (INIS)

AbdElHaleem, H.S.; EI-Ahwany, A. H.; Ibrahim, H.I.; Ibrahim, G.

2004-01-01

Mathematical process modeling and biokinetics of activated sludge process were reviewed considering different types of models. It has been evaluated the task group models of ASMI. and 2, and 3 versioned by Henze et al considering the conditions of each model and the different processes of which every model consists. It is revealed that ASMI contains some defects avoided in ASM3. Relied on homogeneity, Models can be classified into homogenous models characterized by taking the activated sludge process as one phase. In this type of models, the internal mass transfer inside the floes was neglected.. Hence, the kinetic parameter produces can be considered inaccurate. The other type of models is the heterogeneous model This type considers the mass transfer operations in addition to the biochemical reaction processes; hence, the resulted kinetic parameters can be considered more accurate than that of homogenous type

Laboratory-scale in situ bioremediation in heterogeneous porous media: biokinetics-limited scenario.

Science.gov (United States)

Song, Xin; Hong, Eunyoung; Seagren, Eric A

2014-03-01

Subsurface heterogeneities influence interfacial mass-transfer processes and affect the application of in situ bioremediation by impacting the availability of substrates to the microorganisms. However, for difficult-to-degrade compounds, and/or cases with inhibitory biodegradation conditions, slow biokinetics may also limit the overall bioremediation rate, or be as limiting as mass-transfer processes. In this work, a quantitative framework based on a set of dimensionless coefficients was used to capture the effects of the competing interfacial and biokinetic processes and define the overall rate-limiting process. An integrated numerical modeling and experimental approach was used to evaluate application of the quantitative framework for a scenario in which slow-biokinetics limited the overall bioremediation rate of a polycyclic aromatic hydrocarbon (naphthalene). Numerical modeling was conducted to simulate the groundwater flow and naphthalene transport and verify the system parameters, which were used in the quantitative framework application. The experiments examined the movement and biodegradation of naphthalene in a saturated, heterogeneous intermediate-scale flow cell with two layers of contrasting hydraulic conductivities. These experiments were conducted in two phases: Phase I, simulating an inhibited slow biodegradation; and Phase II, simulating an engineered bioremediation, with system perturbations selected to enhance the slow biodegradation rate. In Phase II, two engineered perturbations to the system were selected to examine their ability to enhance in situ biodegradation. In the first perturbation, nitrogen and phosphorus in excess of the required stoichiometric amounts were spiked into the influent solution to mimic a common remedial action taken in the field. The results showed that this perturbation had a moderate positive impact, consistent with slow biokinetics being the overall rate-limiting process. However, the second perturbation, which was to

The biokinetic of incorporates radionuclides; Die Biokinetik von inkorporierten Radionukliden

Energy Technology Data Exchange (ETDEWEB)

Breustedt, Bastian [Karlsruher Institut fuer Technologie (KIT), Eggenstein-Leopoldshafen (Germany). Inst. fuer Strahlenforschung; Giussani, Augusto [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany). Arbeitsgruppe ' ' Externe und interne Dosimetrie, Biokinetik' '

2017-08-01

Incorporated radionuclides from nuclear accidents, fission product releases or nuclear medical administration are distributed in the human body in organs and tissue, absorbed 9or excreted. The interpretation of incorporation monitoring results and the estimation of the internal doses that cannot be measured directly need mathematical methods and the formulation of biokinetic models.

Cadmium bioavailability to Hyalella azteca from a periphyton diet compared to an artificial diet and application of a biokinetic model

Energy Technology Data Exchange (ETDEWEB)

Golding, Lisa A., E-mail: lisa.golding@csiro.au [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Borgmann, Uwe [Environment Canada, 867 Lakeshore Road, Burlington, Ontario L7R 4A6 (Canada); George Dixon, D. [Department of Biology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

2013-01-15

Differences between the bioavailability of cadmium in a periphyton diet and an artificial laboratory diet (TetraMin{sup Registered-Sign }) have important consequences for predicting bioaccumulation and toxicity in the freshwater amphipod Hyalella azteca. The assimilation efficiency (AE) of Cd was compared between periphyton and TetraMin{sup Registered-Sign} at low (1510 and 358 nmol/g ash-free dry mass respectively) and chronically lethal (31,200 and 2890 nmol/g ash-free dry mass respectively) Cd concentrations and in fresh and dry forms using a {sup 109}Cd radiotracer pulse-chase feeding technique. Assimilation efficiency of Cd from periphyton (AE = 3-14%) was lower than that for TetraMin{sup Registered-Sign} (AE = 44-86%) regardless of Cd concentration or food form. Ingestion rate (IR) was lower for dry than fresh forms of periphyton (0.042 and 0.16 g AFDM/g H. azteca/day respectively) and TetraMin{sup Registered-Sign} (0.19 and 0.87 AFDM/g H. azteca/day respectively) and depuration rate (k{sub e}) did not differ statistically with food type, form or Cd concentration (0.032-0.094 d{sup -1}). Biokinetic models with parameters of AE, IR and k{sub e} were used to estimate bioaccumulation from the separate food types. These estimates were compared to those from an independent chronic Cd saturation bioaccumulation model. While the model estimates did not concur, a sensitivity analysis indicated that AE and IR were the most influential biokinetic model parameters for Cd in periphyton and TetraMin{sup Registered-Sign} respectively. It was hypothesized that AE was underestimated for Cd in periphyton due to a non-adapted gut enzyme system and IR was overestimated for Cd in TetraMin{sup Registered-Sign} due to an initial rapid ingestion phase in H. azteca's feeding habits. This research demonstrated the importance of using ecologically relevant food types in laboratory experiments and verifying acute biokinetic model predictions of dietary metal contribution with

Bayesian model selection validates a biokinetic model for zirconium processing in humans

Science.gov (United States)

2012-01-01

Background In radiation protection, biokinetic models for zirconium processing are of crucial importance in dose estimation and further risk analysis for humans exposed to this radioactive substance. They provide limiting values of detrimental effects and build the basis for applications in internal dosimetry, the prediction for radioactive zirconium retention in various organs as well as retrospective dosimetry. Multi-compartmental models are the tool of choice for simulating the processing of zirconium. Although easily interpretable, determining the exact compartment structure and interaction mechanisms is generally daunting. In the context of observing the dynamics of multiple compartments, Bayesian methods provide efficient tools for model inference and selection. Results We are the first to apply a Markov chain Monte Carlo approach to compute Bayes factors for the evaluation of two competing models for zirconium processing in the human body after ingestion. Based on in vivo measurements of human plasma and urine levels we were able to show that a recently published model is superior to the standard model of the International Commission on Radiological Protection. The Bayes factors were estimated by means of the numerically stable thermodynamic integration in combination with a recently developed copula-based Metropolis-Hastings sampler. Conclusions In contrast to the standard model the novel model predicts lower accretion of zirconium in bones. This results in lower levels of noxious doses for exposed individuals. Moreover, the Bayesian approach allows for retrospective dose assessment, including credible intervals for the initially ingested zirconium, in a significantly more reliable fashion than previously possible. All methods presented here are readily applicable to many modeling tasks in systems biology. PMID:22863152

The Effect of Body Size in Mercury Accumulation Biokinetic of Cockle Shell (Anadara Granosa)

International Nuclear Information System (INIS)

Wahyu Retno Prihatiningsih

2007-01-01

Accumulation of mercury biokinetic in cockle shell (Anadara granosa) through water pathway has been investigated under laboratory condition. The objective of research is to find the effect of body size in mercury biokinetic of Anadara granosa and to find bioindicator based on biokinetic parameter. The research shows that body size of Anadara granosa give an effect to concentration factor and could barrier mercury contaminant. Concentration factor for size 1.9, 2.5 and 3.9 cm of biota moving high and reach steady state condition after 24 days. Concentration factor of Anadara granosa in size 1.9, 2.5 and 3.9 is 0.1476, 0.1645 and 0.2573 day. Based on mechanism of mercury biokinetic process, it was proof that Anadara granosa is an ideal invertebrate for bioindicator. (author)

Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Executive summary

International Nuclear Information System (INIS)

Jacob, P.; Paretzke, H.G.; Roth, P.

2000-01-01

The Association Contract covers a range of research domains that are important to the Radiation Protection Research Action, especially in the areas 'Evaluation of Radiation Risks' and 'Understanding Radiation Mechanisms and Epidemiology'. Three research projects concentrate on radiation dosimetry research and two projects on the modelling of radiation carcinogenesis. The following list gives an overview on the topics and responsible scientific project leaders of the Association Contract: Study of radiation fields and dosimetry at aviation altitudes. Biokinetics and dosimetry of incorporated radionuclides. Dose reconstruction. Biophysical models for the induction of cancer by radiation. Experimental data for the induction of cancer by radiation of different qualities. (orig.)

99mTc-UBI Biokinetics: A Specific Peptide for Infection Detection

Science.gov (United States)

Rodríguez-Cortés, J.; Meléndez-Alafort, L.; Herrera-Rodríguez, R.; Ferro-Flores, G.; Mitsoura, E.; Martínez-Duncker, C.

2003-09-01

Recently, antimicrobial peptides have been proposed as new agents to distinguish between bacterial infections and sterile inflammatory processes. Based on these considerations, Ubiquicidin peptide 29-41 (UBI) has been labeled with 99mTc using a new direct method showing a radiochemical purity > 97 %, high stability in human serum, and low protein binding. In addition 99mTc-UBI showed a specific in vitro and in vivo binding to bacteria. However its biokinetic parameters have not been evaluated since it is one of the new generation radiopharmaceuticals based on peptide structures. Therefore the aim of this project was to establish the biokinetic model for 99mTc-UBI. An activity from 74 to 148 MBq was injected to patients with bone infection and 5 whole body scans were taken at 1, 30, 120, 240 min and 24 h after radiopharmaceutical administration, with a dual head scanner. Urine was collected for 24 h. An antropomorphic phantom was previously used to calculate the effect of attenuation and scattered radiation on the gamma camera acquisition images. ROIs of the selected organs in patients (kidney, liver, heart, bone, soft tissue and lesion) were drawn, and attenuation and scatter corrected. The % urine elimination at 24 h and time integrated ROIs (cpm/pixel/ROIs) were used to obtain the residence time (τ) in each tissue and to establish the biokinetic model. Pharmacokinetic data show that blood clearance is biexponential with a mean residence time in the central compartment of 0.52 h. The images showed non-accumulation in metabolic organs. More than 75 % of the injected activity was eliminated by renal clearance 4 h after 99mTc-UBI administration. The mean radiation dose calculated according to the MIRD formalism was 0.130 mGy/MBq for kidney and the effective dose was 4.29 × 10-3 mSv/MBq.

Quantitative biokinetic analysis of radioactively labelled, inhaled Titanium dioxide Nanoparticles in a rat model

International Nuclear Information System (INIS)

Kreyling, Wolfgang G.; Wenk, Alexander; Semmler-Behnke, Manuela

2010-01-01

The aim of this project was the determination of the biokinetics of TiO 2 nanoparticles (NP) in the whole body of healthy adult rats after NP administration to the respiratory tract - either via inhalation or instillation. We developed an own methodology to freshly synthesize and aerosolize TiO 2 -NP in our lab for the use of inhalation studies. These NP underwent a detailed physical and chemical characterization providing pure polycrystalline anatase TiO 2 -NP of about 20 nm (geometric standard deviation 1.6) and a specific surface area of 270 m 2 /g. In addition, we developed techniques for sufficiently stable radioactive 48 V labelling of the TiO 2 NP. The kinetics of solubility of 48 V was thoroughly determined. The methodology of quantitative biokinetics allows for a quantitative balance of the retained and excreted NP in control of the administered NP dose and provides a much more precise determination of NP fractions and concentrations of NP in organs and tissues of interest as compared to spotting biokinetics studies. Small fractions of TiO 2 -NP translocate across the air-blood-barrier and accumulate in secondary target organs, soft tissue and skeleton. The amount of translocated TiO 2 -NP is approximately 2% of TiO 2 -NP deposited in the lungs. A prominent fraction of these translocated TiO 2 -NP was found in the remainder. Smaller amounts of TiO 2 -NP accumulate in secondary organs following particular kinetics. TiO 2 -NP translocation was grossly accomplished within the first 2-4 hours after inhalation followed by retention in all organs and tissues studied without any detectable clearance of these biopersistent TiO 2 -NP within 28 days. Therefore, our data suggest crossing of the air-blood-barrier of the lungs and subsequent accumulation in secondary organs and tissues depends on the NP material and its physico-chemical properties. Furthermore, we extrapolate that during repeated or chronic exposure to insoluble NP the translocated fraction of NP will

Quantitative biokinetic analysis of radioactively labelled, inhaled Titanium dioxide Nanoparticles in a rat model

Energy Technology Data Exchange (ETDEWEB)

Kreyling, Wolfgang G.; Wenk, Alexander; Semmler-Behnke, Manuela [Helmholtz Zentrum Muenchen, Deutsches Forschungszentrum fuer Gesundheit und Umwelt GmbH (Germany). Inst. fuer Lungenbiologie und Erkrankungen, Netzwerk Nanopartikel und Gesundheit

2010-09-15

The aim of this project was the determination of the biokinetics of TiO{sub 2} nanoparticles (NP) in the whole body of healthy adult rats after NP administration to the respiratory tract - either via inhalation or instillation. We developed an own methodology to freshly synthesize and aerosolize TiO{sub 2}-NP in our lab for the use of inhalation studies. These NP underwent a detailed physical and chemical characterization providing pure polycrystalline anatase TiO{sub 2}-NP of about 20 nm (geometric standard deviation 1.6) and a specific surface area of 270 m{sup 2}/g. In addition, we developed techniques for sufficiently stable radioactive {sup 48}V labelling of the TiO{sub 2} NP. The kinetics of solubility of {sup 48}V was thoroughly determined. The methodology of quantitative biokinetics allows for a quantitative balance of the retained and excreted NP in control of the administered NP dose and provides a much more precise determination of NP fractions and concentrations of NP in organs and tissues of interest as compared to spotting biokinetics studies. Small fractions of TiO{sub 2}-NP translocate across the air-blood-barrier and accumulate in secondary target organs, soft tissue and skeleton. The amount of translocated TiO{sub 2}-NP is approximately 2% of TiO{sub 2}-NP deposited in the lungs. A prominent fraction of these translocated TiO{sub 2}-NP was found in the remainder. Smaller amounts of TiO{sub 2}-NP accumulate in secondary organs following particular kinetics. TiO{sub 2}-NP translocation was grossly accomplished within the first 2-4 hours after inhalation followed by retention in all organs and tissues studied without any detectable clearance of these biopersistent TiO{sub 2}-NP within 28 days. Therefore, our data suggest crossing of the air-blood-barrier of the lungs and subsequent accumulation in secondary organs and tissues depends on the NP material and its physico-chemical properties. Furthermore, we extrapolate that during repeated or chronic

Mathematical solutions to problems in radiological protection involving air sampling and biokinetic modelling

International Nuclear Information System (INIS)

Birchall, A.

1989-04-01

Intakes of radionuclides are estimated with the personal air sampler (PAS) and by biological monitoring techniques: in the case of plutonium, there are problems with both methods. The statistical variation in activity collected when sampling radioactive aerosols with low number concentrations was investigated. It was shown that the PAS is barely adequate for monitoring plutonium at annual limit of intake (ALI) levels in typical workplace conditions. Two algorithms were developed, enabling non-recycling and recycling compartmental models to be solved. Their accuracy and speed were investigated, and methods of dealing with partitioning, continuous intake, and radioactive progeny were discussed. Analytical, rather than numerical, methods were used. These are faster, and thus ideally suited for implementation on microcomputers. The algorithms enable non-specialists to solve quickly and easily any first order compartmental model, including all the ICRP metabolic models. Non-recycling models with up to 50 compartments can be solved in seconds: recycling models take a little longer. A biokinetic model for plutonium in man following systemic uptake was developed. The proposed ICRP lung model (1989) was represented by a first order compartmental model. These two models were combined, and the recycling algorithm was used to calculate urinary and faecal excretion of plutonium following acute or chronic intake by inhalation. The results indicate much lower urinary excretion than predicted by ICRP Publication 54. (author)

An empirical multivariate log-normal distribution representing uncertainty of biokinetic parameters for 137Cs

International Nuclear Information System (INIS)

Miller, G.; Martz, H.; Bertelli, L.; Melo, D.

2008-01-01

A simplified biokinetic model for 137 Cs has six parameters representing transfer of material to and from various compartments. Using a Bayesian analysis, the joint probability distribution of these six parameters is determined empirically for two cases with quite a lot of bioassay data. The distribution is found to be a multivariate log-normal. Correlations between different parameters are obtained. The method utilises a fairly large number of pre-determined forward biokinetic calculations, whose results are stored in interpolation tables. Four different methods to sample the multidimensional parameter space with a limited number of samples are investigated: random, stratified, Latin Hypercube sampling with a uniform distribution of parameters and importance sampling using a lognormal distribution that approximates the posterior distribution. The importance sampling method gives much smaller sampling uncertainty. No sampling method-dependent differences are perceptible for the uniform distribution methods. (authors)

Biokinetics and dosimetric studies about 99mTc(V)DMSA distribution

International Nuclear Information System (INIS)

Correia, M.B.L.; Magnata, S.S.L.P.; Silva, I.M.S.; Lima, F.F.; Catanho, M.T.J.A.

2008-01-01

Research for radiodiagnostic agents should considerate biological critical parameters as half-life effective, target/not target uptake ratio and metabolites that together will determinate the biokinetic. Each parameter give own contribution in the absorbed dose. The dimercaptosuccinic acid (DMSA) labeled with 99m Tc(VN) is a radiopharmaceutical which has well established role in medullar thyroid carcinoma and has been proposed in complementary evaluation of bone metastasis. The aim of this work was study the biokinetics and dosimetry of 99m Tc(V)-DMSA by animal model. The 99m Tc(V)-DMSA was prepared by (III)DMSA kit alkalized. The methodology used mice, 70 days old, both males and females. The animals (n=5) received 99m Tc(V)DMSA administered IV (tail vein). After determinate times (30 min, 1h, 5h and 12h) the animals were sacrificed, the organs (blood, lungs, kidneys, muscle and bone) were excised and the activities were measured by a gamma counter. The results were evaluated based on %activity/g and the absorbed dose was estimated by extrapolation of data from animal to human, using the residence time to each organ in the MIRDOSE 3.0 program. The results show that the majority of organs reaches the top uptake at 30 min, the kidney has the greatest uptake in this time, (4.81 ± 1.38) % activity per gram, while the bone presents its highest uptake at 1h (5.49 ± 0.47)% activity per gram, after 1h all the organs had activity exponential decrease. About the absorbed dose estimated to human scale, the preliminary results showed higher value to bone, being the soft tissue dose relatively low. These dose values, however, are submitted to biological implications which are under studying yet. The biokinetic profile of 99m Tc(V)-DMSA, prepared from a DMSA kit by IPEN, was well established, allowing quantifying of residence time, while the dosimetric model presented preliminary data which directs to new analyzes

Biokinetics of radiolabeled Iodophenylpentadecanoic acid (I-123-IPPA) and thallium-201 in a rabbit model of chronic myocardial infarction measured using a series of thermoluminescent dosimeters

Science.gov (United States)

Medich, David Christopher

1997-09-01

The biokinetics of Iodophenylpentadecanoic acid (123I-IPPA) during a chronic period of myocardial infarction were determined and compared to 201Tl. IPPA was assessed as a perfusion and metabolic tracer in the scintigraphic diagnosis of coronary artery disease. The myocardial clearance kinetics were measured by placing a series of thermoluminescent dosimeters (TLDs) on normal and infarcted tissue to measure the local myocardial activity content over time. The arterial blood pool activity was fit to a bi-exponential function for 201Tl and a tri-exponential function for 123I-IPPA to estimate the left ventricle contribution to TLD response. At equilibrium, the blood pool contribution was estimated experimentally to be less than 5% of the total TLD response. The method was unable to resolve the initial uptake of the imaging agent due in part to the 2 minute TLD response integration time and in part to the 30 second lag time for the first TLD placement. A noticeable disparity was observed between the tracer concentrations of IPPA in normal and ischemic tissue of approximately 2:1. The fitting parameters (representing the biokinetic eigenvalue rate constants) were related to the fundamental rate constants of a recycling biokinetic model. The myocardial IPPA content within normal tissue was elevated after approximately 130 minutes post injection. This phenomenon was observed in all but one (950215) of the IPPA TLD kinetics curves.

Biokinetic study of 131I following ablation dose administration

International Nuclear Information System (INIS)

Nascimento, A.C.H.; Lipsztein, J.L.; Lucena, E.A.; Dantas, B.M.; Rebelo, A.M.O.; Mello, R.C.

2002-01-01

Aim: The aim of this investigation is to study biokinetics from internally 131 I deposited for thyroid cancer patients during radioiodine therapy (2 to 3 days), after ablation dose administration (3.7 GBq). These data will help in the elaboration of a metabolic model, which will permit absorbed dose assessment for this specific case, since the biokinetic models for iodine available in scientific literature can not be applied to thyroidectomized patient's studies. Material and Methods: Four females patients, between 22 and 50 years old, without metastases, between 1.9 to 6% of remnant thyroid tissue uptake, agreed to contribute to this study. For the in vivo bioassay, periodical measurements were performed along internment time (2 to 3 days), just after Na 131 I dose administration (3.7 GBq). For this, we used the counting system for Nuclear Medicine model 13S002, IEN/CNEN- Brazil, which was adapted with lead filters, in order to allow the work with high rate counting. The measurements were performed in two geometries: thyroid region and thigh. Results: For each patient, we have done approximately 26 measurements for both geometries, starting at the first hour following dose administration until the release from hospital of patient. The results of counting rate (cps) were plotted against time (h). The measurements suggest a relation between remnant thyroid tissue uptake values and the time where counting rates start decreasing. In addition, it was observed a correlation between remnant thyroid tissue radioactive burdens and the circulating iodine through time. Conclusion: It is necessary to follow-up a greater number of patients aiming to confirm the observed correlations and with a greater number of measurements during the first 24 hours, in other to delimit the time range of increasing and decreasing counting rate

Performance analysis of numeric solutions applied to biokinetics of radionuclides

International Nuclear Information System (INIS)

Mingatos, Danielle dos Santos; Bevilacqua, Joyce da Silva

2013-01-01

Biokinetics models for radionuclides applied to dosimetry problems are constantly reviewed by ICRP. The radionuclide trajectory could be represented by compartmental models, assuming constant transfer rates between compartments. A better understanding of physiological or biochemical phenomena, improve the comprehension of radionuclide behavior in the human body and, in general, more complex compartmental models are proposed, increasing the difficulty of obtaining the analytical solution for the system of first order differential equations. Even with constant transfer rates numerical solutions must be carefully implemented because of almost singular characteristic of the matrix of coefficients. In this work we compare numerical methods with different strategies for ICRP-78 models for Thorium-228 and Uranium-234. The impact of uncertainty in the parameters of the equations is also estimated for local and global truncation errors. (author)

Study of the influence of radionuclide biokinetics on in vivo counting using voxel phantoms

International Nuclear Information System (INIS)

Lamart, St.

2008-10-01

The in vivo measurement is an efficient method to estimate the retention of activity in case of internal contamination. However, it is currently limited by the use of physical phantoms for the calibration, not enabling to reproduce neither the morphology of the measured person nor the actual distribution of the contamination. The current method of calibration therefore leads to significant systematic uncertainties on the quantification of the contamination. To improve the in vivo measurement, the Laboratory of Internal Dose Assessment (LEDI, IRSN) has developed an original numerical calibration method with the OEDIPE software. It is based on voxel phantoms created from the medical images of persons, and associated with the MCNPX Monte Carlo code of particle transport. The first version of this software enabled to model simple homogeneous sources and to better estimate the systematic uncertainties in the lung counting of actinides due to the detector position and to the heterogeneous distribution of activity inside the lungs. However, it was not possible to take into account the dynamic feature, and often heterogeneous distribution between body organs and tissues of the activity. Still, the efficiency of the detection system depends on the distribution of the source of activity. The main purpose of the thesis work is to answer to the question: what is the influence of the biokinetics of the radionuclides on the in vivo counting? To answer it, it was necessary to deeply modify OEDIPE. This new development enabled to model the source of activity more realistically from the reference biokinetic models defined by the ICRP. The first part of the work consisted in developing the numerical tools needed to integrate the biokinetics in OEDIPE. Then, a methodology was developed to quantify its influence on the in vivo counting from the results of simulations. This method was carried out and validated on the model of the in vivo counting system of the LEDI. Finally, the

The computation of ICRP dose coefficients for intakes of radionuclides with PLEIADES: biokinetic aspects.

Science.gov (United States)

Fell, T P

2007-01-01

The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts--the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES.

The computation of ICRP dose coefficients for intakes of radionuclides with PLEIADES: biokinetic aspects

International Nuclear Information System (INIS)

Fell, T.P.

2007-01-01

The ICRP has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public including children and pregnant or lactating women. The calculation of these coefficients conveniently divides into two distinct parts - the biokinetic and dosimetric. This paper gives a brief summary of the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. (author)

Biokinetics and bacterial communities of propionate oxidizing bacteria in phased anaerobic sludge digestion systems.

Science.gov (United States)

Zamanzadeh, Mirzaman; Parker, Wayne J; Verastegui, Yris; Neufeld, Josh D

2013-03-15

Phased anaerobic digestion is a promising technology and may be a potential source of bio-energy production. Anaerobic digesters are widely used for sewage sludge stabilization and thus a better understanding of the microbial process and kinetics may allow increased volatile solids reduction and methane production through robust process operation. In this study, we analyzed the impact of phase separation and operational conditions on the bio-kinetic characteristics and communities of bacteria associated with four phased anaerobic digestion systems. In addition to significant differences between bacterial communities associated with different digester operating temperatures, our results also revealed that bacterial communities in the phased anaerobic digestion systems differed between the 1st and 2nd phase digesters and we identified strong community composition correlations with several measured physicochemical parameters. The maximum specific growth rates of propionate oxidizing bacteria (POB) in the mesophilic and thermophilic 1st phases were 11 and 23.7 mgCOD mgCOD(-1) d(-1), respectively, while those of the mesophilic and thermophilic 2nd-phase digesters were 6.7 and 18.6 mgCOD mgCOD(-1) d(-1), respectively. Hence, the biokinetic characteristics of the POB population were dependent on the digester loading. In addition, we observed that the temperature dependency factor (θ) values were higher for the less heavily loaded digesters as compared to the values obtained for the 1st-phase digesters. Our results suggested the appropriate application of two sets of POB bio-kinetic that reflect the differing growth responses as a function of propionate concentration (and/or organic loading rates). Also, modeling acetogenesis in phased anaerobic sludge digestion systems will be improved considering a population shift in separate phases. On the basis of the bio-kinetic values estimated in various digesters, high levels of propionate in the thermophilic digesters may be

Biokinetics aand dosimetry of inhaled 238PuO2 in the beagle dog: An update

International Nuclear Information System (INIS)

Guilmette, R.A.; Griffith, W.C.; Diel, J.H.

1994-01-01

The temporal and spatial distributions of 238 Pu have been measured during the course of a dose-response study of the biological effects of inhaled 238 PuO 2 in Beagle dogs. These measurements were done on the dose-response study animals, as well as a separate group of dogs exposed to similar aerosols and killed serially out to 4 y after exposure. The data from this latter group provided the basis for the development of a biokinetic/dosimetric model for 238 PuO 2 in dogs. Since the publication of this model, several important findings have been made that affected the dosimetric evaluations. The first involved the discovery of significant quantities of natural uranium (U) in the feces samples. The U was measured with the plutonium (Pu), which inflated the values for purported Pu in feces. The second finding involved the addition of Pu biokinetics data from the dose-response dogs, which increased the period of observation from 4 y to 15 y; these later data were not consistent with the earlier model predictions. The purpose of this investigation was (1) to remove the analytical bias in the 238 Pu radiochemical data due to the U and (2) to modify the original model of Mewhinney and Diel, taking into account all data from both studies

Biokinetics – the development of a health profession from physical ...

African Journals Online (AJOL)

Biokinetics – the development of a health profession from physical education - a historical perspective. ... In this respect some medical aid funds supported this philosophy of health promotion, as the curative treatment of health problems are becoming increasingly expensive and are burdening health-care costs. At present ...

Quantitative analysis of multiple biokinetic models using a dynamic water phantom: A feasibility study

Science.gov (United States)

Chiang, Fu-Tsai; Li, Pei-Jung; Chung, Shih-Ping; Pan, Lung-Fa; Pan, Lung-Kwang

2016-01-01

ABSTRACT This study analyzed multiple biokinetic models using a dynamic water phantom. The phantom was custom-made with acrylic materials to model metabolic mechanisms in the human body. It had 4 spherical chambers of different sizes, connected by 8 ditches to form a complex and adjustable water loop. One infusion and drain pole connected the chambers to an auxiliary silicon-based hose, respectively. The radio-active compound solution (TC-99m-MDP labeled) formed a sealed and static water loop inside the phantom. As clean feed water was infused to replace the original solution, the system mimicked metabolic mechanisms for data acquisition. Five cases with different water loop settings were tested and analyzed, with case settings changed by controlling valve poles located in the ditches. The phantom could also be changed from model A to model B by transferring its vertical configuration. The phantom was surveyed with a clinical gamma camera to determine the time-dependent intensity of every chamber. The recorded counts per pixel in each chamber were analyzed and normalized to compare with theoretical estimations from the MATLAB program. Every preset case was represented by uniquely defined, time-dependent, simultaneous differential equations, and a corresponding MATLAB program optimized the solutions by comparing theoretical calculations and practical measurements. A dimensionless agreement (AT) index was recommended to evaluate the comparison in each case. ATs varied from 5.6 to 48.7 over the 5 cases, indicating that this work presented an acceptable feasibility study. PMID:27286096

Human health risk assessment of lead from mining activities at semi-arid locations in the context of total lead exposure.

Science.gov (United States)

Zheng, Jiajia; Huynh, Trang; Gasparon, Massimo; Ng, Jack; Noller, Barry

2013-12-01

Lead from historical mining and mineral processing activities may pose potential human health risks if materials with high concentrations of bioavailable lead minerals are released to the environment. Since the Joint Expert Committee on Food Additives of Food and Agriculture Organization/World Health Organization withdrew the Provisional Tolerable Weekly Intake of lead in 2011, an alternative method was required for lead exposure assessment. This study evaluated the potential lead hazard to young children (0-7 years) from a historical mining location at a semi-arid area using the U.S. EPA Integrated Exposure Uptake Biokinetic (IEUBK) Model, with selected site-specific input data. This study assessed lead exposure via the inhalation pathway for children living in a location affected by lead mining activities and with specific reference to semi-arid conditions and made comparison with the ingestion pathway by using the physiologically based extraction test for gastro-intestinal simulation. Sensitivity analysis for major IEUBK input parameters was conducted. Three groups of input parameters were classified according to the results of predicted blood concentrations. The modelled lead absorption attributed to the inhalation route was lower than 2 % (mean ± SE, 0.9 % ± 0.1 %) of all lead intake routes and was demonstrated as a less significant exposure pathway to children's blood, compared with ingestion. Whilst dermal exposure was negligible, diet and ingestion of soil and dust were the dominant parameters in terms of children's blood lead prediction. The exposure assessment identified the changing role of dietary intake when house lead loadings varied. Recommendations were also made to conduct comprehensive site-specific human health risk assessment in future studies of lead exposure under a semi-arid climate.

Transuranic biokinetic parameters for marine invertebrates--a review.

Science.gov (United States)

Ryan, T P

2002-04-01

A catalogue of biokinetic parameters for the transuranic elements plutonium, americium, curium, neptunium, and californium in marine invertebrates is presented. The parameters considered are: the seawater-animal concentration factor (CF); the sediment-animal concentration ratio (CR); transuranic assimilation efficiency; transuranic tissue distribution and transuranic elimination rates. With respect to the seawater-animal CF, authors differ considerably on how they define this parameter and a seven-point reporting system is suggested. Transuranic uptake from sediment by animals is characterised by low CRs. The assimilation efficiencies of transuranic elements in marine invertebrates are high compared to vertebrates and mammals in general and the distribution of transuranics within the body tissue of an animal is dependent on the uptake path. The elimination of transuranics from most species examined conformed to a standard biphasic exponential model though some examples with three elimination phases were identified.

Children's Lead Exposure: A Multimedia Modeling Analysis to Guide Public Health Decision-Making.

Science.gov (United States)

Zartarian, Valerie; Xue, Jianping; Tornero-Velez, Rogelio; Brown, James

2017-09-12

Drinking water and other sources for lead are the subject of public health concerns around the Flint, Michigan, drinking water and East Chicago, Indiana, lead in soil crises. In 2015, the U.S. Environmental Protection Agency (EPA)'s National Drinking Water Advisory Council (NDWAC) recommended establishment of a "health-based, household action level" for lead in drinking water based on children's exposure. The primary objective was to develop a coupled exposure-dose modeling approach that can be used to determine what drinking water lead concentrations keep children's blood lead levels (BLLs) below specified values, considering exposures from water, soil, dust, food, and air. Related objectives were to evaluate the coupled model estimates using real-world blood lead data, to quantify relative contributions by the various media, and to identify key model inputs. A modeling approach using the EPA's Stochastic Human Exposure and Dose Simulation (SHEDS)-Multimedia and Integrated Exposure Uptake and Biokinetic (IEUBK) models was developed using available data. This analysis for the U.S. population of young children probabilistically simulated multimedia exposures and estimated relative contributions of media to BLLs across all population percentiles for several age groups. Modeled BLLs compared well with nationally representative BLLs (0-23% relative error). Analyses revealed relative importance of soil and dust ingestion exposure pathways and associated Pb intake rates; water ingestion was also a main pathway, especially for infants. This methodology advances scientific understanding of the relationship between lead concentrations in drinking water and BLLs in children. It can guide national health-based benchmarks for lead and related community public health decisions. https://doi.org/10.1289/EHP1605.

Comparison between two clones of Daphnia magna: Effects of multigenerational cadmium exposure on toxicity, individual fitness, and biokinetics

International Nuclear Information System (INIS)

Guan Rui; Wang Wenxiong

2006-01-01

We investigated the effects of genotype (two different clones) and multigenerational Cd-exposure history on Cd toxicity, individual fitness, and biokinetics in populations of a freshwater cladoceran Daphnia magna. The adults of the tolerant (T) clone had longer mean-survival-time than the sensitive (S) clone in both control groups (without Cd-exposure) and continuous Cd-exposure groups, but the two clones showed comparable resistances to acute Cd stress in the recovery groups. The body concentration of metallothionein (MT) played a critical role in handling Cd stress, which mainly accounted for the significant difference between the two clones in terms of survival distribution. High comparability of these two clones in individual fitness parameters and biokinetics suggested that these parameters are unlikely driven by genetic variation. For each specific clone, continuous Cd-exposure inhibited the animal growth, elevated the MT induction, and increased the Cd uptake rate (ingestion rate, assimilation efficiency from dietary phase, and uptake rate from dissolved phase), all of which enhanced the weight-specific Cd accumulation in daphnids' bodies. The strong dependence of biokinetic parameters on environmental factors (e.g., food concentrations, pH, dissolved or dietary metal concentration, and metal exposure histories) rather than on genotypes implied the great potential of using biokinetics in inter-lab comparisons and environmental risk assessments

Comparison between two clones of Daphnia magna: effects of multigenerational cadmium exposure on toxicity, individual fitness, and biokinetics.

Science.gov (United States)

Guan, Rui; Wang, Wen-Xiong

2006-03-10

We investigated the effects of genotype (two different clones) and multigenerational Cd-exposure history on Cd toxicity, individual fitness, and biokinetics in populations of a freshwater cladoceran Daphnia magna. The adults of the tolerant (T) clone had longer mean-survival-time than the sensitive (S) clone in both control groups (without Cd-exposure) and continuous Cd-exposure groups, but the two clones showed comparable resistances to acute Cd stress in the recovery groups. The body concentration of metallothionein (MT) played a critical role in handling Cd stress, which mainly accounted for the significant difference between the two clones in terms of survival distribution. High comparability of these two clones in individual fitness parameters and biokinetics suggested that these parameters are unlikely driven by genetic variation. For each specific clone, continuous Cd-exposure inhibited the animal growth, elevated the MT induction, and increased the Cd uptake rate (ingestion rate, assimilation efficiency from dietary phase, and uptake rate from dissolved phase), all of which enhanced the weight-specific Cd accumulation in daphnids' bodies. The strong dependence of biokinetic parameters on environmental factors (e.g., food concentrations, pH, dissolved or dietary metal concentration, and metal exposure histories) rather than on genotypes implied the great potential of using biokinetics in inter-lab comparisons and environmental risk assessments.

A profile of Biokinetics service provided by the University of Kwa ...

African Journals Online (AJOL)

Biokinetics can be viewed as an emerging member of the South African health professions in comparison to the longstanding professions of physiotherapy, chiropractics and occupational therapy which were established in 1924, 1939 and 1945, respectively. The aim of this investigation was to determine the profile of the ...

Uranium: biokinetics and toxicity; Biocinetique et toxicite de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Menetrier, F.; Renaud-Salis, V.; Flury-Herard, A

2000-07-01

This report was achieved as a part of a collaboration with the Fuel Cycle Direction. Its aim was to give the state of the art about: the behaviour of uranium in the human organism (biokinetics) after ingestion, its toxicity (mainly renal) and the current regulation about its incorporation. Both in the upstream and in the downstream of the fuel cycle, uranium remains, quantitatively, the first element in the cycle which is, at the present time, temporarily disposed or recycled. Such a considerable quantity of uranium sets the problem of its risk on the health. In the long term, the biosphere may be affected and consequently the public may ingest water or food contaminated with uranium. In this way, radiological and chemical toxicity risk may be activated. This report emphasizes: the necessity of confirming some experimental and epidemiological biokinetic data used or not in the ICRP models. Unsolved questions remain about the gastrointestinal absorption according to chemical form (valency state, mixtures...), mass and individual variations (age, disease) further a chronic ingestion of uranium. It is well established that uranium is mainly deposited in the skeleton and the kidney. But the skeleton kinetics following a chronic ingestion and especially in some diseases has to be more elucidated; the necessity of taking into account uranium at first as a chemical toxic, essentially in the kidney and determining the threshold of functional lesion. In this way, it is important to look for some specific markers; the problem of not considering chemical toxicity of uranium in the texts regulating its incorporation.

Biokinetics and dosimetry of radioactively labelled organic C-14 compounds

International Nuclear Information System (INIS)

Krins, A.; Sahre, P.; Schoenmuth, T.

2003-12-01

The report starts with summarising research work and the resulting scientific information in connection with the dosimetry of C-14 labelled organic compounds. Biokinetic models are developed for compounds such as benzene, phenol, aniline, nitrobenzene, and a selection of pharmaceuticals, in order to show the radioactivity distribution after administration of the C-14 labelled substances. Based on the those models, dose coefficients and excretion rates are derived. The following synoptic view of the available data library leads on to a discussion of various aspects, as eg. the question of whether and how monitoring for detection of incorporation of C-14 administered with labelled organic compounds is possible. None of the questions and aspects arising in connection with this subject can be adequately dealt with in the present document, but concepts and methods are presented which permit an interpretation of radioactivity excretion data measured after incorporation of C-14 labelled organic substances. (orig./CB) [de

Mechanism of cisplatin proximal tubule toxicity revealed by integrating transcriptomics, proteomics, metabolomics and biokinetics.

Science.gov (United States)

Wilmes, Anja; Bielow, Chris; Ranninger, Christina; Bellwon, Patricia; Aschauer, Lydia; Limonciel, Alice; Chassaigne, Hubert; Kristl, Theresa; Aiche, Stephan; Huber, Christian G; Guillou, Claude; Hewitt, Philipp; Leonard, Martin O; Dekant, Wolfgang; Bois, Frederic; Jennings, Paul

2015-12-25

Cisplatin is one of the most widely used chemotherapeutic agents for the treatment of solid tumours. The major dose-limiting factor is nephrotoxicity, in particular in the proximal tubule. Here, we use an integrated omics approach, including transcriptomics, proteomics and metabolomics coupled to biokinetics to identify cell stress response pathways induced by cisplatin. The human renal proximal tubular cell line RPTEC/TERT1 was treated with sub-cytotoxic concentrations of cisplatin (0.5 and 2 μM) in a daily repeat dose treating regime for up to 14 days. Biokinetic analysis showed that cisplatin was taken up from the basolateral compartment, transported to the apical compartment, and accumulated in cells over time. This is in line with basolateral uptake of cisplatin via organic cation transporter 2 and bioactivation via gamma-glutamyl transpeptidase located on the apical side of proximal tubular cells. Cisplatin affected several pathways including, p53 signalling, Nrf2 mediated oxidative stress response, mitochondrial processes, mTOR and AMPK signalling. In addition, we identified novel pathways changed by cisplatin, including eIF2 signalling, actin nucleation via the ARP/WASP complex and regulation of cell polarization. In conclusion, using an integrated omic approach together with biokinetics we have identified both novel and established mechanisms of cisplatin toxicity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biokinetics and dosimetry with 177Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

Science.gov (United States)

Rodríguez-Cortés, J.; de Murphy, C. Arteaga; Ferro-Flores, Ge; Pedraza-López, M.; Murphy-Stack, E.

Malignant pancreatic tumours induced in athymic mice are a good model for peptide receptor targeted radiotherapy. The objective of this research was to determine biokinetic parameters in mice, in order to estimate the induced pancreatic tumour absorbed doses and to evaluate an `in house' 177Lu-DOTA-TATE radiopharmaceutical as part of preclinical studies for targeted therapy in humans. AR42J murine pancreas cancer cells expressing somatostatin receptors, were implanted in athymic mice (nD22) to obtain biokinetic and dosimetric data of 177Lu-DOTA-TATE. The mean tumour uptake 2 h post injection was 14.76±1.9% I.A./g; kidney and pancreas uptake, at the same time, were 7.27±1.1% I.A./g (1.71±0.90%/organ) and 4.20±0.98% I.A./g (0.42±0.03%/organ), respectively. The mean absorbed dose to tumour, kidney and pancreas was 0.58±0.02 Gy/MBq; 0.23±0.01 Gy/MBq and 0.14±0.01 Gy/MBq, respectively. These studies justify further dosimetric estimations to ensure that 177Lu-DOTA-TATE will act as expected in humans.

A biokinetic study of {sup 209}Po in man

Energy Technology Data Exchange (ETDEWEB)

Henricsson, C.F.; Ranebo, Y. [Department of Medical Radiation Physics, Clinical Sciences in Lund, Lund University, Skane University Hospital in Lund (Sweden); Hansson, M. [Medical Radiation Physics, Department of Clinical Sciences in Malmoe, Lund University, Skane University Hospital in Malmoe (Sweden); Raeaef, C.L., E-mail: Christopher.Raaf@med.lu.se [Medical Radiation Physics, Department of Clinical Sciences in Malmoe, Lund University, Skane University Hospital in Malmoe (Sweden); Holm, E. [Norwegian Radiation Protection Authority, Osteras (Norway)

2012-10-15

Five adult volunteers participated in a biokinetic study of radioactive polonium. Portions of about 10 Bq of {sup 209}Po were orally administrated to four of the volunteers in a single ingestion. The fifth volunteer ingested a daily amount of 53 mBq of 209Po for 243 d to study the time to achieve equilibrium between intake and excretion for protracted intakes. For the subjects ingesting single intakes of {sup 209}Po complete sampling of urine and feces was subsequently collected the first few days upon the ingestion. The samples were processed with radiochemical extraction and analyzed with alpha spectrometry. In the study, the maximum daily excretion rates in feces were 18-50% of the ingested activity, observed within 3 d after intake. Regarding the urine excretion, the daily excretion peaked, on average, at 0.15-1% of the ingested activity within two days upon intake. These results indicate an average gastro-intestinal uptake fraction of 0.46 {+-} 0.08, which agrees well with earlier biokinetic studies of polonium in man. -- Highlights: Black-Right-Pointing-Pointer Human metabolism of an oral intake of polonium. Black-Right-Pointing-Pointer 4 individuals were administrated about 10 Bq polonium-209. Black-Right-Pointing-Pointer Gastro-intestinal uptake fraction, if orally administrated polonium-209 was investigated. Black-Right-Pointing-Pointer The biological half-time of polonium in human body was studied.

Biokinetic behavior of Tc in the red abalone, Haliotis rufescens: a reassessment

International Nuclear Information System (INIS)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

1981-01-01

The biokinetic behavior of /sup 95m/Tc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments on other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalone exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics cannot be described by a single compartment model as had been previously advanced. Assimilation of /sup 95m/Tc by the abalone following a single feeding of labeled macroalga, Nereocystis pyrifera, is high (approx. 45%) and loss kinetics are similar to those observed following direct uptake from seawater

Accuracy of internal dose calculations with special consideration of radiopharmaceutical biokinetics

International Nuclear Information System (INIS)

Roedler, H.D.

1981-01-01

The individual steps of internal dose calculation, including the models and data used, as well as error considerations, are analysed following a short synopsis on the formalism of absorbed dose calculation. The mean dose in a target tissue depends on the administered activity, the residence time of the activity in the source tissues and the mean absorbed dose in the target tissue per transformation in a source tissue. Usually, a standard dosage is applied in radionuclide studies except in children. Actually administered and nomial activities generally differ by less than 10%. For the purpose of internal dose calculation, the biokinetics of a radiopharmaceutical are reflected in the residence times for the individual source tissues. The methods and the evaluation of measurements of biodistribution and retention data are discussed. The extrapolation of animal data to man is treated in some detail, including a survey of the methods used, as well as an attempt for validating these methods. None of these seem to yield more convincing results than the direct transfer of the residence times from animal to man, at least for the two radiopharmaceuticals discussed. The minimum period of measurement to derive residence times for the purpose of dose calculation has been determined as about one physical half-time. Some problems of the dose per transformation to a phantom are presented, including the age- or size-dependence of the internal dose. Organ doses to the phantom, calculated from different apparently reliable sets of biokinetic data, are generally compatible within a factor of 2 to 3, and somatically effective doses are generally compatible within a factor of less than 2

Acquisition of biokinetic data for internal dose calculations for some novel radiopharmaceuticals

International Nuclear Information System (INIS)

Smith, T.; Zanelli, G.D.; Crawley, C.W.

1986-01-01

Estimation of radiation dose commitment, expresses as an effective dose equivalent, is a prior requisite to the application for a license to administer radiopharmaceuticals and, therefore, in the case of novel radiopharmaceuticals is leading to an increasing awareness of the need for dosimetry-orientated studies. In this laboratory potential new radiopharmaceuticals are investigated initially by animal studies to assess the possible distribution in man, and subsequently in controlled volunteer studies designed to obtain the maximum possible amount of biokinetic data to allow accurate estimation of radiation dose. A variety of techniques are used for this purpose, including profile counting, partial and whole-body scanning by LFOV gamma camera and whole-body counting, in addition to the analysis of radioactivity in blood and excreta. The use of these techniques is illustrated for the acquisition of biokinetic data and subsequent dosimetry of three novel radiopharmaceuticals: 77 Br-p-bromospiperone (quantification of dopamine receptors in the brain). 99 Tc/sup m/-porphyrins and 99 Tc/sup m/ DEPE (a possible novel blood pool marker for MUGA studies). 14 references, 14 figures, 2 tables

Proposal of a new biokinetic model for niobium; Proposta de um novo modelo biocinetico para o niobio

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Roges

2006-07-01

There are two niobium isotopes generated in nuclear power plants: 95 Nb and 94 Nb. Workers and members of the public are subjects to intake these radionuclides in accident situation. For dose calculation purpose, it is very important to develop a model that describes in a more realistic way the kinetics of niobium inside of the human body. Presently the model adopted by ICRP (ICRP, 1989) is based on animal studies and describes the behavior of niobium in human being in a simple manner. The new model proposal describes the kinetics of the niobium from the intake into the blood until the excretion, doing this in a more realistic form and considering not only data from animals but data from human beings as well. For this objective, a workers group of a niobium extraction and processing industry exposed to stable niobium (93 Nb) in oxide insoluble form with associated uranium, was monitored for uranium and niobium determination in urinary and fecal excretion, by mass spectrometry. Based in the ratios of the niobium concentration in urinary and faecal excretion of this workers and animal data study, a new biokinetic model for niobium was proposed, with the followings modifications relative to ICRP model: a new compartment that represents muscular tissue; the fractions which are deposited into the compartment are modified; a third component in the retention equation of the bone tissue; introduction of recirculation between organs and blood. The new model was applied for a case of accidental intake and described adequately the experimental data.

Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

Energy Technology Data Exchange (ETDEWEB)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J. (Oregon State Univ., Newport (USA). Marine Science Center)

1982-10-01

The biokinetic behavior of sup(95m)Tc in the red abalone, haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of sup(95m)Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, approximately equal to 45% and loss kinetics are similar to those observed following direct uptake from seawater.

Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

Energy Technology Data Exchange (ETDEWEB)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

1982-10-01

The biokinetic behavior of /sup 95m/Tc in the red abalone, Haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labelled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of /sup 95m/Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, is approximately 45% and loss kinetics are similar to those observed following direct uptake from seawater.

Biokinetic behavior of technetium in the red abalone, Haliotis rufescens: a re-assessment

International Nuclear Information System (INIS)

Beasley, T.M.; Lorz, H.V.; Gonor, J.J.

1982-01-01

The biokinetic behavior of sup(95m)Tc in the red abalone, haliotis rufescens, is reviewed in light of recent experiments with other molluscs. Additional experimentation has confirmed that, when uptake is directly from labeled seawater, abalones exhibit concentration factors in excess of 100. Bivalve molluscs under the same experimental conditions have concentration factors that do not exceed 2. However, uptake and loss kinetics in the abalone cannot be described by a single compartment model as had been previously advanced. Assimilation of sup(95m)Tc by abalones following a single feeding of labeled macroalga, Nereocystis luetkeana, approximately equal to 45% and loss kinetics are similar to those observed following direct uptake from seawater. (author)

Comparison of predicted with observed biokinetics of inhaled plutonium nitrate and gadolinium oxide in humans

International Nuclear Information System (INIS)

Hodgson, A.; Shutt, A.L.; Etherington, G.; Hodgson, S.A.; Rance, E.; Stradling, G.N.; Youngman, M.J.; Ziesenis, A.; Kreyling, W.G.

2003-01-01

The absorption kinetics to blood of plutonium and gadolinium after inhalation as nitrate and oxide in humans and animals has been studied. For each material, values describing the time dependence of absorption were derived from the studies in animals and used with the ICRP human respiratory tract model to predict lung retention and cumulative amounts to blood for the volunteers inhaling the same materials. Comparison with the observed behaviour in the volunteers suggests that absorption of plutonium and gadolinium is reasonably species independent, and that data obtained from animal studies can be used to assess their biokinetic behaviour in humans. (author)

Biokinetics and dosimetry of target-specific radiopharmaceuticals for molecular imaging and therapy

International Nuclear Information System (INIS)

Ferro F, G.; Torres G, E.; Gonzalez V, A.; Murphy, C.A. de

2006-01-01

Molecular imaging techniques directly or indirectly monitor and record the spatiotemporal distribution of molecular or cellular processes for biochemical, biologic, diagnostic or therapeutic applications. 99m Tc-HYNlC-TOC has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. Therapies using radiolabeled anti-CD20 have demonstrated their efficacy in patients with B-cell non Hodgkin's Iymphoma (NHL). The aim of this study was to establish biokinetic models for 99m Tc-HYNlC-TOC and 188 Re-anti-CD20 prepared from Iyophilized kits, and to evaluate their dosimetry as target-specific radiopharmaceuticals. Whole-body images were acquired at different times after 99m Tc-HYNlC-TOC or 188 Re-anti-CD20 administration obtained from instant freeze-dried kit formulations with radiochemical purities > 95 %. Regions of interest (ROls) were drawn around source organs on each time frame. The cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate time-activity curves in each organ, to adjust the biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. 99m Tc-HYNlC-TOC images showed an average tumor/blood (heart) ratio of 4.3 ± 0.7 in receptor-positive tumors at 1 h and the mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv. Results showed that after administration of 7 GBq of 188 Re-anti-CD20 the absorbed dose to whole body would be 0.7 Gy (0.1 mGy/MBq) which is the indicated dose for non Hodgkin's Iymphome therapies. (Author)

Amiodarone biokinetics, the formation of its major oxidative metabolite and neurotoxicity after acute and repeated exposure of brain cell cultures.

Science.gov (United States)

Pomponio, Giuliana; Zurich, Marie-Gabrielle; Schultz, Luise; Weiss, Dieter G; Romanelli, Luca; Gramowski-Voss, Alexandra; Di Consiglio, Emma; Testai, Emanuela

2015-12-25

The difficulty in mimicking nervous system complexity and cell-cell interactions as well as the lack of kinetics information has limited the use of in vitro neurotoxicity data. Here, we assessed the biokinetic profile as well as the neurotoxicity of Amiodarone after acute and repeated exposure in two advanced rodent brain cell culture models, consisting of both neurons and glial cells organized in 2 or 3 dimensions to mimic the brain histiotypic structure and function. A strategy was applied to evidence the abiotic processes possibly affecting Amiodarone in vitro bioavailability, showing its ability to adsorb to the plastic devices. At clinically relevant Amiodarone concentrations, known to induce neurotoxicity in some patients during therapeutic treatment, a complete uptake was observed in both models in 24 h, after single exposure. After repeated treatments, bioaccumulation was observed, especially in the 3D cell model, together with a greater alteration of neurotoxicity markers. After 14 days, Amiodarone major oxidative metabolite (mono-N-desethylamiodarone) was detected at limited levels, indicating the presence of active drug metabolism enzymes (i.e. cytochrome P450) in both models. The assessment of biokinetics provides useful information on the relevance of in vitro toxicity data and should be considered in the design of an Integrated Testing Strategy aimed to identify specific neurotoxic alerts, and to improve the neurotoxicity assay predictivity for human acute and repeated exposure. Copyright © 2015 Elsevier Ltd. All rights reserved.

Biokinetic study of plutonium and americium associated to the particulates of soil

International Nuclear Information System (INIS)

Espinosa, A.; Aragon, A.; Martinez, J.; Iranzo, C.E.

1996-01-01

The object of this study is to determine the biokinetic parameters of different Plutonium isotopes and Americium inhaled in the state in which they are found in the environment as a result of their deposition in the soil, from an aviation accident that generated different plutonium oxides. to achieve this objective, two lines of work planned. One was the determination of the mineralogical composition and associations that plutonium and americium present in that soil 22 years after the nuclear accident. Other studies were directed to determine the biokinetic of the plutonium isotopes and americium (contained in the dust) deposited tracheally and inhaled by laboratory animals (rats) and in vitro experiments by pulmonary leaching simulation. The in vivo tests have been developed in NRPB (U.K.) and the in vitro experiment, geochemical associations studies, assessment of internal doses to humans resulting from intake of plutonium and americium bearing dusts present in the contaminated area and establishment of ALIs for inhalation, were carried out in CIEMAT (Spain). In this work only determinations and experiments carried out by CIEMAT are includes as a part of the EU Project ''INHALATION AND INGESTION OF RADIONUCLIDES'' contract: FI3P-CT920064a. (Author) 10 refs

Cost-benefit analysis for a lead wheel weight phase-out in Canada.

Science.gov (United States)

Campbell, P M; Corneau, E; Nishimura, D; Teng, E; Ekoualla, D

2018-05-06

Lead wheel weights (LWWs) have been banned in Europe, and some US States, but they continue to dominate the market in Canada. Exposure to lead is associated with numerous health impacts and can result in multiple and irreversible health problems which include cognitive impairment when exposure occurs during early development. Such impacts incur high individual and social costs. The purpose of this study was to assess the costs and public health benefits of a Risk Management Strategy (RMS) that would result from a LWW phase-out in Canada and compare this to a Business-As-Usual (BAU) scenario. The contribution of LWWs to lead concentrations in media including roadway soil/dust, ambient and indoor air, and indoor dust were estimated. The Integrated Exposure Uptake Biokinetic Model for Lead in Children (IEUBK) was used to develop estimates for the blood lead levels (BLLs) in children (μg/dL) associated with the BAU and the RMS. The BLLs estimated via the IEUBK model were then used to assess the IQ decrements associated with the BAU that would be avoided under the RMS. The subsequent overall societal benefits in terms of increased lifetime earning potential and reduced crime rate, were then estimated and compared to industry and government costs. LWWs form 72% of the Canadian wheel weight market and >1500 tonnes of lead as new LWWs attached to vehicles enters Canadian society annually. We estimate that 110-131 tonnes of lead in detached WWs are abraded on roadways in Canada each year. A LWW phase-out was predicted to result in a drop in pre-school BLLs of up to 0.4 μg/dL. The estimated net benefits associated with the RMS based on cognitive decrements avoided and hence increased lifetime earning potential (increased productivity) and reduced crime are expected to be: C$248 million (8% discount rate) to C$1.2 billion (3% discount rate) per year. Copyright © 2018 Elsevier B.V. All rights reserved.

Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996 - 1999. Mid-term reports for the period 1996-1997

Energy Technology Data Exchange (ETDEWEB)

Jacob, P.; Paretzke, H.G.; Roth, P. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Michael, B.D. [Mount Vernon Hospital, Northwood (United Kingdom). Gray Lab.; O`Sullivan, D. [Dublin Inst. for Advanced Studies (Ireland)

1998-12-31

The main objectives of the first dosimetry project are the measurement of neutron and charged particle flux and energy spectra at altitudes in civil aviation, the determination of response characteristics for detectors, the investigation of calibration procedures, and the evaluation of exposures of aircrews. The overall objective of the second dosimetry project is to improve estimates of dose following the intake of radionuclides by adults and children. The work includes the development of biokinetic and dosimetric models, including models of the gastrointestinal tract, for the systemic behaviour of radionuclides, and for the developing embryo and foetus. Further subjects are target cell dosimetry for short-range particles and the development of computational tools for sensitivity and uncertainty analysis models. The third dosimetry project encompasses the study of different methods for retrospective dose assessments for individuals or groups of individuals accidentally exposed to increased levels of radiation. The methods investigated include electron paramagnetic resonance (EPR) of tooth enamel and chromosome painting (FISH) for lymphocytes in peripheral blood for individual retrospective dose assessments, luminescence techniques on materials in inhabited environment (ceramics, bricks) and model calculations using environmental data as input. (orig.)

Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996 - 1999. Mid-term reports for the period 1996-1997

Energy Technology Data Exchange (ETDEWEB)

Jacob, P; Paretzke, H G; Roth, P [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Michael, B D [Mount Vernon Hospital, Northwood (United Kingdom). Gray Lab.; O` Sullivan, D [Dublin Inst. for Advanced Studies (Ireland)

1999-12-31

The main objectives of the first dosimetry project are the measurement of neutron and charged particle flux and energy spectra at altitudes in civil aviation, the determination of response characteristics for detectors, the investigation of calibration procedures, and the evaluation of exposures of aircrews. The overall objective of the second dosimetry project is to improve estimates of dose following the intake of radionuclides by adults and children. The work includes the development of biokinetic and dosimetric models, including models of the gastrointestinal tract, for the systemic behaviour of radionuclides, and for the developing embryo and foetus. Further subjects are target cell dosimetry for short-range particles and the development of computational tools for sensitivity and uncertainty analysis models. The third dosimetry project encompasses the study of different methods for retrospective dose assessments for individuals or groups of individuals accidentally exposed to increased levels of radiation. The methods investigated include electron paramagnetic resonance (EPR) of tooth enamel and chromosome painting (FISH) for lymphocytes in peripheral blood for individual retrospective dose assessments, luminescence techniques on materials in inhabited environment (ceramics, bricks) and model calculations using environmental data as input. (orig.)

Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996 - 1999. Mid-term reports for the period 1996-1997

International Nuclear Information System (INIS)

Jacob, P.; Paretzke, H.G.; Roth, P.

1998-01-01

The main objectives of the first dosimetry project are the measurement of neutron and charged particle flux and energy spectra at altitudes in civil aviation, the determination of response characteristics for detectors, the investigation of calibration procedures, and the evaluation of exposures of aircrews. The overall objective of the second dosimetry project is to improve estimates of dose following the intake of radionuclides by adults and children. The work includes the development of biokinetic and dosimetric models, including models of the gastrointestinal tract, for the systemic behaviour of radionuclides, and for the developing embryo and foetus. Further subjects are target cell dosimetry for short-range particles and the development of computational tools for sensitivity and uncertainty analysis models. The third dosimetry project encompasses the study of different methods for retrospective dose assessments for individuals or groups of individuals accidentally exposed to increased levels of radiation. The methods investigated include electron paramagnetic resonance (EPR) of tooth enamel and chromosome painting (FISH) for lymphocytes in peripheral blood for individual retrospective dose assessments, luminescence techniques on materials in inhabited environment (ceramics, bricks) and model calculations using environmental data as input. (orig.)

Controlling intake of uranium in the workplace: Applications of biokinetic modeling and occupational monitoring data

Energy Technology Data Exchange (ETDEWEB)

Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; McGinn, Wilson [ORNL; Meck, Dr. Robert A. [U.S. Nuclear Regulatory Commission

2012-01-01

This report provides methods for interpreting and applying occupational uranium monitoring data. The methods are based on current international radiation protection guidance, current information on the chemical toxicity of uranium, and best available biokinetic models for uranium. Emphasis is on air monitoring data and three types of bioassay data: the concentration of uranium in urine; the concentration of uranium in feces; and the externally measured content of uranium in the chest. Primary Reference guidance levels for prevention of chemical effects and limitation of radiation effects are selected based on a review of current scientific data and regulatory principles for setting standards. Generic investigation levels and immediate action levels are then defined in terms of these primary guidance levels. The generic investigation and immediate actions levels are stated in terms of radiation dose and concentration of uranium in the kidneys. These are not directly measurable quantities, but models can be used to relate the generic levels to the concentration of uranium in air, urine, or feces, or the total uranium activity in the chest. Default investigation and immediate action levels for uranium in air, urine, feces, and chest are recommended for situations in which there is little information on the form of uranium taken into the body. Methods are prescribed also for deriving case-specific investigation and immediate action levels for uranium in air, urine, feces, and chest when there is sufficient information on the form of uranium to narrow the range of predictions of accumulation of uranium in the main target organs for uranium: kidneys for chemical effects and lungs for radiological effects. In addition, methods for using the information herein for alternative guidance levels, different from the ones selected for this report, are described.

A novel bench-scale column assay to investigate site-specific nitrification biokinetics in biological rapid sand filters

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2013-01-01

A bench-scale assay was developed to obtain site-specific nitrification biokinetic information from biological rapid sand filters employed in groundwater treatment. The experimental set-up uses granular material subsampled from a full-scale filter, packed in a column, and operated with controlled...

Physiologically based pharmacokinetics model for estimating urinary excretion of short half-life nuclides in nuclear medicine

International Nuclear Information System (INIS)

Akahane, K.; Kai, M.; Konishi, E.; Kusama, T.; Aoki, Y.

1995-01-01

The biokinetic model in ICRP 53 is used for calculating absorbed dose to each organ of a patient in nuclear medicine. The ICRP model is a simple compartment model based on human data; however, the model cannot produce the biokinetics of radiopharmaceuticals under various physiological conditions. On the other hand, a physiologically based pharmacokinetics model (PBPK model) can describe the flow of radiopharmaceuticals as a compartment model for any physiological conditions theoretically. The PBPK model was applied especially for the kidney-bladder dynamics, and similar results obtained compared with the ICRP model. This suggests the possibility of the PBPK model for predicting the biokinetics of radiopharmaceuticals under various physiological conditions. (Author)

Biokinetics and dosimetry in patients of 99mTc-EDDA/HYNIC-Tyr3-octreotide prepared from lyophilized kits

International Nuclear Information System (INIS)

Gonzalez-Vazquez, Armando; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Gutierrez-Garcia, Zohar

2006-01-01

99m Tc-EDDA/HYNIC-Tyr 3 -octreotide ( 99m Tc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for 99m Tc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after 99m Tc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3±0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv

Biokinetics and dosimetry in patients of 99mTc-EDDA/HYNIC-Tyr3-octreotide prepared from lyophilized kits.

Science.gov (United States)

González-Vázquez, Armando; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Gutiérrez-García, Zohar

2006-07-01

99mTc-EDDA/HYNIC-Tyr3-octreotide (99mTc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for 99mTc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after 99mTc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99mTc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3+/-0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv.

Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2016-01-01

The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous...

The in vitro biokinetics of chlorpromazine and diazepam in aggregating rat brain cell cultures after repeated exposure

NARCIS (Netherlands)

Broeders, Jessica J W; Hermens, Joop L M; Blaauboer, Bas J; Zurich, Marie-Gabrielle

2015-01-01

Neurotoxic effects of compounds can be tested in vitro using cell systems. One example is aggregating rat brain cell cultures. For the extrapolation of in vitro data to the in vivo situation, it is important to take the biokinetics of the test compound into account. In addition, the exposure in vivo

Biokinetics of radiotellurium in rats

International Nuclear Information System (INIS)

Nishimura, Y.; Sahoo, S.K.; Kim, S.; Homma-Takeda, S.; Watanabe, Y.; Inaba, J.

2003-01-01

Radiotellurium is present in the environment primarily due to its release during nuclear reactor accidents. Little is known of tellurium metabolism in juveniles, although the element is relatively abundant and has a number of industrial uses. A biokinetic study of radiotellurium in rats was done using gamma-ray counting. Wistar strain rats were used to determine the uptake of H 2 123 Te m O 3 by the whole-body retention of juvenile rats and the conceptus in relation to its gestational stages, by measurements in the placenta, fetal membranes, fetal fluid, and fetus. The whole-body retention of 123 Te m in juvenile rats was higher than that of adult rats. The relative concentration in the placenta and fetal membranes was higher than in the fetus. No activity was observed in the fetal fluid. These results indicate that the placenta and fetal membranes play significant roles as barriers to the transfer of 123 Te m into the fetus. The ratio, relative concentration in fetus/relative concentration in mother (C F /C M ), was calculated. The C F /C M ratio was dependent on the stage of gestation and ranged from 0.2 to 0.5. A little 123 Te m was transferred to the suckling rats through the mother's milk when the isotope was administered intravenously to the mother. (author)

Parametric study of a thorium model

International Nuclear Information System (INIS)

Lourenco, M.C.; Lipsztein, J.L.; Szwarcwald, C.L.

2002-01-01

Models for radionuclides distribution in the human body and dosimetry involve assumptions on the biokinetic behavior of the material among compartments representing organs and tissues in the body. One of the most important problem in biokinetic modeling is the assignment of transfer coefficients and biological half-lives to body compartments. In Brazil there are many areas of high natural radioactivity, where the population is chronically exposed to radionuclides of the thorium series. The uncertainties of the thorium biokinetic model are a major cause of uncertainty in the estimates of the committed dose equivalent of the population living in high background areas. The purpose of this study is to discuss the variability in the thorium activities accumulated in the body compartments in relation to the variations in the transfer coefficients and compartments biological half-lives of a thorium-recycling model for continuous exposure. Multiple regression analysis methods were applied to analyze the results. (author)

Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat

International Nuclear Information System (INIS)

Monleau, M.

2005-12-01

Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure. It

Performance analysis of numeric solutions applied to biokinetics of radionuclides; Analise de desempenho de solucoes numericas aplicadas a biocinetica de radionuclideos

Energy Technology Data Exchange (ETDEWEB)

Mingatos, Danielle dos Santos; Bevilacqua, Joyce da Silva, E-mail: dani@ime.usp.br, E-mail: joyce@ime.usp.br [Universidade de Sao Paulo (IME/USP), SP (Brazil). Instituto de Matematica e Estatistica; Todo, Alberto Saburo; Rodrigues Junior, Orlando, E-mail: astodo@ipen.br, E-mail: rodrijr@ipen.br [Instituto de Pesquisas Energeticas Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2013-07-01

Biokinetics models for radionuclides applied to dosimetry problems are constantly reviewed by ICRP. The radionuclide trajectory could be represented by compartmental models, assuming constant transfer rates between compartments. A better understanding of physiological or biochemical phenomena, improve the comprehension of radionuclide behavior in the human body and, in general, more complex compartmental models are proposed, increasing the difficulty of obtaining the analytical solution for the system of first order differential equations. Even with constant transfer rates numerical solutions must be carefully implemented because of almost singular characteristic of the matrix of coefficients. In this work we compare numerical methods with different strategies for ICRP-78 models for Thorium-228 and Uranium-234. The impact of uncertainty in the parameters of the equations is also estimated for local and global truncation errors. (author)

Dosimetric evaluation in organs of the Tc99m, I123 bio-kinetics to estimate dose in thyroid children 1 and 5 years

International Nuclear Information System (INIS)

Vasquez, A. M.; Quispe, R.; Vasquez, D. J.; Rocha, M. D.; Morales, N. R.; Marin, R. K.; Zelada, A. L.

2012-10-01

Using the formalism MIRD and the representation of Cristy-Eckerman for the thyroid in children of 1 and 5 years, is demonstrated that the dosimetric contribution of the organs of I 123 (iodure) bio-kinetics is not significant in the dose estimate. The total dose absorbed by the gland is its auto dose. The dosimetric contribution of the organs source of the Tc 99m (pertechnetate) bio-kinetics in the gland is significant in the dose estimate like to be ignored. The reported results for the iodure are not significantly different to the found for the Marinelli scheme (auto-dose) for thyroid represented by a sphere of 1,78 and 3,45 grams. (Author)

Biokinetic and dosimetric studies of 188Re-hyaluronic acid: a new radiopharmaceutical for treatment of hepatocellular carcinoma

International Nuclear Information System (INIS)

Melendez-Alafort, Laura; Nadali, Anna; Zangoni, Elena; Banzato, Alessandra; Rondina, Maria; Rosato, Antonio; Mazzi, Ulderico

2009-01-01

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has very limited therapeutic options. Recently, it has been found that hyaluronic acid (HA) shows selective binding to CD44 receptors expressed in most cancer histotypes. Since the trend in cancer treatment is the use of targeted radionuclide therapy, the aim of this research was to label HA with rhenium-188 and to evaluate its potential use as a hepatocarcinoma therapeutic radiopharmaceutical. Methods: 188 Re-HA was prepared by a direct labelling method to produce a ReO(O-COO) 2 -type coordination complex. 188 Re-HA protein binding and its stability in saline, phosphate buffer, human serum and cysteine solutions were determined. Biokinetic and dosimetric data were estimated in healthy mice (n=60) using the Medical Internal Radiation Dose methodology and mouse model beta-absorbed fractions. To evaluate liver toxicity, alanine aminotranferase (AST) and aspartate aminotranferase (ALT) levels in mice were assessed and the liver maximum tolerated dose (MTD) of 188 Re-HA was determined. Results: A stable complex of 188 Re-HA was obtained with high radiochemical purity (>90%) and low serum protein binding (2%). Biokinetic studies showed a rapid blood clearance (T 1/2 α=21 min). Four hours after administration, 188 Re-HA was almost totally removed from the blood by the liver due to the selective uptake via HA-specific receptors (73.47±5.11% of the injected dose). The liver MTD in mice was ∼40 Gy after 7.4 MBq of 188 Re-HA injection. Conclusions: 188 Re-HA complex showed good stability, pharmacokinetic and dosimetric characteristics that confirm its potential as a new agent for HCC radiation therapy.

Biokinetics and dosimetry in patients of {sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-octreotide prepared from lyophilized kits

Energy Technology Data Exchange (ETDEWEB)

Gonzalez-Vazquez, Armando [Departamento de Medicina Nuclear, Hospital Militar (Mexico); Facultad de Medicina, Universidad Autonoma del Estado de Mexico (Mexico); Ferro-Flores, Guillermina [Departamento de Materiales Radiactivos, Gerencia de Aplicaciones Nucleares en la Salud, Instituto Nacional de Investigaciones Nucleares, Km. 36.5 Carretera Mexico-Toluca, Ocoyoacac, Estado de Mexico, C.P. 52045 (Mexico)]. E-mail: gff@nuclear.inin.mx; Arteaga de Murphy, Consuelo [Departamento de Medicina Nuclear, Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran (Mexico); Gutierrez-Garcia, Zohar [Departamento de Medicina Nuclear, Hospital Militar (Mexico)

2006-07-15

{sup 99m}Tc-EDDA/HYNIC-Tyr{sup 3}-octreotide ({sup 99m}Tc-HYNIC-TOC) has shown high in vitro and in vivo stability, rapid background clearance and rapid detection of somatostatin receptor-positive tumors. The aim of this study was to establish a biokinetic model for {sup 99m}Tc-HYNIC-TOC prepared from lyophilized kits, and to evaluate its dosimetry as a tumor imaging agent in patients with histologically confirmed neuroendocrine tumors. Whole-body images from eight patients were acquired at 5, 60, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-TOC administration obtained from instant freeze-dried kit formulations with radiochemical purities >95%. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all eight scans and the count per minute (cpm) of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-TOC time-activity curves in each organ, to adjust a biokinetic model using the SAAM software, and to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed an average tumor/blood (heart) ratio of 4.3{+-}0.7 in receptor-positive tumors at 1 h. The mean radiation absorbed dose calculated for a study using 740 MBq was 24, 21.5, 5.5 and 1.0 mSv for spleen, kidneys, liver and bone marrow respectively and the effective dose was 4.4 mSv.

Biokinetics and dosimetry of a hybrid formulation of 9mTc-BN and 99mTc-RGD2 starting from optic images in a murine model

International Nuclear Information System (INIS)

Cornejo A, L. G.

2015-01-01

This work has the purpose of evaluate the biokinetics and absorbed dose of radiation of hybrid formulation 99m Tc-BN / 99m Tc-RGD 2 in a murine model by optical imaging techniques using the multimodal preclinical in vivo image system Xtreme. The used method were the 99m Tc-BN, 99m Tc-RGD 2 and 99m Tc-BN/ 99m Tc-RGD 2 formulas, with specific recognition for GRPr and the integrin s α(v)β(3) and α(v)β(5) respectively, was injected in the vein tail of three nude mousses with induce breast cancer tumors (cell line T-47-D), by the preclinical multimodal imaging system Xtreme (Bruker), optical images in different times was acquired (5, 10, 20 min, 2 and 24 h), using Images Processing Toolbox of MATLAB these images was transform from RGB format to gray scales and sectioned in five independent images corresponding to heart, kidneys, bladder and tumor areas. The intensity of each images was computed in counts per pixel, then those intensities was corrected for background, attenuation and scattering, using different factors for each phenomena previously calculated. Finally the activity values quantified vs time was fitted into a biokinetic model to obtain the disintegrations number and cumulate activities in each organ. With these data the radiation absorbed dose were calculated using MIRD methodology. Results: The number of disintegration and absorbed dose calculated in MBq h/MBq and mGy/MBq, of injected mouse with the 99m Tc-BN/ 99m Tc-RGD 2 formulation, was: 0.035 ± 0.65 E-02, 0.25 x 10 -5 ± 0.46 E-07; 0.393 ± 0.51 E-1, 2.85 E-05 ± 3.7 E-06; 0.306 ± 0.21 E-01, 2.11 E-05 ± 1.45 E-06 and 0.151 ± 0.19 E-01, 1.09 E-05 ± 1.42 E-06 , in heart, kidneys, bladder and tumor, respectively. The number of disintegration obtained in kidneys is comparable to those reported for Trinidad B. 2014 Conclusions: Our results demonstrated that using optical images and a code for image analyses development in MATLAB, could achieve comparable quantitative results as the conventional

Reliability of the ICRP's dose coefficients for members of the public: IV. Basis of the human alimentary tract model and uncertainties in model predictions

International Nuclear Information System (INIS)

Leggett, R.; Harrison, J.; Phipps, A.

2007-01-01

The biokinetic and dosimetric model of the gastrointestinal (GI) tract applied in current documents of the International Commission on Radiological Protection (ICRP) was developed in the mid-1960's. The model was based on features of a reference adult male and was first used by the ICRP in Publication 30, Limits for Intakes of Radionuclides by Workers (Part 1, 1979). In the late 1990's an ICRP task group was appointed to develop a biokinetic and dosimetric model of the alimentary tract that reflects updated information and addresses current needs in radiation protection. The new age-specific and gender-specific model, called the Human Alimentary Tract Model (HATM), has been completed and will replace the GI model of Publication 30 in upcoming ICRP documents. This paper discusses the basis for the structure and parameter values of the HATM, summarises the uncertainties associated with selected features and types of predictions of the HATM and examines the sensitivity of dose estimates to these uncertainties for selected radionuclides. Emphasis is on generic biokinetic features of the HATM, particularly transit times through the lumen of the alimentary tract, but key dosimetric features of the model are outlined, and the sensitivity of tissue dose estimates to uncertainties in dosimetric as well as biokinetic features of the HATM are examined for selected radionuclides. (authors)

Multigenerational cadmium acclimation and biokinetics in Daphnia magna

International Nuclear Information System (INIS)

Guan Rui; Wang Wenxiong

2006-01-01

A Cd exposure (3 μg L -1 ) experiment was conducted for six successive generations to investigate the responses to chronic Cd stress in Daphnia magna. We observed a biphasic accumulation of Cd in the six generations and suggested a similar pattern with respect to daphnids' tolerance. Cd assimilation efficiencies, daphnid growth, and reproduction corresponded to the changes of tolerance, which was partially accounted for by metallothionein induction. When maternally exposed neonates grew in Cd-free water for one or two generations, their growth, MT concentration and biokinetic parameters partially or totally recovered. The rapid recovery suggests the high potential for ecological restoration from Cd pollution. Our results indicate that the tolerance of sensitive D. magna clones to Cd was dependent on long-term or multigenerational exposure. The tolerance developed within the first several generations might not be maintained, and the animals may become even more sensitive to Cd stress in subsequent generations. - Tolerance of sensitive Daphnia magna clones to cadmium was dependent on long-term or multigenerational exposure

Distribution and biokinetic analysis of {sup 210}Pb and {sup 210}Po in poultry due to ingestion of dicalcium phosphate

Energy Technology Data Exchange (ETDEWEB)

Casacuberta, N., E-mail: Nuria.Casacuberta@uab.es [Departament de Fisica and Institut de Ciencia i Tecnologia Ambientals, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Traversa, F.L. [Departament d' Electronica, Escola Tecnica Superior d' Enginyeria, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Masque, P.; Garcia-Orellana, J. [Departament de Fisica and Institut de Ciencia i Tecnologia Ambientals, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Anguita, M.; Gasa, J. [Departament de Ciencia Animal i dels Aliments, Universitat Autonoma de Barcelona, 08193 Bellaterra (Spain); Garcia-Tenorio, R. [Universidad de Sevilla, Avda. Reina Mercedes s/n, 41012 Sevilla (Spain)

2010-09-15

Dicalcium phosphate (DCP) is used as a calcium supplement for food producing animals (i.e., cattle, poultry and pig). When DCP is produced via wet acid digestion of the phosphate rock and depending on the acid used in the industrial process, the final product can result in enhanced {sup 210}Pb and {sup 210}Po specific activities ({approx} 2000 Bq.kg{sup -1}). Both {sup 210}Pb and {sup 210}Po are of great interest because their contribution to the dose received by ingestion is potentially large. The aims of this work are to examine the accumulation of {sup 210}Pb and {sup 210}Po in chicken tissues during the first 42 days of life and to build a suitable single-compartment biokinetic model to understand the behavior of both radionuclides within the entire animal using the experimental results. Three commercial corn-soybean-based diets containing different amounts and sources of DCP were fed to broilers during a period of 42 days. The results show that diets containing enhanced concentrations of {sup 210}Pb and {sup 210}Po lead to larger specific accumulation in broiler tissues compared to the blank diet. Radionuclides do not accumulate homogeneously within the animal body: {sup 210}Pb follows the calcium pathways to some extent and accumulates largely in bones, while {sup 210}Po accumulates to a large extent in liver and kidneys. However, the total amount of radionuclide accumulation in tissues is small compared to the amounts excreted in feces. The single-compartment non-linear biokinetic model proposed here for {sup 210}Pb and {sup 210}Po in the whole animal takes into account the size evolution and is self-consistent in that no fitting parameterization of intake and excretions rates is required.

A review of contributions of human tissue studies to biokinetics, bio-effects and dosimetry of plutonium in man

International Nuclear Information System (INIS)

Kathren, R. L.

2004-01-01

This paper briefly reviews the contributions made by human tissue studies to improved understanding of the biokinetics, dosimetry and potential bio-effects of plutonium in man. It includes consideration of tissue donations from both environmental and occupational populations, along with a brief history of human experience with plutonium and consideration of the bio-ethical aspects of post-mortem human tissue sampling. (authors)

The biokinetics and radiotoxicology of curium: A comparison with americium

Energy Technology Data Exchange (ETDEWEB)

Menetrier, F. [CEA, Fontenay-aux-Roses (France); Taylor, D.M. [School of Chemistry, Cardiff University, Cardiff CF10 3AT (United Kingdom)], E-mail: davtay@btinternet.com; Comte, A. [CEA, Fontenay-aux-Roses (France)

2008-05-15

The human and animal data on the biokinetics of {sup 242}Cm and {sup 244}Cm are reviewed and shown to be very similar to those for {sup 241}Am. Liver and skeleton are the main organs of deposition and the retention of curium in the skeleton is very prolonged in all the species examined. Retention of both curium and americium in the liver appears to be species-dependent, being relatively rapidly removed from the liver of rats, and probably humans, but being tenaciously retained in dogs and some other species. The radiotoxicity of curium is also reviewed and it is shown that, as with {sup 241}Am, lung and bone tumour induction are the major hazards from inhaled and systemically deposited {sup 244}Cm. The use of chelating agents for the treatment of accidental contamination of the human body with {sup 242,244}Cm is also discussed.

Biokinetic and dosimetric studies of {sup 188}Re-hyaluronic acid: a new radiopharmaceutical for treatment of hepatocellular carcinoma

Energy Technology Data Exchange (ETDEWEB)

Melendez-Alafort, Laura [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova, 35131 Padua (Italy); Nadali, Anna; Zangoni, Elena [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova, 35131 Padua (Italy); Banzato, Alessandra; Rondina, Maria [Dipartimento di Scienze Oncologiche e Chirurgiche, Universita degli Studi di Padova, Padua (Italy); Rosato, Antonio [Dipartimento di Scienze Oncologiche e Chirurgiche, Universita degli Studi di Padova, Padua (Italy); Istituto Oncologico Veneto, IOV, Padova, Padua (Italy); Mazzi, Ulderico [Dipartimento di Scienze Farmaceutiche, Universita degli Studi di Padova, 35131 Padua (Italy)

2009-08-15

Hepatocellular carcinoma (HCC) is the most common primary liver cancer and has very limited therapeutic options. Recently, it has been found that hyaluronic acid (HA) shows selective binding to CD44 receptors expressed in most cancer histotypes. Since the trend in cancer treatment is the use of targeted radionuclide therapy, the aim of this research was to label HA with rhenium-188 and to evaluate its potential use as a hepatocarcinoma therapeutic radiopharmaceutical. Methods: {sup 188}Re-HA was prepared by a direct labelling method to produce a ReO(O-COO){sub 2}-type coordination complex. {sup 188}Re-HA protein binding and its stability in saline, phosphate buffer, human serum and cysteine solutions were determined. Biokinetic and dosimetric data were estimated in healthy mice (n=60) using the Medical Internal Radiation Dose methodology and mouse model beta-absorbed fractions. To evaluate liver toxicity, alanine aminotranferase (AST) and aspartate aminotranferase (ALT) levels in mice were assessed and the liver maximum tolerated dose (MTD) of {sup 188}Re-HA was determined. Results: A stable complex of {sup 188}Re-HA was obtained with high radiochemical purity (>90%) and low serum protein binding (2%). Biokinetic studies showed a rapid blood clearance (T{sub 1/2}{alpha}=21 min). Four hours after administration, {sup 188}Re-HA was almost totally removed from the blood by the liver due to the selective uptake via HA-specific receptors (73.47{+-}5.11% of the injected dose). The liver MTD in mice was {approx}40 Gy after 7.4 MBq of {sup 188}Re-HA injection. Conclusions: {sup 188}Re-HA complex showed good stability, pharmacokinetic and dosimetric characteristics that confirm its potential as a new agent for HCC radiation therapy.

Effect of wastewater treatment on bio-kinetics of dissolved oxygen in Ravi river

International Nuclear Information System (INIS)

Haider, H.; Ali, W.

2010-01-01

Waste management studies are usually done using calibrated and verified water quality models. Ravi River located in Lahore, Pakistan is receiving untreated wastewater from number of out falls and . Surfaced rains and thus model calibration and verification are done using the data under the prevailing conditions. The water quality objectives can only be met with wastewater treatment wherein the model rate coefficients may change. The objective of this paper is to study the changes that may occur in these coefficients as a result of wastewater treatment. For this purpose, long-term BOD analyses have been carried out using river water and wastewater after different degrees of treatment. A laboratory scale biological reactor was used to study the effect of biological treatment on rate coefficients at 3, 6 and 10 days detention times. The study results show that CBOD biokinetic rate coefficient (K) reduces significantly from 0.25 day/sup -1/ for raw waste water to 0.1 day for the wastewater treatment for 3 days detention time in the biological reactor. Further reductions in the value of K to 0.07 day/sup -1 and 0.05 day/sup -1/ occurred for a treatment level corresponding to 6 and 10 days detention times, respectively. The NBOD rate coefficient (K/sub n/ was found to be 0.08 day/sup -1/ for 3 days detention time and 0.06 day/sup -1/ after treatment in the biological reactor at 6 and 10 days detention times. (author)

Parametric study of a thorium model

International Nuclear Information System (INIS)

Lourenco, M.C.; Lipztein, J.L.; Szwarcwald, C.L.

1997-01-01

Full text. Models for radionuclides distribution in the human body and dosimetry involve assumptions on the biokinetic behaviour of the material among compartments representing organs and tissues in the body. The lack of knowledge about the metabolic behaviour of a radionuclide represents a factor of uncertainty in estimates of committed dose equivalent. An important problem in biokinetic modeling is the correct assignment of transfer coefficients and biological half-lives to body compartments. The purpose of this study is to analyze the variability in the activities of the body compartments in relation to the variations in the transfer coefficients and compartments biological half-lives in a certain model. A thorium specific recycling model for continuous exposure was used. Multiple regression analysis methods were applied to analyze the results

Biokinetics of carbohydrate and lipid matabolism in normal laying hen; pt. 3

International Nuclear Information System (INIS)

Chiang, Y.H.; Riis, P.M.

1979-01-01

The radiochemical purity of sup(14)C(U)-glucose solution to be injected to normal laying hen was investigated for studying biokinetics of carbohydrate and lipid metabolism. The liquid scintillation counter was employed for determining the activity of carbon-14. The barium hydroxide and zinc sulfate were adopted to precipitate the protein in the solution. The glucose content in the solution was observed as 0.912 mg per ml. applying Hultman's method. The specific activity of sup(14)C(U)-glucose solution was known as 31.3 nCi/mg glucose. The glucose pentaacetate was synthesized to isolate the pure glucose from the solution. The specific activity of pure glucose was measured as 28.5 nCi/mg glucose. Therefore, it was known that the radiochemical purity of the solution was 82.7%. (Author)

Influence on dose coefficients for workers of the new metabolic models

International Nuclear Information System (INIS)

Gomez Parada, I.M.; Rojo, A.M.

1998-01-01

The International Commission on Radiological Protection (ICRP) has recently reviewed the biokinetic models used in the internal contamination dose assessment. ICRP has adopted a new model for the human respiratory tract and has updated, in ICRP Publications 56, 67 and 69, some of the biokinetic models of ICRP Publication 30. In this paper, the dose coefficients for some selected radionuclides issued in ICRP Publication 68 are compared with those obtained using the software LUPED (LUng Dose Evaluation Program). The former were calculated using the new systemic models, while the latter are based on the old metabolic models. The aim is to know to what extent the new models for systematic retention influence the dose coefficients for workers. (author) [es

Biokinetics of 13C in the human body after oral administration of 13C-labeled glucose as an index for the biokinetics of 14C.

Science.gov (United States)

Masuda, Tsuyoshi; Tako, Yasuhiro; Matsushita, Kensaku; Takeda, Hiroshi; Endo, Masahiro; Nakamura, Yuji; Hisamatsu, Shun'ichi

2016-09-01

The retention of 13 C in the human body after oral administration of 13 C-labeled glucose was studied in three healthy volunteer subjects to estimate the 50 year cumulative body burden for 13 C as an index of the committed dose of the radioisotope 14 C. After administration of 13 C-labeled glucose, the volunteers ingested controlled diets with a fixed number of calories for 112 d. Samples of breath and urine were collected up to 112 d after administration. Samples of feces were collected up to 14 d after administration. Hair samples were obtained at 119 d after administration and analyzed as a representative index of the rate of excretion of organic 13 C via pathways such as skin cell exfoliation and mucus secretion. All samples were analyzed for 13 C/ 12 C atomic ratio to determine the rate of excretion via each pathway. We then constructed a metabolic model with a total of four pathways (breath, urine, feces, and other) comprising seven compartments. We determined the values of the biokinetic parameters in the model by using the obtained excretion data. From 74% to 94% of the 13 C administered was excreted in breath, whereas    0.1). In addition, the dataset for one of the three subjects was markedly different from those of the other two. When we estimated the 50 year cumulative body burden for 13 C by using our model and we included non-statistically significant parameters, a considerable cumulative body burden was found in the compartments excreting to the other pathway. Although our results on the cumulative body burden of 13 C from orally administered carbon as glucose were inconclusive, we found that the compartments excreting to the other pathway had a markedly long residence time and therefore should be studied further to clarify the fate of carbon in the human body. In addition to excreta, data for serum and blood cell samples were also collected from the subjects to examine the metabolism of 13 C in human body.

Neighborhood level health risk assessment of lead paint removal activities from elevated steel bridges

Energy Technology Data Exchange (ETDEWEB)

Conway, R.F.; Cohen, J.T.; Bowers, T.

1999-07-01

The New York City Department of Transportation (NYCDOT) has adopted strict containment and monitoring procedures during paint removal activities on its bridges because of the increasing awareness about lead poisoning in children in urban environments and the potential risk of lead-based paint releases during those activities. NYCDOT owns nearly 800 bridges scattered throughout New York City. Before undertaking paint removal activities as part of its ongoing preventive maintenance and rehabilitation program, NYCDOT recently conducted an analysis to determine the public health risk posed to children living near them. The analysis the first of its kind to assess the actual public health risk potential during both routine operations and upset conditions, or accidental releases evaluated the total and incremental blood lead levels from paint removal activities on more than 5,000 children from 6 months to 6 years old. Increases in baseline blood lead levels were estimated using several models, including EPA's Integrated Exposure Uptake Biokinetic (IEUBK) Model. This model estimates steady-state blood lead levels in children, reflecting exposure to lead in multiple media over an extended period of time. Increases in lead exposure from paint removal activities in the area surrounding the bridges was estimated using EPA's Industrial Source Complex (ISC3) model to calculate ambient air and deposition levels. Potential releases from the containment and ancillary equipment used in the paint removal process were modeled based on different release scenarios ranging from routine operations to complete failure of containment. To estimate the paint removal activities' contribution to long-term exterior dust lead levels (and its related interior component), a stochastic simulation model was developed for each block in the study area.

Influence of selecting secondary settling tank sub-models on the calibration of WWTP models – A global sensitivity analysis using BSM2

DEFF Research Database (Denmark)

Ramin, Elham; Flores Alsina, Xavier; Sin, Gürkan

2014-01-01

This study investigates the sensitivity of wastewater treatment plant (WWTP) model performance to the selection of one-dimensional secondary settling tanks (1-D SST) models with first-order and second-order mathematical structures. We performed a global sensitivity analysis (GSA) on the benchmark...... simulation model No.2 with the input uncertainty associated to the biokinetic parameters in the activated sludge model No. 1 (ASM1), a fractionation parameter in the primary clarifier, and the settling parameters in the SST model. Based on the parameter sensitivity rankings obtained in this study......, the settling parameters were found to be as influential as the biokinetic parameters on the uncertainty of WWTP model predictions, particularly for biogas production and treated water quality. However, the sensitivity measures were found to be dependent on the 1-D SST models selected. Accordingly, we suggest...

Integration of the predictions of two models with dose measurements in a case study of children exposed to the emissions of a lead smelter

Energy Technology Data Exchange (ETDEWEB)

Bonnard, R.; McKone, T.E.

2009-03-01

The predictions of two source-to-dose models are systematically evaluated with observed data collected in a village polluted by a currently operating secondary lead smelter. Both models were built up from several sub-models linked together and run using Monte-Carlo simulation, to calculate the distribution children's blood lead levels attributable to the emissions from the facility. The first model system is composed of the CalTOX model linked to a recoded version of the IEUBK model. This system provides the distribution of the media-specific lead concentrations (air, soil, fruit, vegetables and blood) in the whole area investigated. The second model consists of a statistical model to estimate the lead deposition on the ground, a modified version of the model HHRAP and the same recoded version of the IEUBK model. This system provides an estimate of the concentration of exposure of specific individuals living in the study area. The predictions of the first model system were improved in terms of accuracy and precision by performing a sensitivity analysis and using field data to correct the default value provided for the leaf wet density. However, in this case study, the first model system tends to overestimate the exposure due to exposed vegetables. The second model was tested for nine children with contrasting exposure conditions. It managed to capture the blood levels for eight of them. In the last case, the exposure of the child by pathways not considered in the model may explain the failure of the model. The interest of this integrated model is to provide outputs with lower variance than the first model system, but at the moment further tests are necessary to conclude about its accuracy.

Dosimetric contribution of organs of biokinetics of {sup 99m}Tc and {sup 123}I to estimate radiation doses in thyroids of children of 1 and 5 years; Contribucion dosimetrica de organos de la biocinetica del {sup 99m}Tc y {sup 123}I para estimar dosis en tiroides de ninos de 1 y 5 anos

Energy Technology Data Exchange (ETDEWEB)

Vasquez, M.V.; Castillo, C.E.; Abanto, D.M.; Rocha, D.; Garcia, W.H.; Marin, K., E-mail: marvva@hotmail.com [Universidad Nacional de Trujillo (UNT), Trujillo (Peru); Quispe, R. [Centro de Ciencias Aplicadas y Desarrollo Tecnologico, UNAM, Mexico (Mexico)

2015-07-01

The absorbed doses by thyroids during uptake studies through biokinetics of radiopharmaceuticals containing {sup 123}I (iodine) or {sup 99m}Tc (pertechnetate) are estimated. Using the MIRD scheme and the representation of Cristy-Eckerman for thyroids in children of 1 and 5 years, the objective of the study was to determine whether the dosimetric biokinetic contributions of the organs of {sup 123}I (iodide) and {sup 99m}Tc (pertechnetate) biokinetic are significant in the estimated of the absorbed dose for thyroid uptake studies.

Bioaccessibility of Pb from ammunition in game meat is affected by cooking treatment.

Science.gov (United States)

Mateo, Rafael; Baos, Ana R; Vidal, Dolors; Camarero, Pablo R; Martinez-Haro, Monica; Taggart, Mark A

2011-01-14

The presence of lead (Pb) ammunition residues in game meat has been widely documented, yet little information exists regarding the bioaccessibility of this Pb contamination. We study how cooking treatment (recipe) can affect Pb bioaccessibility in meat of animals hunted with Pb ammunition. We used an in vitro gastrointestinal simulation to study bioaccessibility. The simulation was applied to meat from red-legged partridge (Alectoris rufa) hunted with Pb shot pellets and cooked using various traditional Spanish game recipes involving wine or vinegar. Total Pb concentrations in the meat were higher in samples with visible Pb ammunition by X-ray (mean±SE: 3.29±1.12 µg/g w.w.) than in samples without this evidence (1.28±0.61 µg/g). The percentage of Pb that was bioaccessible within the simulated intestine phase was far higher in meat cooked with vinegar (6.75%) and wine (4.51%) than in uncooked meat (0.7%). Risk assessment simulations using our results transformed to bioavailability and the Integrated Exposure Uptake Biokinetic model (IEUBK; US EPA) show that the use of wine instead of vinegar in cooking recipes may reduce the percentage of children that would be expected to have >10 µg/dl of Pb in blood from 2.08% to 0.26% when game meat represents 50% of the meat in diet. Lead from ammunition in game meat is more bioaccessible after cooking, especially when using highly acidic recipes. These results are important because existing theoretical models regarding Pb uptake and subsequent risk in humans should take such factors into account.

Bioavailability and Biokinetics of Anthocyanins From Red Grape Juice and Red Wine

Directory of Open Access Journals (Sweden)

Roland Bitsch

2004-01-01

Full Text Available In a comparative study, 9 healthy volunteers ingested a single oral dose of 400 mL red grape juice or red wine with dose-adjusted anthocyanin content (283.5 mg or 279.6 mg, resp. in crossover. The content of anthocyanin glucosides was detected in plasma and urinary excretion. Additionally, the plasmatic antioxidant activity was assessed after intake. Based on the plasma content, biokinetic criteria of the single anthocyanins were calculated, such as AUC, cmax, tmax, and the elimination rate t1/2. The urinary excretion of total anthocyanins differed significantly and amounted to 0.18% (red wine and 0.23% (red grape juice of the administered dose. Additionally, the plasmatic antioxidant activity increased to higher levels after juice ingestion compared to wine. The intestinal absorption of the anthocyanins of red grape juice seemed to be improved compared to red wine, suggesting a possible synergistic effect of the glucose content of the juice. The improved absorption resulted in an enhanced plasmatic bioactivity.

Empleo de isótopos radiactivos en estudios biocinéticos con animales de experimentación Use of radioisotopes in biokinetic models with experimental animals

Directory of Open Access Journals (Sweden)

F. R. Martín Martín

2002-06-01

Full Text Available En el presente trabajo se pretende realizar una revisión de las diferentes técnicas radioisotópicas que se utilizan con animales de experimentación a la hora de desarrollar modelos biocinéticos tanto de sustancias como de elementos químicos presentes en el medio ambiente. Dicha experimentación permite relacionar la exposición externa a un xenobiótico con la medida interna de la dosis en el organismo y, consecuentemente, sus posibles efectos tóxicos, todo ello con vistas a evaluar los efectos adversos que pudieran existir sobre la salud humana. Se hace hincapié en la macroautorradiografía de animal completo, técnica que permite la detección, localización y cuantificación del radionucleido de interés en diferentes órganos/tejidos del organismo y, por tanto, contribuye a la estimación de la dosis interna y al conocimiento del comportamiento biocinético del compuesto/elemento objeto de estudio. Se presentan algunos ejemplos de la utilidad de esta técnica en estudios biocinéticos con animales de experimentación de interés en diferentes áreas relacionadas con la Salud y el Medio Ambiente. Se destaca la utilidad que presenta esta experimentación a la hora de extrapolar el comportamiento metabólico de contaminantes de máxima radiotoxicidad en personas expuestas a la radiación ionizante, con el objeto de optimizar las evaluaciones dosimétricas y los protocolos de vigilancia que ayudan a conocer con más exactitud los daños de la exposición interna sobre la salud humana.Biokinetic models are useful tools to relate external exposures to internal measures of dose. The knowledge of internal dose and factors that influence absorption, distribution, metabolism, and elimination in experimental animals provide a scientific rationale for estimating low-dose human risk. A bioanalytical procedure to support biokinetic studies is the use of radiolabeled compounds, so that mass balance, autoradiography, and preliminary metabolism

Nanomaterial translocation - the biokinetics, tissue accumulation, toxicity and fate of materials in secondary organs

DEFF Research Database (Denmark)

Kermanizadeh, Ali; Balharry, Dominique; Wallin, Håkan

2015-01-01

into the toxicity posed by the NMs in these secondary organs is expanding due to the realisation that some materials may reach and accumulate in these target sites. The translocation to secondary organs includes, but is not limited to, the hepatic, central nervous, cardiovascular and renal systems. Current data...... dioxide and quantum dots) or fast (e.g. zinc oxide) solubility. The translocation of NMs following intratracheal, intranasal and pharyngeal aspiration is higher (up to 10% of administered dose), however the relevance of these routes for risk assessment is questionable. Uptake of the materials from....... For toxicological and risk evaluation, further information on the toxicokinetics and persistence of NMs is crucial. The overall aim of this review is to outline the data currently available in the literature on the biokinetics, accumulation, toxicity and eventual fate of NMs in order to assess the potential risks...

99mTc-exendin(9-39)/octreotide: biokinetics and radiation dosimetry in healthy individuals.

Science.gov (United States)

Ocampo-García, Blanca E; Santos-Cuevas, Clara L; Luna-Gutiérrez, Myrna A; Ignacio-Alvarez, Eleazar; Pedraza-López, Martha; Manzano-Mayoral, Cesar

2017-11-01

About 90% of insulinomas are benign and 5-15% are malignant. Benign insulinomas express the glucagon-like peptide-1 receptor (GLP-1R, which recognizes exendin-4 and low levels of the somatostatin receptor (SSTR, which recognizes octreotide), whereas malignant insulinomas overexpress SSTR and low levels of GLP-1R. Recently, Lys(Tc-EDDA/HYNIC)-exendin(9-39)/Tc-EDDA/HYNIC-Tyr-octreotide was formulated to detect 100% of insulinomas. The aim of this study was to estimate the biokinetics and dosimetry of Tc-exendin(9-39)/octreotide in four healthy individuals. Tc-exendin(9-39)/octreotide was obtained from a lyophilized formulation with radiochemical purities of more than 97%, determined by reversed-phase high-performance liquid chromatography. Whole-body images from four healthy individuals were acquired at 20 min, 2, 6, and 24 h after Tc-exendin(9-39)/octreotide administration. Regions of interest were drawn around the source organs on each time frame. Each region of interest was corrected by background, attenuation, scattered radiation, and physical decay. The image sequence was used to extrapolate the Tc-exendin(9-39)/octreotide time-activity curves of each organ to adjust the biokinetic model and calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation doses. Furthermore, in a patient suspicious of harboring an insulinoma, whole-body single-photon emission computed tomography/computed tomography images were obtained at 3 h. For four healthy individuals, the blood activity showed a half-life value of 1.20 min for the fast component (T1/2 α=ln 2/34.71), 8.7 min for the first slow component (T1/2 β=ln 2/4.76), and 1.7 h for the second slow component (T1/2 γ=ln 2/0.401). The average equivalent doses calculated for a study using 555 MBq were 15.10, 4.13, 3.08, 2.61, and 1.90 mSv for the kidneys, upper large intestinal wall, lower large

Selenium-75 and technetium-95m biokinetics in rats at different physiological states

International Nuclear Information System (INIS)

Archimbaud, Yves; Grillon, Gerard; Poncy, Jean-Luc; Masse, Roland

1992-06-01

Selenium 79 ( 79 Se) and technetium ( 99 Tc), beta emitters, components of nuclear wastes, may increase the dose equivalent to members of the public. Data used by ICRP show that there is relatively little information on Te and Se biokinetics at different physiologic stages. Retention was almost equivalent for young, male adult and pregnant rat. Selenium was concentrated in the testis, the kidneys, the liver and the spleen as technetium was in the skin, the thyroid and the kidneys. The biological half-time for Se and Te was respectively 20 and 41 days for pregnant rats, 33 and 15 days for young rats. Placental transfer per one fetus was 0.56% of the initial activity for Te and 1.27% for Se. These data point out the eventually high doses delivered to the skin for Te and to the testis for Se. They may be taken into consideration in estimating risk by humans at different stages of life [fr

Biokinetics of a transuranic (238PU) and a rare earth element (152Eu) in the lobster (Homarus gammarus): transfer mechanisms (accumulation and detoxification) in organs and at the cellular level

International Nuclear Information System (INIS)

Tocquet, N.

1995-01-01

The work presented here is an experimental investigation of the biokinetics of transfer of a transuranic and a rare earth element ( 238 Pu and 152 Eu) in the lobster Homarus gammarus. The study of 238 Pu biokinetics forms part of a wider framework of research concerning the transfer of transuranic elements in marine species, while the study of 152 Eu is carried out with a view to supporting the analogy between the behaviour of transuranics and rare earths in living organisms. Exactly the same experimental protocol, based on techniques from various disciplines (biology, biochemistry and metrology), was used to Investigate the biokinetics of transfer of these two radionuclides. The Individual lobsters were radiolabelled by means of one-shot or chronic ingestion of spiked meals. As the first approach, the kinetics and transfer mechanisms were studied In whole animal samples and in different organs distinct series of pathways through the different organs were identified in the case of both radionuclides, being mainly linked to digestive processes induced by the meal as well as the transport function of hemo-lymph in this way, the Important role of the digestive gland was picked out, with two of four cellular types displaying a successive involvement In the fixation and then the retention of the studied radionuclides. As a corroborative approach, the digestive gland was subjected to a more detailed investigation with the aim of describing the mechanisms of Incorporation and elucidating transfer processes at the cellular and molecular levels. 238 Pu is preferentially partitioned into the cytosol, where it is associated with various constituents such as ferritin (iron-storing protein). 152 Eu is more diffusely distributed in the hepato-pancreatic cells, while the lysosomes appear to play a more important role during transfer. The results obtained in this study, both on the macroscopic scale (i.e. the whole animal and different organs) as well as the cellular and molecular

Identification of nevadensin as an important herb-based constituent inhibiting estragole bioactivation and physiology-based biokinetic modeling of its possible in vivo effect

International Nuclear Information System (INIS)

Alhusainy, W.; Paini, A.; Punt, A.; Louisse, J.; Spenkelink, A.; Vervoort, J.; Delatour, T.; Scholz, G.; Schilter, B.; Adams, T.; Bladeren, P.J. van; Rietjens, I.M.C.M.

2010-01-01

Estragole is a natural constituent of several herbs and spices including sweet basil. In rodent bioassays, estragole induces hepatomas, an effect ascribed to estragole bioactivation to 1'-sulfooxyestragole resulting in DNA adduct formation. The present paper identifies nevadensin as a basil constituent able to inhibit DNA adduct formation in rat hepatocytes exposed to the proximate carcinogen 1'-hydroxyestragole and nevadensin. This inhibition occurs at the level of sulfotransferase (SULT)-mediated bioactivation of 1'-hydroxyestragole. The Ki for SULT inhibition by nevadensin was 4 nM in male rat and human liver fractions. Furthermore, nevadensin up to 20 μM did not inhibit 1'-hydroxyestragole detoxification by glucuronidation and oxidation. The inhibition of SULT by nevadensin was incorporated into the recently developed physiologically based biokinetic (PBBK) rat and human models for estragole bioactivation and detoxification. The results predict that co-administration of estragole at a level inducing hepatic tumors in vivo (50 mg/kg bw) with nevadensin at a molar ratio of 0.06, representing the ratio of their occurrence in basil, results in almost 100% inhibition of the ultimate carcinogen 1'-sulfooxyestragole when assuming 100% uptake of nevadensin. Assuming 1% uptake, inhibition would still amount to more than 83%. Altogether these data point at a nevadensin-mediated inhibition of the formation of the ultimate carcinogenic metabolite of estragole, without reducing the capacity to detoxify 1'-hydroxyestragole via glucuronidation or oxidation. These data also point at a potential reduction of the cancer risk when estragole exposure occurs within a food matrix containing SULT inhibitors compared to what is observed upon exposure to pure estragole.

Bioaccessibility of Pb from ammunition in game meat is affected by cooking treatment.

Directory of Open Access Journals (Sweden)

Rafael Mateo

Full Text Available BACKGROUND: The presence of lead (Pb ammunition residues in game meat has been widely documented, yet little information exists regarding the bioaccessibility of this Pb contamination. We study how cooking treatment (recipe can affect Pb bioaccessibility in meat of animals hunted with Pb ammunition. METHODOLOGY/PRINCIPAL FINDINGS: We used an in vitro gastrointestinal simulation to study bioaccessibility. The simulation was applied to meat from red-legged partridge (Alectoris rufa hunted with Pb shot pellets and cooked using various traditional Spanish game recipes involving wine or vinegar. Total Pb concentrations in the meat were higher in samples with visible Pb ammunition by X-ray (mean±SE: 3.29±1.12 µg/g w.w. than in samples without this evidence (1.28±0.61 µg/g. The percentage of Pb that was bioaccessible within the simulated intestine phase was far higher in meat cooked with vinegar (6.75% and wine (4.51% than in uncooked meat (0.7%. Risk assessment simulations using our results transformed to bioavailability and the Integrated Exposure Uptake Biokinetic model (IEUBK; US EPA show that the use of wine instead of vinegar in cooking recipes may reduce the percentage of children that would be expected to have >10 µg/dl of Pb in blood from 2.08% to 0.26% when game meat represents 50% of the meat in diet. CONCLUSIONS/SIGNIFICANCE: Lead from ammunition in game meat is more bioaccessible after cooking, especially when using highly acidic recipes. These results are important because existing theoretical models regarding Pb uptake and subsequent risk in humans should take such factors into account.

Different biokinetics of nanomedicines linking to their toxicity; an overview

Directory of Open Access Journals (Sweden)

Abdollahi Mohammad

2013-02-01

Full Text Available Abstract In spite of the extreme rise to the knowledge of nanotechnology in pharmaceutical sciences, there are currently limited experimental works studying the interactions between nanoparticles (NPs and the biological system. Adjustment of size and surface area plays the main role in the reaction between NPs and cells leading to their increased entrance into cells through skin, gastrointestinal and respiratory system. Moreover, change in physicochemical reactivity of NPs causes them to interact with circulatory and cellular proteins differentially leading to the altered parameters of their biokinetics, including adsorption, distribution, translocation, transformation, and elimination. A direct relationship between the surface area, reactive oxygen species generating capability, and proinflammatory effects of NPs have been found in respiratory tract toxicity. Additionally, complement-mediated hypersensitivity reactions to liposomes and other lipid-based nanodrugs have been well defined. Inhalation studies of some NPs have confirmed the translocation of inhaled materials to extra pulmonary organs such as central nervous system (CNS via olfactory neurons and induction of inflammatory response. Injectable uncoated NPs have a tendency to remain on the injection site while the poly ethanol glycol (PEG-coated NPs can be notably drained from the injection site to get as far as the lymph nodes where they accumulate. This confirms the existence of channels within the extracellular matrix for NPs to move along. Furthermore, induction of DNA strand breaks and formation of micronuclei have been recorded for exposure to some NPs such as single-walled carbon nanotubes. In the recent years, most of the studies have simply outlined better efficacy of nanodrugs, but few discussed their possible toxic reactions specially if used chronically. Therefore, we emphasize that this part of the nanoscience must not be undermined and toxicologists must be sensitive to

DETERMINATION OF ACTIVATED SLUDGE MODEL ASDM PARAMETERS FOR WASTE WATER TREATMENT PLANT OPERATING IN THE SEQUENTIAL–FLOW TECHNOLOGY

Directory of Open Access Journals (Sweden)

Dariusz Zdebik

2015-01-01

Full Text Available This paper presents a method for calibration of activated sludge model with the use of computer program BioWin. Computer scheme has been developed on the basis of waste water treatment plant operating in the sequential – flow technology. For calibration of the activated sludge model data of influent and treated effluent from the existing object were used. As a result of conducted analysis was a change in biokinetic model and kinetic parameters parameters of wastewater treatment facilities. The presented method of study of the selected parameters impact on the activated sludge biokinetic model (including autotrophs maximum growth rate, the share of organic slurry in suspension general operational, efficiency secondary settling tanks can be used for conducting simulation studies of other treatment plants.

The STATFLUX code: a statistical method for calculation of flow and set of parameters, based on the Multiple-Compartment Biokinetical Model

Science.gov (United States)

Garcia, F.; Mesa, J.; Arruda-Neto, J. D. T.; Helene, O.; Vanin, V.; Milian, F.; Deppman, A.; Rodrigues, T. E.; Rodriguez, O.

2007-03-01

radioactive substances, through environmental pathways, is very important for radiological protection of populations. One such pathway, associated with the food chain, is the grass-animal-man sequence. The distribution of trace elements in humans and laboratory animals has been intensively studied over the past 60 years [R.C. Pendlenton, C.W. Mays, R.D. Lloyd, A.L. Brooks, Differential accumulation of iodine-131 from local fallout in people and milk, Health Phys. 9 (1963) 1253-1262]. In addition, investigations on the incidence of cancer in humans, and a possible causal relationship to radioactive fallout, have been undertaken [E.S. Weiss, M.L. Rallison, W.T. London, W.T. Carlyle Thompson, Thyroid nodularity in southwestern Utah school children exposed to fallout radiation, Amer. J. Public Health 61 (1971) 241-249; M.L. Rallison, B.M. Dobyns, F.R. Keating, J.E. Rall, F.H. Tyler, Thyroid diseases in children, Amer. J. Med. 56 (1974) 457-463; J.L. Lyon, M.R. Klauber, J.W. Gardner, K.S. Udall, Childhood leukemia associated with fallout from nuclear testing, N. Engl. J. Med. 300 (1979) 397-402]. From the pathways of entry of radionuclides in the human (or animal) body, ingestion is the most important because it is closely related to life-long alimentary (or dietary) habits. Those radionuclides which are able to enter the living cells by either metabolic or other processes give rise to localized doses which can be very high. The evaluation of these internally localized doses is of paramount importance for the assessment of radiobiological risks and radiological protection. The time behavior of trace concentration in organs is the principal input for prediction of internal doses after acute or chronic exposure. The General Multiple-Compartment Model (GMCM) is the powerful and more accepted method for biokinetical studies, which allows the calculation of concentration of trace elements in organs as a function of time, when the flow parameters of the model are known. However, few

Evaluating Alternate Biokinetic Models for Trace Pollutant Cometabolism

DEFF Research Database (Denmark)

Liu, Li; Binning, Philip John; Smets, Barth F.

2015-01-01

Mathematical models of cometabolic biodegradation kinetics can improve our understanding of the relevant microbial reactions and allow us to design in situ or in-reactor applications of cometabolic bioremediation. A variety of models are available, but their ability to describe experimental data...

Dosimetric contribution of the organs of the I123, I124 and I131 bio-kinetics in the dose estimate for euthyroid adults

International Nuclear Information System (INIS)

Vasquez, A. M.; Rojas, A. R.; Castillo, D. C.; Idrogo, C. J.; Flores, U. H.

2011-10-01

Using the formalism MIRD and the representation of Crysty-Eckerman for the thyroid adult, is demonstrated that the dosimetric contributions of source organs of the biokinetics of the radiopharmaceuticals I 123 , I 124 and I 131 (iodine) are not significant in the dose estimate. Therefore, the total absorbed dose by the gland is its auto-dose. Equally, the reported results do not present significant differences to the results found by the Marinelli scheme (auto-dose) for the thyroid represented by a sphere of 20 grams. (Author)

Plutonium 238/239 Decorporation Model

Science.gov (United States)

2014-10-01

4. Transfer Coefficients for the DTPA Biokinetic Model (Breustedt 2009) ...................... 25 Table 5. Decay Properties of Pu-238 and Pu-239...volume 2), cesium-137 (volume 3), F. tularensis (volume 4), sulfur mustard (volume 5), americium-241 (volume 6), Y. pestis (volume 7), botulinum ... toxin (volume 8), plutonium-238/239 (volume 9) and vesicants (volume 10, an expansion on volume 5). This paper presents an inhalation exposure model for

DOSE210, A Semi-empirical Model for Prediction of Organ Distribution and Radiation Doses from Long Term Exposure to 210Pb and 210Po

International Nuclear Information System (INIS)

Salmon, P.L.; Bondarenko, O.A.; Henshaw, D.L.

1999-01-01

The DOSE210 model is an internal dosimetric model for 210 Pb and 210 Po which is based on current ICRP generic models. It is constrained and validated by reference to up-to-date published biokinetic data for both nuclides. The model has been validated primarily in regard to the relation between levels of chronic lifetime intake and organ concentrations of 210 Pb and 210 Po. To this end some adjustments to current ICRP biokinetic parameters have been made. The most substantial changes have been made to bone surface biokinetics of 210 Pb and 210 Po to reflect recent experimental studies on the microdistribution and radioactive equilibrium of these nuclides in bone, as well as measurements in biopsied human red bone marrow. An important dosimetric prediction of DOSE210 is a substantially lower dose to skeletal tissues from internal 210 Pb and 210 Po than that predicted by the current ICRP model. The most significant dose component predicted from lifetime environmental exposure to 210 Pb and 210 Po is the alpha dose to liver and kidney in infancy. Recycling of historic intakes of 210 Pb in the adult, principally from bone, is calculated to account for 22% of 210 Pb present in the plasma. (author)

Developing a physiologically based approach for modeling plutonium decorporation therapy with DTPA.

Science.gov (United States)

Kastl, Manuel; Giussani, Augusto; Blanchardon, Eric; Breustedt, Bastian; Fritsch, Paul; Hoeschen, Christoph; Lopez, Maria Antonia

2014-11-01

To develop a physiologically based compartmental approach for modeling plutonium decorporation therapy with the chelating agent Diethylenetriaminepentaacetic acid (Ca-DTPA/Zn-DTPA). Model calculations were performed using the software package SAAM II (©The Epsilon Group, Charlottesville, Virginia, USA). The Luciani/Polig compartmental model with age-dependent description of the bone recycling processes was used for the biokinetics of plutonium. The Luciani/Polig model was slightly modified in order to account for the speciation of plutonium in blood and for the different affinities for DTPA of the present chemical species. The introduction of two separate blood compartments, describing low-molecular-weight complexes of plutonium (Pu-LW) and transferrin-bound plutonium (Pu-Tf), respectively, and one additional compartment describing plutonium in the interstitial fluids was performed successfully. The next step of the work is the modeling of the chelation process, coupling the physiologically modified structure with the biokinetic model for DTPA. RESULTS of animal studies performed under controlled conditions will enable to better understand the principles of the involved mechanisms.

The models of internal dose calculation in ICRP

International Nuclear Information System (INIS)

Nakano, Takashi

1995-01-01

There are a lot discussions about internal dose calculation in ICRP. Many efforts are devoted to improvement in models and parameters. In this report, we discuss what kind of models and parameters are used in ICRP. Models are divided into two parts, the dosimetric model and biokinetic model. The former is a mathematical phantom model, and it is mainly developed in ORNL. The results are used in many researchers. The latter is a compartment model and it has a difficulty to decide the parameter values. They are not easy to estimate because of their age dependency. ICRP officially sets values at ages of 3 month, 1 year, 5 year, 10 year, 15 year and adult, and recommends to get values among ages by linear age interpolate. But it is very difficult to solve the basic equation with these values, so we calculate by use of computers. However, it has complex shame and needs long CPU time. We should make approximated equations. The parameter values include much uncertainty because of less experimental data, especially for a child. And these models and parameter values are for Caucasian. We should inquire whether they could correctly describe other than Caucasian. The body size affects the values of calculated SAF, and the differences of metabolism change the biokinetic pattern. (author)

Radionuclide decorporation: matching the biokinetics of actinides by transdermal delivery of pro-chelators.

Science.gov (United States)

Zhang, Yong; Sadgrove, Matthew P; Mumper, Russell J; Jay, Michael

2013-10-01

The threat of nuclear terrorism by the deliberate detonation of a nuclear weapon or radiological dispersion device ("dirty bomb") has made emergency response planning a priority. The only FDA-approved treatments for contamination with isotopes of the transuranic elements Am, Pu, and Cm are the Ca and Zn salts of diethylenetriaminepentaacetic acid (DTPA). These injectable products are not well suited for use in a mass contamination scenario as they require skilled professionals for their administration and are rapidly cleared from the circulation. To overcome the mismatch in the pharmacokinetics of the DTPA and the biokinetics of these transuranic elements, which are slowly released from contamination sites, the penta-ethyl ester of DTPA (C2E5) was prepared and formulated in a nonaqueous gel for transdermal administration. When gels comprised of 40% C2E5, 40-45% Miglyol® 840, and 15-20% ethyl cellulose were spiked with [(14)C]-C2E5 and applied to rat skin; over 60% of the applied dose was absorbed within a 24-h period. Radioactivity was observed in urinary and fecal excretions for over 3 days after removal of the gel. Using an (241)Am wound contamination model, transdermal C2E5 gels were able to enhance total body elimination and reduce the liver and skeletal burden of (241)Am in a dose-dependent manner. The efficacy achieved by a single 1,000 mg/kg dose to contaminated rats was statistically comparable to intravenous Ca-DTPA at 14 mg/kg. The effectiveness of this treatment, favorable sustained release profile of pro-chelators, and ease of administration support its use following radiological emergencies and for its inclusion in the Strategic National Stockpile.

Identification of Biokinetic Models Using the Concept of Extents.

Science.gov (United States)

Mašić, Alma; Srinivasan, Sriniketh; Billeter, Julien; Bonvin, Dominique; Villez, Kris

2017-07-05

The development of a wide array of process technologies to enable the shift from conventional biological wastewater treatment processes to resource recovery systems is matched by an increasing demand for predictive capabilities. Mathematical models are excellent tools to meet this demand. However, obtaining reliable and fit-for-purpose models remains a cumbersome task due to the inherent complexity of biological wastewater treatment processes. In this work, we present a first study in the context of environmental biotechnology that adopts and explores the use of extents as a way to simplify and streamline the dynamic process modeling task. In addition, the extent-based modeling strategy is enhanced by optimal accounting for nonlinear algebraic equilibria and nonlinear measurement equations. Finally, a thorough discussion of our results explains the benefits of extent-based modeling and its potential to turn environmental process modeling into a highly automated task.

99mTc-labeled PSMA inhibitor: Biokinetics and radiation dosimetry in healthy subjects and imaging of prostate cancer tumors in patients.

Science.gov (United States)

Santos-Cuevas, Clara; Davanzo, Jenny; Ferro-Flores, Guillermina; García-Pérez, Francisco O; Ocampo-García, Blanca; Ignacio-Alvarez, Eleazar; Gómez-Argumosa, Edgar; Pedraza-López, Martha

2017-09-01

The prostate-specific membrane antigen (PSMA) is expressed in epithelial cells of the prostate and highly overexpressed in 95% of advanced prostate cancers. The aims of this study was to estimate the biokinetics and dosimetry of 99m Tc-EDDA/HYNIC-iPSMA ( 99m Tc-labeled PSMA inhibitor) in eight healthy subjects and evaluate its usefulness as a tumor-imaging agent in eight prostate cancer patients. 99m Tc-EDDA/HYNIC-iPSMA was obtained from a lyophilized formulation with radiochemical purities >98%, determined by reversed-phase HPLC and ITLC-SG analyses. Whole-body images from eight healthy subjects were acquired at 20min, and at 2, 6 and 24h after 99m Tc-EDDA/HYNIC-iPSMA administration. Regions of interest (ROIs) were drawn around the source organs on each time frame. Each ROI was corrected by background, attenuation, scattered radiation and physical decay. The image sequence was used to extrapolate the 99m Tc-EDDA/HYNIC-iPSMA time-activity curves of each organ to adjust the biokinetic model and calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation doses. In eight prostate cancer patients with histologically confirmed cancer, whole-body SPECT/CT images were obtained at 3h. The blood activity showed a half-life value of 4.98min for the fast component (T 1/2 α=ln2/8.34), 2.49h for the first slow component (T 1/2 β=ln2/0.278), and 9.24h for the second slow component (T 1/2 γ=ln2/0.076). Images from patients showed an average tumor/background ratio of 8.99±3.27 at 3h. The average equivalent doses calculated for a study using 740MBq were 3.80, 7.06, 9.69, 10.70, and 28.80mSv for the breast, spleen, salivary glands, liver, and kidneys respectively, with an effective dose of 3.42±0.78mSv. All the absorbed doses were comparable to those known for most of the 99m Tc studies. 99m Tc-EDDA/HYNIC-iPSMA obtained from kit formulations showed high tumor uptake in

Depth investigation of rapid sand filters for drinking water production reveals strong stratification in nitrification biokinetic behavior

DEFF Research Database (Denmark)

Tatari, Karolina; Smets, Barth F.; Albrechtsen, Hans-Jørgen

2016-01-01

The biokinetic behavior of NH4 + removal was investigated at different depths of a rapid sand filter treating groundwater for drinking water preparation. Filter materials from the top, middle and bottom layers of a full-scale filter were exposed to various controlled NH4 + loadings in a continuous......-flow lab-scale assay. NH4 + removal capacity, estimated from short term loading up-shifts, was at least 10 times higher in the top than in the middle and bottom filter layers, consistent with the stratification of Ammonium Oxidizing Bacteria (AOB). AOB density increased consistently with the NH4 + removal...... rate, indicating their primarily role in nitrification under the imposed experimental conditions. The maximum AOB cell specific NH4 + removal rate observed at the bottom was at least 3 times lower compared to the top and middle layers. Additionally, a significant up-shift capacity (4.6 and 3.5 times...

Decoupling of cadmium biokinetics and metallothionein turnover in a marine polychaete after metal exposure

Energy Technology Data Exchange (ETDEWEB)

Ng, Tania Y.-T. [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong (China); Rainbow, Philip S. [Department of Zoology, Natural History Museum, Cromwell Road, London SW7 5BD (United Kingdom); Amiard-Triquet, Claude; Amiard, Jean-Claude [Universite de Nantes, Faculte de Pharmacie, MMS EA2160, Service d' ecotoxicologie, F-44000 Nantes (France); Wang Wenxiong [Department of Biology, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong (China)], E-mail: wwang@ust.hk

2008-08-11

This study investigated the kinetics of Cd bioaccumulation, detoxification, subcellular distribution, and efflux in the nereid polychaete Perinereis aibuhitensis after Cd pre-exposure. Cd pre-exposure increased the Cd body burden in the worms, but did not affect the overall Cd uptake and efflux rates and metallothionein-like protein (MTLP) concentrations. During short-term exposure to dissolved Cd, Cd in the cytosolic fraction increased after Cd pre-exposure, and this fraction also increased during the Cd efflux period, indicating that the insoluble fraction of Cd was presumably lost at a faster rate than the loss of cytosolic Cd. Even though the MTLP concentration remained comparable after Cd pre-exposure, both the MTLP synthesis rate and the degradation rate increased, thus leading to a high MTLP turnover in the Cd-exposed worms. However, Cd uptake and efflux into different protein size fractions did not follow the patterns of MTLP synthesis and degradation, strongly suggesting that Cd kinetics is decoupled from the MTLP kinetics in the worms. Our study adds to an increasing body of evidence on the complicated relationship between metal biokinetics and MTLP kinetics in different groups of marine invertebrates which have strong contrasts in their metal handling strategies.

Decoupling of cadmium biokinetics and metallothionein turnover in a marine polychaete after metal exposure

International Nuclear Information System (INIS)

Ng, Tania Y.-T.; Rainbow, Philip S.; Amiard-Triquet, Claude; Amiard, Jean-Claude; Wang Wenxiong

2008-01-01

This study investigated the kinetics of Cd bioaccumulation, detoxification, subcellular distribution, and efflux in the nereid polychaete Perinereis aibuhitensis after Cd pre-exposure. Cd pre-exposure increased the Cd body burden in the worms, but did not affect the overall Cd uptake and efflux rates and metallothionein-like protein (MTLP) concentrations. During short-term exposure to dissolved Cd, Cd in the cytosolic fraction increased after Cd pre-exposure, and this fraction also increased during the Cd efflux period, indicating that the insoluble fraction of Cd was presumably lost at a faster rate than the loss of cytosolic Cd. Even though the MTLP concentration remained comparable after Cd pre-exposure, both the MTLP synthesis rate and the degradation rate increased, thus leading to a high MTLP turnover in the Cd-exposed worms. However, Cd uptake and efflux into different protein size fractions did not follow the patterns of MTLP synthesis and degradation, strongly suggesting that Cd kinetics is decoupled from the MTLP kinetics in the worms. Our study adds to an increasing body of evidence on the complicated relationship between metal biokinetics and MTLP kinetics in different groups of marine invertebrates which have strong contrasts in their metal handling strategies

Radiation exposure of the patient in diagnostic nuclear medicine. Experimental studies of the biokinetics of 111In-DTPA-D-Phe1-octreotide, 99mTc-MIBI, 14C-triolein and 14C-urea, and development of dosimetric models

International Nuclear Information System (INIS)

Leide Svegborn, S.

1999-03-01

Biokinetic and dosimetric models for a number of clinically used radiopharmaceuticals, for which information on the radiation dosimetry is scarce, have been produced. On patients undergoing investigations with 111 In-DTPA-D-Phe 1 -octreotide (for diagnosis of neuroendocrine tumours) and 99m Tc-MIBI (for myocardial perfusion imaging), whole body gamma camera scanning was performed several times after administration of the radiopharmaceutical. Total body and organ activity content was determined using the geometric mean of the number of counts in two 180 deg opposed planar images. A thorough investigation of sources influencing the accuracy of the quantification of activity was carried out, showing an overall uncertainty varying from 10% to 30% for organs with a significant uptake and 5% for the whole body. The activity in blood and urine was also measured. 111 In-DTPA-D-Phe 1 -octreotide was predominantly excreted via the kidney-bladder system and a typical investigation with 1200 MBq resulted in an effective dose of 8.4 mSv (0.076 mSv/MBq). 99m Tc-MIBI was to a great extent excreted via the gastrointestinal tract and an investigation with 1200 MBq resulted in an effective dose of 13 mSv (0.011 mSv/MBq). Accelerator mass spectrometry (AMS) was used to investigate the possibility to measure ultra-low activity concentrations of 14 CO 2 , in exhaled air from patients undergoing 14 C-breath tests, with special application to 14 C-triolein (for study of fat malabsorption). AMS was proven to be a useful technique for long-term retention studies of 14 C, and was used together with liquid scintillation counting in an investigation of the biokinetics of 14 C-urea in adult and paediatric patients (for diagnosis of Helicobacter pylori infection in the upper gastrointestinal tract). The effective dose for 14 C-urea was 0.019 mSv/MBq for adults and from 0.041 to 0.019 mSv/MBq for seven- to fourteen -year-old children, resulting in an effective dose of approximately 0.002 mSv per

A multiple-compartment model for biokinetics studies in plants

International Nuclear Information System (INIS)

Garcia, Fermin; Pietrobron, Flavio; Fonseca, Agnes M.F.; Mol, Anderson W.; Rodriguez, Oscar; Guzman, Fernando

2001-01-01

In the present work is used the system of linear equations based in the general Assimakopoulos's GMCM model , for the development of a new method that will determine the flow's parameters and transfer coefficients in plants. The need of mathematical models to quantify the penetration of a trace substance in animals and plants, has often been stressed in the literature. Usually, in radiological environment studies, it is used the mean value of contaminant concentrations on whole or edible part plant body, without taking in account vegetable physiology regularities. In this work concepts and mathematical formulation of a Vegetable Multi-compartment Model (VMCM), taking into account the plant's physiology regularities is presented. The model based in general ideas of the GMCM , and statistical Square Minimum Method STATFLUX is proposed to use in inverse sense: the experimental time dependence of concentration in each compartment, should be input, and the parameters should be determined from this data in a statistical approach. The case of Uranium metabolism is discussed. (author)

Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat; Etudes biocinetique et biologique comparees d'inhalations chroniques et aigues de composes uraniferes chez le rat

Energy Technology Data Exchange (ETDEWEB)

Monleau, M

2005-12-15

Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure. It

BK/TD models for analyzing in vitro impedance data on cytotoxicity.

Science.gov (United States)

Teng, S; Barcellini-Couget, S; Beaudouin, R; Brochot, C; Desousa, G; Rahmani, R; Pery, A R R

2015-06-01

The ban of animal testing has enhanced the development of new in vitro technologies for cosmetics safety assessment. Impedance metrics is one such technology which enables monitoring of cell viability in real time. However, analyzing real time data requires moving from static to dynamic toxicity assessment. In the present study, we built mechanistic biokinetic/toxicodynamic (BK/TD) models to analyze the time course of cell viability in cytotoxicity assay using impedance. These models account for the fate of the tested compounds during the assay. BK/TD models were applied to analyze HepaRG cell viability, after single (48 h) and repeated (4 weeks) exposures to three hepatotoxic compounds (coumarin, isoeugenol and benzophenone-2). The BK/TD models properly fit the data used for their calibration that was obtained for single or repeated exposure. Only for one out of the three compounds, the models calibrated with a single exposure were able to predict repeated exposure data. We therefore recommend the use of long-term exposure in vitro data in order to adequately account for chronic hepatotoxic effects. The models we propose here are capable of being coupled with human biokinetic models in order to relate dose exposure and human hepatotoxicity. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Reduced risk estimations after remediation of lead (Pb) in drinking water at two US school districts.

Science.gov (United States)

Triantafyllidou, Simoni; Le, Trung; Gallagher, Daniel; Edwards, Marc

2014-01-01

The risk of students to develop elevated blood lead from drinking water consumption at schools was assessed, which is a different approach from predictions of geometric mean blood lead levels. Measured water lead levels (WLLs) from 63 elementary schools in Seattle and 601 elementary schools in Los Angeles were acquired before and after voluntary remediation of water lead contamination problems. Combined exposures to measured school WLLs (first-draw and flushed, 50% of water consumption) and home WLLs (50% of water consumption) were used as inputs to the Integrated Exposure Uptake Biokinetic (IEUBK) model for each school. In Seattle an average 11.2% of students were predicted to exceed a blood lead threshold of 5 μg/dL across 63 schools pre-remediation, but predicted risks at individual schools varied (7% risk of exceedance at a "low exposure school", 11% risk at a "typical exposure school", and 31% risk at a "high exposure school"). Addition of water filters and removal of lead plumbing lowered school WLL inputs to the model, and reduced the predicted risk output to 4.8% on average for Seattle elementary students across all 63 schools. The remnant post-remediation risk was attributable to other assumed background lead sources in the model (air, soil, dust, diet and home WLLs), with school WLLs practically eliminated as a health threat. Los Angeles schools instead instituted a flushing program which was assumed to eliminate first-draw WLLs as inputs to the model. With assumed benefits of remedial flushing, the predicted average risk of students to exceed a BLL threshold of 5 μg/dL dropped from 8.6% to 6.0% across 601 schools. In an era with increasingly stringent public health goals (e.g., reduction of blood lead safety threshold from 10 to 5 μg/dL), quantifiable health benefits to students were predicted after water lead remediation at two large US school systems. © 2013.

Compared biokinetic and biological studies of chronic and acute inhalations of uranium compounds in the rat; Etudes biocinetique et biologique comparees d'inhalations chroniques et aigues de composes uraniferes chez le rat

Energy Technology Data Exchange (ETDEWEB)

Monleau, M

2005-12-15

Uranium is a natural, radioactive heavy metal, widely used in the nuclear industry in various chemical and isotopic forms. Its use in the fuel cycle involves the risk of radiological exposure for the workers, mainly via the inhalation of uranium particles. According to the workplace configuration, uranium contaminations can be acute or repeated, involve various chemical forms and different levels of enrichment, as well as involving one or several components. The dosimetric concepts and models available for workers' radiological protection, as well as most of the studies of the biological effects, correspond to acute exposure situations. Moreover the processes leading to pathological effects are little known in vivo. In this context, the main question is to know whether exposures due to repeated inhalation by rats induce the element kinetics and toxicity, which may be different from those observed after an acute exposure. In this study, comparison of the experimental and theoretical biokinetics of an insoluble uranium repeatedly inhaled over three weeks shows that a chronic contamination is correctly modelled, except for bone retention, by the sum of acute, successive and independent incorporations. Moreover, the kinetics of a soluble uranium inhaled irregularly can be modified by previous repeated exposure to an insoluble uranium. In certain cases therefore, exposure to uranium could modify its biokinetics during later exposures. At a toxicological level, the study demonstrates that the uranium particles inhaled repeatedly induce behavioural disruptions and genotoxic effects resulting in various sorts of DNA damage, in several cell types and certainly depending on the quantity inhaled. Exposures involving several uraniferous components produce a synergy effect. Moreover, repeated inhalations worsen the genotoxic effects in comparison to an acute exposure. This work demonstrates the importance of not ignoring the effects of the repetition of uranium exposure

Influence of zinc on the biokinetics of Zn-65 and hepatic trace elements of ethanol treated rats

International Nuclear Information System (INIS)

Dhawan, D.K.; Pathak, A.; Pathak, R.; Mahmood, A.

2002-01-01

Influence of zinc on the biokinetics of 65 Zn and hepatic trace elements of ethanol treated rats. The effect of zinc on the biokinetics of 65 Zn in liver and whole body and its relation to the hepatic levels of different elements was evaluated in male wistar rats under alcoholic conditions. The rats were segregated into four treatment groups viz., normal control, ethanol treated, zinc treated and combined zinc+ethanol treated. Animals were fed 3ml of 30% ethanol orally daily and zinc in the form of zinc sulfate (ZnSo 4 7H 2 O) was administrated to rats at a dose level of 227mg/L mixed in their drinking water for a total duration of 2 months. Whole body counting studies indicated that the Tb 1 i.e., the faster elimination of the radiotracer. On the contrary, Tb 2 i.e., the slower component was increased significantly following ethanol treatment. Percent uptake values of 65 Zn were found to be increased in liver, intestine, muscle and kidney and decreased in bone under alcoholic conditions. A significant elevation was noticed in in vitro uptake 65 Zn in ethanol treated animals. In the above said conditions, the values were reverted back to within normal limits upon zinc supplementation to these ethanol intoxicated animals, except in the case of in vitro 65 Zn uptake in liver where the uptake was further increased upon combined treatment. A significant decrease in zinc contents was noticed in ethanol treated rats, which however were raised to normal levels upon zinc supplementation. Copper levels, on the other hand, were found to be significantly enhanced in both ethanol fed and combined ethanol+zinc supplemented animals. Calcium levels were found to e significantly decreased in both ethanol and zinc treated rats, which however were further reduced upon zinc supplementation to ethanol fed rats. However, no significant change was observed in the concentrations of sodium and potassium in any of the treatment groups. Therefore, zinc appears to play a protective role by

Dosimetric evaluation in organs of the Tc{sup 99m}, I{sup 123} bio-kinetics to estimate dose in thyroid children 1 and 5 years; Evaluacion dosimetrica en organos de la biocinetica del Tc{sup 99m}, I{sup 123} para estimar dosis en tiroides ninos 1 y 5 anos

Energy Technology Data Exchange (ETDEWEB)

Vasquez, A. M.; Quispe, R.; Vasquez, D. J.; Rocha, M. D.; Morales, N. R.; Marin, R. K. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Ciudad Universitaria, Trujillo (Peru); Zelada, A. L., E-mail: marvva@hotmail.com [Universidad Cesar Vallejo, Grupo de Fisica Medica, Av. Larco s/n, Trujillo (Peru)

2012-10-15

Using the formalism MIRD and the representation of Cristy-Eckerman for the thyroid in children of 1 and 5 years, is demonstrated that the dosimetric contribution of the organs of I{sup 123} (iodure) bio-kinetics is not significant in the dose estimate. The total dose absorbed by the gland is its auto dose. The dosimetric contribution of the organs source of the Tc{sup 99m} (pertechnetate) bio-kinetics in the gland is significant in the dose estimate like to be ignored. The reported results for the iodure are not significantly different to the found for the Marinelli scheme (auto-dose) for thyroid represented by a sphere of 1,78 and 3,45 grams. (Author)

Biokinetic data of various radioactive cationic molecules. An attempt at evaluation of significant chemical properties of myotropic agents

International Nuclear Information System (INIS)

Munze, R.; Kretzschmar, M.; Syhre, R.; Kampf, G.; Klotzer, D.; Guthert, I.; Bergmann, R.

1986-01-01

Research on lipophilic cationic radiopharmaceuticals has been established as an important field of modern radiopharmacology and experimental nuclear medicine. The present state is best demonstrated by scintigrams obtained with Tc-TBI (TBI = tertiary butylisocyanide). These images clearly reveal the advantage of these compounds, namely high information density, which resulted in an excellent delineation of activity accumulations, as well as the lasting drawback represented by partial overlapping of the right lobe of the liver in a certain region of the inferior wall of the heart. Current research is mainly focused on overcoming this disadvantage by synthesizing appropriate compounds with higher heart/liver uptake in man. A more sophisticated rationale than cationic charge and lipophilicity would be much appreciated. This paper deals with possible correlations between the biodistribution and biokinetics of such compounds, though not exclusively for technetium cations, and their important chemical properties such as composition, size, and polar regions within the lipophilic molecule, which are considered significant parameters

Age-specific models for evaluating dose and risk from internal exposures to radionuclides: Report of current work of the Metabolism and Dosimetry Research Group, July 1, 1985-June 30, 1987

International Nuclear Information System (INIS)

Leggett, R.W.; Warren, B.P.

1987-09-01

A projection of the health risk to a population internally exposed to a radionuclide requires explicit or implicit use of demographic, biokinetic, dosimetric, and dose-response models. Exposure guidelines have been based on models for a reference adult with a fixed life span. In this report, we describe recent efforts to develop a comprehensive methodology for estimation of radiogenic risk to individuals and to heterogeneous populations. Emphasis is on age-dependent biokinetics and dosimetry for internal emitters, but consideration also is given to conversion of age-specific doses to estimates of risk using realistic, site-specific demographic models and best available age-specific dose-response functions. We discuss how the methods described here may also improve estimates for the reference adult usually considered in radiation protection. 159 refs

Age-specific models for evaluating dose and risk from internal exposures to radionuclides: Report of current work of the Metabolism and Dosimetry Research Group, July 1, 1985-June 30, 1987

Energy Technology Data Exchange (ETDEWEB)

Leggett, R.W.; Warren, B.P. (eds.)

1987-09-01

A projection of the health risk to a population internally exposed to a radionuclide requires explicit or implicit use of demographic, biokinetic, dosimetric, and dose-response models. Exposure guidelines have been based on models for a reference adult with a fixed life span. In this report, we describe recent efforts to develop a comprehensive methodology for estimation of radiogenic risk to individuals and to heterogeneous populations. Emphasis is on age-dependent biokinetics and dosimetry for internal emitters, but consideration also is given to conversion of age-specific doses to estimates of risk using realistic, site-specific demographic models and best available age-specific dose-response functions. We discuss how the methods described here may also improve estimates for the reference adult usually considered in radiation protection. 159 refs.

Modelling of green microalgal growth and algal storage processes using wastewater resources

DEFF Research Database (Denmark)

Wágner, Dorottya Sarolta; Plósz, Benedek G.; Valverde Pérez, Borja

2017-01-01

Recent research focuses on the recovery of nutrients, water and energy from wastewater. Microalgal cultivation on wastewater resources is considered as a more sustainable means to produce fertilizers or biofuels. Innovative systems that incorporate microalgal cultivation into conventional wastewa...... have been developed according to the activated sludge modelling (ASM) framework to facilitate the integration with existing modelling frameworks in water treatment. This chapter presents in detail the recently developed ASM-A biokinetic green microalgal process model. The model includes...

A computational code for resolution of general compartment models applied to internal dosimetry

International Nuclear Information System (INIS)

Claro, Thiago R.; Todo, Alberto S.

2011-01-01

The dose resulting from internal contamination can be estimated with the use of biokinetic models combined with experimental results obtained from bio analysis and the knowledge of the incorporation time. The biokinetics models can be represented by a set of compartments expressing the transportation, retention and elimination of radionuclides from the body. The ICRP publications, number 66, 78 and 100, present compartmental models for the respiratory tract, gastrointestinal tract and for systemic distribution for an array of radionuclides of interest for the radiological protection. The objective of this work is to develop a computational code for designing, visualization and resolution of compartmental models of any nature. There are available four different techniques for the resolution of system of differential equations, including semi-analytical and numerical methods. The software was developed in C≠ programming, using a Microsoft Access database and XML standards for file exchange with other applications. Compartmental models for uranium, thorium and iodine radionuclides were generated for the validation of the CBT software. The models were subsequently solved by SSID software and the results compared with the values published in the issue 78 of ICRP. In all cases the system is in accordance with the values published by ICRP. (author)

A computational code for resolution of general compartment models applied to internal dosimetry

Energy Technology Data Exchange (ETDEWEB)

Claro, Thiago R.; Todo, Alberto S., E-mail: claro@usp.br, E-mail: astodo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2011-07-01

The dose resulting from internal contamination can be estimated with the use of biokinetic models combined with experimental results obtained from bio analysis and the knowledge of the incorporation time. The biokinetics models can be represented by a set of compartments expressing the transportation, retention and elimination of radionuclides from the body. The ICRP publications, number 66, 78 and 100, present compartmental models for the respiratory tract, gastrointestinal tract and for systemic distribution for an array of radionuclides of interest for the radiological protection. The objective of this work is to develop a computational code for designing, visualization and resolution of compartmental models of any nature. There are available four different techniques for the resolution of system of differential equations, including semi-analytical and numerical methods. The software was developed in C{ne} programming, using a Microsoft Access database and XML standards for file exchange with other applications. Compartmental models for uranium, thorium and iodine radionuclides were generated for the validation of the CBT software. The models were subsequently solved by SSID software and the results compared with the values published in the issue 78 of ICRP. In all cases the system is in accordance with the values published by ICRP. (author)

Lead Bioaccumulation Factor of Cockle Shell (Anadara granosa) Base on Biokinetic Study that Used Radiotracer 210Pb

International Nuclear Information System (INIS)

Heru Umbara; Heny Suseno

2007-01-01

Lead is kind of hazardous heavy metal to human health and the concentration in the coastal environment should be monitored continuously because lead could be accumulated by marine biota. One of the monitoring techniques is bio indicator. Anadara granosa is a marine biota which spread in almost all Indonesian coastal, life in the bottom and mud sandy environment in the depth of until 4 meter and relatively still. Base on the book of environmental equilibrium balance DKI Jakarta, Anadara granosa is a macrozobenthos in Jakarta bay which have second highest density after Donax or with density of 14 individual per meter square. Base on the environmental equilibrium balance from 26 locations, 22 locations can be found Anadara granosa so this mollusk could be used for bio indicator. The objective of research for bioaccumulation that use 210 Pb as a tracer is to find bio indicator base on biokinetic process which include concentration factor, uptake and depuration processes and biology half life. The result shows that Anadara granosa could be use as a lead bio indicator in Jakarta bay. (author)

Energy use and carbon footprints differ dramatically for diverse wastewater-derived carbonaceous substrates: An integrated exploration of biokinetics and life-cycle assessment.

Science.gov (United States)

Li, Yanbo; Wang, Xu; Butler, David; Liu, Junxin; Qu, Jiuhui

2017-03-21

Energy neutrality and reduction of carbon emissions are significant challenges to the enhanced sustainability of wastewater treatment plants (WWTPs). Harvesting energy from wastewater carbonaceous substrates can offset energy demands and enable net power generation; yet, there is limited research about how carbonaceous substrates influence energy and carbon implications of WWTPs with integrated energy recovery at systems-level. Consequently, this research uses biokinetics modelling and life cycle assessment philology to explore this notion, by tracing and assessing the quantitative flows of energy embodied or captured, and by exploring the carbon footprint throughout an energy-intensive activated sludge process with integrated energy recovery facilities. The results indicate that energy use and carbon footprint per cubic meter of wastewater treated, varies markedly with the carbon substrate. Compared with systems driven with proteins, carbohydrates or other short-chain fatty acids, systems fed with acetic acid realized energy neutrality with maximal net gain of power from methane combustion (0.198 kWh) and incineration of residual biosolids (0.153 kWh); and also achieved a negative carbon footprint (72.6 g CO 2 ). The findings from this work help us to better understand and develop new technical schemes for improving the energy efficiency of WWTPs by repurposing the stream of carbon substrates across systems.

Radiation exposure of the patient in diagnostic nuclear medicine. Experimental studies of the biokinetics of {sup 111}In-DTPA-D-Phe{sup 1}-octreotide, {sup 99m}Tc-MIBI, {sup 14}C-triolein and {sup 14}C-urea, and development of dosimetric models

Energy Technology Data Exchange (ETDEWEB)

Leide Svegborn, S

1999-03-01

Biokinetic and dosimetric models for a number of clinically used radiopharmaceuticals, for which information on the radiation dosimetry is scarce, have been produced. On patients undergoing investigations with {sup 111}In-DTPA-D-Phe{sup 1}-octreotide (for diagnosis of neuroendocrine tumours) and {sup 99m}Tc-MIBI (for myocardial perfusion imaging), whole body gamma camera scanning was performed several times after administration of the radiopharmaceutical. Total body and organ activity content was determined using the geometric mean of the number of counts in two 180 deg opposed planar images. A thorough investigation of sources influencing the accuracy of the quantification of activity was carried out, showing an overall uncertainty varying from 10% to 30% for organs with a significant uptake and 5% for the whole body. The activity in blood and urine was also measured. {sup 111}In-DTPA-D-Phe{sup 1}-octreotide was predominantly excreted via the kidney-bladder system and a typical investigation with 1200 MBq resulted in an effective dose of 8.4 mSv (0.076 mSv/MBq). {sup 99m}Tc-MIBI was to a great extent excreted via the gastrointestinal tract and an investigation with 1200 MBq resulted in an effective dose of 13 mSv (0.011 mSv/MBq). Accelerator mass spectrometry (AMS) was used to investigate the possibility to measure ultra-low activity concentrations of {sup 14}CO{sub 2}, in exhaled air from patients undergoing {sup 14}C-breath tests, with special application to {sup 14}C-triolein (for study of fat malabsorption). AMS was proven to be a useful technique for long-term retention studies of {sup 14}C, and was used together with liquid scintillation counting in an investigation of the biokinetics of {sup 14}C-urea in adult and paediatric patients (for diagnosis of Helicobacter pylori infection in the upper gastrointestinal tract). The effective dose for {sup 14}C-urea was 0.019 mSv/MBq for adults and from 0.041 to 0.019 mSv/MBq for seven- to fourteen -year-old children

Uniquely high turnover of nickel in contaminated oysters Crassostrea hongkongensis: Biokinetics and subcellular distribution.

Science.gov (United States)

Yin, Qijun; Wang, Wen-Xiong

2018-01-01

Despite the environmental concerns regarding nickel (Ni) especially in China, it has received little attention in aquatic animals due to its comparatively weak toxicity. In the present study, we explored the bioaccumulation, biokinetics, and subcellular distribution of Ni in an estuarine oyster Crassostrea hongkongensis. We demonstrated that Ni represented a new pattern of bioaccumulation in oysters characterized by rapid elimination and low dissolved uptake. The waterborne uptake rate constant and dietary assimilation efficiency were 0.036L/g/h and 28%, respectively, and dissolved uptake was the predominant exposure route. The efflux rate constant was positively related to tissue Ni concentration, with the highest efflux of 0.155d -1 . Such high elimination resulted in a high Ni turnover and steady-state condition reached rapidly, as shown with a 4-week waterborne exposure experiment at different Ni concentrations. Ni in oysters was mainly sequestered in metallothionein-like protein (MTLP), metal-rich granule, and cellular debris. MTLP was the most important binding fraction during accumulation and depuration, and played a dynamic role leading to rapid Ni elimination. Pre-exposure to Ni significantly reduced the dissolved uptake, probably accompanied by depressed filtration activity. Overall, the high turnover and regulation of Ni in oysters were achieved by enhanced efflux, suppressed uptake, and sequestration of most Ni into the detoxified pool. Copyright © 2017 Elsevier B.V. All rights reserved.

Investigations by gamma spectrometry and histoaudiography of the biokinetics of colloidal 232ThO2 ('Thorotrast')

International Nuclear Information System (INIS)

Foell, U.

1978-01-01

Experiments were carried out in mice in order to determine activity ratios and distribution kinetics of ThO 2 and its decay products. The data will be used as a basic for dose calculations. In supplementary investigations, the microdistribution, localisation, and quantitative enrichment of thorotrast were determined in order to provide a basis for microdosimetric evaluation of late thorotrast lesions. The radioactive colloid was injected intravenously into the tail vein of the animals (25 to 250 μl). Whole-body activity was measured at regular intervals. The animals were killed at different times after incorporation, and their livers, spleens, and skeleton without bone marrow were investigated by gammy spectrometry and histoautoradiography. With the findings obtained for the macroscopic distribution of colloid 232 ThO 2 and its decay products on the cellular level as a function of the duration of thorotrast storage, the mean radiation exposure of RHS organs can be determined and at least the order of magnitude of the local dose can be estimated. It will require long-term animal experiments to determine the biological effects of thorotrast incorporation and correlate them with the results of these dose calculations on the basis of the studies on thorotrast biokinetics. (orig./MG) [de

Mixing characterisation of full-scale membrane bioreactors: CFD modelling with experimental validation.

Science.gov (United States)

Brannock, M; Wang, Y; Leslie, G

2010-05-01

Membrane Bioreactors (MBRs) have been successfully used in aerobic biological wastewater treatment to solve the perennial problem of effective solids-liquid separation. The optimisation of MBRs requires knowledge of the membrane fouling, biokinetics and mixing. However, research has mainly concentrated on the fouling and biokinetics (Ng and Kim, 2007). Current methods of design for a desired flow regime within MBRs are largely based on assumptions (e.g. complete mixing of tanks) and empirical techniques (e.g. specific mixing energy). However, it is difficult to predict how sludge rheology and vessel design in full-scale installations affects hydrodynamics, hence overall performance. Computational Fluid Dynamics (CFD) provides a method for prediction of how vessel features and mixing energy usage affect the hydrodynamics. In this study, a CFD model was developed which accounts for aeration, sludge rheology and geometry (i.e. bioreactor and membrane module). This MBR CFD model was then applied to two full-scale MBRs and was successfully validated against experimental results. The effect of sludge settling and rheology was found to have a minimal impact on the bulk mixing (i.e. the residence time distribution).

Internal dosimetry contamination: update of revision of the dose coefficients for intakes of radionuclides by workers

International Nuclear Information System (INIS)

Gomez Parada, I.; Rojo, A.M.; Sanguineti, R.

1995-01-01

ICRP publication 60 introduces new biological information related to the detriment associated with radiation exposures. The International Commission on Radiological Protection has also issued, in publications 57, 67 y 69, new biokinetic models for selected radionuclides since the issue of publication 30. In publication 66 the new human respiratory tract model for radiological protection is described. The aim of the present paper is to compare values of dose coefficients for workers calculated using the new tissue weighting factors, biokinetic models and lung model with those given in publication 30.The software package LUPED 1.1 was used to calculate dose coefficients for inhalation and ingestion. When possible, some changes in the biokinetic models were made trying to incorporate new parameters. The following radionuclides were analysed: 60 Co, 90 Sr, 99m Tc, 131 I, 137 Cs, 239 Pu y 241 Am. Most of the inhalation dose coefficients calculated with the new assumptions are within a factor of three of those calculated using the ICRP 30 lung and biokinetic models. Generally, the inhalation dose coefficients calculated with the new respiratory tract model and assuming a 5μm AMAD are lower than those calculated using the ICRP 30 model and parameters. The inhalation dose coefficients are generally within 10-90 % of the corresponding Publication 61 values, the difference tending to increase for relative insoluble compounds. (author). 10 refs., 4 tabs

Effect of bacteria density and accumulated inert solids on the effluent pollutant concentrations predicted by the constructed wetlands model BIO_PORE

OpenAIRE

Samsó Campà, Roger; Blazquez, Jordi; Agullo Chaler, Nuria; Grau Barceló, Joan; Torres Cámara, Ricardo; García Serrano, Joan

2015-01-01

Constructed wetlands are a widely adopted technology for the treatment of wastewater in small communities. The understanding of their internal functioning has increased at an unprecedented pace over recent years, in part thanks to the use of mathematical models. BIO_PORE model is one of the most recent models developed for constructed wetlands. This model was built in the COMSOL Multiphysics (TM) software and implements the biokinetic expressions of Constructed Wetlands Model 1 (CWM1) to desc...

Modeling the effect of continuous infusion DTPA therapy on the retention and dosimetry of inhaled actinides

International Nuclear Information System (INIS)

Guilmette, R.A.; Muggenburg, B.A.

1988-01-01

A biokinetic model of the treatment of dogs that inhaled 241 AmO 2 aerosols with continuously infused DTPA has been adapted from a model previously published by Mewhinney and Griffith. This model simulated both the tissue retention and excretion of 241 Am, and was used to estimate the cumulative radiation doses to tissues at risk from 241 Am alpha radiation. The results showed that at 64 days after exposure, the liver dose of the DTPA-treated animals was 3% that of the corresponding controls, the skeletal dose was 2%, the kidney dose was 4%, and the lung dose was 67% of controls. This paper describes a biokinetic and dosimetric model that was adapted from a previously published model. It was developed to provide a means of estimating radiation doses for cases where continuously infused DTPA therapy is used to reduce radiation dose. The model was formulated for the case of 241 Am0 2 inhalation, a physicochemical form of Am that is moderately soluble in vivo, and one to which people have been exposed. Because adequate human data, particularly tissue data, are not available from cases of accidental human exposure to 241 Am, two published data sets from experiments in which Beagle dogs inhaled 241 Am0 2 aerosols have been used to obtain parameter estimates for the model. The model simulations were then used to provide dose estimates with and without infused-DTPA therapy. (author)

A physiologically based biokinetic model for cesium in the human body

International Nuclear Information System (INIS)

Leggett, R.W.; Williams, L.R.; Melo, D.R.; Lipsztein, J.L.

2003-01-01

A physiologically descriptive model of the biological behavior of cesium in the human body has been constructed around a detailed blood flow model. The rate of transfer from plasma into a tissue is determined by the blood perfusion rate and the tissue-specific extraction fraction of Cs during passage from arterial to venous plasma. Information on tissue-specific extraction of Cs is supplemented with information on the Cs analogues, K and Rb, and known patterns of discrimination between these metals by tissues. The rate of return from a tissue to plasma is estimated from the relative contents of Cs in plasma and the tissue at equilibrium as estimated from environmental studies. Transfers of Cs other than exchange between plasma and tissues (e.g. secretions into the gastrointestinal tract) are based on a combination of physiological considerations and empirical data on Cs or related elements. Model predictions are consistent with the sizable database on the time-dependent distribution and retention of radiocesium in the human body

LUDEP 1. 0, a personal computer program to implement the new ICRP respiratory tract model

Energy Technology Data Exchange (ETDEWEB)

Jarvis, N.S.; Birchall, A. (National Radiological Protection Board, Chilton (United Kingdom))

1994-01-01

The International Commission on Radiological Protection has recently approved a new model of the human respiratory tract. This model has been designed to represent realistically the deposition and biokinetic behaviour of inhaled radionuclides, and to calculate doses to the respiratory tract. In order to examine the practical application and radiological implications of the new model, a Personal Computer program has been developed. LUDEP 1.0 is a user-friendly program for the IBM-compatible PC which enables the user to calculate doses to the respiratory tract and to other organs. (author).

Estimating {sup 131}I biokinetics and radiation doses to the red marrow and whole body in thyroid cancer patients: probe detection versus image quantification

Energy Technology Data Exchange (ETDEWEB)

Willegaignon, Jose; Pelissoni, Rogerio Alexandre; Lima, Beatriz Christine de Godoy Diniz; Coura-Filho, George Barberio; Queiroz, Marcelo Araujo, E-mail: j.willegaignon@gmail.com [Instituto do Cancer do Estado de Sao Paulo Octavio Frias de Oliveira (ICESP), Sao Paulo, SP (Brazil); Sapienza, Marcelo Tatit; Buchpiguel, Carlos Alberto [Universidade de Sao Paulo (FM/USP), Sao Paulo, SP (Brazil). Faculdade de Medicina. Departamento de Radiologia

2016-05-15

Objective: to compare the probe detection method with the image quantification method when estimating {sup 131}I biokinetics and radiation doses to the red marrow and whole body in the treatment of thyroid cancer patients. Materials and methods: fourteen patients with metastatic thyroid cancer, without metastatic bone involvement, were submitted to therapy planning in order to tailor the therapeutic amount of {sup 131}I to each individual. Whole-body scans and probe measurements were performed at 4, 24, 48, 72, and 96 h after {sup 131}I administration in order to estimate the effective half-life (T{sub eff}) and residence time of {sup 131}I in the body. Results: the mean values for T{sub eff} and residence time, respectively, were 19 ± 9 h and 28 ± 12 h for probe detection, compared with 20 ± 13 h and 29 ± 18 h for image quantification. The average dose to the red marrow and whole body, respectively, was 0.061 ± 0.041 mGy/MBq and 0.073 ± 0.040 mGy/MBq for probe detection, compared with 0.066 ± 0.055 mGy/MBq and 0.078 ± 0.056 mGy/MBq for image quantification. Statistical analysis proved that there were no significant differences between the two methods for estimating the T{sub eff} (p = 0.801), residence time (p = 0.801), dose to the red marrow (p = 0.708), and dose to the whole body (p = 0.811), even when we considered an optimized approach for calculating doses only at 4 h and 96 h after {sup 131}I administration (p > 0.914). Conclusion: there is full agreement as to the feasibility of using probe detection and image quantification when estimating {sup 131}I biokinetics and red-marrow/whole-body doses. However, because the probe detection method is ineffective in identifying tumor sites and critical organs during radionuclide therapy and therefore liable to skew adjustment of the amount of {sup 131}I to be administered to patients under such therapy, it should be used with caution. (author)

Biokinetics of radioiodine (125I) during pre and post-natal development and the interference with the induction of developmental effects in the mouse brain

International Nuclear Information System (INIS)

Konermann, G.

1992-01-01

On day 13 post-conception, pregnant mice were injected with equal activities of either 125 I-sodium iodide or 5-( 125 I)-iodo-2-deoxyuridine in order to study the biokinetic behaviour in relation to the induction of developmental long-term damage to the brain. Brain weight, cortex diameters and alignment of cortical neurons were more affected by 125 I-IUdR (37-231 kBq.g -1 ) than by 125 I-NaI, consistent with decay sites within the DNA or mainly extranuclear sites, respectively. Dose calculations according to the MIRD scheme gave underestimates of the radiotoxicity, especially for the DNA bound 125 I. This is consistent with pronounced RBE effects derived from in vitro studies. The transfer of these RBE effects to the developing brain is, however, limited by the complex interference between the manifestation and compensation of damage within the prolonged response chains. (author)

Models for high cell density bioreactors must consider biomass volume fraction: Cell recycle example.

Science.gov (United States)

Monbouquette, H G

1987-06-01

Intrinsic models, which take into account biomass volume fraction, must be formulated for adequate simulation of high-biomass-density fermentations with cell recycle. Through comparison of corresponding intrinsic and non-intrinsic models in dimensionless form, constraints for non-intrinsic model usage in terms of biokinetic and fermenter operating parameters can be identified a priori. Analysis of a simple product-inhibition model indicates that the non-intrinsic approach is suitable only when the attainable biomass volume fraction in the fermentation broth is less than about 0.10. Inappropriate application of a non-intrinsic model can lead to gross errors in calculated substrate and product concentrations, substrate conversion, and volumetric productivity.

Models for high cell density bioreactors must consider biomass volume fraction: cell recycle example

Energy Technology Data Exchange (ETDEWEB)

Monbouquette, H.G.

1987-06-01

Intrinsic models, which take into account biomass volume fraction, must be formulated for adequate simulation of high-biomass-density fermentations with cell recycle. Through comparison of corresponding intrinsic and non-intrinsic models in dimensionless form, constraints for non-intrinsic model usage in terms of biokinetic and fermenter operating parameters can be identified a priori. Analysis of a simple product-inhibition model indicates that the non-intrinsic approach is suitable only when the attainable biomass volume fraction in the fermentation broth is less than about 0.10. Inappropriate application of a non-intrinsic model can lead to gross errors in calculated substrate and product concentrations, substrate conversion, and volumetric productivity. (Refs. 14).

Determination and reliability of dose coefficients for radiopharmaceuticals; Ermittlung der Zuverlaessigkeit von Dosiskoeffizienten fuer Radiopharmaka

Energy Technology Data Exchange (ETDEWEB)

Spielmann, V.; Li, W.B.; Zankl, M.; Oeh, U.

2015-11-15

The dose coefficients used in nuclear medicine for dose calculations of radiopharmaceuticals are based on recommendations by ICRP (International Commission on radiological protection) and the MIRD (Medical Internal Radiation Dose Committee) using mathematical models for the temporal activity distributions in organs and tissues (biokinetic models) and mathematical models of the human body. These models using an idealized human body do not include uncertainty estimations. The research project is aimed to determine the uncertainties and thus the reliability of the dose coefficients for radiopharmaceuticals and to identify the biokinetic and dosimetric parameters that contribute most of the uncertainties.

Prediction of iodine-131 biokinetics and radiation doses from therapy on the basis of tracer studies: an important question for therapy planning in nuclear medicine.

Science.gov (United States)

Willegaignon, José; Pelissoni, Rogério A; Lima, Beatriz C G D; Sapienza, Marcelo T; Coura-Filho, George B; Buchpiguel, Carlos A

2016-05-01

This study aimed to present a comparison of iodine-131 (I) biokinetics and radiation doses to red-marrow (rm) and whole-body (wb), following the administration of tracer and therapeutic activities, as a means of confirming whether I clearance and radiation doses for therapy procedures can be predicted by tracer activities. Eleven differentiated thyroid cancer patients were followed after receiving tracer and therapeutic I activity. Whole-body I clearance was estimated using radiation detectors and OLINDA/EXM software was used to calculate radiation doses to rm and wb. Tracer I activity of 86 (±14) MBq and therapeutic activity of 8.04 (±1.18) GBq were administered to patients, thereby producing an average wb I effective half-time and residence time of, respectively, 13.51 (±4.05) and 23.13 (±5.98) h for tracer activities and 13.32 (±3.38) and 19.63 (±4.77) h for therapy. Radiation doses to rm and wb were, respectively, 0.0467 (±0.0208) and 0.0589 (±0.0207) mGy/MBq in tracer studies and 0.0396 (±0.0169) and 0.0500 (±0.0163) mGy/MBq in therapy. Although the differences were not considered statistically significant between averages, those between the values of effective half-times (P=0.906), residence times (P=0.145), and radiation doses to rm (P=0.393) and to wb (P=0.272), from tracer and therapy procedures, large differences of up to 80% in wb I clearance, and up to 50% in radiation doses were observed when patients were analyzed individually, thus impacting on the total amount of I activity calculated to be safe for application in individual therapy. I biokinetics and radiation doses to rm and wb in therapy procedures are well predicted by diagnostic activities when average values of a group of patients are compared. Nonetheless, when patients are analyzed individually, significant differences may be encountered, thus implying that nuclear medicine therapy-planning requires due consideration of changes in individual patient-body status from

Dose absorbed in adults and children thyroid due to the I123 using the dosimetry MIRD and Marinelli

International Nuclear Information System (INIS)

Vasquez, M.; Castillo, C.; Cabrera, C.; Sarachaga, R.; Castaneda, J.; Diaz, E.

2014-08-01

Using the dosimetry MIRD, and representation Cristy-Eckerman in the thyroid gland and organs of their bio-kinetics when I 123 (Iodine) is used, the study demonstrates that the absorbed dose by the gland of an adult, children, and newly born, is their auto-dose, independent of the compartments number of their bio-kinetics. The dosimetric contributions of the organs of their bio-kinetics are insignificant. Their results are not significantly different to those obtained by the formalism MARINELLI (auto-dose) when it uses a sphere like glandular representation. In consequence, the kinetic model corresponding to the glandular representation decreases to a compartment, where the gland can also be represented like a sphere. (Author)

Dose absorbed in adults and children thyroid due to the I{sup 123} using the dosimetry MIRD and Marinelli; Dosis absorbida en tiroides de adultos y ninos debido al I{sup 123} utilizando las dosimetrias MIRD y Marinelli

Energy Technology Data Exchange (ETDEWEB)

Vasquez, M.; Castillo, C.; Cabrera, C.; Sarachaga, R.; Castaneda, J. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Ciudad Universitaria, Trujillo (Peru); Diaz, E., E-mail: marvva@hotmail.com [Universidade Federal do Rio Grande do Sul, Av. Paulo Gamma 110, Bairro Farropilhas, Porto Alegre, RS 90040-060 (Brazil)

2014-08-15

Using the dosimetry MIRD, and representation Cristy-Eckerman in the thyroid gland and organs of their bio-kinetics when I{sup 123} (Iodine) is used, the study demonstrates that the absorbed dose by the gland of an adult, children, and newly born, is their auto-dose, independent of the compartments number of their bio-kinetics. The dosimetric contributions of the organs of their bio-kinetics are insignificant. Their results are not significantly different to those obtained by the formalism MARINELLI (auto-dose) when it uses a sphere like glandular representation. In consequence, the kinetic model corresponding to the glandular representation decreases to a compartment, where the gland can also be represented like a sphere. (Author)

Biokinetic of plutonium in human beings. Analysis and modification of ICRP 67 model

International Nuclear Information System (INIS)

Luciani, A.; Castellani, C. M.

2001-01-01

A preliminary research of the available data and empirical functions for the plutonium excretion after injection was carried out. The ICRP model presented in the Publication no. 67 was then analyzed comparing its predictions for the activity in urine and, at a lesser extent, in feces and blood, with the collected data and empirical curves. The model was modified and an optimized age-related compartmental model was developed. A new skeletal model recently developed was also introduced and age depending bone remodelling rates were assumed on the basis of the ICRP Publication 70. This model provides a better agreement with measured urinary excretion data than the current ICRP 67 model, avoiding unphysiological assumptions such as the transfer of activity from soft tissue to urinary bladder, that were part of the ICRP model. The new optimized model predictions of the activity in faeces and in blood after an injection are also closer to the available data than the ICRP 67 estimations. A good agreement with the partitioning factor of plutonium between skeleton and liver obtained from different autopsy studies was also observed [it

Role of bio-effect models in improving radiotherapy of cancer

International Nuclear Information System (INIS)

Rao, B.S.

2013-01-01

Application of linear quadratic model of cell survival in radiotherapy has enabled to successfully predict the response of both the normal tissues and tumours. Even the simplest form of BED (biological effective dose) equation for fractionated radiotherapy could precisely predict the late normal tissue complications resulting from large dose per fraction. These observations have led to the development MFD (multiple fractions daily) protocol, with the specific objective of reducing late normal tissue morbidity. Protraction of treatment and consequent loss of BED and tumour control; multiple fractions delivered without adequate intervals resulting in incomplete repair of sub-lethal damage and consequent normal tissue complications, have been explained successfully by the LQ model. In the recent past LDR (low dose rate) brachytherapy is mostly replaced by HDR (high dose rate) technique. A series of calculations based on tumour bio-kinetics parameters, as well as the geometric sparing provides a sound rationale for replacing LDR technique by HDR technique. Some of the calculations relevant to this will be presented during this talk. Bio-effect models can also provide insight in to the rationale of RIT (radio-immunotherapy). With an adequate knowledge of biological half-life of antibodies in the tumour/critical organs, and biological uptake half-time in the tumour, it is possible to evaluate the efficacy of a number of radio-nuclides in RIT. Calculations based on LQ models suggest that longer lived isotopes such as 32 P, 86 Rb, 144m In may have an advantage over the shorter lived radio-nuclides. A clear knowledge of the various parameters like/values, potentially doubling time of tumour and other bio-kinetic parameters may hold the key for successful application of bio-effect models in predicting the response to radiotherapy. Feedback from the clinics will further help in refining and validating the existing models. (author)

New framework for standardized notation in wastewater treatment modelling

DEFF Research Database (Denmark)

Corominas, L.; Rieger, L.; Takacs, I.

2010-01-01

Many unit process models are available in the field of wastewater treatment. All of these models use their own notation, causing problems for documentation, implementation and connection of different models (using different sets of state variables). The main goal of this paper is to propose a new...... is a framework that can be used in whole plant modelling, which consists of different fields such as activated sludge, anaerobic digestion, sidestream treatment, membrane bioreactors, metabolic approaches, fate of micropollutants and biofilm processes. The main objective of this consensus building paper...... notational framework which allows unique and systematic naming of state variables and parameters of biokinetic models in the wastewater treatment field. The symbols are based on one main letter that gives a general description of the state variable or parameter and several subscript levels that provide...

Biokinetics of radioiodine ( sup 125 I) during pre and post-natal development and the interference with the induction of developmental effects in the mouse brain

Energy Technology Data Exchange (ETDEWEB)

Konermann, G. (Freiburg Univ. (Germany). Inst. fuer Biophysik und Strahlenbiologie)

1992-01-01

On day 13 post-conception, pregnant mice were injected with equal activities of either {sup 125}I-sodium iodide or 5-({sup 125}I)-iodo-2-deoxyuridine in order to study the biokinetic behaviour in relation to the induction of developmental long-term damage to the brain. Brain weight, cortex diameters and alignment of cortical neurons were more affected by {sup 125}I-IUdR (37-231 kBq.g{sup -1}) than by {sup 125}I-NaI, consistent with decay sites within the DNA or mainly extranuclear sites, respectively. Dose calculations according to the MIRD scheme gave underestimates of the radiotoxicity, especially for the DNA bound {sup 125}I. This is consistent with pronounced RBE effects derived from in vitro studies. The transfer of these RBE effects to the developing brain is, however, limited by the complex interference between the manifestation and compensation of damage within the prolonged response chains. (author).

Biokinetics of a transuranic ({sup 238}PU) and a rare earth element ({sup 152}Eu) in the lobster (Homarus gammarus): transfer mechanisms (accumulation and detoxification) in organs and at the cellular level; Biocinetiques d'un element transuranien, le {sup 238}PU, et d'une terre rare, le {sup 152}EU, chez le homard homarus gammarus (organes et niveau cellulaire) modalites des transferts (accumulation et detoxication)

Energy Technology Data Exchange (ETDEWEB)

Tocquet, N

1995-07-01

The work presented here is an experimental investigation of the biokinetics of transfer of a transuranic and a rare earth element ({sup 238}Pu and {sup 152}Eu) in the lobster Homarus gammarus. The study of {sup 238}Pu biokinetics forms part of a wider framework of research concerning the transfer of transuranic elements in marine species, while the study of {sup 152}Eu is carried out with a view to supporting the analogy between the behaviour of transuranics and rare earths in living organisms. Exactly the same experimental protocol, based on techniques from various disciplines (biology, biochemistry and metrology), was used to Investigate the biokinetics of transfer of these two radionuclides. The Individual lobsters were radiolabelled by means of one-shot or chronic ingestion of spiked meals. As the first approach, the kinetics and transfer mechanisms were studied In whole animal samples and in different organs distinct series of pathways through the different organs were identified in the case of both radionuclides, being mainly linked to digestive processes induced by the meal as well as the transport function of hemo-lymph in this way, the Important role of the digestive gland was picked out, with two of four cellular types displaying a successive involvement In the fixation and then the retention of the studied radionuclides. As a corroborative approach, the digestive gland was subjected to a more detailed investigation with the aim of describing the mechanisms of Incorporation and elucidating transfer processes at the cellular and molecular levels. {sup 238}Pu is preferentially partitioned into the cytosol, where it is associated with various constituents such as ferritin (iron-storing protein). {sup 152}Eu is more diffusely distributed in the hepato-pancreatic cells, while the lysosomes appear to play a more important role during transfer. The results obtained in this study, both on the macroscopic scale (i.e. the whole animal and different organs) as well

Biokinetics of a transuranic ({sup 238}PU) and a rare earth element ({sup 152}Eu) in the lobster (Homarus gammarus): transfer mechanisms (accumulation and detoxification) in organs and at the cellular level; Biocinetiques d'un element transuranien, le {sup 238}PU, et d'une terre rare, le {sup 152}EU, chez le homard homarus gammarus (organes et niveau cellulaire) modalites des transferts (accumulation et detoxication)

Energy Technology Data Exchange (ETDEWEB)

Tocquet, N

1995-07-01

The work presented here is an experimental investigation of the biokinetics of transfer of a transuranic and a rare earth element ({sup 238}Pu and {sup 152}Eu) in the lobster Homarus gammarus. The study of {sup 238}Pu biokinetics forms part of a wider framework of research concerning the transfer of transuranic elements in marine species, while the study of {sup 152}Eu is carried out with a view to supporting the analogy between the behaviour of transuranics and rare earths in living organisms. Exactly the same experimental protocol, based on techniques from various disciplines (biology, biochemistry and metrology), was used to Investigate the biokinetics of transfer of these two radionuclides. The Individual lobsters were radiolabelled by means of one-shot or chronic ingestion of spiked meals. As the first approach, the kinetics and transfer mechanisms were studied In whole animal samples and in different organs distinct series of pathways through the different organs were identified in the case of both radionuclides, being mainly linked to digestive processes induced by the meal as well as the transport function of hemo-lymph in this way, the Important role of the digestive gland was picked out, with two of four cellular types displaying a successive involvement In the fixation and then the retention of the studied radionuclides. As a corroborative approach, the digestive gland was subjected to a more detailed investigation with the aim of describing the mechanisms of Incorporation and elucidating transfer processes at the cellular and molecular levels. {sup 238}Pu is preferentially partitioned into the cytosol, where it is associated with various constituents such as ferritin (iron-storing protein). {sup 152}Eu is more diffusely distributed in the hepato-pancreatic cells, while the lysosomes appear to play a more important role during transfer. The results obtained in this study, both on the macroscopic scale (i.e. the whole animal and different organs) as well

From Technique of Tattooing to Biokinetics and Toxicology of Injected Tattoo Ink Particles and Chemicals.

Science.gov (United States)

Serup, Jørgen

2017-01-01

Tattoo colourants are colourful nano- and microparticles, which are practically insoluble and thus permanent once installed in the dermis by the tattooist. Tattoo ink also has soluble ingredients and contaminants. Pigments can distribute via the lymph and possibly also directly to the blood, and a minute fraction may over time undergo metabolic breakdown and as hapten(s) induce allergic reactions of red tattoos. Carbon black of black tattoos has a tendency to agglomerate and form larger bodies that can elicit foreign body reactions in black tattoos and even granuloma formation with overlap to sarcoidosis in the clinic. Very little is known about the biokinetics and safety profile of the many tattoo pigments in use, and no specific pigment-related chemical of tattoo ink causing identified adverse reactions in humans has been depicted. Inks have many ingredients and contaminants. Insoluble and soluble ingredients of inks supposedly have very different characteristics of absorption, distribution, metabolism, and excretion, with pigments being extremely slowly excreted, contrasting soluble ingredients with fast elimination. Tattoos are a single-dose exposure. Controlling the safety of tattoo inks by banning potentially critical chemicals hitherto has been unsuccessful due to lacking documentation of clinical and epidemiological relevance and because the tattoo industry is already internationally established, free, and in the ownership of the people. Doctors treating patients with tattoo complications consequently have a key role in identifying risk situations and local outbreaks, which needs clarification, therapy, and the intervention of authorities. In the treatment of complications, as seen in general practice and in other specialties, basic insight into the fate of tattoo pigments in the body is necessary. Tattoo complications are complicated and facetted with many entities and disease mechanisms; they are a new subspecialty in medicine and dermatology. © 2017 S

Studies on the excretion ratio of U for a group of occupationally exposed subjects

International Nuclear Information System (INIS)

Pullat, V.R.; Dang, H.S.

1999-01-01

The ICRP biokinetic model of uranium was validated by using the site specific and population specific Indian data on uranium. The daily urinary excretion of uranium and its concentration in blood serum were simultaneously measured in forty occupational workers of uranium oxide processing plant (Y class). In view of the extremely low concentration of uranium in blood serum (<1.0 ppb), a highly sensitive analytical method using radiochemical neutron activation analysis technique (RNAA) was developed, standardised and applied to determine the concentration of uranium in blood serum and urine samples. The results of the estimation showed a statistically significant linear correlation (p<0.01) between the serum burden and the corresponding daily urinary excretion. The median excretion ratio obtained for the forty occupational workers was estimated to be 92% in comparison to 98% expected on the basis of ICRP biokinetic model of uranium. The study indicates that the ICRP biokinetic model can be effectively employed for the internal dose assessment of occupational workers by using bioassay monitoring. (author)

Biokinetics and dosimetry of a hybrid formulation of {sup 9{sup m}}Tc-BN and {sup 99m}Tc-RGD{sub 2} starting from optic images in a murine model; Biocinetica y dosimetria de una formulacion hibrida de {sup 99m}Tc-BN y {sup 99m}Tc-RGD{sub 2} a partir de imagenes opticas en un modelo murino

Energy Technology Data Exchange (ETDEWEB)

Cornejo A, L. G.

2015-07-01

This work has the purpose of evaluate the biokinetics and absorbed dose of radiation of hybrid formulation {sup 99m}Tc-BN /{sup 99m}Tc-RGD{sub 2} in a murine model by optical imaging techniques using the multimodal preclinical in vivo image system Xtreme. The used method were the {sup 99m}Tc-BN, {sup 99m}Tc-RGD{sub 2} and {sup 99m}Tc-BN/{sup 99m}Tc-RGD{sub 2} formulas, with specific recognition for GRPr and the integrin s α(v)β(3) and α(v)β(5) respectively, was injected in the vein tail of three nude mousses with induce breast cancer tumors (cell line T-47-D), by the preclinical multimodal imaging system Xtreme (Bruker), optical images in different times was acquired (5, 10, 20 min, 2 and 24 h), using Images Processing Toolbox of MATLAB these images was transform from RGB format to gray scales and sectioned in five independent images corresponding to heart, kidneys, bladder and tumor areas. The intensity of each images was computed in counts per pixel, then those intensities was corrected for background, attenuation and scattering, using different factors for each phenomena previously calculated. Finally the activity values quantified vs time was fitted into a biokinetic model to obtain the disintegrations number and cumulate activities in each organ. With these data the radiation absorbed dose were calculated using MIRD methodology. Results: The number of disintegration and absorbed dose calculated in MBq h/MBq and mGy/MBq, of injected mouse with the {sup 99m}Tc-BN/{sup 99m}Tc-RGD{sub 2} formulation, was: 0.035 ± 0.65 E-02, 0.25 x 10{sub -5} ± 0.46 E-07; 0.393 ± 0.51 E-1, 2.85 E-05 ± 3.7 E-06; 0.306 ± 0.21 E-01, 2.11 E-05 ± 1.45 E-06 and 0.151 ± 0.19 E-01, 1.09 E-05 ± 1.42 E-06 , in heart, kidneys, bladder and tumor, respectively. The number of disintegration obtained in kidneys is comparable to those reported for Trinidad B. 2014 Conclusions: Our results demonstrated that using optical images and a code for image analyses development in MATLAB, could

Modelling the effect of continuous infusion DTPA therapy on the retention and dosimetry of inhaled actinides

International Nuclear Information System (INIS)

Guilmette, R.A.; Muggenburg, B.A.

1989-01-01

A biokinetic model of the treatment of dogs that inhaled 241 AmO 2 aerosols with continuously infused DTPA has been adapted from a previously published model by Mewhinney and Griffith. This model was parameterised to simulate both the tissue retention and the excretion of 241 Am, and was used to estimate the cumulative radiation doses to tissues at risk from the α radiation of 241 Am. The results showed that at 64 days after exposure, the liver dose of the DTPA-treated animals was 3% that of the corresponding controls, the skeleton dose was 2%, the kidney dose was 4% and the lung dose was 67% of controls. (author)

Towards a consensus-based biokinetic model for green microalgae - The ASM-A.

Science.gov (United States)

Wágner, Dorottya S; Valverde-Pérez, Borja; Sæbø, Mariann; Bregua de la Sotilla, Marta; Van Wagenen, Jonathan; Smets, Barth F; Plósz, Benedek Gy

2016-10-15

Cultivation of microalgae in open ponds and closed photobioreactors (PBRs) using wastewater resources offers an opportunity for biochemical nutrient recovery. Effective reactor system design and process control of PBRs requires process models. Several models with different complexities have been developed to predict microalgal growth. However, none of these models can effectively describe all the relevant processes when microalgal growth is coupled with nutrient removal and recovery from wastewaters. Here, we present a mathematical model developed to simulate green microalgal growth (ASM-A) using the systematic approach of the activated sludge modelling (ASM) framework. The process model - identified based on a literature review and using new experimental data - accounts for factors influencing photoautotrophic and heterotrophic microalgal growth, nutrient uptake and storage (i.e. Droop model) and decay of microalgae. Model parameters were estimated using laboratory-scale batch and sequenced batch experiments using the novel Latin Hypercube Sampling based Simplex (LHSS) method. The model was evaluated using independent data obtained in a 24-L PBR operated in sequenced batch mode. Identifiability of the model was assessed. The model can effectively describe microalgal biomass growth, ammonia and phosphate concentrations as well as the phosphorus storage using a set of average parameter values estimated with the experimental data. A statistical analysis of simulation and measured data suggests that culture history and substrate availability can introduce significant variability on parameter values for predicting the reaction rates for bulk nitrate and the intracellularly stored nitrogen state-variables, thereby requiring scenario specific model calibration. ASM-A was identified using standard cultivation medium and it can provide a platform for extensions accounting for factors influencing algal growth and nutrient storage using wastewater resources. Copyright �

Stable isotopes as tracers for radionuclides

International Nuclear Information System (INIS)

Giussani, A.; Bartolo, D. de; Cantone, M.C.; Zilker, T.; Greim, H.; Roth, P.; Werner, E.

2000-01-01

The assessment of internal dose after incorporation of radionuclides requires as input data the knowledge of the uptake into the systemic circulation, the distribution and retention in selected organs, the excretion pathways. Realistic biokinetic models are needed for reliable estimates, correct interpretation of bioassay measurements, appropriate decision-making in radiological emergencies. For many radionuclides, however, the biokinetic models currently recommended are often generic, with very few specific parameters, due to the lack of experimental human data. The use of stable isotopes as tracers enables to determine important biokinetic parameters such as the fractional uptake, the clearance from the transfer compartment, the excretion patterns under experimentally controlled conditions. The subjects investigated are not exposed to any radiation risk, so this technique enables to obtain biokinetic information also for sensitive groups of the population, such as children or pregnant women, and to determine age- and gender-specific model parameters. Sophisticated analytical method, able to discriminate and quantitate different isotopes of the same element in complex matrices such as biological fluids, have to be purposely developed and optimized. Activation analysis and mass spectrometry are the most proper techniques of choice. Experiments were conducted with molybdenum, tellurium, ruthenium and zirconium. Activation analysis with protons, thermal ionization mass spectrometry and inductively coupled mass spectrometry were employed for the determination of stable isotopes of these elements in blood plasma and urine samples. Several deviations from the predictions of the ICRP models were observed. For example, modifications to the current model for molybdenum have been suggested on the basis of these results. The dose coefficients to the target regions calculated with this proposed model are even of one order of magnitude different than the ICRP estimates

Implications of human tissue studies for radiation protection

International Nuclear Information System (INIS)

Kathren, R.L.

1988-01-01

Through radiochemical analysis of voluntary tissue donations, the U.S. Transuranium and Uranium Registries (USTR) are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole-body contributions to the USTR revealed an inverse proportionality between actinide concentration and bone ash. The analysis of a whole body with significant 241 Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies with tissues obtained at autopsy suggest that existing biokinetic models for 238 Pu and 241 Am and the currently accepted models and limits on intake, which use these models as their basis, may be inaccurately implying that revisions of existing safety standards may be necessary. Other studies of the registries are designed to evaluate in-vivo estimates of actinide deposition with those derived from postmortem tissue analysis, to compare results of animal experiments with human data, and to review histopathologic slides for tissue changes that might be attributable to exposure to transuranic elements. The implications of these recent findings and other work of the registries is discussed from the standpoint of this potential effect on biokinetic modeling, internal dose assessment, and safety standards and operational health physics practices

Implications of human tissue studies for radiation protection.

Science.gov (United States)

Kathren, R L

1988-08-01

Through radiochemical analysis of voluntary tissue donations, the U.S. Transuranium and Uranium Registries (USTR) are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole-body contributions to the USTR revealed an inverse proportionality between actinide concentration and bone ash. The analysis of a whole body with significant 241Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies with tissues obtained at autopsy suggest that existing biokinetic models for 238Pu and 241Am and the currently accepted models and limits on intake, which use these models as their basis, may be inaccurately implying that revisions of existing safety standards may be necessary. Other studies of the registries are designed to evaluate in-vivo estimates of actinide deposition with those derived from postmortem tissue analysis, to compare results of animal experiments with human data, and to review histopathologic slides for tissue changes that might be attributable to exposure to transuranic elements. The implications of these recent findings and other work of the registries is discussed from the standpoint of this potential effect on biokinetic modeling, internal dose assessment, and safety standards and operational health physics practices.

Kit preparation and biokinetics in women of 99mTc-EDDA/HYNIC-E-[c(RGDfK)]2 for breast cancer imaging.

Science.gov (United States)

Ortiz-Arzate, Zareth; Santos-Cuevas, Clara L; Ocampo-García, Blanca E; Ferro-Flores, Guillermina; García-Becerra, Rocío; Estrada, Gisela; Gómez-Argumosa, Edgar; Izquierdo-Sánchez, Vanessa

2014-04-01

In breast cancer, α(ν)β(3) and/or α(ν)β(5) integrins are overexpressed in both endothelial and tumour cells. Radiolabelled peptides based on the Arg-Gly-Asp (RGD) sequence are radiopharmaceuticals with high affinity and selectivity for these integrins. The RGD-dimer peptide (E-[c(RGDfK)]2) radiolabelled with (99m)Tc has been reported as a radiopharmaceutical with a 10-fold higher affinity for the α(ν)β(3) integrin compared with the RGD-monomer. Ethylenediamine-N,N'-diacetic acid (EDDA) is a hydrophilic molecule that may favour renal excretion when used as coligand in the (99m)Tc labelling of hydrazinonicotinamide (HYNIC) peptides and can easily be formulated in a lyophilized kit. The aim of this study was to establish a biokinetic model for (99m)Tc-EDDA/HYNIC-E-[c(RGDfK)]2 prepared from lyophilized kits and evaluate its dosimetry as a tumour-imaging agent in seven healthy women and three breast cancer patients. (99m)Tc labelling was performed by adding sodium pertechnetate solution and 0.2 mol/l phosphate buffer (pH 7.0) to a lyophilized formulation containing E-[c(RGDfK)]2, EDDA, tricine, mannitol and stannous chloride. The radiochemical purity was evaluated using reverse-phase high-performance liquid chromatography and instant thin-layer chromatography on silica gel analyses. Stability studies in human serum were carried out using size-exclusion high-performance liquid chromatography. In-vitro cell uptake was tested using breast cancer cells (MCF7, T47D and MDA-MB-231) with blocked and nonblocked receptors. Biodistribution and tumour uptake were determined in MCF7 tumour-bearing nude mice with blocked and nonblocked receptors, and images were obtained using a micro-SPECT/PET/CT. Whole-body images from seven healthy women were acquired at 0.5, 1, 3, 6 and 24 h after (99m)Tc-EDDA/HYNIC-E-[c(RGDfK)]2 administration with radiochemical purities greater than 94%. Regions of interest were drawn around the source organs at each time frame. Each region of

Assessing internal exposure in the absence of an appropriate model: two cases involving an incidental inhalation of transuranic elements

International Nuclear Information System (INIS)

Blanchin, N.; Grappin, L.; Guillermin, A.M.; Lafon, P.; Miele, A.; Berard, P.; Blanchardon, E.; Fottorino, R.

2008-01-01

Two incidents involving internal exposure by inhalation of transuranic compounds are presented herein. The results of the measurements of urinary and faecal excretions of the two individuals involved do not concur with the values predicted by the ICRP models that should be applied by default, according to the circumstances of the incidents and the chemical form of the products involved: oxide in the first case and nitrate in the second. These cases are remarkable in the similarity of their biokinetic behaviour even though they occurred in different situations and involved different chemical compounds. Both situations provide an illustration of the management of internal contamination events. The precautions to be taken and the questions that the physician should ask himself in the estimation of the internal dose are listed as follows: What type of examinations should be prescribed and at what frequency? What analysis results should be used in assessing the dose? How can the effect of the Ca-DTPA treatment be assessed? How long is it necessary to perform radio toxicological exams before assessing the dose? What should be done if the ICRP model corresponding to the initial circumstances does not fit the measurement data? Finally, our selected hypotheses, used to explain specific biokinetic behaviour and to estimate its intake in both cases, are detailed. These incidental contaminations suggest that further studies should be carried out to develop a new model for inhalation of transuranic compounds that would follow neither the S nor the M absorption type of the respiratory tract model of ICRP publication 66. (authors)

Assessing internal exposure in the absence of an appropriate model: two cases involving an incidental inhalation of transuranic elements

International Nuclear Information System (INIS)

Blanchin, Nicolas; Fottorino, Robert; Grappin, Louise; Guillermin, Anne-Marie; Lafon, Philippe; Miele, Alain; Berard, Philippe; Blanchardon, Eric

2008-01-01

Two incidents involving internal exposure by inhalation of transuranic compounds are presented herein. The results of the measurements of urinary and faecal excretions of the two individuals involved do not concur with the values predicted by the ICRP models that should be applied by default, according to the circumstances of the incidents and the chemical form of the products involved: oxide in the first case and nitrate in the second. These cases are remarkable in the similarity of their biokinetic behaviour even though they occurred in different situations and involved different chemical compounds. Both situations provide an illustration of the management of internal contamination events. The precautions to be taken and the questions that the physician should ask himself in the estimation of the internal dose are listed as follows: a) What type of examinations should be prescribed and at what frequency?; b) What analysis results should be used in assessing the dose?; c) How can the effect of the Ca-DTPA treatment be assessed?; d) How long is it necessary to perform radio toxicological exams before assessing the dose?; e) What should be done if the ICRP model corresponding to the initial circumstances does not fit the measurement data? Finally, our selected hypotheses, used to explain specific biokinetic behaviour and to estimate its intake in both cases, are detailed. These incidental contaminations suggest that further studies should be carried out to develop a new model for inhalation of transuranic compounds that would follow neither the S nor the M absorption type of the respiratory tract model of ICRP publication 66. (author)

Evaluation of the absorbed dose to the lungs due to Xe133 and Tc99m (MAA)

International Nuclear Information System (INIS)

Vazquez A, M.; Murillo C, F.; Castillo D, C.; Sifuentes D, Y.; Sanchez S, P.; Rojas P, E.; Marquez P, F.

2015-10-01

The absorbed dose in lungs of an adult patient has been evaluated using the biokinetics of radiopharmaceuticals containing Xe 133 or Tc 99m (MAA). The absorbed dose was calculated using the MIRD formalism, and the Cristy-and Eckerman lungs model. The absorbed dose in the lungs due to 133 Xe is 0.00104 mGy/MBq. Here, the absorbed dose due to remaining tissue, included in the 133 Xe biokinetics is not significant. The absorbed dose in the lungs, due Tc 99m (MAA), is 0.065 mGy/MBq. Approximately, 4.6% of the absorbed dose is due to organs like liver, kidneys, bladder, and the rest of tissues, included in the Tc 99m biokinetics. Here, the absorbed dose is very significant to be overlooked. The dose contribution is mainly due to photons emitted by the liver. (Author)

Age-dependent dosimetry and metabolism

International Nuclear Information System (INIS)

Taylor, D.M.

1992-01-01

The release of radionuclides into the environment following the Chernobyl disaster in 1986 created an urgent need for internationally acceptable dose coefficients for calculating the doses delivered to all members of the public, from conception to old age. Organ masses and the kinetics of distribution and retention of elements in humans generally vary with age and often not in simple linear relationship to body weight. Unless variations are considered calculated radiation doses to children may be seriously underestimated. The International Commission on Radiological Protection created in 1987 a Task Group on Age-dependent Doses to Members of the Public from Intake of Radionuclides (AGDOS). The work of AGDOS and the general problems encountered in deriving age-dependent dose coefficients will be discussed in this paper. The first two AGDOS reports, ICRP Publication 56 Parts 1 and 2, provide dose coefficients for the ages 3 months, 1, 5, 10, 15 years and for adults for the 21 elements considered to be of most immediate importance for radiation protection. To develop these dose coefficients, the ICRP Publication 30 dosimetric and biokinetic models were reevaluated and extended. The basic dosimetric model is retained but equivalent dose is now integrated from age at intake to 70 years and the new ICRP Publication 60 tissue weighting factors are incorporated. The development of age-dependent biokinetic models is complicated by the lack of age-related human, or even animal data for the majority of the elements. Thus in formulating the models it has been necessary to use all the available information, biokinetic, physiological chemical and biochemical, and to adopt a number of new approaches including the development of generic biokinetic models for chemically related families of elements such as the actinides and the alkaline earth elements. (author)

Shall we upgrade one-dimensional secondary settler models used in WWTP simulators? - An assessment of model structure uncertainty and its propagation.

Science.gov (United States)

Plósz, Benedek Gy; De Clercq, Jeriffa; Nopens, Ingmar; Benedetti, Lorenzo; Vanrolleghem, Peter A

2011-01-01

In WWTP models, the accurate assessment of solids inventory in bioreactors equipped with solid-liquid separators, mostly described using one-dimensional (1-D) secondary settling tank (SST) models, is the most fundamental requirement of any calibration procedure. Scientific knowledge on characterising particulate organics in wastewater and on bacteria growth is well-established, whereas 1-D SST models and their impact on biomass concentration predictions are still poorly understood. A rigorous assessment of two 1-DSST models is thus presented: one based on hyperbolic (the widely used Takács-model) and one based on parabolic (the more recently presented Plósz-model) partial differential equations. The former model, using numerical approximation to yield realistic behaviour, is currently the most widely used by wastewater treatment process modellers. The latter is a convection-dispersion model that is solved in a numerically sound way. First, the explicit dispersion in the convection-dispersion model and the numerical dispersion for both SST models are calculated. Second, simulation results of effluent suspended solids concentration (XTSS,Eff), sludge recirculation stream (XTSS,RAS) and sludge blanket height (SBH) are used to demonstrate the distinct behaviour of the models. A thorough scenario analysis is carried out using SST feed flow rate, solids concentration, and overflow rate as degrees of freedom, spanning a broad loading spectrum. A comparison between the measurements and the simulation results demonstrates a considerably improved 1-D model realism using the convection-dispersion model in terms of SBH, XTSS,RAS and XTSS,Eff. Third, to assess the propagation of uncertainty derived from settler model structure to the biokinetic model, the impact of the SST model as sub-model in a plant-wide model on the general model performance is evaluated. A long-term simulation of a bulking event is conducted that spans temperature evolution throughout a summer

Evaluation of the absorbed dose to the lungs due to Xe{sup 133} and Tc{sup 99m} (MAA); Evaluacion de la dosis absorbida en los pulmones debido al Xe{sup 133} y Tc{sup 99m} (MAA)

Energy Technology Data Exchange (ETDEWEB)

Vazquez A, M.; Murillo C, F.; Castillo D, C.; Sifuentes D, Y.; Sanchez S, P. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Trujillo (Peru); Rojas P, E. [Instituto Peruano de Energia Nuclear, Av. Canada 1470, Lima (Peru); Marquez P, F., E-mail: marvva@hotmail.com [Instituto Nacional de Enfermedades Neoplasicas, Av. Angamos 2520, Lima (Peru)

2015-10-15

The absorbed dose in lungs of an adult patient has been evaluated using the biokinetics of radiopharmaceuticals containing Xe{sup 133} or Tc{sup 99m} (MAA). The absorbed dose was calculated using the MIRD formalism, and the Cristy-and Eckerman lungs model. The absorbed dose in the lungs due to {sup 133}Xe is 0.00104 mGy/MBq. Here, the absorbed dose due to remaining tissue, included in the {sup 133}Xe biokinetics is not significant. The absorbed dose in the lungs, due Tc{sup 99m} (MAA), is 0.065 mGy/MBq. Approximately, 4.6% of the absorbed dose is due to organs like liver, kidneys, bladder, and the rest of tissues, included in the Tc{sup 99m} biokinetics. Here, the absorbed dose is very significant to be overlooked. The dose contribution is mainly due to photons emitted by the liver. (Author)

Particle size distributions, size concentration relationships, and adherence to hands of selected geologic media derived from mining, smelting, and quarrying activities

Energy Technology Data Exchange (ETDEWEB)

Bergstrom, Carolyn; Shirai, Jeffry; Kissel, John, E-mail: jkissel@uw.edu

2011-09-15

Hand-to-mouth activity, especially in children, is a potentially significant pathway of exposure to soil contaminants. Hand-mouthing behavior is of particular concern in areas impacted by mining, smelting, and quarrying activities as these activities may lead to elevated levels of heavy metals in soil. In order to estimate potential exposures to contaminated geologic media attributable to hand-to-mouth contact, it is useful to characterize adherence of those media to skin, as contaminant concentrations in adhered media may differ greatly from unfractionated, whole media concentrations. Such an investigation has been undertaken to aid estimation of exposures to arsenic, cadmium, lead, and zinc in nine different geologic media collected in the Pacific Northwest region of the United States. After establishing the particle size distribution of each medium (fractions < 63 {mu}m, 63-150 {mu}m, 150-250 {mu}m, and 250 {mu}m-2 mm were determined) and target elemental concentrations within each particle size fraction, an active handling protocol involving six volunteers was conducted. Wet media always adhered to a greater extent than dry media and adhered media generally had higher elemental concentrations than bulk media. Regression analyses suggest smaller particle fractions may have higher elemental concentrations. Results of application of a maximum likelihood estimation technique generally indicate that handling of dry media leads to preferential adherence of smaller particle sizes, while handling of wet media does not. Because adhered material can differ greatly in particle size distribution from that found in bulk material, use of bulk concentrations in exposure calculations may lead to poor estimation of actual exposures. Since lead has historically been a metal of particular concern, EPA's Integrated Exposure Uptake Biokinetic (IEUBK) Model was used to examine the potential consequences of evaluating ingestion of the selected media assuming concentrations in

Experimental and theoretical study of the transport of silver nanoparticles at their prolonged administration into a mammal organism

Science.gov (United States)

Antsiferova, A. A.; Buzulukov, Yu. P.; Kashkarov, P. K.; Kovalchuk, M. V.

2016-11-01

The transport of silver nanoparticles in the organism of laboratory animals has been investigated. A mathematical model of the biokinetics of prolonged administration of nonmetabolizable and nonaglomerating pharmaceutical preparations is proposed, and its analytical solution is found. Based on the experimental data on the prolonged introduction and excretion of colloidal silver nanoparticles and the numerical approximation of the solutions to the equations for the proposed model, time dependences of the silver mass content in brain and blood are obtained and some other important biokinetic parameters are determined. It is concluded that both chronic1 and subchronic2 peroral application of these nanoparticles as an biologically active additive or antiseptic is potentially dangerous.

Dynamic model for the assessment of radiological exposure to marine biota

Energy Technology Data Exchange (ETDEWEB)

Vives i Batlle, J. [Westlakes Scientific Consulting Ltd, The Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom)], E-mail: jordi.vives@westlakes.ac.uk; Wilson, R.C.; Watts, S.J.; Jones, S.R.; McDonald, P.; Vives-Lynch, S. [Westlakes Scientific Consulting Ltd, The Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria CA24 3LN (United Kingdom)

2008-11-15

A generic approach has been developed to simulate dynamically the uptake and turnover of radionuclides by marine biota. The approach incorporates a three-compartment biokinetic model based on first order linear kinetics, with interchange rates between the organism and its surrounding environment. Model rate constants are deduced as a function of known parameters: biological half-lives of elimination, concentration factors and a sample point of the retention curve, allowing for the representation of multi-component release. The new methodology has been tested and validated in respect of non-dynamic assessment models developed for regulatory purposes. The approach has also been successfully tested against research dynamic models developed to represent the uptake of technetium and radioiodine by lobsters and winkles. Assessments conducted on two realistic test scenarios demonstrated the importance of simulating time-dependency for ecosystems in which environmental levels of radionuclides are not in equilibrium.

Significance of uncertainties derived from settling tank model structure and parameters on predicting WWTP performance - A global sensitivity analysis study

DEFF Research Database (Denmark)

Ramin, Elham; Sin, Gürkan; Mikkelsen, Peter Steen

2011-01-01

Uncertainty derived from one of the process models – such as one-dimensional secondary settling tank (SST) models – can impact the output of the other process models, e.g., biokinetic (ASM1), as well as the integrated wastewater treatment plant (WWTP) models. The model structure and parameter...... and from the last aerobic bioreactor upstream to the SST (Garrett/hydraulic method). For model structure uncertainty, two one-dimensional secondary settling tank (1-D SST) models are assessed, including a first-order model (the widely used Takács-model), in which the feasibility of using measured...... uncertainty of settler models can therefore propagate, and add to the uncertainties in prediction of any plant performance criteria. Here we present an assessment of the relative significance of secondary settling model performance in WWTP simulations. We perform a global sensitivity analysis (GSA) based...

Towards a consensus-based biokinetic model for green microalgae – The ASM-A

DEFF Research Database (Denmark)

Wágner, Dorottya Sarolta; Valverde Pérez, Borja; Sæbø, Mariann

2016-01-01

developed to predict microalgal growth. However, none of these models can effectively describe all the relevant processes when microalgal growth is coupled with nutrient removal and recovery from wastewaters. Here, we present a mathematical model developed to simulate green microalgal growth (ASM-A) using...... and substrate availability can introduce significant variability on parameter values for predicting the reaction rates for bulk nitrate and the intracellularly stored nitrogen state-variables, thereby requiring scenario specific model calibration. ASM-A was identified using standard cultivation medium...

Biokinetic modelling development and analysis of arsenic dissolution into the gastrointestinal tract using SAAM II

Science.gov (United States)

Perama, Yasmin Mohd Idris; Siong, Khoo Kok

2018-04-01

A mathematical model comprising 8 compartments were designed to describe the kinetic dissolution of arsenic (As) from water leach purification (WLP) waste samples ingested into the gastrointestinal system. A totally reengineered software system named Simulation, Analysis and Modelling II (SAAM II) was employed to aid in the experimental design and data analysis. As a powerful tool that creates, simulate and analyze data accurately and rapidly, SAAM II computationally creates a system of ordinary differential equations according to the specified compartmental model structure and simulates the solutions based upon the parameter and model inputs provided. The experimental design of in vitro DIN approach was applied to create an artificial gastric and gastrointestinal fluids. These synthetic fluids assay were produced to determine the concentrations of As ingested into the gastrointestinal tract. The model outputs were created based upon the experimental inputs and the recommended fractional transfer rates parameter. As a result, the measured and predicted As concentrations in gastric fluids were much similar against the time of study. In contrast, the concentrations of As in the gastrointestinal fluids were only similar during the first hour and eventually started decreasing until the fifth hours of study between the measured and predicted values. This is due to the loss of As through the fractional transfer rates of q2 compartment to corresponding compartments of q3 and q5 which are involved with excretion and distribution to the whole body, respectively. The model outputs obtained after best fit to the data were influenced significantly by the fractional transfer rates between each compartment. Therefore, a series of compartmental model created with the association of fractional transfer rates parameter with the aid of SAAM II provides better estimation that simulate the kinetic behavior of As ingested into the gastrointestinal system.

Bone and marrow dose modeling

International Nuclear Information System (INIS)

Stabin, Michael G.

2004-01-01

Nuclear medicine therapy is being used increasingly in the treatment of cancer (thyroid, leukemia/lymphoma with RIT, primary and secondary bone malignancies, and neuroblastomas). In all cases it is marrow toxicity that limits the amount of treatment that can be administered safely. Marrow dose calculations are more difficult than for many major organs because of the intricate association of bone and soft tissue elements. In RIT, there appears to be no consensus on how to calculate that dose accurately, or of individual patients ability to tolerate planned therapy. Available dose models are designed after an idealized average, healthy individual. Patient-specific methods are applied in evaluation of biokinetic data, and need to be developed for treatment of the physical data (dose conversion factors) as well: age, prior patient therapy, disease status. Contributors to marrow dose: electrons and photons

Dimer of the peptide cycle (Ar-Gly-Asp-D-Phe-Lys) radiolabeled with 99mTc for the integrin s over-expression image: formulation, biokinetics and dosimetry

International Nuclear Information System (INIS)

Ortiz A, Z.

2013-01-01

In breast cancer, α(v)β(3) and/or α(v)β(5) integrin s are over-expressed in both endothelial and tumour cells. Radiolabeled peptides based on the RGD (Arg-Gly-Asp) sequence are radiopharmaceuticals with high affinity and selectivity for those integrin s. The RGD-dimer peptide (E-[c(RGDfK)] 2 ) radiolabeled with 99m Tc has been reported as a radiopharmaceutical with 10-fold higher affinity for the α(v)β(3) integrin as compared to the RGD-monomer. EDDA (Ethylenediamine-N,N-diacetic acid) is a hydrophilic molecule that may favours renal excretion when used as coligand in the 99m Tc labelling of HYNIC-peptides and can easily be formulated in a lyophilized kit. Aim: Establish a biokinetic model for 99m Tc-EDDA/HYNIC-E-[c(RGDfK)] 2 prepared from lyophilized kits and evaluate the dosimetry as breast cancer imaging agent. Methods: 99m Tc labelling was performed by addition of sodium pertechnetate solution and 0.2 M phosphate buffer ph 7.0 to a lyophilized formulation containing E-[c(RGDfK)] 2 , EDDA, tricine, mannitol and stannous chloride. Radiochemical purity was evaluated by reversed phase HPLC and ITLC-SG analyses. Stability studies in human serum were carried out by size-exclusion HPLC. In-vitro cell uptake was tested using breast cancer cells (MCF7, T47D and MDA-MB-231) with blocked and non-blocked receptors. Biodistribution and tumour uptake were determined in MCF7 tumour-bearing nude mice with blocked and non-blocked receptors, and images were obtained using a micro-SPECT/CT. Whole-body images from seven healthy women were acquired at 1, 3, 6 and 24 h after 99m Tc-EDDA/HYNIC-E-[c(RGDfK)] 2 administration obtained with radiochemical purities of >94 %. Regions of interest (ROIs) were drawn around source organs on each time frame. Each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-EDDA/HYNIC-E-[c(RGDfK)] 2 time-activity curves in each organ in order to adjust the biokinetic model and to

Speciation and internal dosimetry: from chemical species to dosimetric models

International Nuclear Information System (INIS)

Paquet, F.; Frelon, S.; Cote, G.; Madic, C.

2004-01-01

Speciation studies refer to the distribution of species in a particular sample or matrix. These studies are necessary to improve the description, understanding and prediction of trace element kinetics and toxicity. In case of internal contamination with radionuclides, speciation studies could help to improve both the biokinetic and dosimetric models for radionuclides. There are different methods to approach the speciation of radionuclide in a biological system, depending on the degree of accuracy needed and the level of uncertainties accepted. Among them, computer modelling and experimental determination are complementary approaches. This paper describes what is known about speciation of actinides in blood, GI-tract, liver and skeleton and of their consequences in terms of internal dosimetry. The conclusion is that such studies provide very valuable data and should be targeted in the future on some specific tissues and biomolecules. (authors)

A Development of Domestic Food Chain Model Data for Chronic Effect Estimation of Off-site Consequence Analysis

Energy Technology Data Exchange (ETDEWEB)

Han, Seok-Jung; KEUM, Dong-Kwon; Jang, Seung-Cheol [KAERI, Daejeon (Korea, Republic of)

2015-05-15

The FCM includes complex transport phenomena of radiation materials on a biokinetic system of contaminated environments. An estimation of chronic health effects is a key part of the level 3 PSA (Probabilistic Safety Assessment), which depends on the FCM estimation from contaminated foods ingestion. A cultural ingestion habit of a local region and agricultural productions are different to the general features over worldwide scale or case by case. This is a reason to develop a domestic FCM data for the level 3 PSA. However, a generation of the specific FCM data is a complex process and under a large degree of uncertainty due to inherent biokinetic models. As a preliminary study, the present study focuses on an infrastructure development to generation of a specific FCM data. During this process, the features of FCM data to generate a domestic FCM data were investigated. Based on the insights obtained from this process, a specific domestic FCM data was developed. The present study was developed a domestic FCM data to estimate the chronic health effects of off-site consequence analysis. From this study, an insight was obtained, that a domestic FCM data is roughly 20 times higher than the MACCS2 defaults data. Based on this observation, it is clear that the specific chronic health effects of a domestic plant site should be considered in the off-site consequence analysis.

A Development of Domestic Food Chain Model Data for Chronic Effect Estimation of Off-site Consequence Analysis

International Nuclear Information System (INIS)

Han, Seok-Jung; KEUM, Dong-Kwon; Jang, Seung-Cheol

2015-01-01

The FCM includes complex transport phenomena of radiation materials on a biokinetic system of contaminated environments. An estimation of chronic health effects is a key part of the level 3 PSA (Probabilistic Safety Assessment), which depends on the FCM estimation from contaminated foods ingestion. A cultural ingestion habit of a local region and agricultural productions are different to the general features over worldwide scale or case by case. This is a reason to develop a domestic FCM data for the level 3 PSA. However, a generation of the specific FCM data is a complex process and under a large degree of uncertainty due to inherent biokinetic models. As a preliminary study, the present study focuses on an infrastructure development to generation of a specific FCM data. During this process, the features of FCM data to generate a domestic FCM data were investigated. Based on the insights obtained from this process, a specific domestic FCM data was developed. The present study was developed a domestic FCM data to estimate the chronic health effects of off-site consequence analysis. From this study, an insight was obtained, that a domestic FCM data is roughly 20 times higher than the MACCS2 defaults data. Based on this observation, it is clear that the specific chronic health effects of a domestic plant site should be considered in the off-site consequence analysis

Biokinetics and dosimetry of {sup 111}In-DOTA-NOC-ATE compared with {sup 111}In-DTPA-octreotide

Energy Technology Data Exchange (ETDEWEB)

Boubaker, Ariane; Prior, John O.; Champendal, Melanie; Bischof Delaloye, Angelika [Lausanne University Hospital, CHUV, Department of Nuclear Medicine, Lausanne (Switzerland); Willi, Jean-Pierre [University Hospital of Geneva, Department of Nuclear Medicine, Geneva 14 (Switzerland); Kosinski, Marek; Baechler, Sebastien [Lausanne University Hospital, Institute of Radiation Physics, Lausanne (Switzerland); Maecke, Helmut R. [University Hospital of Freiburg, Department of Nuclear Medicine, Freiburg (Germany); Ginj, Mihaela [University Health Network, Joint Department of Medical Imaging, Toronto, ON (Canada); Buchegger, Franz [Lausanne University Hospital, CHUV, Department of Nuclear Medicine, Lausanne (Switzerland); University Hospital of Geneva, Department of Nuclear Medicine, Geneva 14 (Switzerland)

2012-12-15

The biokinetics and dosimetry of {sup 111}In-DOTA-NOC-ATE (NOCATE), a high-affinity ligand of SSTR-2 and SSTR-5, and {sup 111}In-DTPA-octreotide (Octreoscan trademark, OCTREO) were compared in the same patients. Seventeen patients (10 men, 7 women; mean age 60 years), referred for an OCTREO scan for imaging of a neuroendocrine tumour (15), thymoma (1) or medullary thyroid carcinoma (1), agreed to undergo a second study with NOCATE. Whole-body anterior-posterior scans were recorded 0.5 (100 % reference scan), 4, 24 and 48 h (17 patients) and 120 h (5 patients) after injection. In 16 patients the OCTREO scan (178 {+-} 15 MBq) was performed 16 {+-} 5 days before the NOCATE scan (108 {+-} 14 MBq) with identical timing; 1 patient had the NOCATE scan before the OCTREO scan. Blood samples were obtained from 14 patients 5 min to 48 h after injection. Activities expressed as percent of the initial (reference) activity in the whole body, lung, kidney, liver, spleen and blood were fitted to biexponential or single exponential functions. Dosimetry was performed using OLINDA/EXM. Initial whole-body, lung and kidney activities were similar, but retention of NOCATE was higher than that of OCTREO. Liver and spleen uptakes of NOCATE were higher from the start (p < 0.001) and remained so over time. Whole-body activity showed similar {alpha} and {beta} half-lives, but the {beta} fraction of NOCATE was double that of OCTREO. Blood T{sub 1/2}{beta} for NOCATE was longer (19 vs. 6 h). As a result, the effective dose of NOCATE (105 {mu}Sv/MBq) exceeded that of OCTREO (52 {mu}Sv/MBq), and the latter result was similar to the ICRP 106 value of 54 {mu}Sv/MBq. Differential activity measurement in blood cells and plasma showed an average of <5 % of NOCATE and OCTREO attached to globular blood components. NOCATE showed a slower clearance from normal tissues and its effective dose was roughly double that of OCTREO. (orig.)

Evaluation of the various biokinetic models of liberation from characteristic deposition fraction of brazilian population sample

International Nuclear Information System (INIS)

Reis, Arlene A. dos; Cardoso, Joaquim C.S.; Lourenco, Maria Cristina

2005-01-01

The Publication 66 of International Commission of Radiological Protection (ICRP, 1994) presented the Human Respiratory tract Model that simulates the deposition and translocation of radioactive material in the air that penetrates in the body by inhalation. The main objective of this study is to evaluate the variation in fractional activity absorbed into blood when physiological and morphological parameters from Brazilian population are applied in the deposition model. The clearance model was implemented in the software Excel (version 2000) using a system of differential equations to solve simultaneous process of translocation and absorption of material deposited. After implementation were applied in the model fractional deposition calculated by deposition model using physiological and morphological parameters from Brazilian population. The results show that the variation in the clearance model depends on the material dissolution. For materials of rapid absorption, the variations calculated are not significant. Materials of moderate and slow absorption, presented variation greater than 20% in fractional activity absorbed into blood, depending on levels of exercise. (author)

Biodegradation of phenol with chromium(VI) reduction in an anaerobic fixed-biofilm process-Kinetic model and reactor performance

International Nuclear Information System (INIS)

Lin, Yen-Hui; Wu, Chih-Lung; Hsu, Chih-Hao; Li, Hsin-Lung

2009-01-01

A mathematical model system was derived to describe the simultaneous removal of phenol biodegradation with chromium(VI) reduction in an anaerobic fixed-biofilm reactor. The model system incorporates diffusive mass transport and double Monod kinetics. The model was solved using a combination of the orthogonal collocation method and Gear's method. A laboratory-scale column reactor was employed to validate the kinetic model system. Batch kinetic tests were conducted independently to evaluate the biokinetic parameters used in the model simulation. The removal efficiencies of phenol and chromium(VI) in an anaerobic fixed-biofilm process were approximately 980 mg/g and 910 mg/g, respectively, under a steady-state condition. In the steady state, model-predicted biofilm thickness reached up to 350 μm and suspended cells in the effluent were 85 mg cell/l. The experimental results agree closely with the results of the model simulations.

Dosimetric contribution of the organs of the I{sup 123}, I{sup 124} and I{sup 131} bio-kinetics in the dose estimate for euthyroid adults; Contribucion dosimetrica de los organos de la biocinetica de I{sup 123}, I{sup 124} y I{sup 131} en el estimado de dosis para adultos eutiroideos

Energy Technology Data Exchange (ETDEWEB)

Vasquez, A. M.; Rojas, A. R.; Castillo, D. C.; Idrogo, C. J.; Flores, U. H., E-mail: marvva@hotmail.com [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Ciudad Universitaria, Trujillo (Peru)

2011-10-15

Using the formalism MIRD and the representation of Crysty-Eckerman for the thyroid adult, is demonstrated that the dosimetric contributions of source organs of the biokinetics of the radiopharmaceuticals I{sup 123}, I{sup 124} and I{sup 131} (iodine) are not significant in the dose estimate. Therefore, the total absorbed dose by the gland is its auto-dose. Equally, the reported results do not present significant differences to the results found by the Marinelli scheme (auto-dose) for the thyroid represented by a sphere of 20 grams. (Author)

Application of the new ICRP respiratory tract model to inhaled plutonium nitrate using experimental biokinetic data

Energy Technology Data Exchange (ETDEWEB)

Birchall, A.; Bailey, M.R.; Jarvis, N.S. [National Radiological Protection Board, Chilton (United Kingdom)

1995-12-31

This paper describes the new ICRP respiratory tract model with particular reference to inhaled plutonium nitrate. The model is used to determine the absorption rates to blood for plutonium nitrate which when combined with the plutonium excretion functions were used to predict urinary excretion in man. The implications of the new model for radiological protection are discussed. (UK).

High Throughput PBPK: Evaluating EPA's Open-Source Data and Tools for Dosimetry and Exposure Reconstruction (SOT)

Science.gov (United States)

To address this need, new tools have been created for characterizing, simulating, and evaluating chemical biokinetics. Physiologically-based pharmacokinetic (PBPK) models provide estimates of chemical exposures that produce potentially hazardous tissue concentrations, while tissu...

Modeling arsenite oxidation by chemoautotrophic Thiomonas arsenivorans strain b6 in a packed-bed bioreactor

Energy Technology Data Exchange (ETDEWEB)

Dastidar, Aniruddha, E-mail: andy.dastidar@ky.gov [USEPA Research Participant, Division of Water, Frankfort, KY 40601 (United States); Wang, Yi-Tin, E-mail: ywang@engr.uky.edu [Department of Civil Engineering, University of Kentucky, Lexington (United States)

2012-08-15

Arsenic is a major toxic pollutant of concern for the human health. Biological treatment of arsenic contaminated water is an alternative strategy to the prevalent conventional treatments. The biological treatment involves a pre-oxidation step transforming the most toxic form of arsenic, As (III), to the least toxic form, As (V), respectively. This intermediate process improves the overall efficiency of total arsenic removal from the contaminated water. As (III) oxidation by the chemoautotrophic bacterium Thiomonas arsenivorans strain b6 was investigated in a fixed-film reactor under variable influent As (III) concentrations (500-4000 mg/L) and hydraulic residence times (HRTs) (0.2-1 day) for a duration of 137 days. During the entire operation, seven steady-state conditions were obtained with As (III) oxidation efficiency ranging from 48.2% to 99.3%. The strong resilience of the culture was exhibited by the recovery of the bioreactor from an As (III) overloading of 5300 {+-} 400 mg As (III)/L day operated at a HRT of 0.2 day. An arsenic mass balance revealed that As (III) was mainly oxidized to As (V) with unaccounted arsenic ({<=} 4%) well within the analytical error of measurement. A modified Monod flux expression was used to determine the biokinetic parameters by fitting the model against the observed steady-state flux data obtained from operating the bioreactor under a range of HRTs (0.2-1 day) and a constant influent As (III) concentration of 500 mg/L. Model parameters, k = 0.71 {+-} 0.1 mg As (III)/mg cells h, and K{sub s} = 13.2 {+-} 2.8 mg As (III)/L were obtained using a non-linear estimation routine and employing the Marquardt-Levenberg algorithm. Sensitivity analysis revealed k to be more sensitive to model simulations of As (III) oxidation under steady-state conditions than parameter K{sub s}. -- Highlights: Black-Right-Pointing-Pointer As (III) oxidation. Black-Right-Pointing-Pointer Biokinetic parameters. Black-Right-Pointing-Pointer Model validation

A model for the bioaccumulation of 99Tc in lobsters (Homarus gammarus) from the West Cumbrian coast

International Nuclear Information System (INIS)

Olsen, Y.S.; Vives i Batlle, J.

2003-01-01

A biokinetic model is presented that simulates the uptake and release of 99 Tc by the European lobster (Homarus gammarus). This organism is of significant radioecological interest since lobsters, in contrast to most other organisms, have a high affinity for 99 Tc. The model is designed to represent annually averaged 99 Tc concentrations in lobsters from the Cumbrian coast, where significant levels of 99 Tc have been released under authorisation by the nuclear fuel reprocessing plant at BNFL Sellafield. This paper describes the construction of the model, how it was calibrated using data from published literature, and preliminary results indicating that model output agrees well with the available monitoring data. Given that this model successfully combines laboratory and field data, this research could potentially make a significant contribution to the field, as, to date, it has been difficult to predict and explain concentrations of 99 Tc in lobsters

Predicting patient exposure to nickel released from cardiovascular devices using multi-scale modeling.

Science.gov (United States)

Saylor, David M; Craven, Brent A; Chandrasekar, Vaishnavi; Simon, David D; Brown, Ronald P; Sussman, Eric M

2018-04-01

Many cardiovascular device alloys contain nickel, which if released in sufficient quantities, can lead to adverse health effects. However, in-vivo nickel release from implanted devices and subsequent biodistribution of nickel ions to local tissues and systemic circulation are not well understood. To address this uncertainty, we have developed a multi-scale (material, tissue, and system) biokinetic model. The model links nickel release from an implanted cardiovascular device to concentrations in peri-implant tissue, as well as in serum and urine, which can be readily monitored. The model was parameterized for a specific cardiovascular implant, nitinol septal occluders, using in-vitro nickel release test results, studies of ex-vivo uptake into heart tissue, and in-vivo and clinical measurements from the literature. Our results show that the model accurately predicts nickel concentrations in peri-implant tissue in an animal model and in serum and urine of septal occluder patients. The congruity of the model with these data suggests it may provide useful insight to establish nickel exposure limits and interpret biomonitoring data. Finally, we use the model to predict local and systemic nickel exposure due to passive release from nitinol devices produced using a wide range of manufacturing processes, as well as general relationships between release rate and exposure. These relationships suggest that peri-implant tissue and serum levels of nickel will remain below 5 μg/g and 10 μg/l, respectively, in patients who have received implanted nitinol cardiovascular devices provided the rate of nickel release per device surface area does not exceed 0.074 μg/(cm 2  d) and is less than 32 μg/d in total. The uncertainty in whether in-vitro tests used to evaluate metal ion release from medical products are representative of clinical environments is one of the largest roadblocks to establishing the associated patient risk. We have developed and validated a multi

Evaluation of the absorbed dose during studies of the renal function due to I123 / I131 (hippuran) and In111 (DTPA)

International Nuclear Information System (INIS)

Vasquez, M.; Castillo, C.; Sarachaga, R.; Rojas, R.; Zelada, L.; Melendez, J.; Gomez, M.; Diaz, E.

2014-08-01

Using the methodology MIRD and representation Cristy-Eckerman for kidneys, bladder, and whole body as organs of the bio-kinetics of I 123 / I 131 (hippuran) and the In 111 (D PTA), the absorbed dose for studies of the renal function of adults due to the I 123 is 0,0071 mGy/MBq where 88.16% corresponds to its auto-dose and 11,96% to the organs of their bio-kinetics; while for the I 131 their dose is 0,032 mGy/MBq where 95,03% corresponds to its auto-dose and 4,97% to the organs of their bio-kinetics. For the In 111 their dose is 0,0168 mGy/MBq where 71,68% corresponds to their auto-dose and 28,32% to the organs of their bio-kinetics. In all the cases the dosimetric contributions of the organs of the bio-kinetics (whole body and urinary bladder) are very significant, and this fundamentally is due to the photons of the whole body. (Author)

Evaluation of the absorbed dose during studies of the renal function due to I{sup 123} / I{sup 131} (hippuran) and In{sup 111} (DTPA); Evaluacion de la dosis absorbida durante estudios de la funcion renal debido a I{sup 123} / I{sup 131} (hippuran) e In{sup 111} (DPTA)

Energy Technology Data Exchange (ETDEWEB)

Vasquez, M.; Castillo, C.; Sarachaga, R.; Rojas, R.; Zelada, L.; Melendez, J.; Gomez, M. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Ciudad Universitaria, Trujillo (Peru); Diaz, E., E-mail: marvva@hotmail.com [Universidade Federal do Rio Grande do Sul, Av. Paulo Gamma 110, Bairro Farropilhas, Porto Alegre, RS 90040-060 (Brazil)

2014-08-15

Using the methodology MIRD and representation Cristy-Eckerman for kidneys, bladder, and whole body as organs of the bio-kinetics of I{sup 123} / I{sup 131} (hippuran) and the In{sup 111} (D PTA), the absorbed dose for studies of the renal function of adults due to the I{sup 123} is 0,0071 mGy/MBq where 88.16% corresponds to its auto-dose and 11,96% to the organs of their bio-kinetics; while for the I{sup 131} their dose is 0,032 mGy/MBq where 95,03% corresponds to its auto-dose and 4,97% to the organs of their bio-kinetics. For the In{sup 111} their dose is 0,0168 mGy/MBq where 71,68% corresponds to their auto-dose and 28,32% to the organs of their bio-kinetics. In all the cases the dosimetric contributions of the organs of the bio-kinetics (whole body and urinary bladder) are very significant, and this fundamentally is due to the photons of the whole body. (Author)

Biokinetics and dosimetry of 99m Tc-EDDA/HYNIC-[Lys3]-bombesin in humans: imaging of GRP receptors

International Nuclear Information System (INIS)

Santos C, C.L.; Ferro F, G.; Murphy, C.A de; Cardena, E.; Pichardo R, P.

2007-01-01

Full text: Bombesin (BN) receptor subtype 2 (GRP-r) is over-expressed on various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently we reported the 99- mTc-EDDA/HYNIC-[Lys 3 ]-Bombesin ( 99m Tc-HYNIC-BN) complex as a new radiopharmaceutical with high stability in human serum, specific cell GRP-receptor binding and rapid internalization. The aim of this study was to evaluate the 99m Tc-HYNIC-BN biokinetics and dosimetry in 5-healthy and 3-breast cancer women. Whole-body images were acquired at 20, 90, 180 min and 24 h after 99m Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source' organs on each time frame. The same set of ROIs was used for all 8 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-HYNIC-BN time activity curves in each organ, to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed a rapid radiopharmaceutical blood clearance with predominantly renal excretion and minimal hepatobiliary elimination. 99m Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in breast cancer lesions and well differentiated from GRP-r expression in lungs and airways with normal GRP-r density (ratio 3:1). The equivalent doses for a study using 370 MBq were 7.38±1.68, 0.59±0.08, 2.07±0.60, 0.58±0.1, 0.75±0.09 and 0.43±0.07 mSv for kidneys, liver, lungs, ovaries, pancreas and red marrow respectively. The effective dose was 1.64±0.25 mSv which is comparable with the doses known for most of the 99m Tc radiopharmaceutical studies in nuclear medicine. (Author)

Microdistribution of uranium in kidney using alpha radiography of body animal

International Nuclear Information System (INIS)

Cebrian, D.; Morcillo, M. A.

2006-01-01

The radiation dose estimation after an internal contamination by a radionuclide requires the use of biokinetic and dosimetric models, which provide the tools for its calculation. The detailed knowledge of the biokinetic behaviour of the corresponding radionuclide is needed in order to build these models. Laboratory animals are employed to get this knowledge. In this context, the use of appropriate radioactivity measurement techniques is important to follow the distribution of the radionuclide within the organism. In this study an animal model of rat treated with uranyl citrate has been used. Sections of the whole animal are made at different times post-administration, and alpha autoradiography is performed with the slices in order to study the microdistribution of the uranium in the kidney. the utility of the alpha autoradiography whole body animal sections for the detailed study of the alpha emitters biodistribution is shown. (Author) 16 refs

Dosimetry and effects of fetal irradiation from incorporated radionuclides

International Nuclear Information System (INIS)

Harrison, J.D.; Coffigny, H.; Henshaw, D.L.

1993-01-01

An important aspect of the assessment of risks from incorporated radionuclides is the possibility of intakes by pregnant women and in utero exposure of the developing fetus. The overall objective of the project is to provide experimental data for the development of dosimetric models and assessment of risk. Studies include measurements of 210 Po and 239/240 Pu in human fetal tissues and placentae, animal studies of the biokinetics of radionuclide transfer and effects. Animal biokinetic studies concentrate on comparing the uptake and distribution of Po-210, Pu-238 and Am-241 in rats and guinea pigs for different exposure conditions. The data are used, together with the human data, to develop dosimetric models. Objectives and results of the three contributions to the project for the reporting period are presented. (R.P.) 4 figs., 1 tab

Uncertainty analysis in WWTP model applications: a critical discussion using an example from design

DEFF Research Database (Denmark)

Sin, Gürkan; Gernaey, Krist; Neumann, Marc B.

2009-01-01

of design performance criteria differs significantly. The implication for the practical applications of uncertainty analysis in the wastewater industry is profound: (i) as the uncertainty analysis results are specific to the framing used, the results must be interpreted within the context of that framing......This study focuses on uncertainty analysis of WWTP models and analyzes the issue of framing and how it affects the interpretation of uncertainty analysis results. As a case study, the prediction of uncertainty involved in model-based design of a wastewater treatment plant is studied. The Monte...... to stoichiometric, biokinetic and influent parameters; (2) uncertainty due to hydraulic behaviour of the plant and mass transfer parameters; (3) uncertainty due to the combination of (1) and (2). The results demonstrate that depending on the way the uncertainty analysis is framed, the estimated uncertainty...

Ab initio chemical safety assessment: A workflow based on exposure considerations and non-animal methods

OpenAIRE

Berggren, Elisabet; White, Andrew; Ouedraogo, Gladys; Paini, Alicia; Richarz, Andrea-Nicole; Bois, Frederic Y.; Exner, Thomas; Leite, Sofia; Grunsven, Leo A. van; Worth, Andrew; Mahony, Catherine

2017-01-01

Highlights • A workflow for an exposure driven chemical safety assessment to avoid animal testing. • Hypothesis based on existing data, in silico modelling and biokinetic considerations. • A tool to inform targeted and toxicologically relevant in vitro testing.

Measurement and modelling in anthropo-radiometry

International Nuclear Information System (INIS)

Carlan, Loic de

2011-01-01

In this HDR (Accreditation to supervise researches) report, the author gives an overview of his research activities, gives a summary of his research thesis (feasibility study of an actinide measurement system in the case of lungs), and proposes a research report on the different aspects of anthropo-radiometric measurement: context (principles, significance, sampling phantoms), development of digital phantoms (software presentation and validation), interface development and validation, application to actinide measurement in lung, taking biokinetic data into account for anthropo-radiometric measurement

Biokinetics of copper in black-banded rainbowfish (Melanotaenia nigrans) tolerant to elevated copper concentrations, using the radioisotope 64Cu

International Nuclear Information System (INIS)

Gale, S.; Jeffree, R.; Smith, S.; Lim, R.

2000-01-01

Full text: For over 40 years black-banded rainbowfish (Melanotaenia nigrans) living in the East Branch of the Finniss River, Northern Territory have been exposed to elevated copper concentrations due to mine waste from the Rum Jungle uranium/copper mine. In the 1970s prior to remediation of the mine, fish kills were observed along the length of the East Branch. While copper concentrations remain comparatively high (up to 2000 μg/L) in the East Branch since remediation of the mine site, M. nigrans have been observed in the area. It was, therefore, hypothesised that due to selective pressure of lethal exposure, the population of black-banded rainbowfish in the East Branch have developed a tolerance to elevated copper concentrations. This project aimed to demonstrate copper tolerance and evaluate possible mechanism(s). In May 2000, fish were collected from the East Branch (exposed fish) and from a catchment previously unexposed to elevated metal concentrations (reference fish). The 96-hour EC 50 , fish imbalance (i.e. the concentration of copper that affects 50% of fish over 96 hours) for the exposed fish was over 8 times higher than the reference fish. Using the radioisotope, 64 Cu, the biokinetics of newly accumulated copper was traced in exposed and reference fish at low and elevated copper concentrations. The uptake rate, and therefore body burden, were significantly (p=0.000) lower in exposed fish, at both low and elevated copper concentrations compared to reference fish. Possible mechanisms of reducing copper uptake will be discussed. Tolerance was not lost when fish were maintained in relatively low copper concentrations in the laboratory. Also, the two populations of fish were genetically dissimilar based on allozyme analysis, which suggests that the mechanism is genetically mediated. The outcome of this project will be important in assisting accurate risk assessment and the development of environmental management strategies for the conservation of biota. The

A model for the bioaccumulation of {sup 99}Tc in lobsters (Homarus gammarus) from the West Cumbrian coast

Energy Technology Data Exchange (ETDEWEB)

Olsen, Y.S.; Vives i Batlle, J. E-mail: jordi.vives@westlakes.ac.uk

2003-07-01

A biokinetic model is presented that simulates the uptake and release of {sup 99}Tc by the European lobster (Homarus gammarus). This organism is of significant radioecological interest since lobsters, in contrast to most other organisms, have a high affinity for {sup 99}Tc. The model is designed to represent annually averaged {sup 99}Tc concentrations in lobsters from the Cumbrian coast, where significant levels of {sup 99}Tc have been released under authorisation by the nuclear fuel reprocessing plant at BNFL Sellafield. This paper describes the construction of the model, how it was calibrated using data from published literature, and preliminary results indicating that model output agrees well with the available monitoring data. Given that this model successfully combines laboratory and field data, this research could potentially make a significant contribution to the field, as, to date, it has been difficult to predict and explain concentrations of {sup 99}Tc in lobsters.

Exposure implications for uranium aerosols formed at a new laser enrichment facility: application of the ICRP Respiratory Tract and Systemic Model

Energy Technology Data Exchange (ETDEWEB)

Ansorbolo, E.; Hodgson, A.; Stradling, G.N.; Hodgson, S.; Metivier, H.; Henge-Napoli, M.H.; Jarvis, N.S.; Birchall, A

1998-07-01

A pilot enrichment facility developed in France employs laser technology. The development of this process has resulted in three different types of aerosols identified as variable mixtures of U{sub metal}+ UO{sub 2} and U{sub 3}O{sub 8}. A procedure is described for assessing intakes and doses after inhalation of these dusts using site and material specific data in conjunction with the most recent ICRP biokinetic models. It is concluded that exposure control could be based on either radiotoxicity or chemical toxicity and that chest monitoring and urine assay could be useful, provided that measurements are made soon after a known acute intake. (author)

Time-integrated activity coefficient estimation for radionuclide therapy using PET and a pharmacokinetic model: A simulation study on the effect of sampling schedule and noise

Energy Technology Data Exchange (ETDEWEB)

Hardiansyah, Deni [Medical Radiation Physics/Radiation Protection, Medical Faculty Mannheim, Universitätsmedizin Mannheim, Heidelberg University, Mannheim 68167, Germany and Department of Radiation Oncology, Medical Faculty Mannheim, Universitätsmedizin Mannheim, Heidelberg University, Mannheim 68167 (Germany); Guo, Wei; Glatting, Gerhard, E-mail: gerhard.glatting@medma.uni-heidelberg.de [Medical Radiation Physics/Radiation Protection, Medical Faculty Mannheim, Universitätsmedizin Mannheim, Heidelberg University, Mannheim 68167 (Germany); Kletting, Peter [Department of Nuclear Medicine, Ulm University, Ulm 89081 (Germany); Mottaghy, Felix M. [Department of Nuclear Medicine, University Hospital, RWTH Aachen University, Aachen 52074, Germany and Department of Nuclear Medicine, Maastricht University Medical Center MUMC+, Maastricht 6229 (Netherlands)

2016-09-15

Purpose: The aim of this study was to investigate the accuracy of PET-based treatment planning for predicting the time-integrated activity coefficients (TIACs). Methods: The parameters of a physiologically based pharmacokinetic (PBPK) model were fitted to the biokinetic data of 15 patients to derive assumed true parameters and were used to construct true mathematical patient phantoms (MPPs). Biokinetics of 150 MBq {sup 68}Ga-DOTATATE-PET was simulated with different noise levels [fractional standard deviation (FSD) 10%, 1%, 0.1%, and 0.01%], and seven combinations of measurements at 30 min, 1 h, and 4 h p.i. PBPK model parameters were fitted to the simulated noisy PET data using population-based Bayesian parameters to construct predicted MPPs. Therapy simulations were performed as 30 min infusion of {sup 90}Y-DOTATATE of 3.3 GBq in both true and predicted MPPs. Prediction accuracy was then calculated as relative variability v{sub organ} between TIACs from both MPPs. Results: Large variability values of one time-point protocols [e.g., FSD = 1%, 240 min p.i., v{sub kidneys} = (9 ± 6)%, and v{sub tumor} = (27 ± 26)%] show inaccurate prediction. Accurate TIAC prediction of the kidneys was obtained for the case of two measurements (1 and 4 h p.i.), e.g., FSD = 1%, v{sub kidneys} = (7 ± 3)%, and v{sub tumor} = (22 ± 10)%, or three measurements, e.g., FSD = 1%, v{sub kidneys} = (7 ± 3)%, and v{sub tumor} = (22 ± 9)%. Conclusions: {sup 68}Ga-DOTATATE-PET measurements could possibly be used to predict the TIACs of {sup 90}Y-DOTATATE when using a PBPK model and population-based Bayesian parameters. The two time-point measurement at 1 and 4 h p.i. with a noise up to FSD = 1% allows an accurate prediction of the TIACs in kidneys.

Implementation of the NCRP wound model for interpretation of bioassay data for intake of radionuclides through contaminated wounds

International Nuclear Information System (INIS)

Ishigure, Nobuhito

2009-01-01

Emergency response preparedness for radiological accidents involving wound contamination has become more important, considering the current extending tendency in the nuclear industry related to the nuclear fuel cycle. The US National Council on Radiation Protection and Measurements (NCRP) proposed a biokinetic and dosimetric model for the intake of radionuclides through contaminated wounds in 2007. The present paper describes the implementation of this NCRP wound model for the prediction of systemic behaviour of some important radioactive elements encountered in workplaces related to the nuclear industry. The NCRP wound model was linked to the current ICRP systemic model at each blood compartment and simultaneous differential equations for the content of radioactivity in each compartment and excreta were solved with the Runge-Kutta method. The results of the calculation of wound, whole-body or specific organ retention and daily urinary or faecal excretion rate of some selected elements will be useful for the interpretation of bioassay data and dose assessment for cases of wound contamination. (author)

The application of equilibrium models to incidence situations using the example of the exposure pathway human milk

International Nuclear Information System (INIS)

Steiner, Martin; Karcher, Klaus; Nosske, Dietmar

2012-01-01

The radiation exposure after a short-term release of radioactive substances is often calculated assuming equilibrium conditions. An example is that of the German Incident Calculation Bases for nuclear power plants with pressurized water reactors. Here, the contamination of human milk is calculated using transfer factors. Applying this equilibrium model to incident situations raises the question whether baby's radiation exposure is adequately assessed. This contribution shows that compliance with the relevant dose limits of paragraph 49 of the German Radiation Protection Ordinance is ensured for design basis accidents on the assumption that the hypothetical breastfeeding period starts at the beginning of the activity release. Comparative analyses were performed against the biokinetic models applied by ICRP for radiation protection purposes, taking the reference nuclides 137 Cs, 90 Sr, 131 I, 241 Am and long-lived plutonium isotopes as examples. (orig.)

Binary mixtures of mercury/ selenium, and lead/selenium

African Journals Online (AJOL)

Physiologically-based biokinetic models have been developed for predicting simultaneously the Absorption, Distribution, Metabolism and Elimination (ADME) properties of lead (Pb) and selenium (Se), and mercury (Hg) and selenium in a number of target tissues of humans. This was done for three population groups, ...

Retention of tritium in reference persons: a metabolic model. Derivation of parameters and application of the model to the general public and to workers

International Nuclear Information System (INIS)

Galeriu, D; Melintescu, A

2010-01-01

Tritium ( 3 H) is a radioactive isotope of hydrogen that is ubiquitous in environmental and biological systems. Following debate on the human health risk from exposure to tritium, there have been claims that the current biokinetic model recommended by the International Commission on Radiological Protection (ICRP) may underestimate tritium doses. A new generic model for tritium in mammals, based on energy metabolism and body composition, together with all its input data, has been described in a recent paper and successfully tested for farm and laboratory mammals. That model considers only dietary intake of tritium and was extended to humans. This paper presents the latest development of the human model with explicit consideration of brain energy metabolism. Model testing with human experimental data on organically bound tritium (OBT) in urine after tritiated water (HTO) or OBT intakes is presented. Predicted absorbed doses show a moderate increase for OBT intakes compared with doses recommended by the ICRP. Infants have higher tritium retention-a factor of 2 longer than the ICRP estimate. The highest tritium concentration is in adipose tissue, which has a very low radiobiological sensitivity. The ranges of uncertainty in retention and doses are investigated. The advantage of the new model is its ability to be applied to the interpretation of bioassay data.

Retention of tritium in reference persons: a metabolic model. Derivation of parameters and application of the model to the general public and to workers

Energy Technology Data Exchange (ETDEWEB)

Galeriu, D; Melintescu, A, E-mail: galdan@ifin.nipne.r, E-mail: dangaler@yahoo.co [' Horia Hulubei' National Institute for Physics and Nuclear Engineering, Department of Life and Environmental Physics, 407 Atomistilor Street, Bucharest-Magurele, POB MG-6, RO-077125 (Romania)

2010-09-15

Tritium ({sup 3}H) is a radioactive isotope of hydrogen that is ubiquitous in environmental and biological systems. Following debate on the human health risk from exposure to tritium, there have been claims that the current biokinetic model recommended by the International Commission on Radiological Protection (ICRP) may underestimate tritium doses. A new generic model for tritium in mammals, based on energy metabolism and body composition, together with all its input data, has been described in a recent paper and successfully tested for farm and laboratory mammals. That model considers only dietary intake of tritium and was extended to humans. This paper presents the latest development of the human model with explicit consideration of brain energy metabolism. Model testing with human experimental data on organically bound tritium (OBT) in urine after tritiated water (HTO) or OBT intakes is presented. Predicted absorbed doses show a moderate increase for OBT intakes compared with doses recommended by the ICRP. Infants have higher tritium retention-a factor of 2 longer than the ICRP estimate. The highest tritium concentration is in adipose tissue, which has a very low radiobiological sensitivity. The ranges of uncertainty in retention and doses are investigated. The advantage of the new model is its ability to be applied to the interpretation of bioassay data.

Excretion of radionuclides in human breast milk after nuclear medicine examinations. Biokinetic and dosimetric data and recommendations on breastfeeding interruption

Energy Technology Data Exchange (ETDEWEB)

Leide-Svegborn, Sigrid; Ahlgren, Lars; Mattsson, Soeren [Lund University, Department of Medical Radiation Physics, Skaane University Hospital, Malmoe (Sweden); Johansson, Lennart [Umeaa University, Department of Radiation Sciences, Umeaa (Sweden)

2016-05-15

To review early recommendations and propose guidelines for breastfeeding interruption after administration of radiopharmaceuticals, based on additional biokinetic and dosimetric data. Activity concentrations in breast milk from 53 breastfeeding patients were determined. The milk was collected at various times after administration of 16 different radiopharmaceuticals. The fraction of the activity administered to the mother excreted in the breast milk, the absorbed doses to various organs and tissues and the effective dose to the infant were estimated. The fraction of the administered activity excreted per millilitre of milk varied widely from 10{sup -10} to 10{sup -3} MBq/MBq administered. For {sup 99m}Tc-labelled radiopharmaceuticals, the total fraction of the administered activity excreted in the milk varied from 0.0057 % for {sup 99m}Tc-labelled red blood cells (RBC) to 19 % for {sup 99m}Tc-pertechnetate. The effective dose to an infant per unit activity administered to the mother ranged from 6.7 x 10{sup -6} mSv/MBq for {sup 99m}Tc-labelled RBC to 3.6 x 10{sup -2} mSv/MBq for {sup 99m}Tc-pertechnetate. For the other radiopharmaceuticals, the total fraction of administered activity excreted in the milk varied from 0.018 % ({sup 51}Cr-EDTA) to 48 % ({sup 131}I-NaI). The effective dose ranged from 5.6 x 10{sup -5} mSv{sub infant}/MBq{sub mother} ({sup 51}Cr-EDTA) to 106 mSv{sub infant}/MBq{sub mother} ({sup 131}I-NaI). Based on an effective dose limit of 1 mSv to the infant and a typical administered activity, we recommend cessation of breastfeeding for {sup 131}I-NaI and interruption of feeding for 12 h for {sup 125}I-iodohippurate, {sup 131}I-iodohippurate, {sup 99m}Tc-pertechnetate and {sup 99m}Tc-MAA. During this 12-h period all breast milk should be expressed at least three times and discarded. For the other radiopharmaceuticals included in this study, no interruption of breastfeeding is necessary. (orig.)

Biokinetics and dosimetry of {sup 99m} Tc-EDDA/HYNIC-[Lys{sup 3}]-bombesin in humans: imaging of GRP receptors

Energy Technology Data Exchange (ETDEWEB)

Santos C, C.L.; Ferro F, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Murphy, C.A de [INCMNSZ, 14000 Mexico D.F. (Mexico); Cardena, E.; Pichardo R, P. [Departamento de Medicina Nuclear, Oncologia Centro Medico Siglo XXI, Mexico D.F. (Mexico)

2007-07-01

Full text: Bombesin (BN) receptor subtype 2 (GRP-r) is over-expressed on various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently we reported the {sup 99-}mTc-EDDA/HYNIC-[Lys{sup 3}]-Bombesin ({sup 99m}Tc-HYNIC-BN) complex as a new radiopharmaceutical with high stability in human serum, specific cell GRP-receptor binding and rapid internalization. The aim of this study was to evaluate the {sup 99m}Tc-HYNIC-BN biokinetics and dosimetry in 5-healthy and 3-breast cancer women. Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source' organs on each time frame. The same set of ROIs was used for all 8 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time activity curves in each organ, to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Images showed a rapid radiopharmaceutical blood clearance with predominantly renal excretion and minimal hepatobiliary elimination. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in breast cancer lesions and well differentiated from GRP-r expression in lungs and airways with normal GRP-r density (ratio 3:1). The equivalent doses for a study using 370 MBq were 7.38{+-}1.68, 0.59{+-}0.08, 2.07{+-}0.60, 0.58{+-}0.1, 0.75{+-}0.09 and 0.43{+-}0.07 mSv for kidneys, liver, lungs, ovaries, pancreas and red marrow respectively. The effective dose was 1.64{+-}0.25 mSv which is comparable with the doses known for most of the {sup 99m}Tc radiopharmaceutical studies in nuclear medicine. (Author)

A Common Decision of Compartmental Models on the Base of Laplace Transform and Retain Function Concept

International Nuclear Information System (INIS)

Dimitrov, L.; Tzvetkova, A.; Nikolov, A.

1997-01-01

The compartmental models have a variety of applications in the analysis of the transport of radioactive and non-radioactive material in complex systems as atmosphere, hydrosphere, food chains, human body. The analysis of the biokinetic behaviour of the radioactive material into a human body gives a possibility for correct assessment of the dose from internal irradiation. Skrable has given a decision of non-cyclic linear compartmental models in case of a single intake of material in the compartments as an initial condition. The main purpose of our article is to write down a procedure for analysis of a general compartmental model in case of continuous intake of material into the compartments. This procedure is related to retain function concept and had developed on the base of Laplace transform. On the base on the proposed procedure a non-cyclic linear compartmental model decisions are given in case of both a single and a continuous intake. The Laplace images of cyclic and circular linear compartmental model decisions and their originals in some cases are given too. (author)

Transfer of alkaline earth elements in mothers' milk and doses from 45Ca, 90Sr and 226Ra

International Nuclear Information System (INIS)

Smith, T.J.; Phipps, A.W.; Fell, T.P.; Harrison, J.D.

2003-01-01

An international programme of work is currently under way to develop methods for calculating doses to infants from ingestion of radionuclides present in mothers' milk. This paper considers the special case of the alkaline earth elements. Models have been developed for 45 Ca, 90 Sr and 226 Ra and the sensitivity of results to various changes in parameter values is discussed. A complication when calculating doses from intakes of radium is that the International Commission on Radiological Protection has previously recommended that doses from decay products of radium should be calculated using element-specific biokinetic models (so-called independent biokinetics). An extension of this method to the models for breastfeeding is proposed. Preliminary estimates of the doses received by the infant for a number of maternal intake scenarios show that doses to the infant can exceed the corresponding adult dose, such as for 45 Ca (ratio = 3.1) while, in other cases such as 90 Sr, the infant dose can be a significant fraction of the adult dose. (author)

Transfer of alkaline earth elements in mothers' milk and doses from {sup 45}Ca, {sup 90}Sr and {sup 226}Ra

Energy Technology Data Exchange (ETDEWEB)

Smith, T.J.; Phipps, A.W.; Fell, T.P.; Harrison, J.D

2003-07-01

An international programme of work is currently under way to develop methods for calculating doses to infants from ingestion of radionuclides present in mothers' milk. This paper considers the special case of the alkaline earth elements. Models have been developed for {sup 45}Ca, {sup 90}Sr and {sup 226}Ra and the sensitivity of results to various changes in parameter values is discussed. A complication when calculating doses from intakes of radium is that the International Commission on Radiological Protection has previously recommended that doses from decay products of radium should be calculated using element-specific biokinetic models (so-called independent biokinetics). An extension of this method to the models for breastfeeding is proposed. Preliminary estimates of the doses received by the infant for a number of maternal intake scenarios show that doses to the infant can exceed the corresponding adult dose, such as for {sup 45}Ca (ratio = 3.1) while, in other cases such as {sup 90}Sr, the infant dose can be a significant fraction of the adult dose. (author)

Assessing the reliability of dose coefficients for exposure to radioiodine by members of the public, accounting for dosimetric and risk model uncertainties.

Science.gov (United States)

Puncher, M; Zhang, W; Harrison, J D; Wakeford, R

2017-06-26

Assessments of risk to a specific population group resulting from internal exposure to a particular radionuclide can be used to assess the reliability of the appropriate International Commission on Radiological Protection (ICRP) dose coefficients used as a radiation protection device for the specified exposure pathway. An estimate of the uncertainty on the associated risk is important for informing judgments on reliability; a derived uncertainty factor, UF, is an estimate of the 95% probable geometric difference between the best risk estimate and the nominal risk and is a useful tool for making this assessment. This paper describes the application of parameter uncertainty analysis to quantify uncertainties resulting from internal exposures to radioiodine by members of the public, specifically 1, 10 and 20-year old females from the population of England and Wales. Best estimates of thyroid cancer incidence risk (lifetime attributable risk) are calculated for ingestion or inhalation of 129 I and 131 I, accounting for uncertainties in biokinetic model and cancer risk model parameter values. These estimates are compared with the equivalent ICRP derived nominal age-, sex- and population-averaged estimates of excess thyroid cancer incidence to obtain UFs. Derived UF values for ingestion or inhalation of 131 I for 1 year, 10-year and 20-year olds are around 28, 12 and 6, respectively, when compared with ICRP Publication 103 nominal values, and 9, 7 and 14, respectively, when compared with ICRP Publication 60 values. Broadly similar results were obtained for 129 I. The uncertainties on risk estimates are largely determined by uncertainties on risk model parameters rather than uncertainties on biokinetic model parameters. An examination of the sensitivity of the results to the risk models and populations used in the calculations show variations in the central estimates of risk of a factor of around 2-3. It is assumed that the direct proportionality of excess thyroid cancer

131I-SPGP internal dosimetry: animal model and human extrapolation

International Nuclear Information System (INIS)

Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soprani, Juliana; Santos, Raquel Gouvea dos; Figueiredo, Suely Gomes de

2009-01-01

Scorpaena plumieri is commonly called moreia-ati or manganga and is the most venomous and one of the most abundant fish species of the Brazilian coast. Soprani 2006, demonstrated that SPGP - an isolated protein from S. plumieri fish- possess high antitumoral activity against malignant tumours and can be a source of template molecules for the development (design) of antitumoral drugs. In the present work, Soprani's 125 ISPGP biokinetic data were treated by MIRD formalism to perform Internal Dosimetry studies. Absorbed doses due to the 131 I-SPGP uptake were determinate in several organs of mice, as well as in the implanted tumor. Doses obtained for animal model were extrapolated to humans assuming a similar ratio for various mouse and human tissues. For the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from 131 I were considered. (author)

The application of equilibrium models to incidence situations using the example of the exposure pathway human milk

Energy Technology Data Exchange (ETDEWEB)

Steiner, Martin; Karcher, Klaus; Nosske, Dietmar [Bundesamt fuer Strahlenschutz, Oberschleissheim (Germany)

2012-06-15

The radiation exposure after a short-term release of radioactive substances is often calculated assuming equilibrium conditions. An example is that of the German Incident Calculation Bases for nuclear power plants with pressurized water reactors. Here, the contamination of human milk is calculated using transfer factors. Applying this equilibrium model to incident situations raises the question whether baby's radiation exposure is adequately assessed. This contribution shows that compliance with the relevant dose limits of paragraph 49 of the German Radiation Protection Ordinance is ensured for design basis accidents on the assumption that the hypothetical breastfeeding period starts at the beginning of the activity release. Comparative analyses were performed against the biokinetic models applied by ICRP for radiation protection purposes, taking the reference nuclides {sup 137}Cs, {sup 90}Sr, {sup 131}I, {sup 241}Am and long-lived plutonium isotopes as examples. (orig.)

{sup 131}I-SPGP internal dosimetry: animal model and human extrapolation

Energy Technology Data Exchange (ETDEWEB)

Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soprani, Juliana; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: hma@cdtn.br; Figueiredo, Suely Gomes de [Universidade Federal do Espirito Santo, (UFES), Vitoria, ES (Brazil). Dept. de Ciencias Fisiologicas. Lab. de Quimica de Proteinas

2009-07-01

Scorpaena plumieri is commonly called moreia-ati or manganga and is the most venomous and one of the most abundant fish species of the Brazilian coast. Soprani 2006, demonstrated that SPGP - an isolated protein from S. plumieri fish- possess high antitumoral activity against malignant tumours and can be a source of template molecules for the development (design) of antitumoral drugs. In the present work, Soprani's {sup 125}ISPGP biokinetic data were treated by MIRD formalism to perform Internal Dosimetry studies. Absorbed doses due to the {sup 131}I-SPGP uptake were determinate in several organs of mice, as well as in the implanted tumor. Doses obtained for animal model were extrapolated to humans assuming a similar ratio for various mouse and human tissues. For the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from {sup 131}I were considered. (author)

Blood doses and remnant biokinetics after thyroid ablation therapy of differentiated thyroid cancer: withdrawal vs. rh TSH

International Nuclear Information System (INIS)

Lassmann, Michael; Haenscheid, Heribert; Luster, Markus; Reiners, Christoph; Ablation, Trial Study Group

2005-01-01

Full text: An international randomized multicenter trial (9 sites; North America: 5, Europe: 4) was carried out investigating the effectiveness of ablation therapy with 3.7 GBq 131 I in differentiated thyroid cancer. We present the results of the trial dosimetry assessments. 63 patients were randomized after thyroidectomy to either hypothyroidism (THW) or euthyroidism in combination with rh TSH (0.9 mg q d x 2, Thyrogen). The biokinetics and residence times (RT) of the remnants were assessed from 3 neck scans starting 48 h after administration. The blood doses (a surrogate for the bone marrow dose) were calculated from activity concentrations in blood samples and 131 I whole body retention measurements between 2 and 168 h after 131 I administration. The overall dosimetry results were calculated centrally (Wuerzberg) in an externally audited standardized data evaluation procedure. The patient ablation rate was 100%. The 48 h 131 I uptake was lower in the remnant tissue of the rh TSH group: 0.5 ± 0.7%; THW group: 0.9 ±1.0% (p=0.1), the effective half life showed smaller values for the THW group (48.0 ± 52.6 h vs. 67.6 ± 48.9 h, p=0.0116). The mean RT in the remnant tissue was shorter in the rh TSH group: 0.9 ± 1.3 h; THW group: 1.4 ± 1.5 h (p=0.1). A greater decrease in the mean percentage of administered activity in the blood at 48 h, and a lower mean residence time was seen in the rh TSH group: 0.8%, RT: 2.3 ± 0.7 h; THW group: 1.8% (p=0.0011), RT: 3.5 ± 1.63 h (p=0.0004). The mean specific blood dose was significantly lower (p<0.0001) in the rh TSH group (0.072 ± 0.017 mGy/MBq, blood vessel radius (VR):0.2 mm; 0.104 ± 0.025 mGy/MBq, VR: 5 mm) than in the Hypothyroid group (0.106 ± 0.037 mGy/MBq, VR: 0.2 mm; 0.158 ± 0.059 mGy/MBq, VR: 5 mm). Conclusion: Although the remnant RT tended to be lower in the rh TSH group the ablation rates in the 2 study arms were comparable. The radiation dose to the blood was significantly lower in the rh TSH group. This

Biological behaviour of plutonium inhaled by baboons as plutonium n-tributylphosphate complex. Comparison with ICRP models

International Nuclear Information System (INIS)

Metivier, H.; Duserre, C.; Rateau, G.; Legendre, N.; Masse, R.; Piechowski, J.; Menoux, B.

1989-01-01

In order to devise a model capable of calculating committed doses for workers contaminated by inhalation of plutonium tributylphosphate complex during reprocessing, we investigated the biokinetics of plutonium in baboons after inhalation of this chemical form. The animals were killed 0.6, 3, 15, 30, 90 and 365 days post inhalation. Urine and faeces were collected daily. After killing, the main organs were collected for chemical analysis. In order to improve our knowledge of the behaviour of systemic plutonium, three baboons were given an intravenous injection of Pu-TBP and were respectively killed 2, 30 and 365 days post injection. We observed that Pu-TBP could be classified as a W compound, with a half-time for lung clearance of 150 days. Urinary Pu excretion was 3 times higher than was expected from Durbin's model, suggesting that Pu introduced as Pu-TBP, is extremely mobile, and that the complex formed with blood proteins differs from the one formed after inhalation of plutonium nitrate. (author)

The effect of isotope on the dosimetry of inhaled plutonium oxide

International Nuclear Information System (INIS)

Guilmette, R.A.; Griffith, W.C.

1991-01-01

Results of experimental studies in which animals inhaled 238 PuO 2 or 239 PuO 2 aerosols have shown that the biokinetics and associated radiation dose patterns for these two isotopes differ significantly due to differences in in-vivo solubility caused by the 260-fold difference in specific activity between 238 PuO 2 and 239 PuO 2 . We have adapted a biokinetics and dosimetry model derived from results of the ITRI dog studies to humans and have calculated dose commitments and annual limits on intake (ALI) for both Pu isotopes. Our results show that the ALI calculated in this study is one-third that for class Y 238 Pu from ICRP 30, and one-half or equal to that for class Y 239 Pu, depending on how activity in the thoracic lymph nodes is treated dosimetrically

A comprehensive approach to age-dependent dosimetric modeling

International Nuclear Information System (INIS)

Leggett, R.W.; Cristy, M.; Eckerman, K.F.

1986-01-01

In the absence of age-specific biokinetic models, current retention models of the International Commission on Radiological Protection (ICRP) frequently are used as a point of departure for evaluation of exposures to the general population. These models were designed and intended for estimation of long-term integrated doses to the adult worker. Their format and empirical basis preclude incorporation of much valuable physiological information and physiologically reasonable assumptions that could be used in characterizing the age-specific behavior of radioelements in humans. In this paper we discuss a comprehensive approach to age-dependent dosimetric modeling in which consideration is given not only to changes with age in masses and relative geometries of body organs and tissues but also to best available physiological and radiobiological information relating to the age-specific biobehavior of radionuclides. This approach is useful in obtaining more accurate estimates of long-term dose commitments as a function of age at intake, but it may be particularly valuable in establishing more accurate estimates of dose rate as a function of age. Age-specific dose rates are needed for a proper analysis of the potential effects on estimates or risk of elevated dose rates per unit intake in certain stages of life, elevated response per unit dose received during some stages of life, and age-specific non-radiogenic competing risks

A comprehensive approach to age-dependent dosimetric modeling

International Nuclear Information System (INIS)

Leggett, R.W.; Cristy, M.; Eckerman, K.F.

1987-01-01

In the absence of age-specific biokinetic models, current retention models of the International Commission of Radiological Protection (ICRP) frequently are used as a point of departure for evaluation of exposures to the general population. These models were designed and intended for estimation of long-term integrated doses to the adult worker. Their format and empirical basis preclude incorporation of much valuable physiological information and physiologically reasonable assumptions that could be used in characterizing the age-specific behavior of radioelements in humans. In this paper a comprehensive approach to age-dependent dosimetric modeling is discussed in which consideration is given not only to changes with age in masses and relative geometries of body organs and tissues but also to best available physiological and radiobiological information relating to the age-specific biobehavior of radionuclides. This approach is useful in obtaining more accurate estimates of long-term dose commitments as a function of age at intake, but it may be particularly valuable in establishing more accurate estimates of dose rate as a function of age. Age-specific dose rates are needed for a proper analysis of the potential effects on estimates of risk of elevated dose rates per unit intake in certain stages of life, elevated response per unit dose received during some stages of life, and age-specific non-radiogenic competing risks. 16 refs.; 3 figs.; 1 table

131I-CRTX internal dosimetry: animal model and human extrapolation

International Nuclear Information System (INIS)

Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soares, Marcella Araugio; Silveira, Marina Bicalho; Santos, Raquel Gouvea dos

2009-01-01

Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumor cells but also in the processes of tumor cell adhesion, migration and angiogenesis. 125 I-Crtx, a radiolabeled version of a peptide derived from Crotalus durissus terrificus snake venom, specifically binds to tumor and triggers apoptotic signalling. At the present work, 125 I-Crtx biokinetic data (evaluated in mice bearing Erlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for 131 I-Crtx. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from 131 I in the tissue were considered in dose calculations. (author)

Implications of human tissue studies

International Nuclear Information System (INIS)

Kathren, R.L.

1986-10-01

Through radiochemical analysis of voluntary tissue donations, the United States Transuranium and Uranium Registries are gaining improved understanding of the distribution and biokinetics of actinide elements in occupationally exposed persons. Evaluation of the first two whole body contributions to the Transuranium Registry revealed an inverse proportionality between actinide concentration and bone ash fraction. The analysis of a whole body with a documented 241 Am deposition indicated a significantly shorter half-time in liver and a greater fraction resident in the skeleton than predicted by existing models. Other studies of the Registries are designed to evaluate in vivo estimates of actinide deposition with those derived from postmortem tissue analysis, compare results of animal experiments with human data, and reviw histopathologic slides for tissue toxicity that might be attributable to exposure to uranium and the transuranic elements. The implications of these recent findings and other work of the Registries are discussed from the standpoint of their potential impact on biokinetic modeling, internal dose assessment, safety standards, and operational health physics practices

{sup 131}I-CRTX internal dosimetry: animal model and human extrapolation

Energy Technology Data Exchange (ETDEWEB)

Andrade, Henrique Martins de; Ferreira, Andrea Vidal; Soares, Marcella Araugio; Silveira, Marina Bicalho; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN-CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: hma@cdtn.br

2009-07-01

Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumor cells but also in the processes of tumor cell adhesion, migration and angiogenesis. {sup 125}I-Crtx, a radiolabeled version of a peptide derived from Crotalus durissus terrificus snake venom, specifically binds to tumor and triggers apoptotic signalling. At the present work, {sup 125}I-Crtx biokinetic data (evaluated in mice bearing Erlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for {sup 131}I-Crtx. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from {sup 131}I in the tissue were considered in dose calculations. (author)

A model for the transfer of alkaline earth elements to the fetus

International Nuclear Information System (INIS)

Fell, T.P.; Harrison, J.D.; Leggett, R.W.

2001-01-01

A biokinetic model has been developed for the transfer of calcium, strontium, barium and radium to the human fetus. For the mother, ICRP models were adapted for pregnancy to include increases in gastrointestinal absorption, urinary excretion and bone turnover rates. The fetus was modelled with blood, soft tissue and bone compartments. Fetal requirements for Ca were determined by skeletal calcification, and recycling between fetal and maternal blood was included. Daily transfer of Sr, Ba and Ra to the fetus was taken to be lower than for Ca by factors of 0.6 for Sr and 0.4 for Ba and Ra. For acute intakes in late pregnancy at 35 weeks after conception, when maximum transfer occurs, the model predicts whole-body fetus:mother concentration ratios (C F :C M ) of 18 for Ca, 8 for Sr and 2 for Ba and Ra, respectively. Estimates of committed equivalent doses to the red bone marrow of offspring, including in utero and postnatal dose, after maternal ingestion in late pregnancy, were greater than corresponding doses in adults by factors of 20-30 for 45 Ca, 2-3 for 90 Sr and 3-4 for 226 Ra but slightly lower (0.8-0.9) for 133 Ba. (author)

Energy Metabolism and Human Dosimetry of Tritium

International Nuclear Information System (INIS)

Galeriu, D.; Takeda, H.; Melintescu, A.; Trivedi, A.

2005-01-01

In the frame of current revision of human dosimetry of 14 C and tritium, undertaken by the International Commission of Radiological Protection, we propose a novel approach based on energy metabolism and a simple biokinetic model for the dynamics of dietary intake (organic 14 C, tritiated water and Organically Bound Tritium-OBT). The model predicts increased doses for HTO and OBT comparing to ICRP recommendations, supporting recent findings

The work of Committee 2 of ICRP in developing dose coefficients for the embryo and fetus following intakes of radionuclides by the mother

International Nuclear Information System (INIS)

Stather, J.W.; Phipps, A.W.

1999-01-01

Committee 2 of the International Commission on Radiological Protection has the responsibility for calculating radiation doses from intakes of radionuclides for all age groups in the population. This includes the development of models for calculating doses to the embryo and fetus following intakes of radionuclides by the mother. The development of both biokinetic and dosimetric models are reviewed and the results of preliminary dose calculations presented. (orig.) [de

Biokinetics and dosimetry in patients of 99mTc-HYNIC-Lys3-Bombesin: images of GRP receptors

International Nuclear Information System (INIS)

Santos C, C. L.

2007-01-01

The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [ 99m Tc]EDDA/HYNIC-Lys 3 -bombesin ( 99m Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using 99m Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after 99m Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate 99m Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. 99m Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red marrow). The mean effective dose

Use of positron emission tomography for determination of tissue specific kinetics

International Nuclear Information System (INIS)

Miller, L.F.; Kabalka, G.; Khan, M.; Rahim, A.; Wyatt, M.; Thie, J.; Apostoaei, I.; Nichols, T.; Smith, G.

2000-01-01

Dynamic PET scans from several patients with GBM are analyzed to determine the biokinetic characteristics of various tissue types. Time-dependent responses are extracted from several regions of interest (ROIs), and these time-dependent data sets are analyzed to obtain biokinetic information from normal brain tissue, from various regions of tumors, and from areas that represent concentration in blood. Uptake rates, time constants, and other biokinetic data are obtained. It is noted that rates of uptake in tumor regions are approximately twice as fast as in normal tissue and that two rates of uptake are clearly identified in each tissue region and in blood. This information is useful for optimization of BNCT treatment protocols and for determining rate constants that can be related to cellular-level distributions of pharmaceuticals. (author)

Activated sludge model (ASM) based modelling of membrane bioreactor (MBR) processes: a critical review with special regard to MBR specificities.

Science.gov (United States)

Fenu, A; Guglielmi, G; Jimenez, J; Spèrandio, M; Saroj, D; Lesjean, B; Brepols, C; Thoeye, C; Nopens, I

2010-08-01

Membrane bioreactors (MBRs) have been increasingly employed for municipal and industrial wastewater treatment in the last decade. The efforts for modelling of such wastewater treatment systems have always targeted either the biological processes (treatment quality target) as well as the various aspects of engineering (cost effective design and operation). The development of Activated Sludge Models (ASM) was an important evolution in the modelling of Conventional Activated Sludge (CAS) processes and their use is now very well established. However, although they were initially developed to describe CAS processes, they have simply been transferred and applied to MBR processes. Recent studies on MBR biological processes have reported several crucial specificities: medium to very high sludge retention times, high mixed liquor concentration, accumulation of soluble microbial products (SMP) rejected by the membrane filtration step, and high aeration rates for scouring purposes. These aspects raise the question as to what extent the ASM framework is applicable to MBR processes. Several studies highlighting some of the aforementioned issues are scattered through the literature. Hence, through a concise and structured overview of the past developments and current state-of-the-art in biological modelling of MBR, this review explores ASM-based modelling applied to MBR processes. The work aims to synthesize previous studies and differentiates between unmodified and modified applications of ASM to MBR. Particular emphasis is placed on influent fractionation, biokinetics, and soluble microbial products (SMPs)/exo-polymeric substances (EPS) modelling, and suggestions are put forward as to good modelling practice with regard to MBR modelling both for end-users and academia. A last section highlights shortcomings and future needs for improved biological modelling of MBR processes. (c) 2010 Elsevier Ltd. All rights reserved.

Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

Energy Technology Data Exchange (ETDEWEB)

Leggett, R.W.

2003-09-10

Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.

Biokinetics of 131I in human organism

International Nuclear Information System (INIS)

Hermanska, J.; Nemec, J.; Karny, M.; Guy, T.V.; Jirsa, L.; Blazek, T.

1995-01-01

Time evolution of the cumulated activity in human body is one of the key characteristics determining medical impacts of ionizing radiation. In nuclear medicine, so called effective half-life is mostly used for the evolution description. This quantity is usually estimated by fitting a straight line in semi-logarithmic coordinates. Its novel Bayesian estimate was also proposed and its advantageous properties were verified. During extensive tests, it was found that the effective half-live has limited use as the underlying deterministic relationship time - activity can hardly be taken as (mono)exponential. It stimulated the research for a better and still simple model. A quadratic dependence of ln(activity) on ln(time) was found as an adequate candidate. Preliminary experiments on a restricted set of real data were promising enough to justify its further elaboration. (authors) 1 tab., 19 refs

Effect of Dietary Intake of Stable Iodine on Dose-per-unit-intake Factors for 99Tc

International Nuclear Information System (INIS)

Strom, Daniel J.

2003-01-01

It is well-known that the human thyroid concentrates iodine more than 100 times the concentration in plasma. Also well-known is the fact that large amounts of stable iodine in the diet can limit thyroid uptake of total iodine; this is the basis for administering potassium iodide following a release of radioiodine from a nuclear reactor accident or nuclear weapon detonation. Many researchers have shown enhanced concentrations of both organic and inorganic iodine in saliva and breast milk. Technetium-99 is a long-lived (231,000 year half-life) radionuclide of concern in the management of high-level radioactive waste. There is no doubt that 99Tc, if it is in groundwater, will be found in the chemical form of pertechnetate, 99TcO4?. Pertechnetate is a large anion, almost identical in size to iodide, I?. The nuclear medicine literature shows that pertechnetate concentrates in the thyroid, salivary glands, and lactating breast in addition to the stomach, liver, and alimentary tract as currently recognized by the International Commission on Radiological Protection (ICRP). The fact that large intakes of stable iodine (127I) in the diet limit uptake of iodine by the thyroid leads one to generalize that stable iodine in the diet may also limit thyroid uptake of pertechnetate. While there is at least one report that iodine in the diet blocks uptake of 99mTcO4? by the thyroid and salivary glands (which have the same Na/I symporter, the biochemical concentration mechanism), the level of protective effect seen for blocking radioactive iodine is not expected for 99TcO4? because pertechnetate does not become organically bound in the thyroid and thus is not retained for months the way iodide is. While it does account for Tc concentration in the thyroid, the existing ICRP biokinetic model for technetium does not take enhanced concentrations in salivary gland and breast tissue into account. From the survey of the nuclear medicine literature, it is not possible to compute the effect

Effect of Dietary Intake of Stable Iodine on Dose-per-unit-intake Factors for 99Tc

Energy Technology Data Exchange (ETDEWEB)

Strom, Daniel J.

2003-09-30

It is well-known that the human thyroid concentrates iodine more than 100 times the concentration in plasma. Also well-known is the fact that large amounts of stable iodine in the diet can limit thyroid uptake of total iodine; this is the basis for administering potassium iodide following a release of radioiodine from a nuclear reactor accident or nuclear weapon detonation. Many researchers have shown enhanced concentrations of both organic and inorganic iodine in saliva and breast milk. Technetium-99 is a long-lived (231,000 year half-life) radionuclide of concern in the management of high-level radioactive waste. There is no doubt that 99Tc, if it is in groundwater, will be found in the chemical form of pertechnetate, 99TcO4?. Pertechnetate is a large anion, almost identical in size to iodide, I?. The nuclear medicine literature shows that pertechnetate concentrates in the thyroid, salivary glands, and lactating breast in addition to the stomach, liver, and alimentary tract as currently recognized by the International Commission on Radiological Protection (ICRP). The fact that large intakes of stable iodine (127I) in the diet limit uptake of iodine by the thyroid leads one to generalize that stable iodine in the diet may also limit thyroid uptake of pertechnetate. While there is at least one report that iodine in the diet blocks uptake of 99mTcO4? by the thyroid and salivary glands (which have the same Na/I symporter, the biochemical concentration mechanism), the level of protective effect seen for blocking radioactive iodine is not expected for 99TcO4? because pertechnetate does not become organically bound in the thyroid and thus is not retained for months the way iodide is. While it does account for Tc concentration in the thyroid, the existing ICRP biokinetic model for technetium does not take enhanced concentrations in salivary gland and breast tissue into account. From the survey of the nuclear medicine literature, it is not possible to compute the effect

The 10th international congress of IRPA. The development of models for internal dosimetry

International Nuclear Information System (INIS)

Stather, J.W.

2000-01-01

In the past ten years a series of Publications have been issued by Committee 2 of the International Commission on Radiological Protection (ICRP) giving dose coefficients for intakes of radionuclides by inhalation and ingestion for both members of the public and workers. The biokinetic and dosimetric models used in the calculation of dose coefficients have been based largely on the model structure adopted in ICRP Publication 30 although new, physiologically-based models, involving recycling of radionuclides have been developed for both the alkaline earth and actinide elements. In addition, a new model for the human respiratory tract (HRTM) has been developed. A comprehensive series of dose coefficients have also been published by ICRP on CD-ROM. The series of reports giving dose coefficients for members of the public of various ages is to be completed with the issue of two further reports. The first will give dose coefficients for the embryo, fetus and newborn child following intakes of radionuclides by the mother either before or during pregnancy. Models for infants and children can generally be based on those for adults, with modifications to parameter values, but in the case of the embryo and fetus, fundamentally new models have had to be developed. Models are also being developed for calculating radiation doses to the offspring as a result of the intake of radionuclides in breast milk. The HRTM used for calculating inhalation dose coefficients was developed to allow the use of material specific data. To date, however, it has only been applied using default model parameters. A technical report is being developed that will give guidance on the practical application of the HRTM in circumstances which require the use of data on the deposition and solubility characteristics of specific inhaled materials. The present model used for assessing doses from ingestion of radionuclides was prepared in 1966. An improved model for the human alimentary tract is being developed

Development of an Age- and Gender-specific Model for Strontium Metabolism in Humans

International Nuclear Information System (INIS)

Shagina, N. B.; Degteva, M. O.; Tolstykh, E. I.

2004-01-01

This paper presents a development of a new biokinetic model for strontium, which accounts for age and gender differences of metabolism in humans. This model was developed based on the long-term follow-up of the residents living on the banks of the Techa River (Southern Urals, Russia) contaminated with 89,90Sr in 1950-1956. The new model uses the structure of ICRP model for strontium but model parameters have been estimated to account for age, gender and population differences in strontium retention and elimination. Estimates of age- and gender-specific model parameters were derived from (a) the results of long-term measurements of 90Sr-body burden for the Techa River population; (b) experimental studies of calcium and strontium metabolism in humans and (c) non-radiological data regarding bone metabolism (mineral content of the body, bone turnover, etc). As a result, the new model satisfactorily describes data on long-term retention of 90Sr in residents of the Techa River settlements of all ages and both genders and also data from studies during the period of global fallout in the UK and the USA and experimental data on strontium retention in humans. The new model can be used to calculate dose from 89,90Sr for the Techa River residents and also for other populations with similar parameters of skeletal maturation and also for other populations with similar parameters of skeletal maturation and involution. (Author) 27 refs

Biokinetic model-based multi-objective optimization of Dunaliella tertiolecta cultivation using elitist non-dominated sorting genetic algorithm with inheritance.

Science.gov (United States)

Sinha, Snehal K; Kumar, Mithilesh; Guria, Chandan; Kumar, Anup; Banerjee, Chiranjib

2017-10-01

Algal model based multi-objective optimization using elitist non-dominated sorting genetic algorithm with inheritance was carried out for batch cultivation of Dunaliella tertiolecta using NPK-fertilizer. Optimization problems involving two- and three-objective functions were solved simultaneously. The objective functions are: maximization of algae-biomass and lipid productivity with minimization of cultivation time and cost. Time variant light intensity and temperature including NPK-fertilizer, NaCl and NaHCO 3 loadings are the important decision variables. Algal model involving Monod/Andrews adsorption kinetics and Droop model with internal nutrient cell quota was used for optimization studies. Sets of non-dominated (equally good) Pareto optimal solutions were obtained for the problems studied. It was observed that time variant optimal light intensity and temperature trajectories, including optimum NPK fertilizer, NaCl and NaHCO 3 concentration has significant influence to improve biomass and lipid productivity under minimum cultivation time and cost. Proposed optimization studies may be helpful to implement the control strategy in scale-up operation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Uncertainties in Organ Burdens Estimated from PAS

International Nuclear Information System (INIS)

La Bone, T.R.

2004-01-01

To calculate committed effective dose equivalent, one needs to know the quantity of the radionuclide in all significantly irradiated organs (the organ burden) as a function of time following the intake. There are two major sources of uncertainty in an organ burden estimated from personal air sampling (PAS) data: (1) The uncertainty in going from the exposure measured with the PAS to the quantity of aerosol inhaled by the individual, and (2) The uncertainty in going from the intake to the organ burdens at any given time, taking into consideration the biological variability of the biokinetic models from person to person (interperson variability) and in one person over time (intra-person variability). We have been using biokinetic modeling methods developed by researchers at the University of Florida to explore the impact of inter-person variability on the uncertainty of organ burdens estimated from PAS data. These initial studies suggest that the uncertainties are so large that PAS might be considered to be a qualitative (rather than quantitative) technique. These results indicate that more studies should be performed to properly classify the reliability and usefulness of using PAS monitoring data to estimate organ burdens, organ dose, and ultimately CEDE

Biokinetics and radiation dosimetry of 14C-labelled triolein, urea, glycocholic acid and xylose in man. Studies related to nuclear medicine 'breath tests' using accelerator mass spectrometry

International Nuclear Information System (INIS)

Gunnarsson, Mikael

2002-08-01

14 C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. In this work detailed long-term biokinetic and dosimetric estimation have been carried out for four clinically used 14 C-breath tests: 14 C-triolein (examination of fat malabsorption), urea (detection of Helicobacter pylori infection in the stomach), glycocholic acid and xylose (examination of bacterial overgrowth in the small intestine) by using the highly sensitive accelerator mass-spectrometry (AMS) technique. The AMS technique has been used to measure low 14 C concentrations in small samples of exhaled air, urine, faeces and tissue samples and has improved the base for the estimation of the absorbed dose to various organs and tissues and the effective dose to man. The high sensitivity of the AMS system has also made it possible to perform 14 C breath tests on patient groups which were earlier subject for restriction (e.g. small children). In summary, our results show that for adult patients - and in the case of 14 C-urea breath test also for children down to 3 years of age - the dose contributions are comparatively low, both described as organ doses and as effective doses. For adults, the latter is: 14 C-glycocholic acid - 0.4 mSv/MBq, 14 C-triolein - 0.3 mSv/MBq, 14 C-xylose - 0.1 mSv/MBq and 14 C-urea - 0.04 mSv/MBq. Thus, from a radiation protection point of view there is no reason for restrictions in using any of the 14 C-labelled radiopharmaceutical included in this work in the activities normally used (0.07-0.2 MBq for a 70 kg patient)

Targeted imaging of gastrin-releasing peptide receptors with 99mTc-EDDA/HYNIC-[Lys3]-bombesin: biokinetics and dosimetry in women.

Science.gov (United States)

Santos-Cuevas, Clara L; Ferro-Flores, Guillermina; Arteaga de Murphy, Consuelo; Pichardo-Romero, Pablo A

2008-08-01

The gastrin-releasing peptide receptor (GRP-R) is expressed in several normal human tissues and is overexpressed in various human tumors including breast, prostate, small-cell lung cancer and pancreatic cancer. Recently, 99mTc-EDDA/HYNIC-[Lys]-bombesin (99mTc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-R binding and rapid cell internalization. The aim of this study was to determine the biokinetics and dosimetry of 99mTc-HYNIC-BN and the feasibility of using this radiopharmaceutical to image GRP-R in four early breast cancer patients and seven healthy women. Whole-body images were acquired at 20, 90, 180 min, and 24 h after 99mTc-HYNIC-BN administration. The same regions of interest were drawn around source organs on each time frame and regions of interest were converted to activity (conjugate view counting method). The image sequence was used to extrapolate 99mTc-HYNIC-BN time-activity curves in each organ to calculate the total number of disintegrations (N) that occurred in the source regions. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. 99mTc-HYNIC-BN had a rapid blood clearance with mainly renal excretion. No statistically significant differences (P>0.05) in the radiation-absorbed doses among cancer patients and healthy women were observed. The average equivalent doses (n=11) were 24.8+/-8.8 mSv (kidneys), 7.3+/-1.8 mSv (lungs), 6.5+/-4.0 mSv (breast), 2.0+/-0.3 mSv (pancreas), 1.6+/-0.3 mSv (liver), 1.2+/-0.2 mSv (ovaries), and 1.0+/-0.2 mSv (red marrow). The effective dose was 3.3+/-0.6 mSv. The images showed well-differentiated concentration of 99mTc-HYNIC-BN in cancer mammary tissue. All the absorbed doses were comparable with those known for most of the 99mTc studies. 99mTc-HYNIC-BN shows high tumor uptake in breasts with malignant tumors so it is a promising imaging radiopharmaceutical to target site-specific early breast cancer. The results obtained

Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario

Energy Technology Data Exchange (ETDEWEB)

Vives i Batlle, J.; Beresford, N. A.; Beaugelin-Seiller, K.; Bezhenar, R.; Brown, J.; Cheng, J. -J.; Ćujić, M.; Dragović, S.; Duffa, C.; Fiévet, B.; Hosseini, A.; Jung, K. T.; Kamboj, S.; Keum, D. -K.; Kryshev, A.; LePoire, D.; Maderich, V.; Min, B. -I.; Periáñez, R.; Sazykina, T.; Suh, K. -S.; Yu, C.; Wang, C.; Heling, R.

2016-03-01

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of 90Sr, 131I and 137Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters.

Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Dose reconstruction. Final report

International Nuclear Information System (INIS)

Jacob, P.; Aragno, D.; Bailiff, I.K.

2000-01-01

The project Dose Reconstruction was conducted within the five work packages: - EPR with teeth, - Chromosome painting (FISH) in lymphocytes, - Luminescence methods, - Modelling, and - Evaluation. (orig.)

ICRP new recommendations. Committee 2's efforts

International Nuclear Information System (INIS)

Eckerman, K.F.

2007-01-01

The International Commission on Radiological Protection (ICRP) may release new primary radiation protection recommendation in 2007. Committee 2 has underway reviews of the dosimetric and biokinetic models and associated data used in calculating dose coefficients for intakes of radionuclides and exposures to external radiation fields. This paper outlines the work plans of Committee 2 during the current term, 2005-2009, in anticipation of the new primary recommendations. The two task groups of Committee 2 responsible for the computations of dose coefficients, INDOS and DOCAL, are reviewing the models and data used in the computations. INDOS is reviewing the lung model and the biokinetic models that describe the behavior of the radionuclides in the body. DOCAL is reviewing its computational formulations with the objective of harmonizing the formulation with those of nuclear medicine, and developing new computational phantoms representing the adult male and female reference individuals of ICRP Publication 89. In addition, DOCAL will issue a publication on nuclear decay data to replace ICRP Publication 38. While the current efforts are focused on updating the dose coefficients for occupational intakes of radionuclides plans are being formulated to address dose coefficients for external radiation fields which include consideration of high energy fields associated with accelerators and space travel and the updating of dose coefficients for members of the public. (author)

Uncertainties in Cancer Risk Coefficients for Environmental Exposure to Radionuclides. An Uncertainty Analysis for Risk Coefficients Reported in Federal Guidance Report No. 13

Energy Technology Data Exchange (ETDEWEB)

Pawel, David [U.S. Environmental Protection Agency; Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL; Nelson, Christopher [U.S. Environmental Protection Agency

2007-01-01

Federal Guidance Report No. 13 (FGR 13) provides risk coefficients for estimation of the risk of cancer due to low-level exposure to each of more than 800 radionuclides. Uncertainties in risk coefficients were quantified in FGR 13 for 33 cases (exposure to each of 11 radionuclides by each of three exposure pathways) on the basis of sensitivity analyses in which various combinations of plausible biokinetic, dosimetric, and radiation risk models were used to generate alternative risk coefficients. The present report updates the uncertainty analysis in FGR 13 for the cases of inhalation and ingestion of radionuclides and expands the analysis to all radionuclides addressed in that report. The analysis indicates that most risk coefficients for inhalation or ingestion of radionuclides are determined within a factor of 5 or less by current information. That is, application of alternate plausible biokinetic and dosimetric models and radiation risk models (based on the linear, no-threshold hypothesis with an adjustment for the dose and dose rate effectiveness factor) is unlikely to change these coefficients by more than a factor of 5. In this analysis the assessed uncertainty in the radiation risk model was found to be the main determinant of the uncertainty category for most risk coefficients, but conclusions concerning the relative contributions of risk and dose models to the total uncertainty in a risk coefficient may depend strongly on the method of assessing uncertainties in the risk model.

Evaluation of the absorbed dose to the kidneys due to Tc99m (DTPA) / Tc99m (Mag3) and Tc99m (Dmsa)

International Nuclear Information System (INIS)

Vasquez A, M.; Murillo C, F.; Castillo D, C.; Rocha J, J.; Sifuentes D, Y.; Sanchez S, P.; Idrogo C, J.; Marquez P, F.

2015-10-01

The absorbed dose in the kidneys of adult patients has been assessed using the biokinetics of radiopharmaceuticals containing Tc 99m (DTPA) / Tc 99m (Mag3) or Tc 99m (Dmsa).The absorbed dose was calculated using the formalism MIRD and the Cristy-Eckerman representation for the kidneys. The absorbed dose to the kidneys due to Tc 99m (DTPA) / Tc 99m (Mag3), are given by 0.00466 mGy.MBq -1 / 0.00339 mGy.MBq -1 . Approximately 21.2% of the absorbed dose is due to the bladder (content) and the remaining tissue, included in biokinetics of Tc 99m (DTPA) / Tc 99m (Mag3). The absorbed dose to the kidneys due to Tc 99m (Dmsa) is 0.17881 mGy.MBq -1 . Here, 1.7% of the absorbed dose is due to the bladder, spleen, liver and the remaining tissue, included in biokinetics of Tc 99m (Dmsa). (Author)

External costs of atmospheric lead emissions from a waste-to-energy plant: a follow-up assessment of indirect neurotoxic impacts via topsoil ingestion

DEFF Research Database (Denmark)

Pizzol, Massimo; Møller, Flemming; Thomsen, Marianne

2013-01-01

The link between anthropogenic emissions and the monetary value of their impacts, so-called external cost, can be determined via the impact pathway approach. This method is used in the present study to calculate the indirect costs, via topsoil ingestion, of lead emitted into atmosphere from a waste......-to-energy facility in Denmark. The Operational Meteorological air-quality model, the Simplified Fate and Speciation Model, and the Age Dependent Biokinetic Model are used to determine the metals’ atmospheric transport, its deposition and accumulation in topsoil, and its bio-accumulation in the human body...

Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Biophysical models for the induction of cancer by radiation. Final report

International Nuclear Information System (INIS)

Paretzke, H.G.; Ballarini, F.; Brugmans, M.

2000-01-01

The overall project is organised into seven work packages. WP1 concentrates on the development of mechanistic, quantitative models for radiation oncogenesis using selected data sets from radiation epidemiology and from experimental animal studies. WP2 concentrates on the development of mechanistic, mathematical models for the induction of chromosome aberrations. WP3 develops mechanistic models for radiation mutagenesis, particularly using the HPRT-mutation as a paradigm. WP4 will develop mechanistic models for damage and repair of DNA, and compare these with experimentally derived data. WP5 concentrates on the improvement of our knowledge on the chemical reaction pathways of initial radiation chemical species in particular those that migrate to react with the DNA and on their simulation in track structure codes. WP6 models by track structure simulation codes the production of initial physical and chemical species, within DNA, water and other components of mammalian cells, in the tracks of charged particles following the physical processes of energy transfer, migration, absorption, and decay of excited states. WP7 concentrates on the determination of the start spectra of those tracks considered in WP6 for different impinging radiation fields and different irradiated biological objects. (orig.)

Development of a computational code for the internal doses assessment of the main radionuclides of occupational exposure at IPEN

International Nuclear Information System (INIS)

Claro, Thiago Ribeiro

2011-01-01

The dose resulting from internal contamination can be estimated with the use of biokinetic models combined with experimental results obtained from bioanalysis and assessment of the time of incorporation. The biokinetics models are represented by a set of compartments expressing the transportation, retention and elimination of radionuclides from the body. The ICRP publications, number 66, 78 and 100, present compartmental models for the respiratory tract, gastrointestinal tract and for systemic distribution for an array of radionuclides of interest for the radiological protection. The objective of this work is to develop a computational code for the internal doses assessment of the main radionuclides of occupational exposure at IPEN. Consequently serving as a agile and efficient tool for the designing, visualization and resolution of compartmental models of any nature. The architecture of the system was conceived containing two independent software: CBT - responsible for the setup and manipulation of models and SSID - responsible for the mathematical solution of the models. Four different techniques are offered for the resolution of system of equations, including semi-analytical and numerical methods, allowing for comparison of precision and performance of both. The software was developed in C≠ programming, using a Microsoft Access database and XML standards for file exchange with other applications. Compartmental models for uranium, thorium and iodine radionuclides were generated for the validation of the CBT software. The models were subsequently solved via SSID software and the results compared with the values published in the issue 78 of ICRP. In all cases the system replicated the values published by ICRP. (author)

Development of a computational code for the internal doses assessment of the main radionuclides of occupational exposure at IPEN; Desenvolvimento de um codigo computacional de apoio ao calculo de dose interna para radionuclideos de interesse do IPEN

Energy Technology Data Exchange (ETDEWEB)

Claro, Thiago Ribeiro

2011-07-01

The dose resulting from internal contamination can be estimated with the use of biokinetic models combined with experimental results obtained from bioanalysis and assessment of the time of incorporation. The biokinetics models are represented by a set of compartments expressing the transportation, retention and elimination of radionuclides from the body. The ICRP publications, number 66, 78 and 100, present compartmental models for the respiratory tract, gastrointestinal tract and for systemic distribution for an array of radionuclides of interest for the radiological protection. The objective of this work is to develop a computational code for the internal doses assessment of the main radionuclides of occupational exposure at IPEN. Consequently serving as a agile and efficient tool for the designing, visualization and resolution of compartmental models of any nature. The architecture of the system was conceived containing two independent software: CBT - responsible for the setup and manipulation of models and SSID - responsible for the mathematical solution of the models. Four different techniques are offered for the resolution of system of equations, including semi-analytical and numerical methods, allowing for comparison of precision and performance of both. The software was developed in C{ne} programming, using a Microsoft Access database and XML standards for file exchange with other applications. Compartmental models for uranium, thorium and iodine radionuclides were generated for the validation of the CBT software. The models were subsequently solved via SSID software and the results compared with the values published in the issue 78 of ICRP. In all cases the system replicated the values published by ICRP. (author)

Compartmental analysis and dosimetric aspects applied to cholesterol with {sup 3}H labeled; Analise compartimental e aspectos dosimetricos aplicados ao colesterol marcado com {sup 3}H

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Adriano dos Santos

2015-07-01

Cardiovascular diseases (CVDs) are one of the major reasons of death around the world according to the World Health Organization (WHO). It is well known that changes in levels of plasma lipoproteins, which are responsible for the transport of cholesterol into the bloodstream, are associated with cardiovascular diseases. For this reason to know the biokinetic parameters of plasma lipoproteins and quantifies them is important to correct and deep understanding about the diseases associated with these disorders. The main aim of this study is to provide a biokinetic model and estimate the radiometric doses for {sup 3}H-Cholesterol, a radioactive tracer widely used in physiological and metabolic studies. The model was based on [Schwartz et al. 2004] about the distribution of cholesterol by the lipoprotein and gastrointestinal model [ICRP 30, 1979]. The doses distribution in compartments of the model and other organs and tissues of a standard adult described in [ICRP 106, 2008] was calculated using MIRD method (Medical Internal Radiation Dose) and compartmental analysis using the computer program Matlab®. The dose coefficients were estimated for a standard phantom man (73 kg) described in [ICRP 60, 1991]. The estimated doses for both model and for other organs were low and did not exceed the highest dose obtained that was in the upper large intestine, as 44,8 μGy these parameters will assist in ethics committee's opinions on the use of works that use the {sup 3}H-cholesterol which radioactive tracer. (author)

Compartmental analysis and dosimetric aspects applied to cholesterol with 3H labeled

International Nuclear Information System (INIS)

Oliveira, Adriano dos Santos

2015-01-01

Cardiovascular diseases (CVDs) are one of the major reasons of death around the world according to the World Health Organization (WHO). It is well known that changes in levels of plasma lipoproteins, which are responsible for the transport of cholesterol into the bloodstream, are associated with cardiovascular diseases. For this reason to know the biokinetic parameters of plasma lipoproteins and quantifies them is important to correct and deep understanding about the diseases associated with these disorders. The main aim of this study is to provide a biokinetic model and estimate the radiometric doses for 3 H-Cholesterol, a radioactive tracer widely used in physiological and metabolic studies. The model was based on [Schwartz et al. 2004] about the distribution of cholesterol by the lipoprotein and gastrointestinal model [ICRP 30, 1979]. The doses distribution in compartments of the model and other organs and tissues of a standard adult described in [ICRP 106, 2008] was calculated using MIRD method (Medical Internal Radiation Dose) and compartmental analysis using the computer program Matlab®. The dose coefficients were estimated for a standard phantom man (73 kg) described in [ICRP 60, 1991]. The estimated doses for both model and for other organs were low and did not exceed the highest dose obtained that was in the upper large intestine, as 44,8 μGy these parameters will assist in ethics committee's opinions on the use of works that use the 3 H-cholesterol which radioactive tracer. (author)

Worldwide bioassay data resources for plutonium/americium internal dosimetry studies

International Nuclear Information System (INIS)

Miller, G.; Bertelli, L.; Little, T.; Guilmette, R.; Riddell, T.; Filipy, R.

2005-01-01

Full text: Biokinetic models are the scientific underpinning of internal dosimetry. These models describe how materials of interest taken into the body by various routes (for example inhalation) are transported through the body, allowing the modelling of bioassay measurements and the estimation of radiation dose. The International Commission on Radiation Protection (ICRP) publishes biokinetic models for use in internal dosimetry. These models represent the consensus judgement of a committee of experts, based on human and animal data. Nonetheless, it is important to validate biokinetic models using directly applicable data, in a scientifically transparent manner, especially for internal dosimetry research purposes (as opposed to radiation protection), as in epidemiology studies. Two major goals would be to determine individual variations of model parameters for the purpose of assessing this source of uncertainty in internal dose calculations, and to determine values of workplace specific parameters (such as particle solubility in lung fluids) for different representative workplaces. Furthermore, data on the observed frequency of intakes under various conditions can be used in the interpretation of bioassay data. All of the above may be couched in the terminology of Bayesian statistical analysis and amount to the determination of the Bayesian prior probability distributions needed in a Bayesian interpretation of bioassay data. The authors have direct knowledge of several significant databases of plutonium/americium bioassay data (including autopsy data). The purpose of this paper is to acquaint the worldwide community with these resources and to invite others who may know of other such databases to participate with us in a publication that would document the content, form, and the procedures for seeking access to these databases. These databases represent a tremendous scientific resource in this field. Examples of databases known to the authors include: the

Biokinetics of {sup 131}I in human organism

Energy Technology Data Exchange (ETDEWEB)

Hermanska, J; Nemec, J [Faculty Hospital Motol, Prague (Czech Republic). Clinic of Nuclear Madecine; Karny, M; Guy, T V [Academy of Sciences of the Czech Republic, Prague (Czech Republic). Ist. of Information Theory and Automation; Jirsa, L; Blazek, T [Charles Univ., Prague (Czech Republic). 2nd Medical Faculty

1996-12-31

Time evolution of the cumulated activity in human body is one of the key characteristics determining medical impacts of ionizing radiation. In nuclear medicine, so called effective half-life is mostly used for the evolution description. This quantity is usually estimated by fitting a straight line in semi-logarithmic coordinates. Its novel Bayesian estimate was also proposed and its advantageous properties were verified. During extensive tests, it was found that the effective half-live has limited use as the underlying deterministic relationship time - activity can hardly be taken as (mono)exponential. It stimulated the research for a better and still simple model. A quadratic dependence of ln(activity) on ln(time) was found as an adequate candidate. Preliminary experiments on a restricted set of real data were promising enough to justify its further elaboration. (authors) 1 tab., 19 refs.

Plutonium biokinetics in humans

International Nuclear Information System (INIS)

Popplewell, D.; Ham, G.; McCarthy, W.; Lands, C.

1994-01-01

By using an 'unusual' isotope it is possible to carry out experiments with plutonium in volunteers at minimal radiation dose levels. Measurements have been made of the gut transfer factor and the urinary excretion of plutonium after intravenous injection. (author)

Bioaccumulation and trophic transfer of dioxins in marine copepods and fish

International Nuclear Information System (INIS)

Zhang Qiong; Yang Liuyan; Wang Wenxiong

2011-01-01

Despite the great concerns about dioxins in the marine environments, the biokinetics and bioaccumulation of these compounds in marine organisms remains little known. Using radioactive tracers the aqueous uptake, dietary assimilation efficiency, and elimination of dioxins were measured in marine phytoplankton, copepods and seabream. The calculated uptake rate constant of dioxins decreased with increasing trophic levels, whereas the dietary assimilation efficiency (AE) was 28.5-57.6% in the copepods and 36.6-70.2% in the fish. The dietary AE was highly dependent on the food concentrations and food type. The elimination rate constant of dioxin in the copepods varied with different exposure pathways as well as food concentration and food type. Biokinetic calculation showed that dietary accumulation was the predominant pathway for dioxin accumulation in marine copepods and fish. Aqueous uptake can be an important pathway only when the bioconcentration of dioxins in the phytoplankton was low. - Highlights: → Radiotracer was used to quantify the biokinetics of dioxins in a marine food chain. → Aqueous uptake rate of dioxins decreased with increasing trophic levels. → Dietary assimilation efficiencies were comparable between the copepods and the fish. → Both food type and density significantly affected the dietary assimilation of dioxins. → Diet was the predominant pathway for dioxin accumulation in marine copepods and fish. - Biokinetic calculation showed that dietary accumulation was the predominant pathway for dioxin accumulation in marine copepods and fish.

Thermodynamics proposes, kinetics decides, speciation dares: speciation of actinides in biological media

International Nuclear Information System (INIS)

Ansoborlo, E.

2005-06-01

After having recalled the content and purpose of his research thesis, the author proposes a detailed overview of the research works he performed thereafter in the field of the speciation of actinides at the level of the organism entry gates and in target tissues. These works therefore concern four important areas of research in radioprotection: bio-kinetic, toxicology, decorporation, and dosimetry studies. The author outlines how speciation studies can be useful for these different areas, and to better understand and describe, and therefore foresee, the biokinetics and toxicity of radionuclides

Biodistribution dosimetric study of radiopharmaceutical 99mTc Ixolaris in mice for melanoma diagnosis by molecular image and translational model for human beings

International Nuclear Information System (INIS)

Soriano, Sarah Canuto Silva

2015-01-01

The labeling of Ixolaris with 99m Tc was developed by Barboza et.al. (2013) aiming its use primarily in glioblastoma and after in melanoma diagnosis, a less common but very aggressive cancer and with high mortality rate. Preliminary tests on animals have proven its effectiveness of labeling but a dosimetric study to human clinical trials should be performed. This study aimed to: (1) determine the biokinetic model for the radiotracer 99m Tc-Ixolaris in mice by imaging dosimetry method; and (2) estimate the absorbed and effective dose resulting from the use of a new radiopharmaceutical for melanoma and metastases diagnosis in human beings, since a dosimetric study of new radiopharmaceuticals in animals is necessary to test them subsequently in humans and apply for registration in ANVISA. According to SPECT images, was found a latency period of 15 to 21 days for the development of lung metastasis in mice. Three C57BL6 mice, one control animal, and two animals with induced cell line B16-F10 murine melanoma were tested. The 99m Tc-Ixolaris radiopharmaceutical was administered intravenously in a caudal vein, and SPECT images were acquired 0.5 h, 1.5 h, 2.5 h, 3.5 h and 24 h post-administration for analysis and biodistribution quantification. The biokinetic model was determined and thus, obtained cumulative activity in order to estimate the absorbed dose in each organ. The mass and metabolic differences between mice and humans were considered and used to extrapolate the data acquired at different scales. Based on dose factors provided by the software MIRDOSE and Olinda (S factor), absorbed doses in irradiated target organs were calculated for the source organs, and finally the effective dose was estimated. The results indicate that for diagnostic exams conducted in human melanoma patients by administering approximately 25.7 MBq the estimated effective dose was 4.3 mSv. Comparing with effective doses obtained in other diagnostic techniques with 99m Tc, a range of effective

Grouping nanomaterials to predict their potential to induce pulmonary inflammation

Energy Technology Data Exchange (ETDEWEB)

Braakhuis, Hedwig M., E-mail: hedwig.braakhuis@rivm.nl [National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven (Netherlands); Department of Toxicogenomics, Maastricht University, PO Box 616, 6200 MD Maastricht (Netherlands); Oomen, Agnes G. [National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven (Netherlands); Cassee, Flemming R. [National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven (Netherlands); Institute of Risk Assessment Sciences, Utrecht University, PO Box 80.163, 3508 TD Utrecht (Netherlands)

2016-05-15

The rapidly expanding manufacturing, production and use of nanomaterials have raised concerns for both worker and consumer safety. Various studies have been published in which induction of pulmonary inflammation after inhalation exposure to nanomaterials has been described. Nanomaterials can vary in aspects such as size, shape, charge, crystallinity, chemical composition, and dissolution rate. Currently, efforts are made to increase the knowledge on the characteristics of nanomaterials that can be used to categorise them into hazard groups according to these characteristics. Grouping helps to gather information on nanomaterials in an efficient way with the aim to aid risk assessment. Here, we discuss different ways of grouping nanomaterials for their risk assessment after inhalation. Since the relation between single intrinsic particle characteristics and the severity of pulmonary inflammation is unknown, grouping of nanomaterials by their intrinsic characteristics alone is not sufficient to predict their risk after inhalation. The biokinetics of nanomaterials should be taken into account as that affects the dose present at a target site over time. The parameters determining the kinetic behaviour are not the same as the hazard-determining parameters. Furthermore, characteristics of nanomaterials change in the life-cycle, resulting in human exposure to different forms and doses of these nanomaterials. As information on the biokinetics and in situ characteristics of nanomaterials is essential but often lacking, efforts should be made to include these in testing strategies. Grouping nanomaterials will probably be of the most value to risk assessors when information on intrinsic characteristics, life-cycle, biokinetics and effects are all combined. - Highlights: • Grouping of nanomaterials helps to gather information in an efficient way with the aim to aid risk assessment. • Different ways of grouping nanomaterials for their risk assessment after inhalation are

Grouping nanomaterials to predict their potential to induce pulmonary inflammation

International Nuclear Information System (INIS)

Braakhuis, Hedwig M.; Oomen, Agnes G.; Cassee, Flemming R.

2016-01-01

The rapidly expanding manufacturing, production and use of nanomaterials have raised concerns for both worker and consumer safety. Various studies have been published in which induction of pulmonary inflammation after inhalation exposure to nanomaterials has been described. Nanomaterials can vary in aspects such as size, shape, charge, crystallinity, chemical composition, and dissolution rate. Currently, efforts are made to increase the knowledge on the characteristics of nanomaterials that can be used to categorise them into hazard groups according to these characteristics. Grouping helps to gather information on nanomaterials in an efficient way with the aim to aid risk assessment. Here, we discuss different ways of grouping nanomaterials for their risk assessment after inhalation. Since the relation between single intrinsic particle characteristics and the severity of pulmonary inflammation is unknown, grouping of nanomaterials by their intrinsic characteristics alone is not sufficient to predict their risk after inhalation. The biokinetics of nanomaterials should be taken into account as that affects the dose present at a target site over time. The parameters determining the kinetic behaviour are not the same as the hazard-determining parameters. Furthermore, characteristics of nanomaterials change in the life-cycle, resulting in human exposure to different forms and doses of these nanomaterials. As information on the biokinetics and in situ characteristics of nanomaterials is essential but often lacking, efforts should be made to include these in testing strategies. Grouping nanomaterials will probably be of the most value to risk assessors when information on intrinsic characteristics, life-cycle, biokinetics and effects are all combined. - Highlights: • Grouping of nanomaterials helps to gather information in an efficient way with the aim to aid risk assessment. • Different ways of grouping nanomaterials for their risk assessment after inhalation are

Biokinetics and radiation dosimetry of {sup 14}C-labelled triolein, urea, glycocholic acid and xylose in man. Studies related to nuclear medicine 'breath tests' using accelerator mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Gunnarsson, Mikael

2002-08-01

{sup 14}C-labelled substances have been used in biomedical research and clinical medicine for over 50 years. Physicians and scientists however, often hesitate to use these substances in patients and volunteers because the radiation dosimetry is unclear. In this work detailed long-term biokinetic and dosimetric estimation have been carried out for four clinically used {sup 14}C-breath tests: {sup 14}C-triolein (examination of fat malabsorption), urea (detection of Helicobacter pylori infection in the stomach), glycocholic acid and xylose (examination of bacterial overgrowth in the small intestine) by using the highly sensitive accelerator mass-spectrometry (AMS) technique. The AMS technique has been used to measure low {sup 14}C concentrations in small samples of exhaled air, urine, faeces and tissue samples and has improved the base for the estimation of the absorbed dose to various organs and tissues and the effective dose to man. The high sensitivity of the AMS system has also made it possible to perform {sup 14}C breath tests on patient groups which were earlier subject for restriction (e.g. small children). In summary, our results show that for adult patients - and in the case of {sup 14}C-urea breath test also for children down to 3 years of age - the dose contributions are comparatively low, both described as organ doses and as effective doses. For adults, the latter is: {sup 14}C-glycocholic acid - 0.4 mSv/MBq, {sup 14}C-triolein - 0.3 mSv/MBq, {sup 14}C-xylose - 0.1 mSv/MBq and {sup 14}C-urea - 0.04 mSv/MBq. Thus, from a radiation protection point of view there is no reason for restrictions in using any of the {sup 14}C-labelled radiopharmaceutical included in this work in the activities normally used (0.07-0.2 MBq for a 70 kg patient)

Evaluation of the absorbed dose to the kidneys due to Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3) and Tc{sup 99m} (Dmsa); Evaluacion de la dosis absorbida en los rinones debido al Tc{sup 99m} (DTPA) / Tc{sup 99m} (MAG3) y Tc{sup 99m} (DMSA)

Energy Technology Data Exchange (ETDEWEB)

Vasquez A, M.; Murillo C, F.; Castillo D, C.; Rocha J, J.; Sifuentes D, Y.; Sanchez S, P. [Universidad Nacional de Trujillo, Av. Juan Pablo II s/n, Trujillo (Peru); Idrogo C, J.; Marquez P, F., E-mail: marvva@hotmail.com [Instituto Nacional de Enfermedades Neoplasicas, Av. Angamos 2520, Lima (Peru)

2015-10-15

The absorbed dose in the kidneys of adult patients has been assessed using the biokinetics of radiopharmaceuticals containing Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3) or Tc{sup 99m} (Dmsa).The absorbed dose was calculated using the formalism MIRD and the Cristy-Eckerman representation for the kidneys. The absorbed dose to the kidneys due to Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3), are given by 0.00466 mGy.MBq{sup -1} / 0.00339 mGy.MBq{sup -1}. Approximately 21.2% of the absorbed dose is due to the bladder (content) and the remaining tissue, included in biokinetics of Tc{sup 99m} (DTPA) / Tc{sup 99m} (Mag3). The absorbed dose to the kidneys due to Tc{sup 99m} (Dmsa) is 0.17881 mGy.MBq{sup -1}. Here, 1.7% of the absorbed dose is due to the bladder, spleen, liver and the remaining tissue, included in biokinetics of Tc{sup 99m} (Dmsa). (Author)

Guidance for the management of solid waste contaminated by urine of patients after administration of radiopharmaceuticals; Conseil pour la gestion des dechets solides contamines par des urines de patients apres administration de radiopharmaceutiques

Energy Technology Data Exchange (ETDEWEB)

Touzery, C.; Prevot, S.; Perrette, B.; Boichot, C.; Berriolo-Riedinger, A.; Toubeau, M.; Riedinger, J.M.; Brunotte, F. [Centre de Lutte Contre le Cancer Georges-Francois-Leclerc, Service de Medecine Nucleaire, 21 - Dijon (France)

2003-02-01

The recent reinforcement of the French regulation on radionuclide contaminated waste brings the Nuclear Medicine Departments in charge of writing guidance intended to the personnel of the health care units. A special attention must be paid to the waste contaminated by urine of the incontinent patients. The present paper provides time duration for the collection and the storage of urine contaminated waste obtained from the simulation with literature models and data for the most frequently used radiopharmaceuticals. The validity of the results is discussed according to the parameter variations of the biokinetic models. (authors)

Biokinetic aspects of tissue-bound tritium in algae

International Nuclear Information System (INIS)

Strack, S.; Kistner, G.

1978-01-01

For the estimate of the radiation exposure of man and for the calculation of the risk of artificial tritium from nuclear power plants, organic tissue-bound tritium is of decisive importance. In model experiments, a tritium incorporation of 61 to 71% was found from tritiated water (HTO) into organic matter of planctonic algae under reproducible conditions and this was related to the theoretical value. In further experiments the tritium release from these high tritiated algae was of interest. Kept in darkness in tritium-free, non-sterile river water, so that autolytic processes and bacterial decomposition could occur, the concentration of HTO was measured over a period of three weeks. A relatively long half-life of tissue-bound tritium was found under various temperature conditions. Therefore it must be considered that a significant retention of tritium in biological matter has to be taken into account in a natural ecosystem. In streams into which the cooling water of a nuclear reactor is released all conditions are found already for a long turnover and cycling of artificial tritium in living organisms as well as the conditions for a favourable transport of tritium by food chains to man. (Auth.)

Nutrients removal from artificial bathroom greywater using Botryococcus sp. strain

Science.gov (United States)

Mohamed, RMSR; Al-Gheethi, AA; Wurochekke, AA; Maizatul, AY; Matias-Peralta, HM; Kassim, AH Mohd

2018-04-01

The discharge of untreated bathroom greywater directly into drain is a most common practice in the rural area. The uncontrolled discharge of greywater from the village houses escalates the pollution among Malaysian river and provide insanitary environment through mosquito and flies breeding grounds. Therefore, the current work aimed to investigate the potential of Botryococcus sp. for removing total nitrogen (TN), total phosphorus (TP) and total organic carbon (TOC) from artificial bathroom greywater and to determine the bio-kinetic removal rate for these parameters. The artificial bathroom greywater was prepared by using regular brands used in the community, the bathroom greywater quality was tested for BOD, COD, SS, pH, and Turbidity. The removal process was conducted in the lab scale with 108 cell mL-1 of Botryococcus sp. The removal of TN, TP and TOC was measured in interval of 3, 5 and 7 days. The results deduced that Botryococcus sp. removed 51.5% of TN, 49.5% of TP and 42.6% of TOC. Moreover, the bio-kinetic model studies, revealed that the specific removal rate of TN, TP and TOC have a significant relationship with initial concentration in the artificial greywater (R2 = 0.63, 0.95 and 0.95 respectively). The kinetic coefficient of greywater parameters removed by Botryococcus sp. was determined as k=0.357 mg TN 1 log10 cell mL-1 d-1 and km=31.33 mg L-1 (R2=0.73), k=4.58 mg TP 1 log10 cell mL-1 d-1 and km=283.86 mg L-1 (R2=0.95), k=7.9 mg TOC 1 log10 cell mL-1 d-1 and km=322.32 mg L-1 (R2=0.97). The bio-kinetic model indicated that more than 90% of TN, TP and TOC was taken place as a response for Botryococcus sp.

The conversion of exposures due to radon into the effective dose: the epidemiological approach

Energy Technology Data Exchange (ETDEWEB)

Beck, T.R. [Federal Office for Radiation Protection, Berlin (Germany)

2017-11-15

The risks and dose conversion coefficients for residential and occupational exposures due to radon were determined with applying the epidemiological risk models to ICRP representative populations. The dose conversion coefficient for residential radon was estimated with a value of 1.6 mSv year{sup -1} per 100 Bq m{sup -3} (3.6 mSv per WLM), which is significantly lower than the corresponding value derived from the biokinetic and dosimetric models. The dose conversion coefficient for occupational exposures with applying the risk models for miners was estimated with a value of 14 mSv per WLM, which is in good accordance with the results of the dosimetric models. To resolve the discrepancy regarding residential radon, the ICRP approaches for the determination of risks and doses were reviewed. It could be shown that ICRP overestimates the risk for lung cancer caused by residential radon. This can be attributed to a wrong population weighting of the radon-induced risks in its epidemiological approach. With the approach in this work, the average risks for lung cancer were determined, taking into account the age-specific risk contributions of all individuals in the population. As a result, a lower risk coefficient for residential radon was obtained. The results from the ICRP biokinetic and dosimetric models for both, the occupationally exposed working age population and the whole population exposed to residential radon, can be brought in better accordance with the corresponding results of the epidemiological approach, if the respective relative radiation detriments and a radiation-weighting factor for alpha particles of about ten are used. (orig.)

The conversion of exposures due to radon into the effective dose: the epidemiological approach

International Nuclear Information System (INIS)

Beck, T.R.

2017-01-01

The risks and dose conversion coefficients for residential and occupational exposures due to radon were determined with applying the epidemiological risk models to ICRP representative populations. The dose conversion coefficient for residential radon was estimated with a value of 1.6 mSv year -1 per 100 Bq m -3 (3.6 mSv per WLM), which is significantly lower than the corresponding value derived from the biokinetic and dosimetric models. The dose conversion coefficient for occupational exposures with applying the risk models for miners was estimated with a value of 14 mSv per WLM, which is in good accordance with the results of the dosimetric models. To resolve the discrepancy regarding residential radon, the ICRP approaches for the determination of risks and doses were reviewed. It could be shown that ICRP overestimates the risk for lung cancer caused by residential radon. This can be attributed to a wrong population weighting of the radon-induced risks in its epidemiological approach. With the approach in this work, the average risks for lung cancer were determined, taking into account the age-specific risk contributions of all individuals in the population. As a result, a lower risk coefficient for residential radon was obtained. The results from the ICRP biokinetic and dosimetric models for both, the occupationally exposed working age population and the whole population exposed to residential radon, can be brought in better accordance with the corresponding results of the epidemiological approach, if the respective relative radiation detriments and a radiation-weighting factor for alpha particles of about ten are used. (orig.)

Excretion of radionuclides in human breast milk following administration of 125I-fibrinogen, 99Tc/sup m/-MAA and 51Cr-EDTA

International Nuclear Information System (INIS)

Mattsson, S.; Johansson, L.; Nosslin, B.; Ahlgren, L.

1981-01-01

Very few biokinetic and dosimetric data for estimating the absorbed dose to a breast-feeding child are available in the literature. The few available are usually case reports. We have measured the activity concentration in breast milk from one patient after administration of 125 I-fibrinogen, from two patients after administration of 99 Tc/sup m/-macroaggregated albumin, and from one patient after administration of 51 Cr-EDTA. We have compared our data with earlier published results and estimated the absorbed dose to the breast-feeding child using biokinetic data presented in this work and recently published S-values for new-born children

The internal dosimetry code PLEIADES.

Science.gov (United States)

Fell, T P; Phipps, A W; Smith, T J

2007-01-01

The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts-the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included.

The internal dosimetry code PLEIADES

International Nuclear Information System (INIS)

Fell, T. P.; Phipps, A. W.; Smith, T. J.

2007-01-01

The International Commission on Radiological Protection (ICRP) has published dose coefficients for the ingestion or inhalation of radionuclides in a series of reports covering intakes by workers and members of the public, including children and pregnant or lactating women. The calculation of these coefficients divides naturally into two distinct parts - the biokinetic and dosimetric. This paper describes in detail the methods used to solve the biokinetic problem in the generation of dose coefficients on behalf of the ICRP, as implemented in the Health Protection Agency's internal dosimetry code PLEIADES. A summary of the dosimetric treatment is included. (authors)

Application of a canine ²³⁸Pu dosimetry model to human bioassay data

Energy Technology Data Exchange (ETDEWEB)

Hickman, Jr., A. W. [Florida Univ., Gainesville, FL (United States)

1991-08-01

Associated with the use of 2²³⁸Pu in thermoelectric power sources for space probes and power supplies for cardiac devices is the potential for human exposure to ²³⁸Pu, primarily by inhalation. In the event of human internal exposure, a means is needed for assessing the level of intake and calculating radiation doses. Several bioassay/dosimetry models have been developed for ²³⁹Pu. However, results from studies with laboratory animals have indicated that the biokinetics, and therefore the descriptive models, of ²³⁸Pu are significantly different from those for ²³⁹Pu. A canine model accounting for these differences has been applied in this work to urinary excretion data from seven humans occupationally exposed to low levels of an insoluble ²³⁸Pu compound. The modified model provides a good description of the urinary excretion kinetics observed in the exposed humans. The modified model was also used to provide estimates of the initial intakes of ²³⁸Pu for the seven individuals; these estimates ranged from 4.5 nCi (170 Bq) to 87 nCi (3200 Bq). Autopsy data on the amount and distribution of ²³⁸Pu retained in the organs may be used in the future to validate or refute both these estimates and the assumptions used to formulate the human model. Modification of the human model to simulate an injection exposure to ²³⁹Pu gave patterns of retention in the organs and urinary excretion comparable to those seen previously in humans; further modification of the model using fecal data (unavailable for the subjects of this study) is indicated.

Computational fluid dynamics modeling of Bacillus anthracis spore deposition in rabbit and human respiratory airways

Energy Technology Data Exchange (ETDEWEB)

Kabilan, S.; Suffield, S. R.; Recknagle, K. P.; Jacob, R. E.; Einstein, D. R.; Kuprat, A. P.; Carson, J. P.; Colby, S. M.; Saunders, J. H.; Hines, S. A.; Teeguarden, J. G.; Straub, T. M.; Moe, M.; Taft, S. C.; Corley, R. A.

2016-09-01

Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived respectively from computed tomography (CT) and µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation–exhalation breathing conditions using average species-specific minute volumes. Two different exposure scenarios were modeled in the rabbit based upon experimental inhalation studies. For comparison, human simulations were conducted at the highest exposure concentration used during the rabbit experimental exposures. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the nasal sinus compared to the human at the same air concentration of anthrax spores. In contrast, higher spore deposition was predicted in the lower conducting airways of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology for deposition.

Computational Fluid Dynamics Modeling of Bacillus anthracis Spore Deposition in Rabbit and Human Respiratory Airways

Energy Technology Data Exchange (ETDEWEB)

Kabilan, Senthil; Suffield, Sarah R.; Recknagle, Kurtis P.; Jacob, Rick E.; Einstein, Daniel R.; Kuprat, Andrew P.; Carson, James P.; Colby, Sean M.; Saunders, James H.; Hines, Stephanie; Teeguarden, Justin G.; Straub, Tim M.; Moe, M.; Taft, Sarah; Corley, Richard A.

2016-09-30

Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived from computed tomography (CT) or µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation-exhalation breathing conditions using average species-specific minute volumes. The highest exposure concentration was modeled in the rabbit based upon prior acute inhalation studies. For comparison, human simulation was also conducted at the same concentration. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the upper conducting airways compared to the human at the same air concentration of anthrax spores. As a result, higher particle deposition was predicted in the conducting airways and deep lung of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology.

Age-dependent doses to members of the public from intake of radionuclides: Pt. 5. Compilation of ingestion and inhalation dose coefficients

International Nuclear Information System (INIS)

1996-01-01

The present report is a compilation of age-dependent committed effective dose coefficients for ingestion and inhalation of radionuclides of the 31 elements covered in previous CRP Publications. The biokinetic models for adults given in ICRP Publication 30 are applied to calculate these dose coefficients, except that age-specific excretion rates are used and increased gastrointestinal absorption in infants is assurred. Changes in body mass, and tissue geometry in children are also taken into account. (UK)

Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models.

Science.gov (United States)

Teng, S; Tebby, C; Barcellini-Couget, S; De Sousa, G; Brochot, C; Rahmani, R; Pery, A R R

2016-08-15

Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro - in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. Copyright © 2016 Elsevier Inc. All rights reserved.

Bench-scale studies of reactor-based treatment of fuel-contaminated soils

International Nuclear Information System (INIS)

Truax, D.D.; Britto, R.; Sherrard, J.H.

1995-01-01

Biological treatment of hazardous wastes from accidental spills or underground storage tank leaks has generated interest in bioremediation as a natural, economical mechanism for site decontamination. Because of drawbacks of batch systems, and the successful use of continuous flow treatment of wastewater for several decades, it was felt that continuous treatment of such soils would be a feasible alternative treatment technique. Therefore, bench-scale bioreactor treatability studies were conducted and used contaminated soil made in the laboratory using No. 2 diesel fuel and sand. Contamination levels studied were from 1,335--6,675 mg (TPH) as derived from No. 2 fuel oil per kg sand. Variation in mean cell age was obtained between reactors, with sufficient nutrients and oxygen made available to ensure the fuel oil organics were the only limit to microbial growth. A theoretical biokinetic model was formulated based on Monod's theory of limiting substrate and continuous cultures. Biokinetic constants and removal efficiencies were evaluated. The off-gases, CO 2 , and volatile hydrocarbons were monitored for mass balance analysis of the process. The solids retention times for evaluating final TPH concentration of 100 mg/kg were also calculated. Removal efficiencies of up to 91% were attained at a loading of 1,335 mg TPH/kg wet sand, operated at a biological solid retention time (BSRT) of 60 days. Experiments also showed that TPH desorption and volatilization were not rate-limiting in the overall removal process. Sand-to-moisture ratios in excess of 3:1 were also shown to retard TPH removal rates very little. However, biokinetic constants were found to vary over a range of values. This was particularly true at varying diesel loading levels. Nevertheless, significant removal efficiency (up to 86%) was noted at the highest loading level tested, 6,675 mg TPH/kg wet sand

Continuous cell recycle fermentation

Energy Technology Data Exchange (ETDEWEB)

Warren, R K; Hill, G A; MacDonald, D G

1991-10-01

A cell recycle fermentor using a cross-flow membrane filter has been operated for extended periods. Productivities as high as 70 g/l/h were obtained at a cell concentration of 120 g/l and a product concentration of 70 g/l. The experimental results were then fitted to previously derived biokinetic models (Warren et al., 1990) for a continuous stirred tank fermentor. A good fit for growth rate was found and the cell yield was shown to decrease with product concentration. The product yield, however, was found to remain nearly constant at all cell, substrate and product concentrations. These biokinetics, along with a previous model for the membrane filter (Warren et al., 1991) were then used in a simulalation to estimate the costs of producing ethanol in a large scale system. This simulation was optimized using a variant of the steepest descent method from which a fermentor inlet substrate concentration of 150 g/l and a net cost of $CAN 253.5/1000 L ethanol were projected. From a sensitivity analysis, the yield parameters were found to have the greatest effect on ethanol net cost of the fermentor parameters, while the operating costs and the profit was found to be most sensitive to the wheat raw material cost and to the dried grains by-product value. 55 refs., 11 tabs., 7figs.

Animal study on biological responses by radon inhalation making use of waste rock which contains feeble activity of uranium (Joint research)

International Nuclear Information System (INIS)

Ishimori, Yuu; Sakoda, Akihiro; Tanaka, Hiroshi; Mitsunobu, Fumihiro; Yamaoka, Kiyonori; Kataoka, Takahiro; Yamato, Keiko; Nishiyama, Yuichi

2013-06-01

Okayama University and the Japan Atomic Energy Agency (JAEA) have carried out the collaborative study of physiological effects of inhaled radon for the low-dose range. Main assignments were as follows. Based on the clinical knowledge, Misasa Medical Center (Okayama University Hospital) clarified the issues that should be addressed. Graduate School of Health Sciences (Okayama University) supervised the research and studied the biological responses. The JAEA made the development and control of a facility for radon inhalation experiments and the investigation of biokinetics and absorbed doses of radon. From 2007 to 2011, the following results were obtained. (1) Literature on effects of radon for the low-dose range was surveyed to determine the present tasks. (2) The first Japanese large-scale facility was developed for radon inhalation experiments with small animals. (3) Relationships between radon concentration and inhalation time were widely examined to understand the change in antioxidative functions due to radon, which are the most basic parameters. (4) Inhibitory effects of radon on oxidative damages were observed using model mice with reactive oxygen- or free radical-related diseases like alcohol-induced oxidative damages and type I diabetes. (5) In order to discuss biological responses quantitatively following radon inhalation, the biokinetics of inhaled radon was examined and the model for calculation of absorbed doses for organs and tissues was obtained. (author)

Human metabolism of caesium

International Nuclear Information System (INIS)

Raeaef, C.L.; Falk, R.; Lauridsen, Bente; Rahola, T.; Soogard-Hansen, J.

2006-04-01

A study of the human biokinetics of caesium in two forms, i.) incorporated in foodstuff (137Cs in perch and mushrooms) and ii.) in ionic state ( 134 Cs in aqueous solution) has been carried out at the department of Radiation Physics in Malmoe, starting in 2001. The results of the pilot study were published in 2004, and a continuation of that study has now been carried out by means of NKS funding (NKS-B Cskinetik). The aim is to, i.) investigate whether Scandinavian populations exhibit shorter biological half-time of radiocaesium than other populations; ii.) extend the biokinetic study to additional human subjects from the other Nordic countries. Results from the continued study further indicate a near complete absorption of radiocaesium in the gastro-intestinal tract, be it in ion state or contained in food matrix. So far, the literature survey of Nordic studies on biokinetics of Cs suggests that the biological half time is somewhat shorter among Scandinavian males (84 days vs. ICRP-value of 110 days), although females do not exhibit any significant difference (64 days vs ICRP value of 65 days). (au)

Human metabolism of caesium

Energy Technology Data Exchange (ETDEWEB)

Raeaef, C.L. [Lund Univ., Dept. of Radiation Physics in Malmoe (Sweden); Falk, R. [Swedish Radiation Protection Authority (Sweden); Lauridsen, Bente [Risoe National Lab. (Denmark); Rahola, T. [STUK - Radiation and Nuclear Safety Authority (Finland); Soogard-Hansen, J. [NRPA - Norwegian Radiation Protection Authority (Norway)

2006-04-15

A study of the human biokinetics of caesium in two forms, i.) incorporated in foodstuff (137Cs in perch and mushrooms) and ii.) in ionic state ({sup 134}Cs in aqueous solution) has been carried out at the department of Radiation Physics in Malmoe, starting in 2001. The results of the pilot study were published in 2004, and a continuation of that study has now been carried out by means of NKS funding (NKS-B Cskinetik). The aim is to, i.) investigate whether Scandinavian populations exhibit shorter biological half-time of radiocaesium than other populations; ii.) extend the biokinetic study to additional human subjects from the other Nordic countries. Results from the continued study further indicate a near complete absorption of radiocaesium in the gastro-intestinal tract, be it in ion state or contained in food matrix. So far, the literature survey of Nordic studies on biokinetics of Cs suggests that the biological half time is somewhat shorter among Scandinavian males (84 days vs. ICRP-value of 110 days), although females do not exhibit any significant difference (64 days vs ICRP value of 65 days). (au)

Advanced computational modeling for in vitro nanomaterial dosimetry.

Science.gov (United States)

DeLoid, Glen M; Cohen, Joel M; Pyrgiotakis, Georgios; Pirela, Sandra V; Pal, Anoop; Liu, Jiying; Srebric, Jelena; Demokritou, Philip

2015-10-24

Accurate and meaningful dose metrics are a basic requirement for in vitro screening to assess potential health risks of engineered nanomaterials (ENMs). Correctly and consistently quantifying what cells "see," during an in vitro exposure requires standardized preparation of stable ENM suspensions, accurate characterizatoin of agglomerate sizes and effective densities, and predictive modeling of mass transport. Earlier transport models provided a marked improvement over administered concentration or total mass, but included assumptions that could produce sizable inaccuracies, most notably that all particles at the bottom of the well are adsorbed or taken up by cells, which would drive transport downward, resulting in overestimation of deposition. Here we present development, validation and results of two robust computational transport models. Both three-dimensional computational fluid dynamics (CFD) and a newly-developed one-dimensional Distorted Grid (DG) model were used to estimate delivered dose metrics for industry-relevant metal oxide ENMs suspended in culture media. Both models allow simultaneous modeling of full size distributions for polydisperse ENM suspensions, and provide deposition metrics as well as concentration metrics over the extent of the well. The DG model also emulates the biokinetics at the particle-cell interface using a Langmuir isotherm, governed by a user-defined dissociation constant, K(D), and allows modeling of ENM dissolution over time. Dose metrics predicted by the two models were in remarkably close agreement. The DG model was also validated by quantitative analysis of flash-frozen, cryosectioned columns of ENM suspensions. Results of simulations based on agglomerate size distributions differed substantially from those obtained using mean sizes. The effect of cellular adsorption on delivered dose was negligible for K(D) values consistent with non-specific binding (> 1 nM), whereas smaller values (≤ 1 nM) typical of specific high

USTUR Whole Body Case 0262: 33-y Follow-up of PuO2 In A Skin Wound and Associated Axillary Node

Energy Technology Data Exchange (ETDEWEB)

James, Anthony C.; Sasser, Lyle B.; Stuit, Dorothy B.; Wood, T. G.; Glover, Samuel E.; Lynch, Timothy P.; Dagle, Gerald E.

2008-01-28

This whole body donation case (USTUR Registrant) involved two suspected plutonium oxide (Pu) inhalation intakes, each indicated by a measurable Pu alpha activity in a single urine sample, followed about 1.5 y later by a puncture wound to the thumb while working in a Pu glovebox. The study is concerned with modeling simultaneously the biokinetics of deposition and retention in the respiratory tract and at the wound site; and the biokinetics of Pu subsequently transferred to other body organs, until the donor's death. Urine samples taken after the wound incident had readily measurable Pu alpha activity over the next 14 y, before dropping below the minimum detectable excretion rate (<0.4 mBq per day). The Registrant died about 33 y after the wound intake, at the age of 71, from hepatocellular carcinoma with extensive metastases. At autopsy, all major soft tissue organs were harvested for analysis of their Pu-238, Pu-239+240 and Am-241 content. The amount of Pu-239+240 retained at the wound site was 68 ± 7 Bq (1 SD), measured by low-energy planar Ge spectrometry. A further 56.0 ± 1.2 Bq was retained in an associated axillary lymph node, measured by radiochemistry. Simultaneous mathematical analysis (modelling) of all in vivo urinary excretion data, together with the measured lung, thoracic lymph node, wound, axillary lymph node and systemic tissue contents at death, yielded estimated intake amounts of 757 and 1504 Bq, respectively, for the first and second inhalation incidents, and 204 Bq for the total wound intake. The inhaled Pu material was highly insoluble, with an estimated long-term absorption rate from the lungs of 2 E-5 per day. The Pu material deposited at the wound site was mixed: 14% was rapidly absorbed, 49% was absorbed at the rate of about 6E-5 per day, and the remainder ( 37%) was absorbed extremely slowly (at the rate of about 5E-6 per day). Thus, it was estimated that only 40% of the Pu initially deposited in the wound had been absorbed

On the incorporation of biokinetic and mechanistic data in modeling for risk assessment

NARCIS (Netherlands)

Clewell, H.J.

2007-01-01

The goal of the studies described in this thesis was to foster the increased use of emerging scientific information and innovative methods in chemical risk assessments, in order to assure the protection of public health while limiting the economic and social consequences of over-regulation. The

Radioiodine Therapy of Hyperthyroidism. Simplified patient-specific absorbed dose planning

Energy Technology Data Exchange (ETDEWEB)

Joensson, Helene

2003-10-01

Radioiodine therapy of hyperthyroidism is the most frequently performed radiopharmaceutical therapy. To calculate the activity of {sup 131}I to be administered for giving a certain absorbed dose to the thyroid, the mass of the thyroid and the individual biokinetic data, normally in the form of uptake and biologic half-time, have to be determined. The biologic half-time is estimated from several uptake measurements and the first one is usually made 24 hours after the intake of the test activity. However, many hospitals consider it time-consuming since at least three visits of the patient to the hospital are required (administration of test activity, first uptake measurement, second uptake measurement plus treatment). Instead, many hospitals use a fixed effective half-time or even a fixed administered activity, only requiring two visits. However, none of these methods considers the absorbed dose to the thyroid of the individual patient. In this work a simplified patient-specific method for treating hyperthyroidism is proposed, based on one single uptake measurement, thus requiring only two visits to the hospital. The calculation is as accurate as using the individual biokinetic data. The simplified method is as patient-convenient and time effective as using a fixed effective half-time or a fixed administered activity. The simplified method is based upon a linear relation between the late uptake measurement 4-7 days after intake of the test activity and the product of the extrapolated initial uptake and the effective half-time. Treatments not considering individual biokinetics in the thyroid result in a distribution of administered absorbed dose to the thyroid, with a range of -50 % to +160 % compared to a protocol calculating the absorbed dose to the thyroid of the individual patient. Treatments with a fixed administered activity of 370 MBq will in general administer 250 % higher activity to the patient, with a range of -30 % to +770 %. The absorbed dose to other

Bibliographic study on molybdenum biokinetics

International Nuclear Information System (INIS)

Erzberger, A.

1988-05-01

This bibliographical study compiles and analyzes findings about the metabolism and resorption of molybdenum. Besides including studies on the physiology of molybdenum 99, a general survey is given on molybdenum in the environment and on its physiological behaviour. In particular, information on the dependence of molybdenum resorption on various factors, such as the chemical form, antagonisms etc., are gathered from literature. These factors have to be considered for sensibly carrying out necessary experiments. (orig./MG) [de

Kinetic modelling and characterization of microbial community present in a full-scale UASB reactor treating brewery effluent.

Science.gov (United States)

Enitan, Abimbola M; Kumari, Sheena; Swalaha, Feroz M; Adeyemo, J; Ramdhani, Nishani; Bux, Faizal

2014-02-01

The performance of a full-scale upflow anaerobic sludge blanket (UASB) reactor treating brewery wastewater was investigated by microbial analysis and kinetic modelling. The microbial community present in the granular sludge was detected using fluorescent in situ hybridization (FISH) and further confirmed using polymerase chain reaction. A group of 16S rRNA based fluorescent probes and primers targeting Archaea and Eubacteria were selected for microbial analysis. FISH results indicated the presence and dominance of a significant amount of Eubacteria and diverse group of methanogenic Archaea belonging to the order Methanococcales, Methanobacteriales, and Methanomicrobiales within in the UASB reactor. The influent brewery wastewater had a relatively high amount of volatile fatty acids chemical oxygen demand (COD), 2005 mg/l and the final COD concentration of the reactor was 457 mg/l. The biogas analysis showed 60-69% of methane, confirming the presence and activities of methanogens within the reactor. Biokinetics of the degradable organic substrate present in the brewery wastewater was further explored using Stover and Kincannon kinetic model, with the aim of predicting the final effluent quality. The maximum utilization rate constant U max and the saturation constant (K(B)) in the model were estimated as 18.51 and 13.64 g/l/day, respectively. The model showed an excellent fit between the predicted and the observed effluent COD concentrations. Applicability of this model to predict the effluent quality of the UASB reactor treating brewery wastewater was evident from the regression analysis (R(2) = 0.957) which could be used for optimizing the reactor performance.

Investigations on the biokinetics of carbon 14 in algae cultures

International Nuclear Information System (INIS)

Leister, W.

1981-01-01

The uptake of 14 C by Scenedesmus quadricauda is quantitatively investigated by simulation models of radio ecological relevance. Due to the complexing of the procedures in the natural ecosystem, it was only possible to consider idealized conditions. The batch culture ressembles the conditons of still waters or relatively still waters without notable water exchange. The effect of the 14 C enrichment, as well as the drastic carbon reduction in the substrate as a result of algae growth, was avoided in the modified batch culture under conditions of simultaneous substrate diffusion by means of a permeation system. The 14 C and 12 C uptake of the cells thus took place solely under the conditions of constant concentration in the culture medium. The consequences for flowing water resulting from a nuclear power plant accident are to be simulated for the extent of the 14 C uptake by green algae using the continuous culture model with dynamic 14 C exposure. The continuous infusion of 14 C in the continuous culture corresponds to the possible cases where 14 C escapes into a flowing water at a constant rate over a long period of time, whether this may be via chronical release from a nuclear power plant or by 'fallout' resulting from nuclear arms testing. The results shown lead to the conclusion that the emission of 14 C to the environment, which according to prognoses will be considerably higher after the year 2000, presents a serious radioactivity potential which man and environment will have to live with should these developments continue and the prognoses come true. (orig./MG) [de

Evaluation of absorbed dose in studies of renal function due to 123I/131I (hippuran) e 111In (DPTA)

International Nuclear Information System (INIS)

Vasquez, M.V.; Castillo, C.E.; Rojas, R.; Cabrera, C.; Abanto, D.; Morgan, A.; Diaz, E.E.

2015-01-01

The absorbed dose of the kidneys during renal function studies of adult patients is estimated through biokinetics of radiopharmaceuticals containing the 123 I/ 131 I (hippuran) e 111 In (DPTA). Using the methodology MIRD and representation Cristy-Eckerman for adult kidneys, it is shown that dosimetric contributions of organs of biokinetics 123 I/ 131 I (hippuran) e 111 In (DPTA) are significant, in estimative of dose for renal function studies. Dosimetric contributions (body and whole bladder, kidneys excluding) are given by 11.90% (for 123 I), 4.97% (for 131 I) and 28.32% (for 111 In). In all cases, the dosimetric contributions are mainly due to photons issued by the whole body

Prediction of response to continuous irradiation at low dose rate for repeated administrations in radiotherapy with beta emitters

International Nuclear Information System (INIS)

Calderon, Carlos; Gonzalez, Joaquin; Quesada, Waldo

2009-01-01

The absorbed dose to tumors after systemic administration of radiopharmaceuticals is not sufficient to achieve acceptable levels of probability of tumor control without compromising on critical tissue toxicity (kidney and / or bone marrow (BM)). There are reports of trials with multiple administrations, about tolerance level inter-administration intervals to allow recovery of the BM, with good results. The biokinetic behavior of some radiopharmaceuticals known makes possible the application of several administrations with short intervals of time.It is the present work combines two kinetic models of tumor growth and cell kinetics in the BM for predicting the response to continuous irradiation at low dose rate. The estimation of the effects of irradiation on tumor and kidneys was done using a formulation of the linear-quadratic model functions suitable for dose rate and multi-exponential repair. The estimation of the response in WB performed using a compartmental model previously reported. The absorbed dose to organs were calculated using the MIRD formulation taking into account the effect of irradiation cross. Biokinetic data were used for therapeutic radiopharmaceuticals 90Y, 131I and 177Lu, as well as radiobiological parameters reported for experimental animals. The effect on the response by the variation of inter-administration interval in slow-growing tumors and fast, so as the radiosensitive and radioresistant tumors. You can set conditions irradiation to an acceptable level of thrombocytopenia (onset and duration of the minimum in the curve) and renal irradiation below the limit of tolerance. It is possible to design experiments evaluation of therapeutic radiopharmaceuticals with a greater degree of refinement. (author)

The Mayak Worker Dosimetry System (MWDS-2013): a comparison of intakes based on urine versus autopsy data from Mayak workers using the Leggett systemic model for plutonium

International Nuclear Information System (INIS)

Birchall, A.; Dorrian, M.-D.; Suslova, K. G.; Sokolova, A. B.

2017-01-01

The Mayak Worker Dosimetry System-2013 (MWDS-2013) uses a model developed by Leggett and colleagues to represent the biokinetic behaviour of plutonium after uptake to blood. Of particular importance, with regard to estimating intakes (and doses), is the distribution of activity between urine and body organs (particularly liver and skeleton). In this study, measurement data (urine and autopsy) from around 500 Mayak workers have been used to validate use of this model. A robust method has been developed and used to estimate intakes from both urine and autopsy data separately, and the ratio of these estimates has been calculated for each worker. The geometric mean ratio has been shown to lie within a range of 0.92-1.14, depending on assumptions made. Since this range includes 1, the hypothesis that the model is unbiased with regard to estimating intakes either with urine or autopsy data cannot be rejected on the basis of these data. This lends weight to the argument for increasing the MWDS-2013 cohort to include an additional 500 workers for whom only autopsy data are available, and who have previously been excluded from the cohort. Future directions in which this work could be extended are also suggested. (authors)

Man-machine analysis of translation and work tasks of Skylab films

Science.gov (United States)

Hosler, W. W.; Boelter, J. G.; Morrow, J. R., Jr.; Jackson, J. T.

1979-01-01

An objective approach to determine the concurrent validity of computer-graphic models is real time film analysis. This technique was illustrated through the procedures and results obtained in an evaluation of translation of Skylab mission astronauts. The quantitative analysis was facilitated by the use of an electronic film analyzer, minicomputer, and specifically supportive software. The uses of this technique for human factors research are: (1) validation of theoretical operator models; (2) biokinetic analysis; (3) objective data evaluation; (4) dynamic anthropometry; (5) empirical time-line analysis; and (6) consideration of human variability. Computer assisted techniques for interface design and evaluation have the potential for improving the capability for human factors engineering.

Animal study on biological responses by radon inhalation making use of waste rock which contains feeble activity of uranium (2) (Joint research)

International Nuclear Information System (INIS)

Ishimori, Yuu; Sakoda, Akihiro; Tanaka, Hiroshi; Mitsunobu, Fumihiro; Yamaoka, Kiyonori; Kataoka, Takahiro; Etani, Reo

2016-03-01

Okayama University and the Japan Atomic Energy Agency (JAEA) have carried out the collaborative study of physiological effects of inhaled radon for the low-dose range. Main assignments were as follows. Based on the clinical knowledge, Misasa Medical Center (Okayama University Hospital) clarified the issues that should be addressed. Graduate School of Health Sciences (Okayama University) supervised the research and studied the biological responses. The JAEA made the development and control of a facility for radon inhalation experiments and the investigation of biokinetics and exposure doses of radon. From 2009 to 2013, the following results were obtained. (1) Literature on drinking effects of radon hot spring water was surveyed to determine the present tasks. (2) Under the present experimental conditions, drinking of hot spring water into which radon was intentionally introduced using the equipment in the facility did not have significant effects on mice. (3) Inhibitory effects of antioxidant pre-supplements (Vitamins C and E) and radon pre-inhalation on hepatic or renal oxidative damage were examined to make the comparison. (4) In order to discuss biological responses quantitatively following radon inhalation, the biokinetics of inhaled radon were studied. (5) Some exposure routes due to inhalation of radon or its progeny were modeled to calculate organ doses in mice. (author)

Radiation exposure by Tc-99m-methyldiphosphonate - development and use of a biophysical model for the determination of the local dose distribution in growth zones of a child's skeleton

International Nuclear Information System (INIS)

Petrausch, G.

1984-01-01

For the determination of the data necessary for dose calculations of an intraveneous application of Tc-99m-MDP in children, ages 3 months to 7 years, test data for the biokinetics of MDP in the whole body as well as in body areas with and without radioactive concentrations was determined by the use of a whole body activity counter and a gamma camera. These investigations were supplemented by laboratory data on the radioactive decay of Tc-99m-MDP in blood serum and on the urinary excretion of MDP. For the determination of the target volume of epiphyseal growth areas with radioactive concentrations distortion corrected measurements of the patient from the bone scintographs were compared to the biological data taken from our X-ray images. The radiation exposure of these growth areas was calculated with consideration of results from animal investigations as well as under the assumption that larger target volumes could be present in the patients. In the animal investigations the organ distribution of the MDP at various times after application, along with the biokinetic data of MDP in the whole body was ascertained as well as the distribution along long hollow bones. The calcium distribution was activationally analytically ascertained along long hollow bones in a young and an adult dog. It was attempted in the animal investigations to autoradiographically present the microdistribution of MDP in border regions epiphyseal cartilage/epiphyseal center and epiphyseal cartilage/metaphyseal growth plate. (orig./MG) [de

Development of an expert system for the taking into account of uncertainties in the monitoring of internal contaminations

International Nuclear Information System (INIS)

Davesne, E.; Blanchardon, E.; Casanova, P.; Chojnacki, E.; Paquet, F.

2010-01-01

Internal contaminations may result from professional exposure and they can be monitored by anthropo-radiometric and radio-toxicological measurements which are interpreted in terms of embedded activity and effective dose by means of biokinetic and dosimetric models. In spite of standards, some uncertainties in the dosimetric interpretation of radio-toxicological measurements may remain. The authors report the development of a software (OPSCI code) which takes into account uncertainties related to the worker internal dosimetry, the calculation of the minimum detectable dose related to an exposure, and the development of a data monitoring programme

ORIGINAL ARTICLES

African Journals Online (AJOL)

School ofPhysiology, Nutrition and Consumer Science, Potchefstroom University for Christian ... School of Biokinetics, Recreation and Sport Science, Potchefstroom University for ... health problem in future if preventive strategies are not.

Evaluation of absorbed dose in studies of renal function due to {sup 123}I/{sup 131}I (hippuran) e {sup 111}In (DPTA); Evaluacion de la dosis absorbida durante estudios de la funcion renal debido al {sup 123}I/{sup 131}I (hippuran) e {sup 111}In (DPTA)

Energy Technology Data Exchange (ETDEWEB)

Vasquez, M.V.; Castillo, C.E.; Rojas, R.; Cabrera, C.; Abanto, D.; Morgan, A. [Universidad Nacional de Trujillo (UNT), Area de Fisica Medica, Trujillo (Peru); Diaz, E.E., E-mail: marvva@hotmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre (Brazil)

2015-07-01

The absorbed dose of the kidneys during renal function studies of adult patients is estimated through biokinetics of radiopharmaceuticals containing the {sup 123}I/{sup 131}I (hippuran) e {sup 111}In (DPTA). Using the methodology MIRD and representation Cristy-Eckerman for adult kidneys, it is shown that dosimetric contributions of organs of biokinetics {sup 123}I/{sup 131}I (hippuran) e {sup 111}In (DPTA) are significant, in estimative of dose for renal function studies. Dosimetric contributions (body and whole bladder, kidneys excluding) are given by 11.90% (for {sup 123}I), 4.97% (for {sup 131}I) and 28.32% (for {sup 111}In). In all cases, the dosimetric contributions are mainly due to photons issued by the whole body.

USTUR whole body case 0262: 33-y follow-up of PuO{sub 2} in a skin wound and associated axillary node

Energy Technology Data Exchange (ETDEWEB)

James, A.C.; Sasser, L.B.; Stuit, D.B.; Wood, T.G. [U.S. Transuranium and Uranium Registries, College of Pharmacy, Washington State University, 1845 Terminal Drive, Suite 201, Richland, WA 99354 (United States); Glover, S.E. [Department of Mechanical, Industrial and Nuclear Engineering, University of Cincinnati, 598 Rhodes Hall, Cincinnati, OH 45221 (United States); Lynch, T.P. [Pacific Northwest National Laboratory, PO Box 999, Richland, WA 99354 (United States); Dagle, G.E. [2543 Harris Avenue, Richland, WA 99354 (United States)

2007-07-01

This whole body donation case (USTUR Registrant) involved two suspected PuO{sub 2} inhalation intakes, each indicated by a measurable Pu alpha activity in a single urine sample, followed about 1 1/2 y later by a puncture wound to the thumb while working in a Pu glovebox. The study is concerned with modelling simultaneously the biokinetics of deposition and retention in the respiratory tract and at the wound site; and the biokinetics of Pu subsequently transferred to other body organs, until the donor's death. Urine samples taken after the wound incident had readily measurable Pu alpha activity over the next 14 y, before dropping below the minimum detectable excretion rate (<0.4 mBq d{sup -1}). The Registrant died about 33 y after the wound intake, at the age of 71, from hepatocellular carcinoma with extensive metastases. At autopsy, all major soft tissue organs were harvested for analysis of their {sup 238}Pu, {sup 239+240}Pu and {sup 241}Am content. The amount of {sup 239+240}Pu retained at the wound site was 68{+-}7 Bq (1 SD), measured by low-energy planar Ge spectrometry. A further 56.0{+-}1.2 Bq was retained in an associated axillary lymph node, measured by radiochemistry. Simultaneous mathematical analysis (modelling) of all in vivo urinary excretion data, together with the measured lung, thoracic lymph node, wound, axillary lymph node and systemic tissue contents at death, yielded estimated intake amounts of 757 and 1504 Bq, respectively, for the first and second inhalation incidents, and 204 Bq for the total wound intake. The inhaled Pu material was highly insoluble, with an estimated long-term absorption rate from the lungs of 2 x 10{sup -5} d{sup -1}. The Pu material deposited at the wound site was mixed: {approx}14% was rapidly absorbed, {approx}49% was absorbed at the rate of about 6 x 10{sup -5} d{sup -1}, and the remainder ({approx}37%) was absorbed extremely slowly (at the rate of about 5 x 10{sup -6} d{sup -1}). Thus, it was estimated that only

Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models

International Nuclear Information System (INIS)

Teng, S.; Tebby, C.; Barcellini-Couget, S.; De Sousa, G.; Brochot, C.; Rahmani, R.; Pery, A.R.R.

2016-01-01

Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro – in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. - Highlights: • We could predict cell response over repeated exposure to mixtures of cosmetics. • Compounds acted independently on the cells. • Metabolic interactions impacted exposure concentrations to the compounds.

Analysis of real-time mixture cytotoxicity data following repeated exposure using BK/TD models

Energy Technology Data Exchange (ETDEWEB)

Teng, S.; Tebby, C. [Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Barcellini-Couget, S. [ODESIA Neosciences, Sophia Antipolis, 400 route des chappes, 06903 Sophia Antipolis (France); De Sousa, G. [INRA, ToxAlim, 400 route des Chappes, BP, 167 06903 Sophia Antipolis, Cedex (France); Brochot, C. [Models for Toxicology and Ecotoxicology Unit, INERIS, Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Rahmani, R. [INRA, ToxAlim, 400 route des Chappes, BP, 167 06903 Sophia Antipolis, Cedex (France); Pery, A.R.R., E-mail: alexandre.pery@agroparistech.fr [AgroParisTech, UMR 1402 INRA-AgroParisTech Ecosys, 78850 Thiverval Grignon (France); INRA, UMR 1402 INRA-AgroParisTech Ecosys, 78850 Thiverval Grignon (France)

2016-08-15

Cosmetic products generally consist of multiple ingredients. Thus, cosmetic risk assessment has to deal with mixture toxicity on a long-term scale which means it has to be assessed in the context of repeated exposure. Given that animal testing has been banned for cosmetics risk assessment, in vitro assays allowing long-term repeated exposure and adapted for in vitro – in vivo extrapolation need to be developed. However, most in vitro tests only assess short-term effects and consider static endpoints which hinder extrapolation to realistic human exposure scenarios where concentration in target organs is varies over time. Thanks to impedance metrics, real-time cell viability monitoring for repeated exposure has become possible. We recently constructed biokinetic/toxicodynamic models (BK/TD) to analyze such data (Teng et al., 2015) for three hepatotoxic cosmetic ingredients: coumarin, isoeugenol and benzophenone-2. In the present study, we aim to apply these models to analyze the dynamics of mixture impedance data using the concepts of concentration addition and independent action. Metabolic interactions between the mixture components were investigated, characterized and implemented in the models, as they impacted the actual cellular exposure. Indeed, cellular metabolism following mixture exposure induced a quick disappearance of the compounds from the exposure system. We showed that isoeugenol substantially decreased the metabolism of benzophenone-2, reducing the disappearance of this compound and enhancing its in vitro toxicity. Apart from this metabolic interaction, no mixtures showed any interaction, and all binary mixtures were successfully modeled by at least one model based on exposure to the individual compounds. - Highlights: • We could predict cell response over repeated exposure to mixtures of cosmetics. • Compounds acted independently on the cells. • Metabolic interactions impacted exposure concentrations to the compounds.

Advances in biotreatment of acid mine drainage and biorecovery of metals: 2. Membrane bioreactor system for sulfate reduction.

Science.gov (United States)

Tabak, Henry H; Govind, Rakesh

2003-12-01

Several biotreatmemt techniques for sulfate conversion by the sulfate reducing bacteria (SRB) have been proposed in the past, however few of them have been practically applied to treat sulfate containing acid mine drainage (AMD). This research deals with development of an innovative polypropylene hollow fiber membrane bioreactor system for the treatment of acid mine water from the Berkeley Pit, Butte, MT, using hydrogen consuming SRB biofilms. The advantages of using the membrane bioreactor over the conventional tall liquid phase sparged gas bioreactor systems are: large microporous membrane surface to the liquid phase; formation of hydrogen sulfide outside the membrane, preventing the mixing with the pressurized hydrogen gas inside the membrane; no requirement of gas recycle compressor; membrane surface is suitable for immobilization of active SRB, resulting in the formation of biofilms, thus preventing washout problems associated with suspended culture reactors; and lower operating costs in membrane bioreactors, eliminating gas recompression and gas recycle costs. Information is provided on sulfate reduction rate studies and on biokinetic tests with suspended SRB in anaerobic digester sludge and sediment master culture reactors and with SRB biofilms in bench-scale SRB membrane bioreactors. Biokinetic parameters have been determined using biokinetic models for the master culture and membrane bioreactor systems. Data are presented on the effect of acid mine water sulfate loading at 25, 50, 75 and 100 ml/min in scale-up SRB membrane units, under varied temperatures (25, 35 and 40 degrees C) to determine and optimize sulfate conversions for an effective AMD biotreatment. Pilot-scale studies have generated data on the effect of flow rates of acid mine water (MGD) and varied inlet sulfate concentrations in the influents on the resultant outlet sulfate concentration in the effluents and on the number of SRB membrane modules needed for the desired sulfate conversion in

Dimer of the peptide cycle (Ar-Gly-Asp-D-Phe-Lys) radiolabeled with {sup 99m}Tc for the integrin s over-expression image: formulation, biokinetics and dosimetry; Dimero del peptido ciclo(Arg-Gly-Asp-D-Phe-Lys) radiomarcado con {sup 99m}Tc para la imagen de sobre-expresion de integrinas: formulacion, biocinetica y dosimetria

Energy Technology Data Exchange (ETDEWEB)

Ortiz A, Z.

2013-07-01

In breast cancer, α(v)β(3) and/or α(v)β(5) integrin s are over-expressed in both endothelial and tumour cells. Radiolabeled peptides based on the RGD (Arg-Gly-Asp) sequence are radiopharmaceuticals with high affinity and selectivity for those integrin s. The RGD-dimer peptide (E-[c(RGDfK)]{sub 2}) radiolabeled with {sup 99m}Tc has been reported as a radiopharmaceutical with 10-fold higher affinity for the α(v)β(3) integrin as compared to the RGD-monomer. EDDA (Ethylenediamine-N,N-diacetic acid) is a hydrophilic molecule that may favours renal excretion when used as coligand in the {sup 99m}Tc labelling of HYNIC-peptides and can easily be formulated in a lyophilized kit. Aim: Establish a biokinetic model for {sup 99m}Tc-EDDA/HYNIC-E-[c(RGDfK)]{sub 2} prepared from lyophilized kits and evaluate the dosimetry as breast cancer imaging agent. Methods: {sup 99m}Tc labelling was performed by addition of sodium pertechnetate solution and 0.2 M phosphate buffer ph 7.0 to a lyophilized formulation containing E-[c(RGDfK)]{sub 2}, EDDA, tricine, mannitol and stannous chloride. Radiochemical purity was evaluated by reversed phase HPLC and ITLC-SG analyses. Stability studies in human serum were carried out by size-exclusion HPLC. In-vitro cell uptake was tested using breast cancer cells (MCF7, T47D and MDA-MB-231) with blocked and non-blocked receptors. Biodistribution and tumour uptake were determined in MCF7 tumour-bearing nude mice with blocked and non-blocked receptors, and images were obtained using a micro-SPECT/CT. Whole-body images from seven healthy women were acquired at 1, 3, 6 and 24 h after {sup 99m}Tc-EDDA/HYNIC-E-[c(RGDfK)]{sub 2} administration obtained with radiochemical purities of >94 %. Regions of interest (ROIs) were drawn around source organs on each time frame. Each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-EDDA/HYNIC-E-[c(RGDfK)]{sub 2} time-activity curves in each

Modeling metal bioaccumulation in the invasive mussels Dreissena polymorpha and Dreissena rostriformis bugensis in the rivers Rhine and Meuse.

Science.gov (United States)

Le, T T Yen; Leuven, Rob S E W; Hendriks, A Jan

2011-12-01

The metal-specific covalent index and the species-specific size-based filtration rate were integrated into a biokinetic model estimating metal bioaccumulation in mussels from the dissolved phase and phytoplankton. The model was validated for zebra (Dreissena polymorpha) and quagga (Dreissena rostriformis bugensis) mussels in the rivers Rhine and Meuse, the Netherlands. The model performed well in predicting tissue concentrations in different-sized zebra mussels from various sampling sites for (55) Mn, (56) Fe, (59) Co, (60) Ni, (82) Se, (111) Cd, (118) Sn, and (208) Pb (r(2) =0.71-0.99). Performance for (52) Cr, (63) Cu, (66) Zn, (68) Zn, and (112) Cd was moderate (r(2) quagga mussels, approximately 73 to 94% of the variability in concentrations of (82) Se, (111) Cd, (112) Cd, and (208) Pb was explained by the model (r(2) =0.73-0.94), followed by (52) Cr, (55) Mn, (56) Fe, (60) Ni, and (63) Cu (r(2) =0.48-0.61). Additionally, in both zebra and quagga mussels, average modeled concentrations were within approximately one order of magnitude of the measured values. In particular, in zebra mussels, estimations of (60) Ni and (82) Se concentrations were equal to 51 and 76% of the measurements, respectively. Higher deviations were observed for (52) Cr, (59) Co, (55) Mn, (56) Fe, (111) Cd, (63) Cu, and (112) Cd (underestimation), and (66) Zn, (68) Zn, (208) Pb, and (118) Sn (overestimation). For quagga mussels, modeled concentrations of (66) Zn and (68) Zn differed approximately 14% from the measured levels. Differences between predictions and measurements were higher for other metals. Copyright © 2011 SETAC.

Prediction of time-integrated activity coefficients in PRRT using simulated dynamic PET and a pharmacokinetic model.

Science.gov (United States)

Hardiansyah, Deni; Attarwala, Ali Asgar; Kletting, Peter; Mottaghy, Felix M; Glatting, Gerhard

2017-10-01

To investigate the accuracy of predicted time-integrated activity coefficients (TIACs) in peptide-receptor radionuclide therapy (PRRT) using simulated dynamic PET data and a physiologically based pharmacokinetic (PBPK) model. PBPK parameters were estimated using biokinetic data of 15 patients after injection of (152±15)MBq of 111 In-DTPAOC (total peptide amount (5.78±0.25)nmol). True mathematical phantoms of patients (MPPs) were the PBPK model with the estimated parameters. Dynamic PET measurements were simulated as being done after bolus injection of 150MBq 68 Ga-DOTATATE using the true MPPs. Dynamic PET scans around 35min p.i. (P 1 ), 4h p.i. (P 2 ) and the combination of P 1 and P 2 (P 3 ) were simulated. Each measurement was simulated with four frames of 5min each and 2 bed positions. PBPK parameters were fitted to the PET data to derive the PET-predicted MPPs. Therapy was simulated assuming an infusion of 5.1GBq of 90 Y-DOTATATE over 30min in both true and PET-predicted MPPs. TIACs of simulated therapy were calculated, true MPPs (true TIACs) and predicted MPPs (predicted TIACs) followed by the calculation of variabilities v. For P 1 and P 2 the population variabilities of kidneys, liver and spleen were acceptable (v10%). Treatment planning of PRRT based on dynamic PET data seems possible for the kidneys, liver and spleen using a PBPK model and patient specific information. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Development of a definitive internal dosimetry code

International Nuclear Information System (INIS)

Miller, G.; Inkret, W.C.; Schillaci, M.E.

1996-01-01

Internal dosimetry may be divided into tow main problems: (1) the forward (scientific) problem of determining biokinetics models that describe how radionuclides are taken into the body, distributed in body tissues, and excreted, and (2) the inverse (mathematical) problem: given the measured amounts in excreta and assuming a biokinetic model, to determine the times and amounts of intakes into the body. The inverse problem of internal dosimetry is, in fact, a generic problem studied in other fields (e.g., image reconstruction, spectral deconvulution, and model parameter fitting). We have developed a code for plutonium internal dosimetry using the maximum entropy method, a method for solving underdetermined inverse problems with a positivity constraint. Within the framework of Bayesian statistics, we believe the definitive approach is to examine the Bayesian posterior probability describing the probability of an intake scenario (X i ) read ( ... ) as open-quotes the set of,close quotes where X i denotes the intake amount that occurs on the with day. For plutonium, for a worker with a long employment history, this is a very high dimensional probability space, since there may be on the order of 10,000 days when intakes may have occurred. Within this high dimensional space, we calculate the mean intake scenario as i > where denotes the expectation value over the posterior probability distribution. Similarly, we calculate uncertainties and other relevant quantities, such as X 2 , as expectation values over the posterior distribution. Thanks to a recent breakthrough in describing the mathematical structure of the intake process (a Poisson sum representation of intakes), we have developed the initial version of a Bayesian expectation-value algorithm for internal dosimetry reconstructions

Determining ethnic-, gender-, and age-specific waist circumference ...

African Journals Online (AJOL)

2012-11-06

Nov 6, 2012 ... 1Physical Activity Sport and Recreation, School of Biokinetics, ... 2Hypertension in Africa Research Team, School for Physiology, Nutrition and Consumer Sciences ..... factors may be coping strategies that are utilised when.

International comparability of health professions: Bridging the gap ...

African Journals Online (AJOL)

... using the Google scholar search engine: Pubmed, Medline, Science Direct, ... Key search words were “biokinetics,” “exercise therapy” and “kinesiotherapy. ... is medicine,” academic curriculum, clinical training and scope of profession.

Short Report

African Journals Online (AJOL)

2016-10-02

Oct 2, 2016 ... considers contextual factors, such as environmental and personal factors. ... The documents were completed by ... A total of 30 senior nursing, physiotherapy and biokinetics students were divided into groups and interacted ...

Using biodynamic models to reconcile differences between laboratory toxicity tests and field biomonitoring with aquatic insects

Science.gov (United States)

Buchwalter, D.B.; Cain, D.J.; Clements, W.H.; Luoma, S.N.

2007-01-01

Aquatic insects often dominate lotic ecosystems, yet these organisms are under-represented in trace metal toxicity databases. Furthermore, toxicity data for aquatic insects do not appear to reflect their actual sensitivities to metals in nature, because the concentrations required to elicit toxicity in the laboratory are considerably higher than those found to impact insect communities in the field. New approaches are therefore needed to better understand how and why insects are differentially susceptible to metal exposures. Biodynamic modeling is a powerful tool for understanding interspecific differences in trace metal bioaccumulation. Because bioaccumulation alone does not necessarily correlate with toxicity, we combined biokinetic parameters associated with dissolved cadmium exposures with studies of the subcellular compartmentalization of accumulated Cd. This combination of physiological traits allowed us to make predictions of susceptibility differences to dissolved Cd in three aquatic insect taxa: Ephemerella excrucians, Rhithrogena morrisoni, and Rhyacophila sp. We compared these predictions with long-term field monitoring data and toxicity tests with closely related taxa: Ephemerella infrequens, Rhithrogena hageni, and Rhyacophila brunea. Kinetic parameters allowed us to estimate steady-state concentrations, the time required to reach steady state, and the concentrations of Cd projected to be in potentially toxic compartments for different species. Species-specific physiological traits identified using biodynamic models provided a means for better understanding why toxicity assays with insects have failed to provide meaningful estimates for metal concentrations that would be expected to be protective in nature. ?? 2007 American Chemical Society.

Uncertainty and sensitivity analysis of control strategies using the benchmark simulation model No1 (BSM1).

Science.gov (United States)

Flores-Alsina, Xavier; Rodriguez-Roda, Ignasi; Sin, Gürkan; Gernaey, Krist V

2009-01-01

The objective of this paper is to perform an uncertainty and sensitivity analysis of the predictions of the Benchmark Simulation Model (BSM) No. 1, when comparing four activated sludge control strategies. The Monte Carlo simulation technique is used to evaluate the uncertainty in the BSM1 predictions, considering the ASM1 bio-kinetic parameters and influent fractions as input uncertainties while the Effluent Quality Index (EQI) and the Operating Cost Index (OCI) are focused on as model outputs. The resulting Monte Carlo simulations are presented using descriptive statistics indicating the degree of uncertainty in the predicted EQI and OCI. Next, the Standard Regression Coefficients (SRC) method is used for sensitivity analysis to identify which input parameters influence the uncertainty in the EQI predictions the most. The results show that control strategies including an ammonium (S(NH)) controller reduce uncertainty in both overall pollution removal and effluent total Kjeldahl nitrogen. Also, control strategies with an external carbon source reduce the effluent nitrate (S(NO)) uncertainty increasing both their economical cost and variability as a trade-off. Finally, the maximum specific autotrophic growth rate (micro(A)) causes most of the variance in the effluent for all the evaluated control strategies. The influence of denitrification related parameters, e.g. eta(g) (anoxic growth rate correction factor) and eta(h) (anoxic hydrolysis rate correction factor), becomes less important when a S(NO) controller manipulating an external carbon source addition is implemented.

Assessment of fetal activity concentration and fetal dose for selected radionuclides based on animal and human data

International Nuclear Information System (INIS)

Roedler, H.D.

1987-01-01

Biokinetic data of selected radionuclide compounds from investigations in man and animal were taken from literature references with the purpose to provide a basis for a comparative assessment of fetal and adult radiation doses after intake or administration of radionuclides. The following ratios of fetal to adult doses were derived from human data: 0.5 for caesium 137 and total body, 2.3 for iron 59 and liver, 0.06 - 0.3 - 1.1 for iodine 131 and thyroid, and 0.1 - 0.3 for strontium 90 and bone. The ratios of activity concentrations in fetal and adult tissues are of considerable variability - up to three orders of magnitude. Further studies on fetal and adult biokinetics specifically designed for comparative dose assessment are indispensable. 106 refs.; 6 tabs

TLD estimation of absorbed dose for 131I on the surface of biological organs of REMCAL phantom

International Nuclear Information System (INIS)

Tandon, Pankaj; Gaur, P.K.; Bhatt, B.C.; Soni, P.S.

2001-01-01

In nuclear medicine, the accuracy of absorbed dose of an internally distributed radiopharmaceuticals estimated by the MIRD (medical internal radiation dose) method depends on the cumulated activity of the source organs and their mass. The usual method for obtaining the cumulated activities are: 1) direct measurements by a) positron emission tomography (PET) and b) single photon emission computed tomography (SPECT) 2) extrapolation from animal data and 3) calculations based on the mathematical biokinetic model. Among these methods, extrapolation of animal data to humans includes inevitable inaccuracy due to large interspecies metabolic differences with regard to the administered radiochemical. Biokinetic modeling requires adequate knowledge of various kinetic parameters, which is based on some biological assumptions. Direct measurements can provide cumulated distributions with fewer biological assumptions. But direct measurements of PET/SPECT are difficult to perform routinely. A method has been developed to obtain the surface dose of different biological organs by using TLDs. Here, a number of TLDs are placed just above the surface of the biological organs of the REMCAL Alderson human phantom filled with water. Firstly, investigation of the accuracy of this method by calibration studies using the said phantom, which is having the entire biological organ intact and simulate the organs as human body is done. These organs are filled with the known activity of the radioisotope. In the present study, estimation of radiation dose received by fifteen different target organs, when the known activity was filled in the three major organs of interest was carried out

Biodistribution dosimetric study of radiopharmaceutical {sup 99mT}c Ixolaris in mice for melanoma diagnosis by molecular image and translational model for human beings; Estudo dosimetrico da biodistribuicao do radiofarmaco Ixolaris-{sup 99m}Tc em camundongos para diagnostico de melanoma atraves de imagem molecular e modelo translacional para humanos

Energy Technology Data Exchange (ETDEWEB)

Soriano, Sarah Canuto Silva

2015-07-01

The labeling of Ixolaris with {sup 99m}Tc was developed by Barboza et.al. (2013) aiming its use primarily in glioblastoma and after in melanoma diagnosis, a less common but very aggressive cancer and with high mortality rate. Preliminary tests on animals have proven its effectiveness of labeling but a dosimetric study to human clinical trials should be performed. This study aimed to: (1) determine the biokinetic model for the radiotracer {sup 99m}Tc-Ixolaris in mice by imaging dosimetry method; and (2) estimate the absorbed and effective dose resulting from the use of a new radiopharmaceutical for melanoma and metastases diagnosis in human beings, since a dosimetric study of new radiopharmaceuticals in animals is necessary to test them subsequently in humans and apply for registration in ANVISA. According to SPECT images, was found a latency period of 15 to 21 days for the development of lung metastasis in mice. Three C57BL6 mice, one control animal, and two animals with induced cell line B16-F10 murine melanoma were tested. The {sup 99m}Tc-Ixolaris radiopharmaceutical was administered intravenously in a caudal vein, and SPECT images were acquired 0.5 h, 1.5 h, 2.5 h, 3.5 h and 24 h post-administration for analysis and biodistribution quantification. The biokinetic model was determined and thus, obtained cumulative activity in order to estimate the absorbed dose in each organ. The mass and metabolic differences between mice and humans were considered and used to extrapolate the data acquired at different scales. Based on dose factors provided by the software MIRDOSE and Olinda (S factor), absorbed doses in irradiated target organs were calculated for the source organs, and finally the effective dose was estimated. The results indicate that for diagnostic exams conducted in human melanoma patients by administering approximately 25.7 MBq the estimated effective dose was 4.3 mSv. Comparing with effective doses obtained in other diagnostic techniques with {sup 99m

Relationships between overweight, obesity and physical fitness of nine

African Journals Online (AJOL)

2009-10-08

Oct 8, 2009 ... intervention strategies are recommended to improve the quality of life of such childre,n ... a School of Biokinetics, Recreation and Sport Science, North West University, ... Health and Nutrition Examination Survey (NHANES) III.

Biokinetics and Biodynamics of Nanomaterial Interactions

Science.gov (United States)

2009-09-30

HEK viability. The medium from each treatment set of the dosed cells was removed, pooled into a microfuge tube , and quickly frozen to -80ºC until...Trump’s fixative at 4ºC. The cells were rinsed in 0.1M phosphate buffer (pH 7.2), pelleted in a microfuge tube , resuspended, and quickly pelleted in 3...formulation on in vitro human skin localized NP in the upper stratum corneum with minimal penetration (Cross et al., 2007) and microfine zinc oxide with a

the Sweet Hearts biokinetics pilot study

African Journals Online (AJOL)

Kathryn van Boom

2Department of Sport Management, Faculty of Business and Management. Sciences ... (DoH) - outlines three main public health strategies: 1) prevent. NCDs and ... physical activity and healthy nutritional habits in those who participated.

Assessment of Dose to the Nursing Infant from Radionuclides in Breast Milk

Energy Technology Data Exchange (ETDEWEB)

Leggett, Richard Wayne [ORNL; Eckerman, Keith F [ORNL

2010-03-01

A computer software package was developed to predict tissue doses to an infant due to intake of radionuclides in breast milk based on bioassay measurements and exposure data for the mother. The package is intended mainly to aid in decisions regarding the safety of breast feeding by a mother who has been acutely exposed to a radionuclide during lactation or pregnancy, but it may be applied to previous intakes during the mother s adult life. The package includes biokinetic and dosimetric information needed to address intake of Co-60, Sr-90, Cs-134, Cs-137, Ir-192, Pu-238, Pu-239, Am-241, or Cf-252 by the mother. It has been designed so that the library of biokinetic and dosimetric files can be expanded to address a more comprehensive set of radionuclides without modifying the basic computational module. The methods and models build on the approach used in Publication 95 of the International Commission on Radiological Protection (ICRP 2004), Doses to Infants from Ingestion of Radionuclides in Mothers Milk . The software package allows input of case-specific information or judgments such as chemical form or particle size of an inhaled aerosol. The package is expected to be more suitable than ICRP Publication 95 for dose assessment for real events or realistic planning scenarios in which measurements of the mother s excretion or body burden are available.

Use of I-131- CRTX for targeting malignant adenocarcinoma in mice: biodistribution and radiation dosimetry

International Nuclear Information System (INIS)

Santos, Raquel Gouvea dos; Soares, Marcella Araugio; Andrade, Henrique Martins de; Santos, Marcos Antonio da Cunha

2008-01-01

Snake venoms molecules have been shown to play a role not only in the survival and proliferation of tumour cells but also in the processes of tumour cell adhesion, migration and angiogenesis. We have shown that 125 I-Crtx, a radiolabeled version of a protein derived from Crotalus durissus terrificus snake venom (Cdt), specifically binds to tumor and triggers apoptotic death. This study reports the biokinetic profile of 99m Tc-Cdt and 125/131 I-Crtx in Swiss mice bearing Ehrlich solid tumor and MIRD formulation was applied to calculate the absorbed radiation doses for various organs and tumor site. Biokinetic evaluations were performed up to 24 h after intravenous (i.v) or intratumor (i.tu.) injection of 99m Tc-Cdt or 125/131 I-Crtx. Time-activity curves were generated for the main organs by fitting the organ specific mass mean counts. The radiation dose from 131 I-Crtx was calculated based on non penetrating radiation in the mouse model. Biokinetics data from 99m Tc-Cdt after i.v. injection in mice tumor model showed rapid blood clearance (T 1/2 = 36.1 ± 2.4 min.), slow tumor clearance (T 1/2 : 108.3 ± 19.5 min.) and indicated the kidneys as the main excretion pathway. Interaction studies in vitro demonstrated that 125 I-Crtx recognize specific sites on Erlich tumor cell membrane. Upon intravenous and intratumor administration of 131 I-Crtx in mice bearing Erlich tumor, it was observed high uptake in tumor site in vivo (Ã =72kBq x h/g) resulting in a high absorbed dose radiation to tumor site. Distributions of 125/131 I-Crtx i.v. were only significant in tumor, stomach, liver and kidneys, reflecting non-specific uptake of Crtx in normal excretion tissues in vivo. Intratumoral administration reduced significantly the radiation dose to the kidneys (42-fold lower) and increased the uptake by the tumor site (128- fold higher). 131 I control was run in a parallel experiment and showed no significant tumor uptake. In conclusion, 131 I-Crtx had a high concentration in

The measurement of thoron (220Rn) concentration in indoor air continuously using pylon model WLx

International Nuclear Information System (INIS)

Hasnel Sofyan

2011-01-01

The concentration of thoron ( 220 Rn) in particular location can be higher than radon ( 220 Rn), however, its presence is always neglected. This might be due to the difficulties in calibration and discrimination between radon and thoron. From biokinetic and dosimetric model, it has been known that the dominant contribution of thoron to the effective dose is in the lungs. UNSCEAR estimates the doses contribution of thoron and its progenies is between 5-10% of the annual dose received by the general public and the risk level is 4.4 times greater than radon and progenies. Therefore, it is necessary to study the thoron concentration in indoor air and workplaces. Radon-thoron concentration in indoor air can be determined by direct methods using Pylon Model WLx device and passive methods using Solid State Nuclear Track Detector (SSNTDs). In this research the measurement of thoron was carried out continuously using Pylon Model WLx equipment that is sensitive to radon for 24, 65, 72, 116 and 154 hours in different rooms. The measurement result showed that the mean value of thoron working level (WL) concentration obtained in room-1 was 2.53 ± 0.67 Bq/m 3 with maximum and minimum of thoron concentrations were 3.37 and 2.22 Bq/m 3 respectively. From the measurement in different locations, it was obtained that the largest and smallest average concentrations of thoron progenies were 0.83 ± 0.23 Bq/m 3 and 0.29 ± 0.64 Bq/m 3 , while the maximum and minimum concentration values were 7.80 Bq/m 3 and 0.01 Bq/m 3 respectively. Pylon Model WLx device is not enables to be used for longer and large scale survey area concurrently, so the SSNTDs which is sensitive to the emission of alpha particles and can measure cumulative thoron concentrations is required. (author)

Bioaccumulation and retention kinetics of cadmium in the freshwater decapod Macrobrachium australiense

Energy Technology Data Exchange (ETDEWEB)

Cresswell, Tom, E-mail: tom.cresswell@ansto.gov.au [Centre for Environmental Contaminants Research, CSIRO Land and Water, Locked Bag 2007, Kirrawee, NSW 2232 (Australia); School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC 3083 (Australia); Simpson, Stuart L. [School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC 3083 (Australia); Smith, Ross E.W. [Hydrobiology, Lang Parade, Auchenflower, QLD 4066 (Australia); Nugegoda, Dayanthi [School of Applied Sciences, RMIT University, Plenty Road, Bundoora, VIC 3083 (Australia); Mazumder, Debashish [Institute for Environmental Research, ANSTO, Locked Bag 2001, Kirrawee, NSW 2232 (Australia); Twining, John [Austral Radioecology, Oyster Bay, NSW, 2225 (Australia)

2014-03-01

Highlights: • Sources and mechanisms of Cd bioaccumulation were examined using radiotracers. • Macrobrachium australiense readily accumulated cadmium from the dissolved phase. • Assimilation efficiencies were comparable for sediment and algae. • A biokinetic model predicted ingestion accounted for majority of bioaccumulated Cd. - Abstract: The potential sources and mechanisms of cadmium bioaccumulation by the native freshwater decapods Macrobrachium species in the waters of the highly turbid Strickland River in Papua New Guinea were examined using {sup 109}Cd-labelled water and food sources and the Australian species Macrobrachium australiense as a surrogate. Synthetic river water was spiked with environmentally relevant concentrations of cadmium and animals were exposed for 7 days with daily renewal of test solutions. Dietary assimilation of cadmium was assessed through pulse-chase experiments where prawns were fed separately {sup 109}Cd-labelled fine sediment, filamentous algae and carrion (represented by cephalothorax tissue of water-exposed prawns). M. australiense readily accumulated cadmium from the dissolved phase and the uptake rate increased linearly with increasing exposure concentration. A cadmium uptake rate constant of 0.10 ± 0.05 L/g/d was determined in synthetic river water. During depuration following exposure to dissolved cadmium, efflux rates were low (0.9 ± 5%/d) and were not dependent on exposure concentration. Assimilation efficiencies of dietary sources were comparable for sediment and algae (48–51%), but lower for carrion (28 ± 5%) and efflux rates were low (0.2–2.6%/d) demonstrating that cadmium was well retained by M. australiense. A biokinetic model of cadmium accumulation by M. australiense predicted that for exposures to environmentally relevant cadmium concentrations in the Strickland River, uptake from ingestion of fine sediment and carrion would be the predominant sources of cadmium to the organism. The model predicted

Syntheses of α and γ-tocopherols selectively labelled with deuterium

International Nuclear Information System (INIS)

Hughes, L.; Slaby, M.; Burton, G.W.; Ingold, K.U.

1990-01-01

Four deuterium-substituted α-tocopherols (dideutero-RRR, nonadeutero-ambo, nonadeutero-all-rac and undecadeutero-all-rac) and a dideutro-RRR-γ-tocopherol have been synthesized for use in studies of the biokinetics, bioavailability and metabolism of vitamin E. (author)

Radiation dose estimates for the fetus from intakes of gallium citrate by the mother

International Nuclear Information System (INIS)

Watson, E.E.

1992-01-01

Information about the distribution and retention of Ga 67 in the pregnant woman is limited and must be extrapolated from animal data. Studies have shown that gallium administered as citrate crosses the placenta into the fetus; however, the concentration in the placenta appears to be considerably greater than that in the fetus. Little is known about the retention of gallium in the fetus and placenta. In this paper, available data on the concentrations in the placenta and fetus are combined with data on the biokinetics of gallium in the woman to provide a model for dose calculation. The absorbed fractions calculated from the pregnant woman models developed by the Radiopharmaceutical Internal Dose Information Center will be used to provide dose estimates for the radioisotopes of gallium. (author)

Copper complex N(4)-ortho-toluyl-2-acetylpyridine thiosemicarbazone - ({sup 64}Cu)(H2Ac4oT)Cl - internal dosimetry: animal model and human extrapolation

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, Josianne L.; Silva, Paulo R.O.; Santos, Raquel G.; Ferreira, Andrea V., E-mail: jlr@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2011-07-01

Thiosemicarbazones have attracted great pharmacological interest because of their biological properties, such as cytotoxic activity against multiple strains of human tumors. Due to the excellent properties of {sup 64}Cu, the copper complex N(4)-ortho-toluyl-2-acetylpyridine thiosemicarbazone (({sup 64}Cu)(H2Ac4oT)Cl) was developed for tumor detection by positron emission tomography. The radiopharmaceuticals were produced in the nuclear reactor TRIGA-IPR-R1 from CDTN. At the present work, ({sup 64}Cu)(H2Ac4oT)Cl biokinetic data (evaluated in mice bearing Ehrlich tumor) were treated by MIRD formalism to perform Internal Dosimetry studies. Doses in several organs of mice were determinate, as well as in implanted tumor, for ({sup 64}Cu)(H2Ac4oT)Cl. Doses results obtained for animal model were extrapolated to humans assuming a similar concentration ratio among various tissues between mouse and human. In the extrapolation, it was used human organ masses from Cristy/Eckerman phantom. Both penetrating and non-penetrating radiation from {sup 64}Cu in the tissue were considered in dose calculations. (author)

Browse Title Index

African Journals Online (AJOL)

Items 251 - 290 of 290 ... Vol 23, No 1 (2011), The potential market demand for biokinetics in the ... The role of physical activity during pregnancy in determining maternal ... Vol 25, No 1 (2013), The state of women's rugby union in South Africa: ...

Browse Title Index

African Journals Online (AJOL)

Items 51 - 100 of 508 ... Vol 39, No 1:2 (2017), An outdoor adventure programme infused with olympic ... Vol 33, No 3 (2011), Benefits of team sport for organisations, Abstract ... Vol 27, No 2 (2005), Biokinetics – the development of a health ...

African Journal for Physical Activity and Health Sciences - Vol 23 ...

African Journals Online (AJOL)

A comparative overview of exercise and health related professions: Athletic training, clinical exercise physiology and biokinetics · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. T.J. Ellapen, Y. Paul, M. Swanepoel, G.L. Strydom, 1-12 ...

Development and evaluation of a technique for in vivo monitoring of 60Co in the lungs

International Nuclear Information System (INIS)

Mello, J.Q. de; Lucena, E.A.; Dantas, A.L.A.; Dantas, B.M.

2015-01-01

60 Co is a fission product of 235 U and represents a risk of internal exposure of workers in nuclear power plants, especially those involved in the maintenance of potentially contaminated parts and equipment. The control of 60 Co intake by inhalation can be performed through in vivo monitoring. This work describes the evaluation of a technique through the minimum detectable activity and the corresponding minimum detectable effective doses, based on biokinetic and dosimetric models of 60 Co in the human body. The results allow to state that the technique is suitable either for monitoring of occupational exposures or evaluation of accidental intakes. (author)

Development and evaluation of a technique for in vivo monitoring of {sup 60}Co in the lungs

Energy Technology Data Exchange (ETDEWEB)

Mello, J.Q. de; Lucena, E.A.; Dantas, A.L.A.; Dantas, B.M., E-mail: bmdantas@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

2015-07-01

{sup 60}Co is a fission product of {sup 235}U and represents a risk of internal exposure of workers in nuclear power plants, especially those involved in the maintenance of potentially contaminated parts and equipment. The control of {sup 60}Co intake by inhalation can be performed through in vivo monitoring. This work describes the evaluation of a technique through the minimum detectable activity and the corresponding minimum detectable effective doses, based on biokinetic and dosimetric models of {sup 60}Co in the human body. The results allow to state that the technique is suitable either for monitoring of occupational exposures or evaluation of accidental intakes. (author)

Biokinetic of plutonium in human beings. Analysis and modification of ICRP 67 model; Biocinetica del plutonio nell'organismo umano. Analisi e modifica del modello ICRP 67

Energy Technology Data Exchange (ETDEWEB)

Luciani, A.; Castellani, C.M. [ENEA, Divisione Protezione dell' Uomo e degli Ecosistemi, Centro Ricerche Ezio Clementel, Bologna (Italy)

2001-07-01

A preliminary research of the available data and empirical functions for the plutonium excretion after injection was carried out. The ICRP model presented in the Publication no. 67 was then analyzed comparing its predictions for the activity in urine and, at a lesser extent, in feces and blood, with the collected data and empirical curves. The model was modified and an optimized age-related compartmental model was developed. A new skeletal model recently developed was also introduced and age depending bone remodelling rates were assumed on the basis of the ICRP Publication 70. This model provides a better agreement with measured urinary excretion data than the current ICRP 67 model, avoiding unphysiological assumptions such as the transfer of activity from soft tissue to urinary bladder, that were part of the ICRP model. The new optimized model predictions of the activity in faeces and in blood after an injection are also closer to the available data than the ICRP 67 estimations. A good agreement with the partitioning factor of plutonium between skeleton and liver obtained from different autopsy studies was also observed. [Italian] E' stata effettuata preliminarmente una ricerca bibliografica dei dati e delle funzioni di escrezione del plutonio attualmente disponibili in letteratura. Sulla base dei risultati di tale ricerca e' stato verificato il modello proposto dall'ICRP nella Pubblicazione n. 67. Tale modello e' stato quindi modificato al fine non solo di avere una piu' realistica descrizione dei valori predetti per l'escrezione urinaria, ma anche di modellare la cinetica del plutonio evitando quelle assunzioni introdotte appositamente nel modello dell'ICRP per correggere le previsini del modello ma che mancano di una chiara spiegazione di carattere fisiologico. Esso fornisce valutazioni piu' realistiche anche per l'attivita' nelle feci e nel sangue. Il modello sviluppato comprende un modello scheletrico

Grouping nanomaterials to predict their potential to induce pulmonary inflammation.

Science.gov (United States)

Braakhuis, Hedwig M; Oomen, Agnes G; Cassee, Flemming R

2016-05-15

The rapidly expanding manufacturing, production and use of nanomaterials have raised concerns for both worker and consumer safety. Various studies have been published in which induction of pulmonary inflammation after inhalation exposure to nanomaterials has been described. Nanomaterials can vary in aspects such as size, shape, charge, crystallinity, chemical composition, and dissolution rate. Currently, efforts are made to increase the knowledge on the characteristics of nanomaterials that can be used to categorise them into hazard groups according to these characteristics. Grouping helps to gather information on nanomaterials in an efficient way with the aim to aid risk assessment. Here, we discuss different ways of grouping nanomaterials for their risk assessment after inhalation. Since the relation between single intrinsic particle characteristics and the severity of pulmonary inflammation is unknown, grouping of nanomaterials by their intrinsic characteristics alone is not sufficient to predict their risk after inhalation. The biokinetics of nanomaterials should be taken into account as that affects the dose present at a target site over time. The parameters determining the kinetic behaviour are not the same as the hazard-determining parameters. Furthermore, characteristics of nanomaterials change in the life-cycle, resulting in human exposure to different forms and doses of these nanomaterials. As information on the biokinetics and in situ characteristics of nanomaterials is essential but often lacking, efforts should be made to include these in testing strategies. Grouping nanomaterials will probably be of the most value to risk assessors when information on intrinsic characteristics, life-cycle, biokinetics and effects are all combined. Copyright © 2015 Elsevier Inc. All rights reserved.

A plant-wide aqueous phase chemistry module describing pH variations and ion speciation/pairing in wastewater treatment process models.

Science.gov (United States)

Flores-Alsina, Xavier; Kazadi Mbamba, Christian; Solon, Kimberly; Vrecko, Darko; Tait, Stephan; Batstone, Damien J; Jeppsson, Ulf; Gernaey, Krist V

2015-11-15

There is a growing interest within the Wastewater Treatment Plant (WWTP) modelling community to correctly describe physico-chemical processes after many years of mainly focusing on biokinetics. Indeed, future modelling needs, such as a plant-wide phosphorus (P) description, require a major, but unavoidable, additional degree of complexity when representing cationic/anionic behaviour in Activated Sludge (AS)/Anaerobic Digestion (AD) systems. In this paper, a plant-wide aqueous phase chemistry module describing pH variations plus ion speciation/pairing is presented and interfaced with industry standard models. The module accounts for extensive consideration of non-ideality, including ion activities instead of molar concentrations and complex ion pairing. The general equilibria are formulated as a set of Differential Algebraic Equations (DAEs) instead of Ordinary Differential Equations (ODEs) in order to reduce the overall stiffness of the system, thereby enhancing simulation speed. Additionally, a multi-dimensional version of the Newton-Raphson algorithm is applied to handle the existing multiple algebraic inter-dependencies. The latter is reinforced with the Simulated Annealing method to increase the robustness of the solver making the system not so dependent of the initial conditions. Simulation results show pH predictions when describing Biological Nutrient Removal (BNR) by the activated sludge models (ASM) 1, 2d and 3 comparing the performance of a nitrogen removal (WWTP1) and a combined nitrogen and phosphorus removal (WWTP2) treatment plant configuration under different anaerobic/anoxic/aerobic conditions. The same framework is implemented in the Benchmark Simulation Model No. 2 (BSM2) version of the Anaerobic Digestion Model No. 1 (ADM1) (WWTP3) as well, predicting pH values at different cationic/anionic loads. In this way, the general applicability/flexibility of the proposed approach is demonstrated, by implementing the aqueous phase chemistry module in some

Lead remediation and changes in human lead exposure: some physiological and biokinetic dimensions.

Science.gov (United States)

Mushak, Paul

2003-02-15

This paper presents a qualitative and quantitative analysis of the various aspects of lead remediation effectiveness with particular reference to human health risk assessment. One of the key elements of lead remediation efforts at such sites as those under the Superfund program deals with populations at elevated exposure and toxicity risk in the proximity of, or at, the site of remediation, especially remediation workers, workers at other tasks on sites that were remediated down to some action level of lead concentration in soils, and groups at risk in nearby communities. A second element has to do with how one measures or models lead exposure changes with special reference to baseline and post-remediation conditions. Various biomarkers of lead exposure can be employed, but their use requires detailed knowledge of what results using each means. The most commonly used approach is measurement of blood lead (Pb-B). Recognized limitations in the use of Pb-B has led to the use of predictive Pb exposure models, which are less vulnerable to the many behavioral, physiological, and environmental parameters that can distort isolated or 'single shot' Pb-B testings. A third aspect covered in this paper presents various physiological factors that affect the methods by which one evaluates Pb remediation effectiveness. Finally, this article offers an integrated look at how lead remediation actions directed at one lead source or pathway affect the total lead exposure picture for human populations at elevated lead exposure and toxicity risk.

Author Details

African Journals Online (AJOL)

Swanepoel, M. Vol 23, No 1:1 (2017) - Articles A comparative overview of exercise and health related professions: Athletic training, clinical exercise physiology and biokinetics. Abstract · Vol 23, No 1:2 (2017) - Articles Relationship between physical activity, body fatness and cardiorespiratory fitness in South African ...

Bio-kinetic energy harvesting using electroactive polymers

Science.gov (United States)

Slade, Jeremiah R.; Bowman, Jeremy; Kornbluh, Roy

2012-06-01

In hybrid vehicles, electric motors are used on each wheel to not only propel the car but also to decelerate the car by acting as generators. In the case of the human body, muscles spend about half of their time acting as a brake, absorbing energy, or doing what is known as negative work. Using dielectric elastomers it is possible to use the "braking" phases of walking to generate power without restricting or fatiguing the Warfighter. Infoscitex and SRI have developed and demonstrated methods for using electroactive polymers (EAPs) to tap into the negative work generated at the knee during the deceleration phase of the human gait cycle and convert it into electrical power that can be used to support wearable information systems, including display and communication technologies. The specific class of EAP that has been selected for these applications is termed dielectric elastomers. Because dielectric elastomers dissipate very little mechanical energy into heat, greater amounts of energy can be converted into electricity than by any other method. The long term vision of this concept is to have EAP energy harvesting cells located in components of the Warfighter ensemble, such as the boot uppers, knee pads and eventually even the clothing itself. By properly locating EAPs at these sites it will be possible to not only harvest power from the negative work phase but to actually reduce the amount of work done by the Warfighter's muscles during this phase, thereby reducing fatigue and minimizing the forces transmitted to the joints.

CFD simulation of fluid dynamic and biokinetic processes within activated sludge reactors under intermittent aeration regime.

Science.gov (United States)

Sánchez, F; Rey, H; Viedma, A; Nicolás-Pérez, F; Kaiser, A S; Martínez, M

2018-08-01

Due to the aeration system, biological reactors are the most energy-consuming facilities of convectional WWTPs. Many biological reactors work under intermittent aeration regime; the optimization of the aeration process (air diffuser layout, air flow rate per diffuser, aeration length …) is necessary to ensure an efficient performance; satisfying the effluent requirements with the minimum energy consumption. This work develops a CFD modelling of an activated sludge reactor (ASR) which works under intermittent aeration regime. The model considers the fluid dynamic and biological processes within the ASR. The biological simulation, which is transient, takes into account the intermittent aeration regime. The CFD modelling is employed for the selection of the aeration system of an ASR. Two different aeration configurations are simulated. The model evaluates the aeration power consumption necessary to satisfy the effluent requirements. An improvement of 2.8% in terms of energy consumption is achieved by modifying the air diffuser layout. An analysis of the influence of the air flow rate per diffuser on the ASR performance is carried out. The results show a reduction of 14.5% in the energy consumption of the aeration system when the air flow rate per diffuser is reduced. The model provides an insight into the aeration inefficiencies produced within ASRs. Copyright © 2018 Elsevier Ltd. All rights reserved.

Development of a New Bio-Kinetic Model for Assessing the Environmental Property of Military Hydraulic Fluids

National Research Council Canada - National Science Library

Rhee, In-Sik

2006-01-01

The U.S. Army Tank-Automotive Research. Development and Engineering Center (TARDEC) is actively developing biodegradation technologies that can be used to minimize waste stream of Petroleum, Oils, and Lubricant...

The IMBA suite: integrated modules for bioassay analysis

Energy Technology Data Exchange (ETDEWEB)

Birchall, A.; Jarvis, N.S.; Peace, M.S.; Riddell, A.E.; Battersby, W.P

1998-07-01

The increasing complexity of models representing the biokinetic behaviour of radionuclides in the body following intake poses problems for people who are required to implement these models. The problem is exacerbated by the current paucity of suitable software. In order to remedy this situation, a collaboration between British Nuclear Fuels, Westlakes Research Institute and the National Radiological Protection Board has started with the aim of producing a suite of modules for estimating intakes and doses from bioassay measurements using the new ICRP models. Each module will have a single purpose (e.g. to calculate respiratory tract deposition) and will interface with other software using data files. The elements to be implemented initially are plutonium, uranium, caesium, iodine and tritium. It is intended to make the software available to other parties under terms yet to be decided. This paper describes the proposed suite of integrated modules for bioassay analysis, IMBA. (author)

United States Transuranium and Uranium Registries

International Nuclear Information System (INIS)

Kathren, R.L.; Filipy, R.E.; Dietert, S.E.

1991-06-01

This report summarizes the primary scientific activities of the United States Transuranium and Uranium Registries for the period October 1, 1989 through September 30, 1990. The Registries are parallel human tissue research programs devoted to the study of the actinide elements in humans. To date there have been 261 autopsy or surgical specimen donations, which include 11 whole bodies. The emphasis of the Registry was directed towards quality improvement and the development of a fully computerized data base that would incorporate not only the results of postmortem radiochemical analysis, but also medical and monitoring information obtained during life. Human subjects reviews were also completed. A three compartment biokinetic model for plutonium distribution is proposed. 2 tabs

The BIDAS: bioassay data analysis software for evaluating radionuclide intake and dose

International Nuclear Information System (INIS)

Lee, Tae Young; Lee, Jong Il; Chang, Si Young

2003-01-01

The BIDAS (BIoassay Data Analysis Software) computer code was developed for the interpretation of bioassay measurements in terms of the intake and dose using the International Commission on Radiological Protection's(ICRP's) currently recommended respiratory tract, GI-tract and biokinetic models to describe the behavior of the radioactive materials within the body. The code consists of a data base module to the manage bioassay data, a data base module containing the predicted bioassay quantities of each radionuclide, and a computational module to the estimate radionuclide intake and dose from either an acute or a chronic exposure based on the measured bioassay quantities. This paper describes the features of the code as well as the results of the BIDAS validation

Absorbed radiation doses in women undergone to PET-CT exams for cancer diagnosis

International Nuclear Information System (INIS)

Santana, Priscila do Carmo; Bernardes, Felipe Dias; Mamede, Marcelo; Oliveira, Paulo Marcio Campos de; Silva, Teogenes Augusto da; Mourao FIlho, Arnaldo Prata

2014-01-01

The absorbed dose in several organs and the effective dose in patients submitted to PET-CT exams with the radiopharmaceutical 18 F-FDG were assessed. The ICRP-106 biokinetic model and thermoluminescent detectors in a anthropomorphic phantom were used. The use of the PET-CT image acquisition protocol, with the CT protocol for anatomical mapping, showed that 60% of effective dose was from the radiotracer administration, being the effective dose values for a female patient of (5.80 ± 1.57) mSv. In conclusion, patient doses can be reduced by using appropriate imaging acquisition in 18 F-FDG PET-CT examinations and promoting the compliance with the radiation protection principles. (author)

Management of internal contamination accidents

International Nuclear Information System (INIS)

Lipsztein, J.L.; Melo, D.R.

1997-01-01

This paper concerns with the techniques for intakes assessment which depend on the mode and level of intake, the type of energy of the radiation emitted, the biokinetic of the contaminant, and the sensitivity and availability of measurement facilities. In vivo and in vitro techniques are used to quantify internal contaminations

Contribution to the study of external contamination by radioactive products: skin contamination by radioactive cobalt in soluble form and decontamination

International Nuclear Information System (INIS)

Tymen, H.

2002-12-01

The aim of this work was to characterize the behavior of the radioactive cobalt isotopes, which are present in reactor coolant systems of a pressurized water reactor (PWR), in the case of occupational skin exposure, and to study different therapies. Our experimental approach stems from standardized methods in skin pharmacology. In a first step, a physico-chemical study of a primary coolant water was carried out to characterize the soluble fraction of radio-cobalt and its skin affinity. The second step consisted in quantifying the diffusion through the skin, in vivo and in vitro in rats, and in vitro in human. Parallel experiments were carried out to study biokinetics of cobalt in rats, after intravenous, intramuscular and subcutaneous injection. Whatever the route of administration, cobalt diffuses easily in the organism. On the contrary, its skin absorption is very limited. In a fourth step, the influence of the skin injuries on absorption was estimated in vivo on rat skin. Several skin models were developed to standardize different injuries: excoriation, heat burns (convection, conduction) and chemical burns (acid or alkaline). Biokinetics study over 24 hours and histological study have shown a relation between skin absorption and stratum corneum alteration. In the latest step of this work, we compared the efficacy of various decontaminating agents administered under different galenic forms. Per (3, 6- anhydro, 2-O-carboxy-methyl)-α-cyclo-dextrin exhibited a significant efficacy for cobalt decontamination of skin. This macromolecule was tested in aqueous solution, in agarose gel and loaded on 'functionalized' fibers intended for development of new decontaminating tissues. (author)

IMBA professional plus: internal dosimetry made simple

International Nuclear Information System (INIS)

Birchall, A.; Puncher, M.; Marsh, J.W.; Davis, K.; Bailey, M.R.; Peach, A.; James, A.C.; Jarvis, N.S.

2005-01-01

Full text: During 1997-1999, NRPB, in collaboration with British Nuclear Fuels plc (BNFL), and Westlakes Research Institute, produced IMBA (Integrated Modules for Bioassay Analysis), a suite of software modules that implement the current ICRP biokinetic and dosimetric models for estimation of intakes and doses. This was partly in response to new UK regulations that implemented the 1996 Euratom Directive, and partly in recognition of the advantages of a unified approach to estimating intakes and doses from bioassay measurements. The IMBA modules have gone through extensive quality assurance, and are now used for routine formal dose assessment by Approved Dosimetry Services throughout the UK. Over the past 5 years, NRPB has developed the IMBA modules further. In addition, several projects, sponsored by organizations both in the USA and in Canada, resulted in the development of customized user friendly interfaces (IMBA Expert TM 'editions'). These enable their users not only to use the standard ICRP models, but also to change many of the parameter values from their defaults, and also to apply sophisticated data handling techniques to internal dose calculations. These include fitting multiple data using the maximum likelihood method, multiple chronic and acute intakes, and multiple data types (urine, faeces, whole body etc.) simultaneously. These interfaces were improved further, as a result of user feedback, and a general off-the-shelf product, IMBA Professional, was developed and made available in January 2004. Following the success of IMBA Professional, a new and improved product IMBA Professional Plus is planned to be released in 2005. The new product is more powerful than its predecessor, six times faster, cheaper, and fully backward compatible with previous versions. It is envisaged that this package will continue to be developed as improved methods of analysis and biokinetic models become available. The aim of this paper is to describe the current capabilities

External costs of atmospheric Pb emissions: valuation of neurotoxic impacts due to inhalation

Directory of Open Access Journals (Sweden)

Frohn Lise

2010-02-01

Full Text Available Abstract Background The Impact Pathway Approach (IPA is an innovative methodology to establish links between emissions, related impacts and monetary estimates. Only few attempts have so far been presented regarding emissions of metals; in this study the external costs of airborne lead (Pb emissions are assessed using the IPA. Exposure to Pb is known to provoke impacts especially on children's cognition. As cognitive abilities (measured as IQ, intelligence quotient are known to have implications for lifetime income, a pathway can be established leading from figures for Pb emissions to the implied loss in earnings, and on this basis damage costs per unit of Pb emission can be assessed. Methods Different types of models are here linked. It is relatively straightforward to establish the relationship between Pb emissions and consequent increase in air-Pb concentration, by means of a Gaussian plume dispersion model (OML. The exposed population can then be modelled by linking the OML-output to population data nested in geo-referenced grid cells. Less straightforward is to establish the relationship between exposure to air-Pb concentrations and the resulting blood-Pb concentration. Here an Age-Dependent Biokinetic Model (ADBM for Pb is applied. On basis of previous research which established links between increases in blood-Pb concentrations during childhood and resulting IQ-loss we arrive at our results. Results External costs of Pb airborne emissions, even at low doses, in our site are in the range of 41-83 €/kg emitted Pb, depending on the considered meteorological year. This estimate applies only to the initial effects of air-Pb, as our study does not address the effects due to the Pb environmental-accumulation and to the subsequent Pb re-exposure. These are likely to be between one and two orders of magnitude higher. Conclusions Biokinetic modelling is a novel tool not previously included when applying the IPA to explore impacts of Pb emissions

Uranium levels in the diet of São Paulo City residents.

Science.gov (United States)

Garcia, F; Barioni, A; Arruda-Neto, J D T; Deppman, A; Milian, F; Mesa, J; Rodriguez, O

2006-07-01

Natural levels of uranium in the diet of São Paulo City residents were studied, and radionuclide concentrations were measured by the fission track method on samples of typical adult food items. This information was used to evaluate the daily intake of uranium in individuals living in São Paulo City which is, according to our findings, around 0.97 microg U/day. Using the ICRP Uranium-model, we estimated the uranium accumulation and committed doses in some tissues and organs, as function of time. We compared the output of the ICRP uranium biokinetic model, tailored for the conditions prevailing in São Paulo, with experimental data from other localities. Such comparison was possible by means of a simple method we developed, which allows normalization among experimental results from different regions where distinct values of chronic daily intake are observed.

The contribution of chemical speciation to internal dosimetry

International Nuclear Information System (INIS)

Paquet, F.; Frelon, S.; Cote, G.; Madic, C.

2003-01-01

Speciation studies refer to the distribution of species in a particular sample or matrix. These studies are necessary to improve the description, understanding and prediction of trace element kinetics and toxicity. In the case of internal contamination with radionuclides, speciation studies could help to improve both the biokinetic and dosimetric models for radionuclides. There are different methods to approach the speciation of radionuclides in a biological system, depending on the degree of accuracy needed and the level of uncertainties accepted. Among them, computer modelling and experimental determination are complementary approaches. This paper describes what is known about speciation of actinides in blood, GI tract, liver and skeleton and of their consequences in terms of internal dosimetry. The conclusion is that such studies provide very valuable data and should be targeted in the future on some specific tissues and biomolecules. (author)

The relationship of overweight and obesity to the motor performance ...

African Journals Online (AJOL)

2011-11-02

Nov 2, 2011 ... School of Biokinetics, Recreation and Sport Science, North-West University, Potchefstroom Campus. Du Toit D, PhD .... the eyes closed on a balance beam. This showed a negative correlation with a small practical significance with BMI and body fat percentage, and copying a square, as well as dribbling a.

Root uptake of uranium by a higher plant model (Phaseolus vulgaris) bioavailability from soil solution

International Nuclear Information System (INIS)

Laroche, L.; Henner, P.; Camilleri, V.; Garnier-Laplace, J.

2004-01-01

Uranium behaviour in soils is controlled by actions and interactions between physicochemical and biological processes that also determine its bioavailability. In soil solution, uranium(+VI) aqueous speciation undergoes tremendous changes mainly depending on pH, carbonates, phosphates and organic matter. In a first approach to identify bioavailable species of U to plants, cultures were performed using hydroponics, to allow an easy control of the composition of the exposure media. The latter, here an artificial soil solution, was designed to control the uranium species in solution. The geochemical speciation code JCHESS using a database compiled from the OECD/NEA thermochemical database project and verified was used to perform the solution speciation calculations. On this theoretical basis, three domains were defined for short-duration well-defined laboratory experiments in simplified conditions: pH 4.9, 5.8 and 7 where predicted dominant species are uranyl ions, hydroxyl complexes and carbonates respectively. For these domains, biokinetics and characterization of transmembrane transport according to a classical Michaelis Menten approach were investigated. The Free Ion Model (or its derived Biotic Ligand Model) was tested to determine if U uptake is governed by the free uranyl species or if other metal complexes can be assimilated. The effect of different variables on root assimilation efficiency and phyto-toxicity was explored: presence of ligands such as phosphates or carbonates and competitive ions such as Ca 2+ at the 3 pH. According to previous experiments, uranium was principally located in roots whatever the pH and no difference in uranium uptake was evidenced between the main growth stages of the plant. Within the 3 studied chemical domains, results from short-term kinetics evidenced a linear correlation between total uranium concentration in bean roots and that in exposure media, suggesting that total uranium in soil solution could be a good predictor for

Root uptake of uranium by a higher plant model (Phaseolus vulgaris) bioavailability from soil solution

Energy Technology Data Exchange (ETDEWEB)

Laroche, L.; Henner, P.; Camilleri, V.; Garnier-Laplace, J. [CEA Cadarache (DEI/SECRE/LRE), Laboratory of Radioecology and Ecotoxicology, Institute for Radioprotection and Nuclear Safety, 13 - Saint-Paul-lez-Durance (France)

2004-07-01

Uranium behaviour in soils is controlled by actions and interactions between physicochemical and biological processes that also determine its bioavailability. In soil solution, uranium(+VI) aqueous speciation undergoes tremendous changes mainly depending on pH, carbonates, phosphates and organic matter. In a first approach to identify bioavailable species of U to plants, cultures were performed using hydroponics, to allow an easy control of the composition of the exposure media. The latter, here an artificial soil solution, was designed to control the uranium species in solution. The geochemical speciation code JCHESS using a database compiled from the OECD/NEA thermochemical database project and verified was used to perform the solution speciation calculations. On this theoretical basis, three domains were defined for short-duration well-defined laboratory experiments in simplified conditions: pH 4.9, 5.8 and 7 where predicted dominant species are uranyl ions, hydroxyl complexes and carbonates respectively. For these domains, biokinetics and characterization of transmembrane transport according to a classical Michaelis Menten approach were investigated. The Free Ion Model (or its derived Biotic Ligand Model) was tested to determine if U uptake is governed by the free uranyl species or if other metal complexes can be assimilated. The effect of different variables on root assimilation efficiency and phyto-toxicity was explored: presence of ligands such as phosphates or carbonates and competitive ions such as Ca{sup 2+} at the 3 pH. According to previous experiments, uranium was principally located in roots whatever the pH and no difference in uranium uptake was evidenced between the main growth stages of the plant. Within the 3 studied chemical domains, results from short-term kinetics evidenced a linear correlation between total uranium concentration in bean roots and that in exposure media, suggesting that total uranium in soil solution could be a good predictor

What is New in Internal Dosimetry and Monitoring?

International Nuclear Information System (INIS)

Henrichs, K.; Nosske, D.

2006-01-01

This file is divided in two parts:the first one concerns the progress in internal dosimetry. This part gives an overview on new model developments by ICRP, the series of age dependent doses for members of the public was continued by biokinetic and dosimetric models for the embryo and foetus due to activity intake by the mother (ICRP,2001) and for the infant via consumption of mother's milk after activity intake by the mother (ICRP, 2004). In both publications dose coefficients for the embryo and foetus as well the infant were given for various intake scenarios by mother. The present model development work of ICRP is a revision of Publications 30, 54, 68, and 78 based on the new human Alimentary tract model (H.A.T.M.) of ICRP (ICRP, 2006), a revision of absorption parameters for the human respiratory tract model (ICRP, 1994a), new systemic models as well as new dosimetric parameters derived with new Voxel models for the reference male and female adult. The second part concerns the progress in workers monitoring for radionuclide intake. The initiatives to improve the situation are the guidelines published by the International Atomic Energy Agency (2004), giving guidance for the assessment of occupational exposures due to intakes of radionuclides, research project funded by the European Commission: the objective of O.M.I.N.E.X. was the improvement of monitoring programmes, taking into account the uncertainties of biokinetic models and data, the programme I.D.E.A. tried to improve measuring techniques and I.D.E.A.S derives rules for the evaluation of measured activity values in terms of exposure. Standardization projects by the International Standardization Organization I.S.O.: I.S.O. (2001) published a standard defining the requirements for bioassay laboratories, which will soon followed by a second part giving the rationale behind these rules., presently the final version (I.S.O. 2005) of a standard is circulating among the I.S.O. member states which guidance on the

Absorbed Doses to Patients in Nuclear Medicine; Doskatalogen foer nukleaermedicin

Energy Technology Data Exchange (ETDEWEB)

Leide-Svegborn, Sigrid; Mattsson, Soeren; Nosslin, Bertil [Universitetssjukhuset MAS, Malmoe (Sweden). Avd. foer radiofysik; Johansson, Lennart [Norrlands Universitetssjukhus, Umeaa (Sweden). Avd. foer radiofysik

2004-09-01

The work with a Swedish catalogue of radiation absorbed doses to patients undergoing nuclear medicine investigations has continued. After the previous report in 1999, biokinetic data and dose estimates (mean absorbed dose to various organs and tissues and effective dose) have been produced for a number of substances: {sup 11}C- acetate, {sup 11}C- methionine, {sup 18}F-DOPA, whole antibody labelled with either {sup 99m}Tc, {sup 111}In, {sup 123}I or {sup 131}I, fragment of antibody, F(ab'){sub 2} labelled with either {sup 99m}Tc, {sup 111}In, {sup 123}I or {sup 131}I and fragment of antibody, Fab' labelled with either {sup 99m}Tc, {sup 111}In, {sup 123}I or {sup 131}I. The absorbed dose estimates for these substances have been made from published biokinetic information. For other substances of interest, e.g. {sup 14}C-urea (children age 3-6 years), {sup 14}C-glycocholic acid, {sup 14}C-xylose and {sup 14}C-triolein, sufficient literature data have not been available. Therefore, a large number of measurements on patients and volunteers have been carried out, in order to determine the biokinetics and dosimetry for these substances. Samples of breast milk from 50 mothers, who had been subject to nuclear medicine investigations, have been collected at various times after administration of the radiopharmaceutical to the mother. The activity concentration in the breast milk samples has been measured. The absorbed dose to various organs and tissues and the effective dose to the child who ingests the milk have been determined for 17 different radiopharmaceuticals. Based on these results revised recommendations for interruption of breast-feeding after nuclear medicine investigations are suggested.

Mathematical model for carbon dioxide evolution from the thermophilic composting of synthetic food wastes made of dog food

International Nuclear Information System (INIS)

Chang, J.I.; Tsai, J.J.; Wu, K.H.

2005-01-01

The impacts of the aeration and the agitation on the composting process of synthetic food wastes made of dog food were studied in a laboratory-scale reactor. Two major peaks of CO 2 evolution rate were observed. Each peak represented an independent stage of composting associated with the activities of thermophilic bacteria. CO 2 evolutions known to correlate well with microbial activities and reactor temperatures were fitted successfully to a modified Gompertz equation, which incorporated three biokinetic parameters, namely, CO 2 evolution potential, specific CO 2 evolution rate, and lag phase time. No parameters that describe the impact of operating variables are involved. The model is only valid for the specified experimental conditions and may look different with others. The effects of operating parameters such as aeration and agitation were studied statistically with multivariate regression technique. Contour plots were constructed using regression equations for the examination of the dependence of CO 2 evolution potentials on aeration and agitation. In the first stage, a maximum CO 2 evolution potential was found when the aeration rate and the agitation parameter were set at 1.75 l/kg solids-min and 0.35, respectively. In the second stage, a maximum existed when the aeration rate and the agitation parameter were set at 1.8 l/kg solids-min and 0.5, respectively. The methods presented here can also be applied for the optimization of large-scale composting facilities that are operated differently and take longer time

Plutonium

International Nuclear Information System (INIS)

Koelzer, W.

1989-03-01

This report contains with regard to 'plutonium' statements on chemistry, occurrence and reactions in the environment, handling procedures in the nuclear fuel cycle, radiation protection methods, biokinetics, toxicology and medical treatment to make available reliable data for the public discussion on plutonium especially its use in nuclear power plants and its radiological assessment. (orig.) [de

A saturable repair model for radionuclide therapy using low LET radiation emitters

International Nuclear Information System (INIS)

Calderon, Carlos F.; Joaquin Gonzalez; Guido Martin

2004-01-01

Purpose: In conventional radiotherapy doses of about 60Gy are necessary to achieve the tumor control or eradication. For systemic applications in radionuclide radiotherapy (RT) 0.1-0.5cGy/min and total dose 15-20 Gy could be reached with effective irradiation times of few days. The dose rate in tumor change exponentially as a time function where an uptake phase well differentiated from an elimination phase-will- appear both determined by the effective uptake and elimination times respectively. The biological response in RT will be determined not only by the total dose, but also by initial dose rate, the length of irradiation time (effective half-life) and biological factors, like radiosensitivity, repair and doubling times. Most quantitative models of radiation action on cells make the assumption that cell repair mechanisms are relevant in the response and it proceed in a dose-dependent way. The cell proliferation will influence too the response when the overall irradiation is comparable or greater than cell population doubling time. Many proposal had been made to apply radiobiological model for the prediction of the treatment response in RN. Saturable repair models are able, in principle, to explain the usual data base of radiobiological phenomena including which where other biophysical model does not work good. It is presented here an analytical expression to calculate the survival fraction in a cell population after irradiation based on a saturable repair radiobiological model proposed by Sanchez-Reyes [Sanchez-Reyes A. Radiact. Res., 1992;130:139-147] as function of radiobiological and biokinetics parameters which could be used in RN. The original radiobiological model consider a cell population where the DNA repair mechanisms are saturable and it could be affected by radiation action. The contribution of cell proliferation were considered keeping in mind that cell population grow up exponentially at constant rate. The dose rate was considered uniformly

Comparison and modification of Pu-239 kinetics in young and adult rats

International Nuclear Information System (INIS)

Volf, V.; Gamer, A.; Laengle, U.

1987-01-01

It is obvious that the biokinetics of bone-seeking radionuclides are influenced by skeletal growth and remodelling, the rate of which in general decreases with increasing age. For plutonium, Mahlum and Sikov (1974) observed that rats injected with Pu-239 as weanlings retained a lower percentage in the liver and more in the bones than the animals injected as adults. However, skeletal Pu-239 was diluted more rapidly in the young rats because of intensive new bone formation and this led to a more pronounced reduction in the accumulation of radiation dose than was the case in adult animals. The aim of the present experiments was to study: a) The age effect on Pu-239 biokinetics in adult rates as influenced by the sex of the animals. b) Early retention and distribution of Pu-239 in the bones of young and adult rats injected with an optimal osteosarcomogenic dose. c) The effectiveness of a delayed prolonged administration of Zn-DTPA in drinking water for the mobilization of injected Pu-239 in rats of various age. 3 refs.; 5 figs.; 1 table

Polonium-210 and other radionuclides in terrestrial, freshwater and brackish environments Results from the NKS project GAPRAD (Filling knowledge gaps in radiation protection methodologies for non-human biota)

Energy Technology Data Exchange (ETDEWEB)

Gjelsvik, R; Brown, J; Holm, E; Roos, P; Saxen, R; Outola, I

2012-01-15

The background and rationale to filling knowledge gaps in radiation protection methodologies for biota are presented. Concentrations of Po-210 and Pb-210 are reported for biota sampled in Dovrefjell, Norway and selected lake and brackish ecosystems in Finland. Furthermore, details in relation to Po-210 uptake and biokinetics in humans based on experimental studies are recounted. (Author)

Polonium-210 and other radionuclides in terrestrial, freshwater and brackish environments Results from the NKS project GAPRAD (Filling knowledge gaps in radiation protection methodologies for non-human biota)

International Nuclear Information System (INIS)

Gjelsvik, R.; Brown, J.; Holm, E.; Roos, P.; Saxen, R.; Outola, I.

2012-01-01

The background and rationale to filling knowledge gaps in radiation protection methodologies for biota are presented. Concentrations of Po-210 and Pb-210 are reported for biota sampled in Dovrefjell, Norway and selected lake and brackish ecosystems in Finland. Furthermore, details in relation to Po-210 uptake and biokinetics in humans based on experimental studies are recounted. (Author)

Anoxic Activated Sludge Monitoring with Combined Nitrate and Titrimetric Measurements

DEFF Research Database (Denmark)

Petersen, B.; Gernaey, Krist; Vanrolleghem, P.A.

2002-01-01

was with the carbon source in excess, since excess nitrate provoked nitrite build-up thereby complicating the data interpretation. A conceptual model could quantitatively describe the experimental observations and thus link the experimentally measured proton production with the consumption of electron acceptor......An experimental procedure for anoxic activated sludge monitoring with combined nitrate and titrimetric measurements is proposed and evaluated successfully with two known carbon sources, (-)acetate and dextrose. For nitrate measurements an ion-selective nitrate electrode is applied to allow...... for frequent measurements, and thereby the possibility for detailed determination of the denitrification biokinetics. An internal nitrate electrode calibration is implemented in the experiments to avoid the often-encountered electrode drift problem. It was observed that the best experimental design...

Proceedings of the Fetal Dosimetry Workshop held in Chalk River, ON (Canada), 25-26 June 1991

International Nuclear Information System (INIS)

Lamothe, E.S.

1992-06-01

It is important to ensure adequate protection of the developing embryo or fetus in situations where the parent, usually the mother, is potentially exposed to radionuclides. An embryo or fetus can be exposed to ionizing radiation by external or internal sources. The dose from external sources can be assessed relatively easily. There is considerable uncertainty as to what the fetal doses are following maternal intakes, and whether low doses of radiation to the fetus cause childhood cancer. This workshop was held to help address these issues. Discussions centered in particular on the biokinetics of the distribution and retention of radionuclides in the fetus and newborn, effects of incorporated radionuclides in the embryo or fetus, metabolic and dosimetric models, and radioprotection considerations. Eleven papers were presented

Estimation of foetal brain dose from I-131 in the foetal thyroid

International Nuclear Information System (INIS)

O'Hare, N.J.; Murphy, D.; Malone, J.F.; Gilligan, P.

1997-01-01

The ingestion of I-131 by pregnant women can have consequences for the developing foetus, in particular brain function. As the foetal thyroid accumulates iodine from the twelfth week of gestation onwards, the determination of foetal brain dose resulting from such I-131 accumulation is essential. Normal dosimetric methods fail to treat the case of the foetus. Using an approximation method based on the MIRD approach, a foetal dose estimation scheme is developed to allow the determination of foetal brain dose from foetal thyroid irradiation. Dose values are obtained for the foetus based on the maternal intake of I-131. It was found that the choice of biokinetic model for the mother/foetus has a large impact on the determined dose estimate. (author)

Whole body MR-PET: a new internal dosimetry method for radiation transport calculation from biokinetic model data

International Nuclear Information System (INIS)

Nunes, Ana; Alves, Francisco; Patrício, Miguel

2014-01-01

In order to ensure the safe usage of new radiopharmaceuticals in Positron Emission Tomography (PET), it is necessary to quantify the doses delivered to the organs and tissues within the patients’ bodies. A framework that allows estimating the dose delivered by PET has been established by the MIRD Committee [1, 2] and ICRP []. Although this covers the most important terms and concepts in Internal Radiation Dosimetry (IRD), it does not provide a detailed guide to assist in the development of a full dosimetric study. We discuss the development, implementation, assessment and validation of an accurate method for IRD studies of PET radiotracers.

Biokinetics of 237Np in mussels and shrimp

International Nuclear Information System (INIS)

Guary, J.C.; Fowler, S.W.

1977-01-01

Neptunium-237 kinetics were studied in marine shrimp and mussels using a thick source alpha counting technique. Bioaccumulation of 237 Np from water was relatively slow in both species, reaching whole body concentration factors of only 15 to 20 after three months. Surface adsorption was implicated in the initial uptake. Both uptake and loss of the radioisotope were not significantly affected by temperature; this may be a reflection of the physical nature of the uptake. By virtue of the large amounts of accumulated 237 Np associated with the exoskeleton of shrimp, molting will play an important role in the biogeochemical cycling of this transuranic in the marine environment. Rapid growth of organisms like mussels acts to reduce the 237 Np concentration in tissues during a period of decontamination

Biokinetic studies on 14C-chitosan in rats

International Nuclear Information System (INIS)

Jia Minghong; Nishimura, Y.; Watanabe, Y.; Yukawa, M.

1998-05-01

The absorption and the basic metabolism of chitosan in rats are investigated. The results indicated that 14 C-chitosan from gastrointestinal tract was absorbed, metabolized and excreted quickly without re-bioavailability. The radioactive compounds perhaps with specifically chemical forms in serum, liver and the contents of small intestines were separated on GPC column and measured by radioactivity counting. A big pile of peaks with the retention volume almost same as that of standard 14 C-chitosan and another sharp one with the retention volume in the range of higher molecular weight same as that of BSA were discovered in analysis respectively for contents of intestine and serum or liver. The sharp peak would disappear if the proteins contained in the serum or liver were removed. In addition, and interesting tail peak, followed with the pile ones and eluted with the retention volume of lower molecular weight range same as that of chitooligosaccharides was also found in each of the 3 samples, ignoring the protein removal or not. These results suggested that most of 14 C-chitosan was not to be digested in intestine. On the other hand, a small amount of 14 C-chitosan was likely to be absorbed directly or after degraded to small molecular compounds into blood, liver and other tissues, and then connected with the proteins. Perhaps it is these trace materials that were playing important roles in reduction of the bioavailability of radiostrontium in rats

Micro-dosing for early biokinetic studies in humans

International Nuclear Information System (INIS)

Stenstroem, K.; Sydoff, M.; Mattsson, S.

2010-01-01

Micro-dosing is a new concept in drug development that-if implemented in the pharmaceutical industry-would mean that new drugs can be tested earlier in humans than done today. The human micro-dosing concept-or 'Phase 0'-may offer improved candidate selection, reduced failure rates in the drug development line and a reduction in the use of laboratory animals in early drug development, factors which will help to speed up drug development and also reduce the costs. Micro-dosing utilises sub-pharmacological amounts of the substance to open opportunities for early studies in man. Three technologies are used for micro-dosing: accelerator mass spectrometry (AMS), positron emission tomography and liquid chromatography-tandem mass spectrometry. This paper focuses on the principle of AMS and discusses the current status of micro-dosing with AMS. (authors)

Doses from radiation exposure

CERN Document Server

Menzel, H G

2012-01-01

Practical implementation of the International Commission on Radiological Protection's (ICRP) system of protection requires the availability of appropriate methods and data. The work of Committee 2 is concerned with the development of reference data and methods for the assessment of internal and external radiation exposure of workers and members of the public. This involves the development of reference biokinetic and dosimetric models, reference anatomical models of the human body, and reference anatomical and physiological data. Following ICRP's 2007 Recommendations, Committee 2 has focused on the provision of new reference dose coefficients for external and internal exposure. As well as specifying changes to the radiation and tissue weighting factors used in the calculation of protection quantities, the 2007 Recommendations introduced the use of reference anatomical phantoms based on medical imaging data, requiring explicit sex averaging of male and female organ-equivalent doses in the calculation of effecti...

Determination of Lung-to-Blood Absorption Rates for Lead and Bismuth which are Appropriate for Radon Progeny

International Nuclear Information System (INIS)

Marsh, J.W.; Birchall, A.

1999-01-01

The ICRP Publication 66 Human Respiratory Tract Model (HRTM) treats clearance as a competitive process between absorption into blood and particle transport to the gastrointestinal tract and lymphatics. The ICRP recommends default absorption rates for lead and bismuth in ICRP Publication 71 but states that the values are not appropriate for short-lived radon progeny. This paper describes an evaluation of published data from volunteer experiments to estimate the absorption half-times of lead and bismuth that are appropriate for short-lived radon progeny. The absorption half-time for lead was determined to be 10±2 h, based on 212 Pb lung and blood retention data from several studies. The absorption half-time for bismuth was estimated to be about 13 h, based on 212 Bi urinary excretion data from one experiment and the ICRP biokinetic model for bismuth as a decay product of lead. (author)

Identification of lead sources in residential environments: Sydney Australia

International Nuclear Information System (INIS)

Laidlaw, M.A.S.; Zahran, S.; Pingitore, N.; Clague, J.; Devlin, G.; Taylor, M.P.

2014-01-01

Interior and exterior dust, soil and paint were analysed at five brick urban Sydney homes over 15 months to evaluate temporal variations and discriminate sources of lead (Pb) exposure. Exterior dust gauge Pb loading rates (μg/m 2 /28 days), interior vacuum dust Pb concentrations (mg/kg) and interior petri-dish Pb loading rates (μg/m 2 /28 days), were correlated positively with soil Pb concentrations. Exterior dust gauge Pb loading rates and interior vacuum dust Pb concentrations peaked in the summer. Lead isotope and Pb speciation (XAS) were analysed in soil and vacuum dust samples from three of the five houses that had elevated Pb concentrations. Results show that the source of interior dust lead was primarily from soil in two of the three houses and from soil and Pb paint in the third home. IEUBK child blood Pb modelling predicts that children's blood Pb levels could exceed 5 μg/dL in two of the five houses. -- Highlights: • Exterior Pb loading and interior Pb dust loading and concentrations correlate with soil Pb. • Exterior dust gauge Pb loading rates and interior vacuum dust Pb concentrations peak in the summer. • Interior dust lead came from soil in two of the three houses and from soil and Pb paint in the third home. • Modelling predicts that children's blood Pb levels could exceed 5 μg/dL in two of the five houses. -- Interior and exterior dust, soil and paint were analysed at five brick urban Sydney homes over 15 months to evaluate temporal variations and discriminate sources of lead (Pb) exposure

In vitro and in vivo approaches for the measurement of oral bioavailability of lead (Pb) in contaminated soils: A review

Energy Technology Data Exchange (ETDEWEB)

Zia, Munir Hussain, E-mail: MunirZia@gmail.com [Technical Services Department, Fauji Fertilizer Company Limited, Lahore (Pakistan); USDA-ARS, Environmental Management and By-products Utilization Laboratory, Bldg. 007, BARC-West, Beltsville, MD 20705-2350 (United States); Codling, Eton E. [USDA-ARS, Environmental Management and By-products Utilization Laboratory, Bldg. 007, BARC-West, Beltsville, MD 20705-2350 (United States); Scheckel, Kirk G. [US-Environmental Protection Agency, National Risk Management Research Laboratory Land Remediation and Pollution Control Division, 5995 Center Hill Avenue, Cincinnati, OH 45224-1702 (United States); Chaney, Rufus L. [USDA-ARS, Environmental Management and By-products Utilization Laboratory, Bldg. 007, BARC-West, Beltsville, MD 20705-2350 (United States)

2011-10-15

We reviewed the published evidence of lead (Pb) contamination of urban soils, soil Pb risk to children through hand-to-mouth activity, reduction of soil Pb bioavailability due to soil amendments, and methods to assess bioaccessibility which correlate with bioavailability of soil Pb. Feeding tests have shown that urban soils may have much lower Pb bioavailability than previously assumed. Hence bioavailability of soil Pb is the important measure for protection of public health, not total soil Pb. Chemical extraction tests (Pb bioaccessibility) have been developed which are well correlated with the results of bioavailability tests; application of these tests can save money and time compared with feeding tests. Recent findings have revealed that fractional bioaccessibility (bioaccessible compared to total) of Pb in urban soils is only 5-10% of total soil Pb, far lower than the 60% as bioavailable as food-Pb presumed by U.S.-EPA (30% absolute bioavailability used in IEUBK model). - Highlights: > Among direct exposure pathways for Pb in urban environments, inadvertent ingestion of soil is considered the major concern. > The concentration of lead in house dusts is significantly related to that in garden soil, and is highest at older homes. > In modeling risks from diet/water/soil Pb, US-EPA presumes that soil-Pb is 60% as bioavailable as other dietary Pb. > Joplin study proved that RBALP method seriously underestimated the ability of phosphate treatments to reduce soil Pb bioavailability. > Zia et al. method has revealed that urban soils have only 5-10% bioaccessible Pb of total Pb level. - Improved risk evaluation and recommendations for Pb contaminated soils should be based on bioavailability-correlated bioaccessible soil Pb rather than total soil Pb.

Adaptation of the ICRP models for the Techa River populations to estimate in utero and postnatal haemopoietic tissue doses from ingested strontium isotopes

International Nuclear Information System (INIS)

Shagina, Natalia; Tolstykh, Evgenia; Degteva, Marina; Fell, Tim; Harrison, John

2008-01-01

Full text: Reliable estimation of tissue doses for exposed individuals is very important in epidemiological studies. Long-term cohort studies of the Techa River populations exposed in the early 1950s due to releases of liquid radioactive wastes from the Mayak plutonium production facility (Southern Urals, Russia) are unique in allowing the quantification of risks from low-level chronic exposure of the general population and providing information on risks for persons exposed in utero. Strontium isotopes were the most important contributors to haemopoietic tissue doses for people living in the riverside settlements. Large-scale monitoring of the exposed population has provided a comprehensive database, including post mortem and in vivo measurements of 90 Sr in bones and whole body, for use in the estimation of doses. The International Commission on Radiological Protection (ICRP) has published biokinetic and dosimetric models for the calculation of doses to members of the public, including doses from in utero exposures and from intakes with breast milk. However, the ICRP models as applied to Sr required modification to provide best estimates of doses to Techa River residents. Adaptations were made to the ICRP model for Sr in children and adults to take account of population-specific features relating to bone mineral turnover and to model age and gender differences in strontium retention. Refinements in the ICRP model for Sr uptake and retention in the fetus were made to improve the treatment of discrimination against Sr, relative to Ca, in transfer from maternal to foetal blood and to take account of population-specific data on the calcium content of the maternal and fetal skeleton. Modification of the ICRP model for Sr transfer in breast-milk included adaptations relating to changes in maternal mineral metabolism during lactation and consideration of population-specific features of breast feeding in the rural population. The improved models were successfully

Radiolabeled monoclonal antibodies. Development of a new method to remove circulating activity - diagnostic applications and implications for therapy

International Nuclear Information System (INIS)

Norrgren, K.

1993-04-01

The aim of this thesis was to develop and investigate the usefulness of extracorporeal immunoadsorption (ECIA) to remove circulating activity after the localization of radiolabeled monoclonal antibodies to tumors. A compartment model, based on the biokinetics of 125 I-labeled antibodies 96.5 was developed to estimate the effect of ECIA on the tumor-to-normal tissue ratios. ECIA was simulated at different times after injection of the antibodies and the calculations showed an increased diagnostic ratio for several hours after the ECIA procedure, and that an enhancement of the therapeutic ratio was possible. These results led to the development of animal models where the ECIA could be evaluated and the biokinetic behaviour of different radiolabeled monoclonal antibodies investigated with and without the application of ECIA. A general ECIA method, based on biotinylated antibodies and an avidin agarose column as adsorbent, was developed. Studies in tumor bearing nude rats showed that ECIA enhanced of the tumor-to-normal tissue activity ratios by a factor of 4 for the liver, kidneys and bone marrow. For the L6 antibody, the image contrast of tumors localized in one kidney of the rats, was increased from 1.1 to 1.6. A software anthropomorphic phantom was used in Monte Carlo simulations of clinically realistic scintillation camera image acquisition. The effect of ECIA on the contrast enhancement and on the detectability of simulated tumors located centrally in the liver was studied. The contrast increased linearly with an increasing tumor/liver ratio. The contrast was higher for SPECT than for planar images and a contrast of 1.15 required a tumor/liver activity ratio of 1.9 for SPECT and 4.5 for planar images. ECIA in combination with SPECT imaging of radiolabeled antibodies has a great potential in increasing the detectability of tumors. These studies have shown the possibility with ECIA to increase the contrast in radioimmunoimaging and to enhance the therapeutic ratio

Radiation absorbed dose from medically administered radiopharmaceuticals

International Nuclear Information System (INIS)

Roedler, H.D.; Kaul, A.

1975-01-01

The use of radiopharmaceuticals for medical examinations is increasing. Surveys carried out in West Berlin show a 20% average yearly increase in such examinations. This implies an increased genetic and somatic radiation exposure of the population in general. Determination of radiation exposure of the population as well as of individual patients examined requires a knowledge of the radiation dose absorbed by each organ affected by each examination. An extensive survey of the literature revealed that different authors reported widely different dose values for the same defined examination methods and radiopharmaceuticals. The reason for this can be found in the uncertainty of the available biokinetic data for dose calculations and in the application of various mathematical models to describe the kinetics and calculation of organ doses. Therefore, the authors recalculated some of the dose values published for radiopharmaceuticals used in patients by applying biokinetic data obtained from exponential models of usable metabolism data reported in the literature. The calculation of organ dose values was done according to the concept of absorbed fractions in its extended form. For all radiopharmaceuticals used in nuclear medicine the energy dose values for the most important organs (ovaries, testicles, liver, lungs, spleen, kidneys, skeleton, total body or residual body) were recalculated and tabulated for the gonads, skeleton and critical or examined organs respectively. These dose values are compared with those reported in the literature and the reasons for the observed deviations are discussed. On the basis of recalculated dose values for the gonads and bone-marrow as well as on the basis of results of statistical surveys in West Berlin, the genetically significant dose and the somatically (leukemia) significant dose were calculated for 1970 and estimated for 1975. For 1970 the GSD was 0.2 mrad and the LSD was 0.7 mrad. For 1975 the GSD is estimated at < 0.5 mrad and the

Biodegradation at Dynamic Plume Fringes: Mixing Versus Reaction Control

Science.gov (United States)

Cirpka, O. A.; Eckert, D.; Griebler, C.; Haberer, C.; Kürzinger, P.; Bauer, R.; Mellage, A.

2014-12-01

Biodegradation of continuously emitted plumes is known to be most pronounced at the plume fringe, where mixing of contaminated water and ambient groundwater, containing dissolved electron acceptors, stimulates microbial activity. Under steady-state conditions, physical mixing of contaminant and electron acceptor by transverse dispersion was shown to be the major bottleneck for biodegradation, with plume lengths scaling inversely with the bulk transverse dispersivity in quasi two-dimensional settings. Under these conditions, the presence of suitable microbes is essential but the biokinetic parameters do not play an important role. When the location of the plume shifts (caused, e.g., by a fluctuating groundwater table), however, the bacteria are no more situated at the plume fringe and biomass growth, decay, activation and deactivation determine the time lag until the fringe-controlled steady state is approached again. During this time lag, degradation is incomplete. The objective of the presented study was to analyze to which extent flow and transport dynamics diminish effectiveness of fringe-controlled biodegradation and which microbial processes and related biokinetic parameters determine the system response in overall degradation to hydraulic fluctuations. We performed experiments in quasi-two-dimensional flow through microcosms on aerobic toluene degradation by Pseudomonas putida F1. Plume dynamics were simulated by vertical alteration of the toluene plume position and experimental results were analyzed by reactive-transport modeling. We found that, even after disappearance of the toluene plume for two weeks, the majority of microorganisms stayed attached to the sediment and regained their full biodegradation potential within two days after reappearance of the toluene plume. Our results underline that besides microbial growth and maintenance (often subsumed as "biomass decay") microbial dormancy (that is, change into a metabolically inactive state) and

Radioactivity studies. Progress report, January 1-December 31, 1982

International Nuclear Information System (INIS)

Cohen, N.

1983-06-01

During the last year, the research program in actinide biokinetics in nonhuman primates has been expanded to include preliminary studies of the element neptunium. Recently, Np-237, which is known to be present in high-level nuclear reactor waste, has received increased attention as a potential long-range hazard to man. In addition to the neptunium studies, the metabolism of protactinium-233, the daughter of Np-237, has been investigated. Although characterization of Pa-233 metabolism was originally conducted in order to correct for Pa-233 interference during in vivo and in vitro gamma spectrometry of Np-237, several other considerations indicated that Pa might be of radiological concern itself and should thereby warrant further investigation. Due to the limited amount of data in the literature defining the biokinetics of both neptunium and protactinium, metabolis studies of these nuclides are now being conducted in adult female baboons in a manner similar to that which has been successfully performed at this laboratory for Am-241 and Cm-243,244. Procedures routinely performed include external whole-body counting, excreta collection (separation and measurement), blood sampling, biopsies of liver and bone, and complete tissue and organ analysis after sacrifice

Dosimetry of internal emitters - quo vadis?

International Nuclear Information System (INIS)

Reddy, A.R.; Nagaratnam, A.; Jain, S.C.; Gupta, M.M.; Mehta, S.C.

1999-01-01

The dosimetry of internally administered radiopharmaceuticals in nuclear medicine procedures using MIRD formalisms and dosimetry in the case of intakes of radionuclides and ICRP methodology for the purpose of radiological protection are well established working practices. It should, however, be remembered that dose or dose coefficients calculated refer to a reference individual, defined in terms of a mathematical phantom established on the basis of certain biokinetic reference parameters. The reference individual represents a typical caucasian adult of West Europe or North American origin. Recently, some attempts have been made to define a Reference Asian and a Reference Indian individual and to assess the effects of anatomical differences and changes in the biokinetics of radiopharmaceuticals and other radionuclides in these different reference individuals on the estimation of dose and dose coefficients in relation to the intake of internal radionuclides. The assessment of doses to the embryo/fetus due to intake of radionuclides by pregnant women, local dose estimates, microdosimetry, radiobiology and radiation protection aspects relating to Auger electron emitters represent other areas of active research in the area of dosimetry of internal emitters. The present review summarises these different aspects of work. (orig.) [de

Scaling animal to human biodistribution of the radiopharmaceutical [68Ga]Ga-PSMA-HBED-CC

Energy Technology Data Exchange (ETDEWEB)

Parra, Pamela Ochoa, E-mail: lapochoap@unal.edu.co; Veloza, Stella [Grupo de Física Nuclear, Departamento de Física, Universidad Nacional de Colombia, Bogota, D.C. (Colombia)

2016-07-07

The radiotracer called {sup 68}Ga-labelled Glu-urea-Lys(Ahx)-HBED-CC ([68Ga]Ga-PSMA-HBED-CC) is a novel radiophar-maceutical for the detection of prostate cancer lesions by positron emission tomography (PET) imaging. Setting up a cost-effective manual synthesis of this radiotracer and making its clinical translation in Colombia will require two important elements: the evaluation of the procedure to yield a consistent product, meeting standards of radio-chemical purity and low toxicity and then, the evaluation of the radiation dosimetry. In this paper a protocol to extrapolate the biokinetic model made in normal mice to humans by using the computer software for internal dose assessment OLINDA/EXM® is presented as an accurate and standardized method for the calculation of radiation dosimetry estimates.

Improving the Assessment of Internal Occupational Exposure to Natural Uranium from Urinalysis by Normalization to Creatinine

International Nuclear Information System (INIS)

Marko, R.; Kol, R.; Katorza, E.; German, U.; Balaish, Y.; Lorber, A.; Karpas, Z.

2002-01-01

The assessment of occupational internal exposure to natural uranium is normally carried out by combining Uranium Lung Detection (ULD) and urine analysis. The ULD is a direct measurement of the uranium content in lungs. The urine analysis measures the amount of uranium excreted from the body. The biokinetic models that are in use for dose assessments from urine analysis measurements are usually based on 24-hour urine collection. There are three traditional methods to collect urine samples: a) 24-hour collection - the subject is asked to collect all the urine excreted during a 24-hour period. b) Simulated 24-hour collection - the subject collects all the urine excreted during three consecutive 8-hour workdays. c) Spot samples - the subject gives a single urine sample at some time during work hours

Process optimization and analysis of product inhibition kinetics of crude glycerol fermentation for 1,3-Dihydroxyacetone production.

Science.gov (United States)

Dikshit, Pritam Kumar; Padhi, Susant Kumar; Moholkar, Vijayanand S

2017-11-01

In present study, statistical optimization of biodiesel-derived crude glycerol fermentation to DHA by immobilized G. oxydans cells over polyurethane foam is reported. Effect of DHA (product) inhibition on crude glycerol fermentation was analyzed using conventional biokinetic models and new model that accounts for both substrate and product inhibition. Optimum values of fermentation parameters were: pH=4.7, temperature=31°C, initial substrate concentration=20g/L. At optimum conditions, DHA yield was 89% (17.83g/L). Effect of product inhibition on fermentation was trivial for DHA concentrations ≤30g/L. At higher concentrations (≥50g/L), kinetics and yield of fermentation showed marked reduction with sharp drop in V max and K S values. Inhibition effect was more pronounced for immobilized cells due to restricted transport of fermentation mixture across polyurethane foam. Retention of fermentation mixture in immobilized matrix resulted in higher localized DHA concentration that possibly enhanced inhibition effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

AGE-DEPENDENT INHALATION DOSE DUE TO EXPOSURE OF SHORT LIVED PROGENY OF RADON AND THORON FOR DIFFERENT AGE GROUPS IN JAMMU & KASHMIR, HIMALAYAS.

Science.gov (United States)

Sharma, Sumit; Kumar, Ajay; Mehra, Rohit

2018-05-16

Dosimetric approach is used in this study for the assessment of doses due to inhalation of short lived radon/thoron progeny to the inhabitants of Udhampur district of Jammu & Kashmir. This paper also presents the activity concentrations and unattached fraction of radon and thoron progeny. The observed annual concentration of attached and unattached 222Rn and 220Rn progeny has been found to vary from 8 to 32 and 0.09 to 14 Bq/m3, 0.75 to 3.16 and 0.01 to 1.13 Bq/m3, respectively. The inhalation doses from radon progeny to different body organs of different age groups have been calculated by using the age dependent biokinetic model. The attachment rate of 222Rn and indoor aerosol concentration of 222Rn and 220Rn have been estimated and their relation between them has also been studied. The dose conversion factor for mouth and nasal breathing to different exposure conditions has been obtained from Porstendorfer model.

Final report on the Project Research 'Assessment of Human Exposure to Environmental Radiation'

International Nuclear Information System (INIS)

1989-03-01

This is the final report of the Project Research, 'Assessment of Human Exposure to Environmental Radiation', which has been conducted during the period 1983-1988. With the objective of assessing risk of environmental radioactivity to the population, the Project was divided into the following five research groups: (1) research for establishing calculation models and parameters in transfer of radionuclides from crop species through the human body; (2) research for analyzing transfer of radionuclides in the ocean and their contributions to exposure doses in the human body; (3) research for surveying accuracy of exposure models for the external body and respiratory organ and the influential factors; (4) research for determining uptake and biokinetics of radionuclides in the body; and (5) research for estimating and evaluating physical and physiological characteristics of reference Japanese man and the populaltion doses. Effluents from nuclear power plants and reprocessing plants were regarded as radionuclide sources in the water and atmosphere. (N.K.)

Dose coefficients for radionuclides produced in high energy proton accelerator facilities. Coefficients for radionuclides not listed in ICRP publications

CERN Document Server

Kawai, K; Noguchi, H

2002-01-01

Effective dose coefficients, the committed effective dose per unit intake, by inhalation and ingestion have been calculated for 304 nuclides, including (1) 230 nuclides with half-lives >= 10 min and their daughters that are not listed in ICRP Publications and (2) 74 nuclides with half-lives < 10 min that are produced in a spallation target. Effective dose coefficients for inhalation of soluble or reactive gases have been calculated for 21 nuclides, and effective dose rates for inert gases have been calculated for 9 nuclides. Dose calculation was carried out using a general-purpose nuclear decay database DECDC developed at JAERI and a decay data library newly compiled from the ENSDF for the nuclides abundantly produced in a spallation target. The dose coefficients were calculated with the computer code DOCAP based on the respiratory tract model and biokinetic model of ICRP. The effective dose rates were calculated by considering both external irradiation from the surrounding cloud and irradiation of the lun...

MEDOR, a didactic tool to support interpretation of bioassay data after internal contamination by actinides

Energy Technology Data Exchange (ETDEWEB)

Miele, A.; Blanchin, N. [Service medical du travail, CEA Cadarache, 13108 Saint Paul lez Durance (France); Raynaud, P. [Service de sante au travail, COGEMA Marcoule, 30207 Bagnols sur Ceze (France); Quesne, B. [COGEMA-AREVA, BP 4, 78141 Velizy (France); Giraud, J.M.; Piechowski, J. [CEA, 31 rue de la Federation, 75752 Paris Cedex 15 (France); Fottorino, R. [Laboratoire d' analyses de biologie medicale, CEA Cadarache, 13108 Saint Paul lez Durance (France); Berard, P. [Laboratoire d' Analyses BioMedicales, DSM, CEA Saclay, 91191 Gif sur Yvette (France); Ansoborlo, E. [CETAMA DRCP/DEN/CEAVALRHO Marcoule, BP 17171, 30207 Bagnols sur Ceze (France); Franck, D.; Blanchardon, E.; Challeton-de Vathaire, C. [Laboratoire d' evaluation de la dose interne, IRSN, BP 17, 92262 Fontenay-aux-Roses Cedex (France); Lebaron-Jacobs, L. [CARMIN, CEA/DSV, BP 6, 92262 Fontenay-aux-Roses Cedex (France); Poncy, J.L.; Fritsch, P. [Laboratoire de Radiotoxicologie, SRCA/DRR/DSV/CEA, BP 12, 91680 Bruyeres le Chatel (France)

2007-07-01

A didactic software, Methodes Dosimetriques de Reference (MEDOR), is being developed to provide help in the interpretation of biological data. Its main purpose is to evaluate the pertinence of the application of different models. This paper describes its first version that is focused on inhalation exposure to actinide aerosols. With this tool, sensitivity analysis on different parameters of the ICRP models can be easily done for aerosol deposition, in terms of activity and particle number, actinide biokinetics and doses. The user can analyse different inhalation cases showing either that dose per unit intake cannot be applied if the aerosol contains a low number of particles or that an inhibition of the late pulmonary clearance by particle transport can occur which contributes to a 3-4 fold increase in effective dose as compared with application of default parameters. This underlines the need to estimate systematically the number of deposited particles, as well as to do chest monitoring as long as possible. (authors)

MEDOR, a didactic tool to support interpretation of bioassay data after internal contamination by actinides

International Nuclear Information System (INIS)

Miele, A.; Blanchin, N.; Raynaud, P.; Quesne, B.; Giraud, J.M.; Piechowski, J.; Fottorino, R.; Berard, P.; Ansoborlo, E.; Franck, D.; Blanchardon, E.; Challeton-de Vathaire, C.; Lebaron-Jacobs, L.; Poncy, J.L.; Fritsch, P.

2007-01-01

A didactic software, Methodes Dosimetriques de Reference (MEDOR), is being developed to provide help in the interpretation of biological data. Its main purpose is to evaluate the pertinence of the application of different models. This paper describes its first version that is focused on inhalation exposure to actinide aerosols. With this tool, sensitivity analysis on different parameters of the ICRP models can be easily done for aerosol deposition, in terms of activity and particle number, actinide biokinetics and doses. The user can analyse different inhalation cases showing either that dose per unit intake cannot be applied if the aerosol contains a low number of particles or that an inhibition of the late pulmonary clearance by particle transport can occur which contributes to a 3-4 fold increase in effective dose as compared with application of default parameters. This underlines the need to estimate systematically the number of deposited particles, as well as to do chest monitoring as long as possible. (authors)

Reassessment of tritium dose coefficients for the general public

International Nuclear Information System (INIS)

Melintescu, A.; Galeriu, D.; Takeda, H.

2007-01-01

Concerns of increased risk from tritium intake by humans have been claimed in the past. The arguments concerning the radiobiological effectiveness of tritium, its longer retention in the human body and the presence of tritium in the DNA hydration shell are analysed in this paper. A biokinetic model for tritiated water and organically bound tritium retention in the human body is used, based on a common approach for mammals using energy and hydrogen metabolism and tested separately with animal experiments. Extension to this model to humans considers the increased role of the brain, food quality and unique growth patterns of humans. Various ages and genders for Caucasians are considered. For an intake of tritium in organic forms in the diet, the retention for the female is of about a factor 2 compared with ICRP recommendations. Effective dose coefficients are estimated to be about a factor of 2 to 3 higher than those of the ICRP. (authors)

What is New in Internal Dosimetry and Monitoring?

Energy Technology Data Exchange (ETDEWEB)

Henrichs, K. [Siemens AG, Corporate Radiation Safety and Dangerous Goods Transport, Munich (Germany); Nosske, D. [Federal Office for Radiation Protection, Neuherberg (Germany)

2006-07-01

This file is divided in two parts:the first one concerns the progress in internal dosimetry. This part gives an overview on new model developments by ICRP, the series of age dependent doses for members of the public was continued by biokinetic and dosimetric models for the embryo and foetus due to activity intake by the mother (ICRP,2001) and for the infant via consumption of mother's milk after activity intake by the mother (ICRP, 2004). In both publications dose coefficients for the embryo and foetus as well the infant were given for various intake scenarios by mother. The present model development work of ICRP is a revision of Publications 30, 54, 68, and 78 based on the new human Alimentary tract model (H.A.T.M.) of ICRP (ICRP, 2006), a revision of absorption parameters for the human respiratory tract model (ICRP, 1994a), new systemic models as well as new dosimetric parameters derived with new Voxel models for the reference male and female adult. The second part concerns the progress in workers monitoring for radionuclide intake. The initiatives to improve the situation are the guidelines published by the International Atomic Energy Agency (2004), giving guidance for the assessment of occupational exposures due to intakes of radionuclides, research project funded by the European Commission: the objective of O.M.I.N.E.X. was the improvement of monitoring programmes, taking into account the uncertainties of biokinetic models and data, the programme I.D.E.A. tried to improve measuring techniques and I.D.E.A.S derives rules for the evaluation of measured activity values in terms of exposure. Standardization projects by the International Standardization Organization I.S.O.: I.S.O. (2001) published a standard defining the requirements for bioassay laboratories, which will soon followed by a second part giving the rationale behind these rules., presently the final version (I.S.O. 2005) of a standard is circulating among the I.S.O. member states which guidance on

Absorbed dose in the fetus of a pregnant patient when I{sup 131} (iodide/Tc{sup 99m} (pertechnetate) is administered during thyroid studies; Dosis absorbida en el feto de una paciente embarazada cuando se administra I{sup 131} (yoduro)/Tc{sup 99m} (pertecnetato) durante estudios tiroideos

Energy Technology Data Exchange (ETDEWEB)

Vasquez A, M.; Murillo C, V.; Arbayza F, J.; Sanchez S, P.; Cabrera S, C., E-mail: marvva@hotmail.com [Universidad Nacional de Trujillo, Laboratorio de Fisica Nuclear, Trujillo (Peru)

2016-10-15

The radiation absorbed dose in the fetus of a pregnant woman during thyroid studies is estimated through the analysis of the bio-kinetics of radiopharmaceuticals containing I{sup 131} (iodide) or Tc{sup 99m} (pertechnetate). MIRD formalism and its representation Cristy-Eckerman are used. The results indicate that the absorbed dose by the fetus of a woman of 3, 6 and 9 months of gestation due to Tc{sup 99m} emissions is lower than that obtained by I{sup 131}; represent 34.7%, 6% and 3.5% of the dose generate by the iodide. The auto-dose in the fetus of a pregnant woman is mainly due to the local energy deposition of the beta and gamma emissions of I{sup 131}, being greater than the one reported by the gamma emissions and conversion electrons of the Tc{sup 99m}, for fetuses of 6 and 9 months. The dose incorporated to the fetus due to the organs of the maternal tissues, which are part of the bio-kinetics, are basically due to the emission of its gamma photons and correspond to 38.50% /60.52% in fetuses of 3 months, 64.71% /12.43% in fetuses of 6 months and 69.79% /10.97% in fetuses of 9 months for the radiopharmaceuticals Tc{sup 99m} (pertechnetate) / I{sup 131} (iodide). The organs of bio-kinetics that contribute to the fetus dose are mainly due to the bladder, followed by the rest, and small intestine (fetuses of 3 months); of the rest, followed by the small intestine and bladder (fetuses of 6 months); of the bladder, followed by the small intestine and stomach (fetuses of 9 months) when using I{sup 131}; while for the Tc{sup 99m} the bladder and rest contribute (fetuses of 3 months); of the placenta, followed by the rest and bladder (fetuses of 6 and 9 months). (Author)

Absorbed dose in the fetus of a pregnant patient when I"1"3"1 (iodide/Tc"9"9"m (pertechnetate) is administered during thyroid studies

International Nuclear Information System (INIS)

Vasquez A, M.; Murillo C, V.; Arbayza F, J.; Sanchez S, P.; Cabrera S, C.

2016-10-01

The radiation absorbed dose in the fetus of a pregnant woman during thyroid studies is estimated through the analysis of the bio-kinetics of radiopharmaceuticals containing I"1"3"1 (iodide) or Tc"9"9"m (pertechnetate). MIRD formalism and its representation Cristy-Eckerman are used. The results indicate that the absorbed dose by the fetus of a woman of 3, 6 and 9 months of gestation due to Tc"9"9"m emissions is lower than that obtained by I"1"3"1; represent 34.7%, 6% and 3.5% of the dose generate by the iodide. The auto-dose in the fetus of a pregnant woman is mainly due to the local energy deposition of the beta and gamma emissions of I"1"3"1, being greater than the one reported by the gamma emissions and conversion electrons of the Tc"9"9"m, for fetuses of 6 and 9 months. The dose incorporated to the fetus due to the organs of the maternal tissues, which are part of the bio-kinetics, are basically due to the emission of its gamma photons and correspond to 38.50% /60.52% in fetuses of 3 months, 64.71% /12.43% in fetuses of 6 months and 69.79% /10.97% in fetuses of 9 months for the radiopharmaceuticals Tc"9"9"m (pertechnetate) / I"1"3"1 (iodide). The organs of bio-kinetics that contribute to the fetus dose are mainly due to the bladder, followed by the rest, and small intestine (fetuses of 3 months); of the rest, followed by the small intestine and bladder (fetuses of 6 months); of the bladder, followed by the small intestine and stomach (fetuses of 9 months) when using I"1"3"1; while for the Tc"9"9"m the bladder and rest contribute (fetuses of 3 months); of the placenta, followed by the rest and bladder (fetuses of 6 and 9 months). (Author)

Arsenic bioaccumulation in a marine juvenile fish Terapon jarbua

International Nuclear Information System (INIS)

Zhang Wei; Huang Liangmin; Wang Wenxiong

2011-01-01

Highlights: Radiotracer technique was used to quantify the biokinetics of As(V) in a marine fish. As(V) had a low bioavailability to Terapon jarbua. Dietary assimilation of As was only 3.1–7.4% for fish fed with different preys. Dietary uptake could be the primary route for As bioaccumulation in fish. - Abstract: Arsenic (As) is a ubiquitous toxic metalloid that is causing widespread public concern. Recent measurements have indicated that some marine fish in China might be seriously contaminated with As. Yet the biokinetics and bioaccumulation pathway of As in fish remain little understood. In this study, we employed a radiotracer technique to quantify the dissolved uptake, dietary assimilation and subsequent efflux of As(V) in a marine predatory fish, Terapon jarbua. The dissolved uptake of As showed a linear pattern over a range of dissolved concentrations from 0.5 to 50 μg L −1 , with a corresponding uptake rate constant of 0.0015 L g −1 d −1 . The assimilation efficiencies (AEs) of dietary As were only 3.1–7.4% for fish fed with copepods, clams, prey fish, or artificial diets, and were much lower than the As that entered the trophically available metal fraction in the prey. The dietary AEs were independent of the As(V) concentrations in the artificial diets. The efflux rate constant of As in fish following the dietary exposure was 0.03 d −1 . Modeling calculations showed that dietary uptake could be the primary route for As bioaccumulation in fish, and the corresponding contributions of waterborne and dietary uptakes were related to the bioconcentration factor (BCF) of the prey and the ingestion rate of fish. This study demonstrates that As(V) has a low bioavailability to T. jarbua.

Monitoring of persons with injuries with incorporated radioactive material; Monitoração de pessoas com ferimentos com material radioativo incorporado

Energy Technology Data Exchange (ETDEWEB)

Lopes, A.G.; Tauhata, L., E-mail: amandglird@gmail.com [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil). Lab. Nacional de Metrologia das Radiações Ionizantes; Bertelli, L. [Radiation Protection Division, Los Alamos National Laboratory, Los Alamos, NM (United States)

2017-07-01

The monitoring of victims with injuries with incorporated radioactive material can be performed with portable detectors in initial evaluations, with unshielded measurements, collimation, often with the ignorance of the radionuclide, and also, in the posterior medical follow-up with whole-body detectors and HPGe, in measurements of body or urine activity in periodic measurements. Dosimetry in these situations is done using appropriate models, which surpass those of orthodox internal dosimetry, the biokinetic model described in the 2006 NCRP, such as the AIDE models, and the one developed by Deepesh for the {sup 241}Am. Using tissue-equivalent material, measurements were made with portable detectors to obtain the values of the total attenuation coefficient for the {sup 241}Am radiation and compared to the NIST tables. Measurements were also made with the fixed detectors for certification of the measurement procedure. The percentage deviations obtained in relation to the theoretical ones were: PRD (55%) and IdentiFINDER2 (72%). First-aid monitoring measurements may present great uncertainties and differences of accuracy, but are important data to guide the medical treatment of the victims of accidents.

Monitoring of persons with injuries with incorporated radioactive material

International Nuclear Information System (INIS)

Lopes, A.G.; Tauhata, L.

2017-01-01

The monitoring of victims with injuries with incorporated radioactive material can be performed with portable detectors in initial evaluations, with unshielded measurements, collimation, often with the ignorance of the radionuclide, and also, in the posterior medical follow-up with whole-body detectors and HPGe, in measurements of body or urine activity in periodic measurements. Dosimetry in these situations is done using appropriate models, which surpass those of orthodox internal dosimetry, the biokinetic model described in the 2006 NCRP, such as the AIDE models, and the one developed by Deepesh for the 241 Am. Using tissue-equivalent material, measurements were made with portable detectors to obtain the values of the total attenuation coefficient for the 241 Am radiation and compared to the NIST tables. Measurements were also made with the fixed detectors for certification of the measurement procedure. The percentage deviations obtained in relation to the theoretical ones were: PRD (55%) and IdentiFINDER2 (72%). First-aid monitoring measurements may present great uncertainties and differences of accuracy, but are important data to guide the medical treatment of the victims of accidents

Modeling The Skeleton Weight of an Adult Caucasian Man.

Science.gov (United States)

Avtandilashvili, Maia; Tolmachev, Sergei Y

2018-05-17

biokinetic modeling of U.S. Transuranium and Uranium Registries partial-body donation cases.

The fate of calcium carbonate nanoparticles administered by oral route: absorption and their interaction with biological matrices

Directory of Open Access Journals (Sweden)

Lee JA

2015-03-01

Full Text Available Jeong-A Lee,1,* Mi-Kyung Kim,1,* Hyoung-Mi Kim,2,* Jong Kwon Lee,3 Jayoung Jeong,4 Young-Rok Kim,5 Jae-Min Oh,2 Soo-Jin Choi1 1Department of Food Science and Technology, Seoul Women’s University, Seoul, Republic of Korea; 2Department of Chemistry and Medical Chemistry, College of Science and Technology, Yonsei University, Wonju, Republic of Korea; 3Hazard Substances Analysis Division, Gwangju Regional Food and Drug Administration, Ministry of Food and Drug Safety, Gwangju, Republic of Korea; 4Toxicological Research Division, National Institute of Food and Drug Safety Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do, Republic of Korea; 5Department of Food Science and Biotechnology, Kyung Hee University, Yongin, Republic of Korea *These authors contributed equally to this work Background: Orally administered particles rapidly interact with biological fluids containing proteins, enzymes, electrolytes, and other biomolecules to eventually form particles covered by a corona, and this corona potentially affects particle uptake, fate, absorption, distribution, and elimination in vivo. This study explored relationships between the biological interactions of calcium carbonate particles and their biokinetics.Methods: We examined the effects of food grade calcium carbonates of different particle size (nano [N-Cal] and bulk [B-Cal]: specific surface areas of 15.8 and 0.83 m2/g, respectively on biological interactions in in vitro simulated physiological fluids, ex vivo biofluids, and in vivo in gastrointestinal fluid. Moreover, absorption and tissue distribution of calcium carbonates were evaluated following a single dose oral administration to rats.Results: N-Cal interacted more with biomatrices than bulk materials in vitro and ex vivo, as evidenced by high fluorescence quenching ratios, but it did not interact more actively with biomatrices in vivo. Analysis of coronas revealed that immunoglobulin, apolipoprotein, thrombin, and fibrinogen

Internal dosimetry for [4-{sup 14}C]-cholesterol in humans

Energy Technology Data Exchange (ETDEWEB)

Marcato, Larissa A.; Mesquita, Carlos H. de, E-mail: chmesqui@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Cesar, Thais B., E-mail: tcesar@fcfar.unesp.b [Universidade Estadual Paulista Julio de Mesquita Filho (FCF/UNESP), Araraquara, SP (Brazil). Fac. de Ciencias Farmaceuticas. Dept. de Alimentos e Nutricao; Vinagre, Carmen G.C. [Universidade de Sao Paulo (InCor/HCFMUSP), SP (Brazil). Hospital das Clinicas. Instituto do Coracao

2011-07-01

This study proposes a biokinetic model for use in the assessment of the internal dose received by human subjects administered orally with [4-{sup 14}C]-cholesterol. The proposed model includes three systemic pools representing the short-term (T1/2 = 1 d), intermediate-term (T1/2 = 16 d) and long-term (T1/2 = 78 d) physiological exchanges and two excretion pathways: urine and feces. This model used the ANACOMP software to estimate radiometric doses with MIRD techniques (Medical Internal Radiation Dose). To validate the model, the profile curve of excretion prediction by the model in the range of seven days was compared with those curves described in literature. No statistical difference was detected (P = 0.416). The estimated effective dose coefficient calculated for the reference man described on ICRP publication 23 was 3.39x10{sup -10} SvBq{sup -1}. The organs that received the highest equivalent dose were the lower large intestine (2.459x10{sup -9} GyBq{sup -1}), upper large intestine (9.023x10{sup -10} GyBq{sup -1}) and small intestine (3.717x10{sup -10} GyBq{sup -1}). (author)

Internal dosimetry for [4-14C]-cholesterol in humans

International Nuclear Information System (INIS)

Marcato, Larissa A.; Mesquita, Carlos H. de; Cesar, Thais B.; Vinagre, Carmen G.C.

2011-01-01

This study proposes a biokinetic model for use in the assessment of the internal dose received by human subjects administered orally with [4- 14 C]-cholesterol. The proposed model includes three systemic pools representing the short-term (T1/2 = 1 d), intermediate-term (T1/2 = 16 d) and long-term (T1/2 = 78 d) physiological exchanges and two excretion pathways: urine and feces. This model used the ANACOMP software to estimate radiometric doses with MIRD techniques (Medical Internal Radiation Dose). To validate the model, the profile curve of excretion prediction by the model in the range of seven days was compared with those curves described in literature. No statistical difference was detected (P = 0.416). The estimated effective dose coefficient calculated for the reference man described on ICRP publication 23 was 3.39x10 -10 SvBq -1 . The organs that received the highest equivalent dose were the lower large intestine (2.459x10 -9 GyBq -1 ), upper large intestine (9.023x10 -10 GyBq -1 ) and small intestine (3.717x10 -10 GyBq -1 ). (author)

Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images.

Science.gov (United States)

Leal Neto, Viriato; Vieira, José Wilson; Lima, Fernando Roberto de Andrade

2014-01-01

This article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. A software called DoRadIo (Dosimetria das Radiações Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C# programming language. With the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. The user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity.

Modelling growth of Penicillium expansum and Aspergillus niger at constant and fluctuating temperature conditions.

Science.gov (United States)

Gougouli, Maria; Koutsoumanis, Konstantinos P

2010-06-15

The growth of Penicillium expansum and Aspergillus niger, isolated from yogurt production environment, was investigated on malt extract agar with pH=4.2 and a(w)=0.997, simulating yogurt, at isothermal conditions ranging from -1.3 to 35 degrees C and from 5 to 42.3 degrees C, respectively. The growth rate (mu) and (apparent) lag time (lambda) of the mycelium growth were modelled as a function of temperature using a Cardinal Model with Inflection (CMI). The results showed that the CMI can describe successfully the effect of temperature on fungal growth within the entire biokinetic range for both isolates. The estimated values of the CMI for mu were T(min)=-5.74 degrees C, T(max)=30.97 degrees C, T(opt)=22.08 degrees C and mu(opt)=0.221 mm/h for P. expansum and T(min)=10.13 degrees C, T(max)=43.13 degrees C, T(opt)=31.44 degrees C, and mu(opt)=0.840 mm/h for A. niger. The cardinal values for lambda were very close to the respective values for mu indicating similar temperature dependence of the growth rate and the lag time of the mycelium growth. The developed models were further validated under fluctuating temperature conditions using various dynamic temperature scenarios. The time-temperature conditions studied included single temperature shifts before or after the end of the lag time and continuous periodic temperature fluctuations. The prediction of growth at changing temperature was based on the assumption that after a temperature shift the growth rate is adopted instantaneously to the new temperature, while the lag time was predicted using a cumulative lag approach. The results showed that when the temperature shifts occurred before the end of the lag, they did not cause any significant additional lag and the observed total lag was very close to the cumulative lag predicted by the model. In experiments with temperature shifts after the end of the lag time, accurate predictions were obtained when the temperature profile included temperatures which were inside the

In vitro and in vivo approaches for the measurement of oral bioavailability of lead (Pb) in contaminated soils: A review

International Nuclear Information System (INIS)

Zia, Munir Hussain; Codling, Eton E.; Scheckel, Kirk G.; Chaney, Rufus L.

2011-01-01

We reviewed the published evidence of lead (Pb) contamination of urban soils, soil Pb risk to children through hand-to-mouth activity, reduction of soil Pb bioavailability due to soil amendments, and methods to assess bioaccessibility which correlate with bioavailability of soil Pb. Feeding tests have shown that urban soils may have much lower Pb bioavailability than previously assumed. Hence bioavailability of soil Pb is the important measure for protection of public health, not total soil Pb. Chemical extraction tests (Pb bioaccessibility) have been developed which are well correlated with the results of bioavailability tests; application of these tests can save money and time compared with feeding tests. Recent findings have revealed that fractional bioaccessibility (bioaccessible compared to total) of Pb in urban soils is only 5-10% of total soil Pb, far lower than the 60% as bioavailable as food-Pb presumed by U.S.-EPA (30% absolute bioavailability used in IEUBK model). - Highlights: → Among direct exposure pathways for Pb in urban environments, inadvertent ingestion of soil is considered the major concern. → The concentration of lead in house dusts is significantly related to that in garden soil, and is highest at older homes. → In modeling risks from diet/water/soil Pb, US-EPA presumes that soil-Pb is 60% as bioavailable as other dietary Pb. → Joplin study proved that RBALP method seriously underestimated the ability of phosphate treatments to reduce soil Pb bioavailability. → Zia et al. method has revealed that urban soils have only 5-10% bioaccessible Pb of total Pb level. - Improved risk evaluation and recommendations for Pb contaminated soils should be based on bioavailability-correlated bioaccessible soil Pb rather than total soil Pb.

Synchrotron-based nu-XRF mapping and mu-FTIR microscopy enable to look into the fate and effects of tattoo pigments in human skin

OpenAIRE

Schreiver , Ines; Hesse , Bernhard; Seim , Christian; Castillo-Michel , Hiram; Villanova , Julie; Laux , Peter; Dreiack , Nadine; Penning , Randolf; Tucoulou , Remi; Cotte , Marine; Luch , Andreas

2017-01-01

International audience; The increasing prevalence of tattoos provoked safety concerns with respect to particle distribution and effects inside the human body. We used skin and lymphatic tissues from human corpses to address local biokinetics by means of synchrotron X-ray fluorescence (XRF) techniques at both the micro (mu) and nano (nu) scale. Additional advanced mass spectrometry-based methodology enabled to demonstrate simultaneous transport of organic pigments, heavy metals and titanium di...

The effect of somatic awareness exercise on the chronic physical manifestations of the stress response

OpenAIRE

2013-01-01

M.Phil. (Biokinetics) Stress is an integral part of daily living and supports the ability to adapt. However, chronic activation without the ability to express the physical response results in overloading the physiological and psychological systems. Since urban South Africans are sedentary and experience high levels of stress, they are developing stress related chronic conditions and hypokinetic diseases (obesity, hypertension, depression). This study is aimed at decreasing the chronic phys...

Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images*

Science.gov (United States)

Leal Neto, Viriato; Vieira, José Wilson; Lima, Fernando Roberto de Andrade

2014-01-01

Objective This article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. Materials and Methods A software called DoRadIo (Dosimetria das Radiações Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C# programming language. Results With the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. Conclusion The user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity. PMID:25741101

Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images

International Nuclear Information System (INIS)

Leal Neto, Viriato; Vieira, Jose Wilson; Lima, Fernando Roberto de Andrade

2014-01-01

Objective: this article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. Materials and methods: a software called DoRadIo (Dosimetria das Radiacoes Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C ⧣ programming language. Results: with the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. Conclusion: the user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity. (author)

Application for internal dosimetry using biokinetic distribution of photons based on nuclear medicine images

Energy Technology Data Exchange (ETDEWEB)

Leal Neto, Viriato, E-mail: viriatoleal@yahoo.com.br [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco (IFPE), Recife, PE (Brazil); Vieira, Jose Wilson [Universidade Federal de Pernambuco (UPE), Recife, PE (Brazil); Lima, Fernando Roberto de Andrade [Centro Regional de Ciencias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

2014-09-15

Objective: this article presents a way to obtain estimates of dose in patients submitted to radiotherapy with basis on the analysis of regions of interest on nuclear medicine images. Materials and methods: a software called DoRadIo (Dosimetria das Radiacoes Ionizantes [Ionizing Radiation Dosimetry]) was developed to receive information about source organs and target organs, generating graphical and numerical results. The nuclear medicine images utilized in the present study were obtained from catalogs provided by medical physicists. The simulations were performed with computational exposure models consisting of voxel phantoms coupled with the Monte Carlo EGSnrc code. The software was developed with the Microsoft Visual Studio 2010 Service Pack and the project template Windows Presentation Foundation for C ⧣ programming language. Results: with the mentioned tools, the authors obtained the file for optimization of Monte Carlo simulations using the EGSnrc; organization and compaction of dosimetry results with all radioactive sources; selection of regions of interest; evaluation of grayscale intensity in regions of interest; the file of weighted sources; and, finally, all the charts and numerical results. Conclusion: the user interface may be adapted for use in clinical nuclear medicine as a computer-aided tool to estimate the administered activity. (author)

Critical Dose of Internal Organs Internal Exposure - 13471

Energy Technology Data Exchange (ETDEWEB)

Grigoryan, G.; Amirjanyan, A. [Nuclear and Radiation Safety Centre (Armenia); Grigoryan, N. [Yerevan State Medical University 4Tigran Mets,375010 Yerevan (Armenia)

2013-07-01

The health threat posed by radionuclides has stimulated increased efforts to developed characterization on the biological behavior of radionuclides in humans in all ages. In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is assembling a set of age specific biokinetic models for environmentally important radioelements. Radioactive substances in the air, mainly through the respiratory system and digestive tract, is inside the body. Radioactive substances are unevenly distributed in various organs and tissues. Therefore, the degree of damage will depend not only on the dose of radiation have but also on the critical organ, which is the most accumulation of radioactive substances, which leads to the defeat of the entire human body. The main objective of radiation protection, to avoid exceeding the maximum permissible doses of external and internal exposure of a person to prevent the physical and genetic damage people. The maximum tolerated dose (MTD) of radiation is called a dose of radiation a person in uniform getting her for 50 years does not cause changes in the health of the exposed individual and his progeny. The following classification of critical organs, depending on the category of exposure on their degree of sensitivity to radiation: First group: the whole body, gonads and red bone marrow; Second group: muscle, fat, liver, kidney, spleen, gastrointestinal tract, lungs and lens of the eye; The third group: bone, thyroid and skin; Fourth group: the hands, forearms, feet. MTD exposure whole body, gonads and bone marrow represent the maximum exposures (5 rem per year) experienced by people in their normal activities. The purpose of this article is intended dose received from various internal organs of the radionuclides that may enter the body by inhalation, and gastrointestinal tract. The biokinetic model describes the time dependent distribution and excretion of different

Biokinetics of 237Np in two marine benthic invertebrates

International Nuclear Information System (INIS)

Guary, J.C.; Fowler, S.W.

1976-01-01

The long-lived alpha-emitting actinide 237 Np (T 1/2 = 2.2 x 10 6 y) enters the aquatic environment directly from nuclear testing and reprocessing plant wastes as well as indirectly by in situ generation from 241 Am. Earlier studies on 239 Np in the Columbia river ecosystem demonstrated that neptunium accumulated in aquatic species such as algae, sponges and insect larvae but was not detectable in higher trophic level organisms. Based on these findings and the fact that neptunium is chemically similar to the rare earth elements, it has been suggested that this actinide would not easily become incorporated into aquatic biota

Catalogue of data on uranium intake, organ burden and excretion

International Nuclear Information System (INIS)

1987-11-01

The Atomic Energy Control Board is initiating the critical evaluation of current biokinetic and dosimetric models applicable to radiation workers exposed to the common chemical and physical forms of uranium that are encountered throughout the nuclear fuel cycle. The identification and location of the relevant sets of data are the first steps of this project. This report describes the collection methods used and presents catalogues of the data on human and animal studies that have resulted from exposures under controlled experimental conditions, chronic occupational or environmental situations and acute accidental conditions. The data was identified through the use of computerized literature searches of the BIOSIS, NTIS, MEDLINE and Occupational Safety and Health (NIOSH) data bases, library research and telephone contact with currently active researchers in the field. A table is presented which categorizes researchers in the field according to affiliation and country

Technetium-99m-dimethylglyoxime ([sup 99m]Tc-DMG) as renal imaging agent

Energy Technology Data Exchange (ETDEWEB)

Adonaylo, V.N. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales Buenos Aires Univ. (Argentina). Dept. de Ciencias Biologicas); Stahl, Adriana; Pomilio, A.B.; Vitale, A.A. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales); Canellas, C.O. (Buenos Aires Univ. (Argentina). Facultad de Ciencias Exactas y Naturales Comision Nacional de Energia Atomica, Buenos Aires (Argentina))

1993-06-01

Dimethylglyoxime (DMG) labelled with [sup 99m]Tc is presented as a renal imaging agent. The behaviour of this complex was analysed at different pH by means of UV spectral data and using DMG-calcium chloride as a reference complex. Biokinetic data were evaluated in two biological models, Sprague-Dawley rats and Didelphis albiventris argentine opossum. Biodistribution in rats demonstrated fast and specific renal excretion. Time-activity values over both kidneys could be quantified for this complex. Renographic studies led to mean time-to maximum values on twelve assays of 2.0 [+-] 0.1 min and a mean relative function of 53.0 [+-] 2.3 and 47.0 [+-] 3.2 for right and left kidneys, respectively. [sup 99m]Tc-DMG showed specificity for the renal excretion pathway and therefore seems to be a very useful radiopharmaceutical for renal function studies. (Author).

Radiation physics for nuclear medicine

CERN Document Server

Hoeschen, Christoph

2011-01-01

The field of nuclear medicine is expanding rapidly, with the development of exciting new diagnostic methods and treatments. This growth is closely associated with significant advances in radiation physics. In this book, acknowledged experts explain the basic principles of radiation physics in relation to nuclear medicine and examine important novel approaches in the field. The first section is devoted to what might be termed the "building blocks" of nuclear medicine, including the mechanisms of interaction between radiation and matter and Monte Carlo codes. In subsequent sections, radiation sources for medical applications, radiopharmaceutical development and production, and radiation detectors are discussed in detail. New frontiers are then explored, including improved algorithms for image reconstruction, biokinetic models, and voxel phantoms for internal dosimetry. Both trainees and experienced practitioners and researchers will find this book to be an invaluable source of up-to-date information.

Catalogue of data on Thorium intake, organ burden and excretion

International Nuclear Information System (INIS)

1989-05-01

The Atomic Energy Control Board is initiating the critical evaluation of current biokinetic and dosimetric models applicable to estimating exposure to the common chemical and physical forms of thorium. The identification and location of the relevant sets of data are the first steps of this project. This report describes the collection methods used and presents catalogues of the data on human and animal studies that have resulted from exposures under controlled experimental conditions, chronic occupational or environmental situations and acute accidental conditions. The data was identified through the use of computerized literature searches of the Cancerlit, Chemical Exposure, Embase, BIOSIS, NTIS, INIS, MEDLINE and Occupational Safety and Health (NIOSH) data bases, library research and telephone contact with currently active researchers in the field. A table is presented which categorizes researchers in the field accordingly to affiliation and country

Optimisation of internal contamination monitoring programme by integration of uncertainties

International Nuclear Information System (INIS)

Davesne, E.; Casanova, P.; Chojnacki, E.; Paquet, F.; Blanchardon, E.

2011-01-01

Potential internal contamination of workers is monitored by periodic bioassay measurements interpreted in terms of intake and committed effective dose by the use of biokinetic and dosimetric models. After a prospective evaluation of exposure at a workplace, a suitable monitoring programme can be defined by choosing adequate measurement techniques and frequency. In this study, the sensitivity of a programme is evaluated by the minimum intake and dose, which may be detected with a given level of confidence by taking into account uncertainties on exposure conditions and measurements. This is made for programme optimisation, which is performed by comparing the sensitivities of different alternative programmes. These methods were applied at the AREVA NC reprocessing plant and support the current monitoring programme as the best compromise between the cost of the measurements and the sensitivity of the programme. (authors)

Revised dose limits and new respiratory tract model and their implications for annual limits of intake of radioactive materials - A review of recent ICRP publications

Energy Technology Data Exchange (ETDEWEB)

Schlesinger, T; Silverman, I; Shapira, M [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center

1996-12-01

Ionizing radiation may cause immediate and/or delayed biological damages to the body of the exposed person and/or his/her progeny. The exposure may be caused by an external source or may arise due to internal contamination by a radioactive material. To prevent such exposure, or to reduce the probability that it will occur, national authorities and international organizations engaged in radiation safety and protection have set limits for the exposure to ionizing radiation from either source. The sensitivity of the body to ionizing radiation usually decreases with age. For this reason and due to the limited possibilities to control the exposure of the general public, different limits have been set for for occupational exposure and for the exposure of members of the public of different age groups. The general principles of these limits and guidelines for their calculations are set by the International Commission on Radiological Protection (ICRP) and published in the Annals of the ICRP. The basic philosophy of the Commission, which includes the principles of justification, optimization and dose limits, the basic radiobiological models, and the distinction between stochastic and non-stochastic effects has been presented in its publication no. 26. Based on this philosophy, the Commission issued between 1979 and 1988 a series of publications followed by annexes and addenda known as publication no. 30. This series presented models describing the metabolism of radioactive materials which enter the body by inhalation and ingestion, the transfer of such materials from the respiratory tract and the gastrointestinal tract to the blood, and from there to the body organs and the excretion of the material from the body. This series presented also values for biokinetic parameters of these systems and transfer paths, and methods for calculating limits on intake which ensure that the exposure from internal contamination will not exceed the dose limits set.

Modelling the relationship between zooplankton biomass and environmental variations in the distribution of 210Po during a one year cycle in northwestern Mediterranean coastal waters.

Science.gov (United States)

Färber Lorda, Jaime; Tateda, Yutaka; Fowler, Scott W

2017-08-01

To clarify the relationship between zooplankton biomass and the environmental kinetics of the natural radionuclide 210 Po during a one-year period (October 1995 to November 1996) in northwestern Mediterranean coastal waters, a modelling analysis was applied. Using 210 Po concentrations in seawater and zooplankton, the 210 Po uptake rate constant from food for zooplankton was evaluated using a biokinetics calculation involving the uptake and the excretion rate constants between seawater and zooplankton. Using the transfer constants obtained, the 210 Po concentrations in zooplankton were reconstructed and validated by observed concentrations. The simulation results were in good agreement with the measured 210 Po concentrations in zooplankton. Assuming that 210 Po fecal excretion represents the majority of the excretion of 210 Po from zooplankton, the fecal matter associated 210 Po vertical flux was calculated, and compared with the observed vertical fluxes of 210 Po measured in sediment traps. The modelling evaluation showed that fecal pellet vertical transport could not fully explain the observed sinking fluxes of particulate organic matter at 150 m depth, suggesting that other sinking biodetrital aggregates are also important components of the plankton-derived vertical flux of 210 Po. The relationship between 210 Po concentration in seawater and that in rain and dry fallout and their potential effect on 210 Po concentrations in zooplankton at this location were also examined. A similar, but diphased trend between 210 Po in zooplankton and 210 Po in rain and dry fallout deposition rate was demonstrated. 210 Po concentrations in the dissolved phase of seawater tended to diminish as mean daily rainfall increased suggesting that rain inputs serve as a 210 Po dilution mechanism in seawater at this location. Copyright © 2016 Elsevier Ltd. All rights reserved.

Radioiodine therapy and thyrostatic drugs and iodine

Energy Technology Data Exchange (ETDEWEB)

Moka, D.; Dietlein, M.; Schicha, H. [Department of Nuclear Medicine, University of Cologne, Joseph Stelzmannstrasse 9, 50924 Koeln (Germany)

2002-08-01

Radioiodine therapy is now the most common definite treatment for persistent hyperthyroidism. The outcome of radioiodine therapy depends mainly on the absorbed energy dose in the diseased thyroid tissue. The administered activity and the resulting target dose in the thyroid depend on both the biokinetics of radioiodine and the actual therapeutic effect of radioiodine in the thyroid. Thyrostatic drugs have a major influence on the kinetics of radioiodine in the thyroid and may additionally have a radioprotective effect. Pre-treatment with thyrostatic medication lowers the effective half-life and uptake of radioiodine. This can reduce the target dose in the thyroid and have a negative influence on the outcome of the therapy. Discontinuation of medication shortly before radioiodine administration can increase the absorbed energy dose in the thyroid without increasing the whole-body exposure to radiation as much as would a higher or second radioiodine administration. Furthermore, administration of non-radioactive iodine-127 2-3 days after radioiodine administration can also increase the effective half-life of radioiodine in the thyroid. Thus, improving the biokinetics of radioiodine will allow lower activities to be administered with lower effective doses to the rest of the body, while achieving an equally effective target dose in the thyroid. (orig.)

Immunoscintigraphy : facts and fiction

International Nuclear Information System (INIS)

Munz, D.L.; Emrich, D.

1990-01-01

In the first part of this volume the fundamentals of immuno-scintigraphy including immunological and technological basics, radio-labelling, biokinetics, dosimetry, adverse reactions, and legislation concerning approval of radiolabelled monoclonal antibodies as radio-pharmaceuticals are dealt with. In the second part, clinical experience in using monoclonal antibodies in the most relevant oncologic and non-neoplastic diseases is presented both from a diagnostic and a therapeutic point of view. (author). refs.; figs.; tabs

Plutonium fecal and urinary excretion functions: Derivation from a systematic whole-body retention function

International Nuclear Information System (INIS)

Sun, C.; Lee, D.

1999-01-01

Liver-bile secretion directly influences the content of plutonium in feces. To assess the reliability of plutonium metabolic models and to improve the accuracy of interpreting plutonium fecal data, the authors developed a compartmental model that simulates the metabolism of plutonium in humans. With this model, they can describe the transport of plutonium contaminants in the systemic organs and tissues of the body, including fecal and urine excretions, without using elaborate kinetic information. The parameter values of the models, which describe the translocation rates and recycling of plutonium in the body, can be derived from a multi-term exponential systemic function for whole-body retention. The analytical derivations and algorithms for solving translocation parameter values are established for the model and illustrated by applying them to the biokinetics and bioassay of plutonium. This study describes how to (1) design a physiological model for incorporating liver biliary secretion and for obtaining a fecal-excretion function, (2) develop an analytical solution for identifying the translocation-parameter values incorporating the recycling of plutonium in the body, and (3) derive a set of urinary and fecal excretion-functions from a published systemic whole-body retention function, generally acknowledged to be accurate, as a real and practical example

{sup 131}I age-dependent inhalation dose in Southern Poland from Fukushima accident

Energy Technology Data Exchange (ETDEWEB)

Brudecki, K.; Szufa, K.; Mietelski, J.W. [Polish Academy of Sciences, Institute of Nuclear Physics, Krakow (Poland)

2017-03-15

A general method for calculating doses absorbed from isotopes released in nuclear accidents is presented. As an example, this method was used to calculate doses for inhabitants of Southern Poland due to inhalation of {sup 131}I released due to the Fukushima nuclear plant accident. {sup 131}I activity measurements in the air of that region provided the basis for the study. The proposed model is based on a complex biokinetic model for iodine merging the Leggett model developed in 2010 with the human respiratory tract and gastrointestinal tract models recommended by the International Commission on Radiological Protection (ICRP). This model is described here, and it is demonstrated that resulting dose estimates are consistent with those obtained using the ICRP methodology. Using the developed model, total doses were calculated for six age groups of both genders, for gaseous and aerosol fractions alike. The committed effective dose, H{sub 50}, for an adult man reached 16 nSv, which is lower than 0.001% of the background dose. The dose for the thyroid of an adult reached 0.33 μSv, which corresponds to circa 0.0007% of the dose to the population of Southern Poland after the Chernobyl nuclear plant accident. (orig.)

Comparing trace metal bioaccumulation characteristics of three freshwater decapods of the genus Macrobrachium

Energy Technology Data Exchange (ETDEWEB)

Cresswell, Tom, E-mail: tom.cresswell@ansto.gov.au [Centre for Environmental Contaminants Research, CSIRO Land and Water, New Illawarra Rd, Lucas Heights, 2234, NSW (Australia); School of Applied Sciences, RMIT University, Plenty Road, Bundoora 3083, VIC (Australia); Smith, Ross E.W. [Hydrobiology, Lang Parade, Auchenflower 4066, QLD (Australia); Nugegoda, Dayanthi [School of Applied Sciences, RMIT University, Plenty Road, Bundoora 3083, VIC (Australia); Simpson, Stuart L. [Centre for Environmental Contaminants Research, CSIRO Land and Water, New Illawarra Rd, Lucas Heights, 2234, NSW (Australia)

2014-07-01

Highlights: • Exposed three species of prawns of same genus to solid- and dissolved-phase metals. • Cd bioaccumulated from dissolved phase was significantly different between species. • All three species retained >95% of bioaccumulated Cd during the depuration phase. • Bioaccumulation of As, Pb and Zn from solid phase was different between species. • Results highlight variability among species, even under controlled conditions. - Abstract: Potential sources and kinetics of metal bioaccumulation by the three Macrobrachium prawn species M. australiense, M. rosenbergii and M. latidactylus were assessed in laboratory experiments. The prawns were exposed to two scenarios: cadmium in water only; and exposure to metal-rich mine tailings in the same water. The cadmium accumulation from the dissolved exposure during 7 days, followed by depuration in cadmium-free water for 7 days, was compared with predictions from a biokinetic model that had previously been developed for M. australiense. M. australiense and M. latidactylus accumulated significant tissue cadmium during the exposure phase, albeit with different uptake rates. All three species retained >95% of the bioaccumulated cadmium during the depuration phase, indicating very slow efflux rates. Following exposure to tailings, there were significant (p < 0.05) differences in tissue arsenic, cadmium, lead and zinc concentrations among species. Cadmium and zinc concentrations were increased relative to controls for all three species but were not different between treatments (direct/indirect contact with tailings), suggesting these metals were primarily accumulated via the dissolved phase. All species bioaccumulated significantly greater arsenic and lead when in direct contact with mine tailings, demonstrating the importance of an ingestion pathway for these metals. Copper was not bioaccumulated above control concentrations for any species. The differences between the metal accumulation of the three prawns indicated

Estimation of absorbed and effective dose in {sup 18}F-FDG em PET- CT exams for diagnosis of lung cancer; Estimativa de dose absorvida e efetiva em exames de {sup 18}F-FDG em PET- CT para diagnostico de cancer de pulmao

Energy Technology Data Exchange (ETDEWEB)

Carvalho, Guilherme Neto de Pinho; Santana, Priscila do Carmo, E-mail: guinpc1@ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Anatomia e Imagem; Oliveira, Paulo Marcio Campos de; Reis, Lucas Paixao dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2015-04-15

This paper presents an evaluation of tissues and organs absorbed doses as well as the effective dose resulting from PET-CT scans performed with {sup 18}F-FDG radiopharmaceutical for lung cancer diagnosis in whole body scans. The ICRP-106 biokinetic model was used to estimate the absorbed and effective doses from the radiopharmaceutical for both male and female patient according to the characteristics of anthropomorphic Alderson Rando® simulators. Computer Tomography doses were evaluated using thermoluminescent detectors inserted in the same anthropomorphic simulators. Optimization protocols for image acquisition and the use of automatic exposure control were used in order to reduce patient doses, taking into account the equipment model and its system. The effective dose in female patients was 5.8 mSv. The effective dose in male patients was 8.4 mSv. The dose values estimated for the {sup 18}F-FDG PET-CT scan are below the values described in the literature. This is because the CT was not used for diagnostic but for morphological mapping. (author)

The Biomechanisms of Metal and Metal-Oxide Nanoparticles’ Interactions with Cells

Directory of Open Access Journals (Sweden)

Sondra S. Teske

2015-01-01

Full Text Available Humans are increasingly exposed to nanoparticles (NPs in medicine and in industrial settings, where significant concentrations of NPs are common. However, NP interactions with and effects on biomolecules and organisms have only recently been addressed. Within we review the literature regarding proposed modes of action for metal and metal-oxide NPs, two of the most prevalent types manufactured. Iron-oxide NPs, for instance, are used as tracers for magnetic resonance imaging of oncological tumors and as vehicles for therapeutic drug delivery. Factors and theories that determine the physicochemical and biokinetic behaviors of NPs are discussed, along with the observed toxicological effects of NPs on cells. Key thermodynamic and kinetic models that explain the sources of energy transfer from NPs to biological targets are summarized, in addition to quantitative structural activity relationship (QSAR modeling efforts. Future challenges for nanotoxicological research are discussed. We conclude that NP studies based on cell culture are often inconsistent and underestimate the toxicity of NPs. Thus, the effect of NPs needs to be examined in whole animal systems.

From consumption to harvest: Environmental fate prediction of excreted ionizable trace organic chemicals

DEFF Research Database (Denmark)

Polesel, Fabio; Plósz, Benedek G.; Trapp, Stefan

2015-01-01

Excreted trace organic chemicals, e.g., pharmaceuticals and biocides, typically undergo incomplete elimination in municipal wastewater treatment plants (WWTPs) and are released to surface water via treated effluents and to agricultural soils through sludge amendment and/or irrigation with freshwa......Excreted trace organic chemicals, e.g., pharmaceuticals and biocides, typically undergo incomplete elimination in municipal wastewater treatment plants (WWTPs) and are released to surface water via treated effluents and to agricultural soils through sludge amendment and/or irrigation...... with freshwater or reclaimed wastewater. Recent research has shown the tendency for these substances to accumulate in food crops. In this study, we developed and applied a simulation tool to predict the fate of three ionizable trace chemicals (triclosan-TCS, furosemide-FUR, ciprofloxacin-CIP) from human...... and a recently developed dynamic soil-plant uptake model. The simulation tool was tested using country-specific (e.g., consumption/emission rates, precipitation and temperature) input data. A Monte Carlo-based approach was adopted to account for the uncertainty associated to physico-chemical and biokinetic model...

UK laboratory intercomparison on internal dosimetry

Energy Technology Data Exchange (ETDEWEB)

Speed, J.; Birchall, A.; Bull, R.; Cockerill, R.; Jarvis, N.S.; Marsh, J.W.; Peace, M.S.; Roberts, G.; Scarlett, C.; Spencer, D.; Stewart, P

2003-07-01

A laboratory intercomparison for internal dose assessment from a variety of intake scenarios is described. This is the first UK intercomparison using the revised ICRP Human Respiratory Tract and biokinetic models. Four United Kingdom laboratories participated and six cases were assessed. Overall, the agreement in internal dose assessments between laboratories was considered satisfactory with 79% of the assessed committed effective doses, e(50), for cases within a band of {+-}40% of the median value. The range (highest/lowest) in e(50) estimated by the laboratories was smallest (1.2) for a case involving inhalation of {sup 137}Cs. The range was greatest (6.0) for a case involving a wound with, and possible inhalation of, {sup 238}Pu, {sup 239}Pu and {sup 241}Am; the variation between laboratories in assessment of intakes could not be considered to be satisfactory in this case. Judgements on the most appropriate data to use in estimating intakes, choice of parameter values for use with the ICRP models and allowing for the effects of treatment with DTPA were important sources of variability between laboratories. (author)

Radiation protection: Scientific fundamentals, legal regulations, practical applications. Compendium. 8. ed.

International Nuclear Information System (INIS)

Buchert, G.; Czarwinski, R.; Martini, E.; Ruehle, H.; Wust, P.

2003-01-01

In 2003, radiation effects and radiation risks were again a central issue, with new biokinetic and dosimetric models. Preliminary experience with new legal regulations on radiation protection was a central issue. Dosimetry and radiation protection metrology were gone into, as was radiation exposure in medicine, engineering, and the environment. New diagnostic methods in medicine were presented, and radiation exposures resulting from some of these techniques were analyzed. Industrial applications of ionising radiation and technical radiography were presented. Nuclear engineering was covered as well, e.g. how to maintain the current know-how after the agreed nuclear phase-out, the transport of spent fuel elements, and the safety of nuclear power stations in eastern Europe. As in the years before, detection limits in radiation measurement, calculations of radiation exposure, incidents in nuclear facilities, and radiation exposure assessment after safety-relevant incidents were among the issues discussed. (orig.)

The 21st LH Gray Conference (June 4-6, 2008)

Energy Technology Data Exchange (ETDEWEB)

West, C. M. L. [Univ. of Manchester (United Kingdom); Martin, C. J. [Gartnavel Royal Hospital, Glasgow (United Kingdom); Sutton, D. G. [Ninewells Hospital and Medical School, Dundee (United Kingdom); Wright, E. G. [Ninewells Hospital and Medical School, Dundee (United Kingdom)

2009-01-12

The 21st LH Gray Conference, organised by the LH Gray Trust with the Society for Radiological Protection, brought together international experts in radiobiology, epidemiology and risk assessment, and scientists involved in diagnostic and therapeutic radiation exposure. The meeting - held in Edinburgh, Scotland 4-6 June 2008 - aimed to raise awareness, educate and share knowledge of important issues in radiation protection. A distinguished group of speakers discussed topics which included: non-targeted effects of radiation, exposure to high natural background radiation, non-cancer effects in Japanese bomb survivors, lessons learnt from Chernobyl, radiation in the workplace, biokinetic modelling, uncertainties in risk estimation, issues in diagnostic medical exposures, lessons leant from the polonium-210 incidence and how the radiobiology-radiation oncology community is needed to help society prepare for potential future acts of radiation terrorism. The conference highlighted the importance, relevance and topicality of radiobiology today.

Reference values for total blood volume and cardiac output in humans

Energy Technology Data Exchange (ETDEWEB)

Williams, L.R. [Indiana Univ., South Bend, IN (United States). Division of Liberal Arts and Sciences

1994-09-01

Much research has been devoted to measurement of total blood volume (TBV) and cardiac output (CO) in humans but not enough effort has been devoted to collection and reduction of results for the purpose of deriving typical or {open_quotes}reference{close_quotes} values. Identification of normal values for TBV and CO is needed not only for clinical evaluations but also for the development of biokinetic models for ultra-short-lived radionuclides used in nuclear medicine (Leggett and Williams 1989). The purpose of this report is to offer reference values for TBV and CO, along with estimates of the associated uncertainties that arise from intra- and inter-subject variation, errors in measurement techniques, and other sources. Reference values are derived for basal supine CO and TBV in reference adult humans, and differences associated with age, sex, body size, body position, exercise, and other circumstances are discussed.

A case of internal contamination by 90Sr of a member of public

International Nuclear Information System (INIS)

Malatova, I.; Cespirova, I.; Drabova, D.; Beckova, V.

1998-01-01

A case of internal contamination by 90 Sr of a member of the public is described. An unauthorised person entered a low-activity waste storage placed in an abandoned sand mine, a barrel with marker for radioactive substances was found and manipulated with a tin labelled as ISOMET Sr90. The radiation protection authority was informed after 6 days and found surface contamination on his belongings. Whole-body counting with an HPGe detector and excretion analysis were performed. He was measured by whole-body counter 16 times from November 1990 to August 1992, 9 samples of urine and 6 samples of faeces were collected. For the estimation of the dose, the software CINDY with the biokinetic models of ICRP 30 was used. Single and continuous intakes were assumed. Intake was estimated to be about 3 MBq and committed effective dose 84 mSv. (author)

Internal Dosimetry for Inhalation of Hafnium Tritide Aerosols

Energy Technology Data Exchange (ETDEWEB)

Inkret, W.C.T.; Schillaci, M.E.; Boyce, M.K.; Cheng, Y.S.; Efurd, D.W.; Little, T.T.; Miller, G.; Musgrave, J.A.; Wermer, J.R

2001-07-01

Metal tritides with low dissolution rates may have residence times in the lungs which are considerably longer than the biological half-time normally associated with tritium in body water, resulting in long-term irradiation of the lungs by low energy {beta} particles and bremsstrahlung X rays. Samples of hafnium tritide were placed in a lung simulant fluid to determine approximate lung dissolution rates. Hafnium hydride samples were analysed for particle size distribution with a scanning electron microscope. Lung simulant data indicated a biological dissolution half-time for hafnium tritide on the order of 10{sup 5}d. Hafnium hydride particle sizes ranged between 2 and 10 {mu}m, corresponding to activity median aerodynamic diameters of 5 to 25 {mu}m. Review of in vitro dissolution data, development of a biokinetic model, and determination of secondary limits for 1 {mu}m AMAD particles are presented and discussed. (author)

Tropical radioecology

CERN Document Server

Baxter, M

2012-01-01

Tropical Radioecology is a guide to the wide range of scientific practices and principles of this multidisciplinary field. It brings together past and present studies in the tropical and sub-tropical areas of the planet, highlighting the unique aspects of tropical systems. Until recently, radioecological models for tropical environments have depended upon data derived from temperate environments, despite the differences of these regions in terms of biota and abiotic conditions. Since radioactivity can be used to trace environmental processes in humans and other biota, this book offers examples of studies in which radiotracers have been used to assess biokinetics in tropical biota. Features chapters, co-authored by world experts, that explain the origins, inputs, distribution, behaviour, and consequences of radioactivity in tropical and subtropical systems. Provides comprehensive lists of relevant data and identifies current knowledge gaps to allow for targeted radioecological research in the future. Integrate...

Guidance for the assessment of a chronic intake of workers in a nuclear fuel facility in Argentina

International Nuclear Information System (INIS)

Rojo, A.M.; Spinella, M.R.; Gomez Parada, I.

2006-01-01

Todays trend for the design of internal dose monitoring programmes of workers applying the ICRP respiratory tract model requires taking into account the specific absorption parameters of the compounds and the physical data of the workplace aerosols. The aim of this analysis is to determine the specific ALIs and to establish reference levels for the assessment of chronic intake of workers, using the data from individual monitoring (pulmonary burden and urinary and fecal excretion) for natural uranium and uranium with 3.5 % and 20 % enrichment. In this paper the I.M.B.A. and AIDE software were used applying the respiratory tract model and the uranium biokinetic model published by ICRP taking into consideration the specific parameters of the uranium compounds. On the basis of this analysis, the relevance of lung, urine and faeces measurements in the individual monitoring of workers for internal dosimetry purposes is discussed It is concluded that these monitoring methods are useful for confirming that ALIs have not been exceeded and to assure that daily intakes are below the toxicological limits (2 mg/d) but it is necessary considering practical limitations of each method. (authors)

Biokinetics and dosimetry in patients of {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesin: images of GRP receptors; Biocinetica y dosimetria en humanos de {sup 99m}Tc-HYNIC-Lys{sup 3}-Bombesina: imagenes de receptores GRP

Energy Technology Data Exchange (ETDEWEB)

Santos C, C L [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

2007-07-01

The bombesin (BN) receptor subtype 2 (GRP-r) is expressed in several normal human tissues and is over-expressed in various human tumors including breast, prostate, small cell lung and pancreatic cancer. Recently [{sup 99m}Tc]EDDA/HYNIC-Lys{sup 3}-bombesin ({sup 99m}Tc-HYNIC-BN) was reported as a radiopharmaceutical with high stability in human serum, specific cell GRP-r binding and rapid cell internalization. The aim of this study was to evaluate the feasibility of using {sup 99m}Tc-HYNIC-BN to image GRP-r and to assess the radiopharmaceutical biokinetics and dosimetry in 4 breast cancer patients and in 7 healthy women. Methods: Whole-body images were acquired at 20, 90, 180 min and 24 h after {sup 99m}Tc-HYNIC-BN administration. Regions of interest (ROIs) were drawn around source organs on each time frame. The same set of ROIs was used for all 11 scans and the cpm of each ROI was converted to activity using the conjugate view counting method. The image sequence was used to extrapolate {sup 99m}Tc-HYNIC-BN time-activity curves in each organ in order to calculate the total number of disintegrations (N) that occurred in the source regions, according with MIRD methodology. N data were the input for the OLINDA/EXM code to calculate internal radiation dose estimates. Results: Images showed a rapid radiopharmaceutical blood clearance with renal excretion as predominant route. {sup 99m}Tc-HYNIC-BN exhibited high in vivo affinity for GRP-r over-expression successfully visualized in cancer mammary glands and well differentiated from the ubiquitous GRP-r expression in normal breast, lungs and airways. There was no statistically significant difference (p > 0.05) in the radiation absorbed doses between cancer patients and healthy women. The average equivalent doses (n=11) for a study using 740 MBq were 24.8 +- 8.8 mSv (kidneys), 7.3 +- 1.8 mSv (lungs), 6.5 +- 4.0 mSv (breast) 2.0 +- 0.3 mSv (pancreas), 1.6 +- 0.3 mSv (liver), 1.2 +- 0.2 mSv (ovaries) and 1.0 +- 0.2 mSv (red

Nitrification biokinetics in rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Tatari, Karolina

Danmarks drikkevandsforsyning er udelukkende baseret på grundvand – og mere end 2500 vandværker behandler hver dag vand til de danske forbrugere. Selv om denne vandbehandling betegnes som simpel, er den i virkeligheden baseret på komplicerede mikrobielle processer, som vi hidtil har vidst relativ...

Bibliographic study on molybdenum biokinetics. Literaturstudie zur Biokinetik von Molybdaen

Energy Technology Data Exchange (ETDEWEB)

Erzberger, A.

1988-05-01

This bibliographical study compiles and analyzes findings about the metabolism and resorption of molybdenum. Besides including studies on the physiology of molybdenum 99, a general survey is given on molybdenum in the environment and on its physiological behaviour. In particular, information on the dependence of molybdenum resorption on various factors, such as the chemical form, antagonisms etc., are gathered from literature. These factors have to be considered for sensibly carrying out necessary experiments.

United States Transuranium and Uranium Registries: Researching radiation protection. USTUR annual report for February 1, 1999 through January 31, 2000

International Nuclear Information System (INIS)

Ehrhart, Susan M.; Filipy, Ronald E.

2000-01-01

The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report covers USTUR activities during the year from February 1999 through January 2000

United States Transuranium and Uranium Registries. Annual report October 1, 1994 - September 30, 1995

Energy Technology Data Exchange (ETDEWEB)

Kathren, R.L.; Harwick, L.A.; Markel, M.J.

1996-07-01

The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report covers USTUR activities during the year from October 1994 through September 1995.

United States Transuranium and Uranium Registries. Annual report February 1, 2000--January 31, 2001

Energy Technology Data Exchange (ETDEWEB)

Ehrhart, Susan M. (ed.); Filipy, Ronald E. (ed.)

2001-07-01

The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report covers USTUR activities during the year from February 2000 through January 2001.

United States Transuranium and Uranium Registries: Researching radiation protection. USTUR annual report for February 1, 1999 through January 31, 2000

Energy Technology Data Exchange (ETDEWEB)

Ehrhart, Susan M. (ed.); Filipy, Ronald E. (ed.)

2000-07-01

The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report covers USTUR activities during the year from February 1999 through January 2000.

United States Transuranium and Uranium Registries. Annual report February 1, 2000-January 31, 2001

International Nuclear Information System (INIS)

Ehrhart, Susan M.; Filipy, Ronald E.

2001-01-01

The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report covers USTUR activities during the year from February 2000 through January 2001

Optimization of internal monitoring methodology of {sup 18}F in the form of {sup 18}FDG at the CRCN-NE, Recife, Pernambuco, Brazil; Otimizacao da metodologia de monitoracao interna de {sup 18}F na forma de {sup 18}FDG no CRCN-NE

Energy Technology Data Exchange (ETDEWEB)

Lacerda, Isabelle V.B.; Xavier, Aline C.S.; Lima, Fabiana F.; Oliveira, Mercia L., E-mail: fflima@cnen.gov.b, E-mail: mercial@cnen.gov.b, E-mail: falima@cnen.gov.b [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Oliveira, Cassio M., E-mail: cmo@cdtn.b [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Silva, Tania V. da; Alonso, Thessa C.; Silva, Teogenes A. da, E-mail: silvatv@cdtn.b, E-mail: alonso@cdtn.b, E-mail: silvata@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), Belo Horizonte, MG (Brazil)

2011-07-01

The work aims to optimize and improve the efficiency of the internal monitoring technique developed at Centro Regional de Ciencias Nucleares do Nordeste for F-18 in form of F-18DG radiopharmaceuticals. It was performed two assays for the methodology developed. The first was performed in a makeshift room, while the second was performed in a room with walls reinforced with concrete. The detection system was a NaI (Tl) 3{sup x} 3{sup s}cintillation detector, coupled with the software Genie 2000. In order to obtain the calibration factor, a brain phantom containing {sup 22}Na liquid source was measured. The interpretation of the bioassay data was performed using the biokinetic models provided by the ICRP 53 and edited by software AIDE-version 6, which gives the fraction of activity retained in the organs as a function of time. The sensitivities of detection were similar, resulting in a minimum detectable dose below 1 mSv, as recommended by the IAEA. (author)

Dose calculations for intakes of ore dust

International Nuclear Information System (INIS)

O'Brien, R.S.

1998-08-01

This report describes a methodology for calculating the committed effective dose for mixtures of radionuclides, such as those which occur in natural radioactive ores and dusts. The formulae are derived from first principles, with the use of reasonable assumptions concerning the nature and behaviour of the radionuclide mixtures. The calculations are complicated because these 'ores' contain a range of particle sizes, have different degrees of solubility in blood and other body fluids, and also have different biokinetic clearance characteristics from the organs and tissues in the body. The naturally occurring radionuclides also tend to occur in series, i.e. one is produced by the radioactive decay of another 'parent' radionuclide. The formulae derived here can be used, in conjunction with a model such as LUDEP, for calculating total dose resulting from inhalation and/or ingestion of a mixture of radionuclides, and also for deriving annual limits on intake and derived air concentrations for these mixtures

Radiation dose to the pediatric population of Slovak Republic from diagnostic nuclear medicine procedures

International Nuclear Information System (INIS)

Ftacnikova, S.; Fueriova, A.

1996-01-01

The increased number of in vitro diagnostic nuclear medicine examinations has created the need for more precise determination of radiation dose to the population, specially to the children. A questionnaire survey has been performed on all nuclear medicine facilities in Slovak Republic through 1982 to 1994 with a special attention to pediatric patients in 1994. The information obtained was about the age distribution, number of different types of examinations, radiopharmaceuticals used and the value of mean administered radioactivity per exam. These data were used to evaluate the mean effective dose per exam and per capita, the collective effective dose for special type of examinations, for different radiopharmaceuticals and for radionuclides used in diagnostic procedures. In calculations we used the best available biokinetic models of the distribution of radiopharmaceuticals in organs as a function of age. The results show that the Slovak Republic appeared favorable in comparison to other countries in the judicious use of diagnostic nuclear medicine procedures performed on pediatric population. (author)

Code for Internal Dosimetry (CINDY)

International Nuclear Information System (INIS)

Strenge, D.L.; Peloquin, R.A.; Sula, M.J.; Johnson, J.R.

1990-10-01

The CINDY (Code for Internal Dosimetry) Software Package has been developed by Pacific Northwest Laboratory to address the Department of Energy (DOE) Order 5480.11 by providing the capabilities to calculate organ dose equivalents and effective dose equivalents using the approach of International Commission on Radiological Protection (ICRP) 30. The code assist in the interpretation of bioassay data, evaluates committed and calendar-year doses from intake or bioassay measurement data, provides output consistent with revised DOE orders, is easy to use, and is generally applicable to DOE sites. Flexible biokinetics models are used to determine organ doses for annual, 50-year, calendar-year, or any other time-point dose necessary for chronic or acute intakes. CINDY is an interactive program that prompts the user to describe the cases to be analyzed and calculates the necessary results for the type of analysis being performed. Four types of analyses may be specified. 92 figs., 10 tabs

Biodegradation of naphthalene from nonaqueous-phase liquids

International Nuclear Information System (INIS)

Ghoshal, S.; Luthy, R.G.; Ramaswami, A.

1995-01-01

Dissolution of polycyclic aromatic hydrocarbons (PAHs) from a non-aqueous-phase liquid (NAPL) to the aqueous phase renders these compounds bioavailable to microorganisms. Subsequent biodegradation of organic phase PAH then results in a depletion of PAH from the NAPL. This study focuses on identifying the rate-controlling processes affecting naphthalene biomineralization from a complex multicomponent NAPL, coal tar, and a simple two-component NAPL. A simplified dissolution degradation model is presented to identify quantitative criteria to assess whether mass transfer or biokinetic limitations control the overall rate of biotransformation of PAH compounds. Results show that the rate of mass transfer may control the overall rate of biotransformation in certain systems. Mass transfer does not limit biodegradation in slurry systems when coal tar is distributed in the micropores of a large number of small microporous silica particles. The end points of naphthalene degradation from the NAPLs have been evaluated, and results suggest that depletion of a significant mass of naphthalene from the NAPL phase is possible

Indirect monitoring of internal exposure for actinides

Energy Technology Data Exchange (ETDEWEB)

Carneiro G, C.J.; Barreto F, J.; Todo A, A. [Instituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN, Av. Professor Lineu Prestes No. 2242, Zip code 05508-000, Sao Paulo (Brazil)

2006-07-01

The procedure used to the assessment of internal exposure of workers involved with dismantling lightning rods and radioactive smoke detectors is described. Due to the presence of the sources of {sup 241} Am in these devices, a monitoring program to the workers have been implemented. This paper presents an analytical method for the separation and analysis of plutonium (Pu) and americium (Am) in urine samples using solid-phase extraction chromatography and alpha spectrometry. The mean recovery obtained with this technique is about 80% and the detection limit for 24 h urine sample range between 0.6 mBqL{sup -1} and 1.0 mBqL{sup -1}. The assessment of intakes and internal doses are performed following ICRP Publication 78 recommendations and appropriated biokinetic models (ICRP, 1997). Assumptions have been made for routine monitoring of these workers and it is also discussed the establishment of the internal monitoring program using the results of alpha measurements. (Author)

Estimation of cross talk between lungs and liver for 241Am using phoswich detector

International Nuclear Information System (INIS)

Mishra, Lokpati; Nadar, Minal Y.; Singh, I.S.; Sawant, P.D.

2018-01-01

241 Am is used as a tracer for in-vivo assessment of plutonium (Pu) in the lungs. Internal contamination of 241 Am is estimated by measuring its 59.5 keV photons then activity of Pu is estimated by applying Pu/ 241 Am ratio obtained from radiochemical analysis of fecal/workplace sample. According to ICRP systemic bio-kinetic model, for Type M compounds of 241 Am after 100 days post inhalation intake, 241 Am activity in liver exceeds 241 Am activity present in the lungs and goes on increasing even up to about ten years. In this work, cross talk (CT) between lungs and liver viz. CT (liver to lungs) and CT (lungs to liver) for the actinide monitoring system for 241 Am using realistic thorax Lawrence Livermore National Laboratory (LLNL) phantom were estimated. Also CT has been estimated using voxel phantom by carrying out Monte Carlo simulations in FLUKA code. This study will help in reporting the actual activity present in the individual organ (lungs, liver)

Optimization of internal monitoring methodology of 18F in the form of 18FDG at the CRCN-NE, Recife, Pernambuco, Brazil

International Nuclear Information System (INIS)

Lacerda, Isabelle V.B.; Xavier, Aline C.S.; Lima, Fabiana F.; Oliveira, Mercia L.; Oliveira, Cassio M.; Silva, Tania V. da; Alonso, Thessa C.; Silva, Teogenes A. da

2011-01-01

The work aims to optimize and improve the efficiency of the internal monitoring technique developed at Centro Regional de Ciencias Nucleares do Nordeste for F-18 in form of F-18DG radiopharmaceuticals. It was performed two assays for the methodology developed. The first was performed in a makeshift room, while the second was performed in a room with walls reinforced with concrete. The detection system was a NaI (Tl) 3 x 3 s cintillation detector, coupled with the software Genie 2000. In order to obtain the calibration factor, a brain phantom containing 22 Na liquid source was measured. The interpretation of the bioassay data was performed using the biokinetic models provided by the ICRP 53 and edited by software AIDE-version 6, which gives the fraction of activity retained in the organs as a function of time. The sensitivities of detection were similar, resulting in a minimum detectable dose below 1 mSv, as recommended by the IAEA. (author)

Preliminary study of internal monitoring of the occupational exposed individuals to the 18FDG at the C RCN-Ne, Recipe, Pernambuco, Brazil

International Nuclear Information System (INIS)

Oliveira, Cassio M.; Lacerda, Isabelle V.B.; Lima, Fabiana F.; Oliveira, Mercia L.; Silva, Tania V. da; Alonso, Thessa C.; Silva, Teogenes A. da

2011-01-01

This work aims to develop and establish a methodology for in vivo internal monitoring at individuals occupationally exposed (IOE) to F-18 in form of F-18DG at the DIPRA/CRCN-NE. The detection system used was the NaI(Tl) 3' x 3', coupled with the software Genie 2000. The measurements performed with the brain phantom were used to obtain the Calibration Factor. The bioassay data interpretation was performed through software AIDE, using the F-18DG biokinetic model available in ICRP 53 publication. The MDED obtained was compared to the value of the recording level, 1 mSv, recommended by IAEA in order to validate the technique. During two days of F-18DG productions, there were performed in vivo measurements of the IOE at DIPRA/CRCN-NE. The methodology developed demonstrated sufficient sensitivity for detect MDED of 76 n Sv. The results of the in vivo measurements demonstrated that all IOE from CRCN/NE obtained doses below MDED. (author)

Mineral water 222 Rn activity decrease due to consumption habits

International Nuclear Information System (INIS)

Cipriani, Moacir; Taddei, Maria Helena Tirollo; Silva, Nivaldo Carlos da

2001-01-01

Mineral waters from the Pocos de Caldas Plateau springs, an elevated region with high natural radioactivity, in the State of Minas Gerais, Brazil, have significant 222 Rn concentration on site. The highest concentration in the waters are from: Fonte Villela - Aguas da Prata (∼ 1000 Bql -1 ); Fonte Grande Hotel - Pocinhos do Rio Verde (∼ 400 Brq -1 ) and Fonte CNEN Lab - Pocos de Caldas (∼ 290 Bql -1 ). These waters are used by the population as drinking water and due to consumption habits, can lead to internal doses above accepted limits for the public. This work deals with the decrease of 222 Rn activity in mineral waters fro two different popular consumption habits, and with the adult effective dose equivalent reduction due to water consumption habits. It has been found that the estimated dose based on the biokinetic Crawford-Brown model, can be one fourth of dose based on 222 Rn activity on site. (author)

The Mayak Worker Dosimetry System (MWDS-2013): determination of the individual scenario of inhaled plutonium intake in the Mayak workers

International Nuclear Information System (INIS)

Sokolova, A. B.; Efimov, A. V.; Vostrotin, V. V.; Birchall, A.; Dorrian, M.-D.

2017-01-01

In order to estimate doses of workers exposed to plutonium, it is necessary to make assumptions about both the route and the time course of intake. The objective of this study was to determine a time course for the inhalation rate for plutonium (intake regime) useful for biokinetic modeling. Records from workplace air sampling, personnel biophysical examinations and autopsy data from former Mayak Production Association (MPA) workers were used. Plutonium accumulation strongly correlated with the volumetric activity of plutonium in workplace air. Using data from activity in air at MPA workplaces over time, a three-step function of intake was adopted. The adequacy of this three-step function was tested by comparing predicted doses using more complicated intake regimes. Uncertainties on the three-step function were also characterized based on air sampling data. The three-step function was assumed to be common to all workers, but an individual intake regime for each worker was calculated by convoluting it with the worker's actual employment history. (authors)

Indirect monitoring of internal exposure for actinides

International Nuclear Information System (INIS)

Carneiro G, C.J.; Barreto F, J.; Todo A, A.

2006-01-01

The procedure used to the assessment of internal exposure of workers involved with dismantling lightning rods and radioactive smoke detectors is described. Due to the presence of the sources of 241 Am in these devices, a monitoring program to the workers have been implemented. This paper presents an analytical method for the separation and analysis of plutonium (Pu) and americium (Am) in urine samples using solid-phase extraction chromatography and alpha spectrometry. The mean recovery obtained with this technique is about 80% and the detection limit for 24 h urine sample range between 0.6 mBqL -1 and 1.0 mBqL -1 . The assessment of intakes and internal doses are performed following ICRP Publication 78 recommendations and appropriated biokinetic models (ICRP, 1997). Assumptions have been made for routine monitoring of these workers and it is also discussed the establishment of the internal monitoring program using the results of alpha measurements. (Author)

Revised dose limits and new respiratory tract model and their implications for annual limits of intake of radioactive materials - A review of recent ICRP publications

International Nuclear Information System (INIS)

Schlesinger, T.; Silverman, I.; Shapira, M.

1996-01-01

Ionizing radiation may cause immediate and/or delayed biological damages to the body of the exposed person and/or his/her progeny. The exposure may be caused by an external source or may arise due to internal contamination by a radioactive material. In order to prevent such exposure, or to reduce the probability that it will occur, national authorities and international organizations that are engaged in radiation safety and protection have set limits for the exposure to ionizing radiation from either source. The sensitivity of the body to ionizing radiation usually decreases with age. For this reason and due to the limited possibilities to control the exposure of the general public, different limits have been set for for occupational exposure and for the exposure of members of the public of different age groups. The general principles of these limits and guidelines for their calculations are set by the International Commission on Radiological Protection (ICRP) and published in the Annals of the ICRP. The basic philosophy of the Commission, which includes the principles of justification, optimization and dose limits, the basic radiobiological models, and the distinction between stochastic and non-stochastic effects has been presented in its publication no. 26 . Based on this philosophy, the Commission issued between 1979 and 1988 a series of publications followed by annexes and addenda known as publication no. 30 . This series presented models describing the metabolism of radioactive materials which enter the body by inhalation and ingestion, the transfer of such materials from the respiratory tract and the gastrointestinal tract to the blood, and from there to the body organs and the excretion of the material from the body. This series presented also values for biokinetic parameters of these systems and transfer paths, and methods for calculating limits on intake which ensure that the exposure from internal contamination will not exceed the dose limits set by the

Experimental studies on the biokinetics of Cs-134 and Cd-109 in the blood cockle (Anadara granosa)

International Nuclear Information System (INIS)

Norfaizal Mohamed; Nita Salina Abu Bakar; Zal Uyun Wan Mahmood; Nur Hidaya Dmuliany Mohd Sidek; Zaharudin Ahmad

2010-01-01

Bioaccumulation and depuration study under controlled laboratory conditions of Cs and Cd in Anadara granosa collected at coastal Kapar, Selangor was carried out using respective radiotracer, Cs-134 and Cd-109. The radioactivity of Cs-134 and Cd-109 were determined using high resolution hyper germanium detector. Our results demonstrate that Cd-109 was accumulated efficiently by this species, except Cs-134. The steady state concentration factor (CF) for accumulation of Cs-134 and Cd-109 from seawater was estimated to be about 5.86 and 51.31, respectively. For the depuration stage, loss kinetics of Cs-134 and Cd-109 was best described by 2-compartment exponential model. Results shown that A. granosa exposed to Cs-134 have a total loss of 69% in compared to 19 % of Cd-109. Results gained in this experiment are a baseline data to evaluate future released of radioactive material from nuclear power programme facilities within this region. (author)

Bioadsorber efficiency, design, and performance forecasting for alachlor removal.

Science.gov (United States)

Badriyha, Badri N; Ravindran, Varadarajan; Den, Walter; Pirbazari, Massoud

2003-10-01

This study discusses a mathematical modeling and design protocol for bioactive granular activated carbon (GAC) adsorbers employed for purification of drinking water contaminated by chlorinated pesticides, exemplified by alachlor. A thin biofilm model is discussed that incorporates the following phenomenological aspects: film transfer from the bulk fluid to the adsorbent particles, diffusion through the biofilm immobilized on adsorbent surface, adsorption of the contaminant into the adsorbent particle. The modeling approach involved independent laboratory-scale experiments to determine the model input parameters. These experiments included adsorption isotherm studies, adsorption rate studies, and biokinetic studies. Bioactive expanded-bed adsorber experiments were conducted to obtain realistic experimental data for determining the ability of the model for predicting adsorber dynamics under different operating conditions. The model equations were solved using a computationally efficient hybrid numerical technique combining orthogonal collocation and finite difference methods. The model provided accurate predictions of adsorber dynamics for bioactive and non-bioactive scenarios. Sensitivity analyses demonstrated the significance of various model parameters, and focussed on enhancement in certain key parameters to improve the overall process efficiency. Scale-up simulation studies for bioactive and non-bioactive adsorbers provided comparisons between their performances, and illustrated the advantages of bioregeneration for enhancing their effective service life spans. Isolation of microbial species revealed that fungal strains were more efficient than bacterial strains in metabolizing alachlor. Microbial degradation pathways for alachlor were proposed and confirmed by the detection of biotransformation metabolites and byproducts using gas chromatography/mass spectrometry.

Assessing the stability of soil organic matter by fractionation and 13C isotope techniques

Science.gov (United States)

Larionova, A. A.; Zolotareva, B. N.; Kvitkina, A. K.; Evdokimov, I. V.; Bykhovets, S. S.; Stulin, A. F.; Kuzyakov, Ya. V.; Kudeyarov, V. N.

2015-02-01

Carbon pools of different stabilities have been separated from the soil organic matter of agrochernozem and agrogray soil samples. The work has been based on the studies of the natural abundance of the carbon isotope composition by C3-C4 transition using the biokinetic, size-density, and chemical fractionation (6 M HCl hydrolysis) methods. The most stable pools with the minimum content of new carbon have been identified by particle-size and chemical fractionation. The content of carbon in the fine fractions has been found to be close to that in the nonhydrolyzable residue. This pool makes up 65 and 48% of Corg in the agrochernozems and agrogray soils, respectively. The combination of the biokinetic approach with particle-size fractionation or 6 M HCl hydrolysis has allowed assessing the size of the medium-stable organic carbon pool with a turnover time of several years to several decades. The organic matter pool with this turnover rate is usually identified from the variation in the 13C abundance by C3-C4 transition. In the agrochernozems and agrogray soils, the medium-stable carbon pool makes up 35 and 46% of Corg, respectively. The isotope indication may be replaced by a nonisotope method to significantly expand the study of the inert and mediumstable organic matter pools in the geographical aspect, but this requires a comparative analysis of particle-size and chemical fractionation data for all Russian soils.

The utility of in vitro solubility testing in assessment of uranium exposure

International Nuclear Information System (INIS)

Eidson, A.F.; Damon, E.G.; Hahn, F.F.; Griffith, W.C. Jr.

1989-01-01

Assessment of accidental exposures in the uranium industry requires estimation of retention and excretion rates using bioassay measurements. This task is difficult if the solubility of the inhaled uranium compound is unknown. In our research, Beagle dogs were exposed to aerosols of commercial uranium milling products containing either pure ammonium diuranate (ADU) or U 3 0 8 . Dogs were exposed to ADU aerosols to achieve a median retained body burden of 0.058 mg U per kg body weight, or to U 3 0 8 aerosols to achieve a median retained body burden of 0.28 mg U per kg. A biokinetic model was applied to simulate retention and excretion of the two forms of uranium in vivo. Comparison of published in vitro dissolution data and modelling results with information from accidental human exposures showed that in vitro dissolution studies are necessary to characterise the differential solubilities of uranium compounds, and indicate the potential for kidney toxicity. Because variability in pulmonary clearance and urinary excretion rates is high among individual people, in vitro dissolution results are only marginally useful for estimating urinary excretion rates. (author)

Technical basis for the internal dosimetry program at the Y-12 Plant

International Nuclear Information System (INIS)

Ashley, J.C.; Barber, J.M.; Snapp, L.M.; Turner, J.E.

1992-01-01

Since the beginning of plant operations. almost all work with radioactive materials has involved isotopes associated with uranium, enriched or depleted in U 235 . While limited quantities of isotopes of elements other than uranium are present, workplace monitoring and precess knowledge have established that internal exposure from these other isotopes is insignificant in comparison with uranium. While the changing plant mission may necessitate the consideration of internal exposure from other isotopes at some point in time, only enriched and depleted uranium will be considered in this basis document. The portions of the internal dosimetry technical basis which may be unique to the Y-12 Plant is considered in this manual. This manual presents the technical basis of the routine in vivo and in vitro bioassay programs including choice of frequency, participant selection criteria, and action level guidelines. Protocols for special bioassay will be presented in the chapters which described the basis for intake, uptake, and dam assessment. A discussion of the factors which led to the need to develop a special biokinetic model for uranium at the Y-12 Plant, as well as a description of the model's basic parameters, are included in this document

Bioavailability assessment of the lipophilic benfotiamine as compared to a water-soluble thiamin derivative.

Science.gov (United States)

Bitsch, R; Wolf, M; Möller, J; Heuzeroth, L; Grüneklee, D

1991-01-01

The bioequivalence of thiamin in 2 therapeutically used preparations was tested in 10 healthy young men. Thiamin was orally administered either as lipophilic benfotiamine or as water-soluble thiamin mononitrate. Biokinetic data, measured as area under the curve and maximal concentration in plasma and hemolysate after ingestion, demonstrated a significantly improved bioavailability from the lipophilic derivative despite an ingested dose of only 40% as compared with the water-soluble salt. A superior cellular efficacy of benfotiamine was also concluded from the short-term stimulation of the thiamin-dependent transketolase activity in erythrocytes.

Effect of the kinetics of ammonium and nitrite oxidation on nitritation success or failure for different biofilm reactor geometries

DEFF Research Database (Denmark)

Lackner, Susanne; Smets, Barth F.

2012-01-01

was on the influence of key biokinetic parameters (maximum specific growth rates, oxygen and nitrogen affinity constants of AOB (ammonium oxidizing bacteria) and NOB (nitrite oxidizing bacteria)) and their ratios on nitritation efficiency in these geometries. This exhaustive simulation study revealed that nitritation...... strongly depends on the chosen kinetic parameters of AOB and NOB. The maximum specific growth rates (μmax,AOB and μmax,NOB) had the strongest impact on nitritation efficiency (NE). In comparison, the counter-diffusion geometry yielded more parameter combinations (27.5%) that resulted in high NE than the co...

Comparison of Four Types of Membrane Bioreactor Systems in Terms of Shear Stress over the Membrane Surface using Computational Fluid Dynamics

DEFF Research Database (Denmark)

Ratkovich, Nicolas Rios; Bentzen, Thomas Ruby

2013-01-01

Membrane bioreactors (MBRs) have been used successfully in biological wastewater treatment to solve the perennial problem of effective solids–liquid separation. A common problem with MBR systems is clogging of the modules and fouling of the membrane, resulting in frequent cleaning and replacement...... and requires knowledge of the membrane fouling, hydrodynamics and biokinetics. Modern tools such as computational fluid dynamics (CFD) can be used to diagnose and understand the two-phase flow in an MBR. Four cases of different MBR configurations are presented in this work, using CFD as a tool to develop...

Evaluation of absorbed dosis during studies of renal function due AI 123I / 131I (Hippuran) and 111 In (DPTA)

International Nuclear Information System (INIS)

Arteaga, Marcial V.V.; Diestra, Carlos E.C.; Villanueva, Raul A.S.; Alegria, Roberto R.; Salvatierra, Carlos C.; Rosales, Jorge M.; Gonzalez, Denis A.; Cruz, Carlos A.M.

2014-01-01

Using the MIRD methodology and Cristy-Eckerman representation for for adult kidneys, it proves that the dosimetric contributions of bodies of the biokinetics of 123 I / 131 I (Hippuran) and 111 In (DTPA) are significant, in the estimated of dose, during studies of renal function. Dosimetric contributions (whole body and urinary bladder, kidney excluding) are given by 11.90% (for 123 I), 4.97% (for 131 I) and 28.32% (for 111 In). In all cases, the dosimetric contributions are mainly due to photons emitted by the entire body

Evaluation of absorbed dosis during studies of renal function due AI {sup 123}I / {sup 131}I (Hippuran) and {sup 111} In (DPTA); Evaluacion de la dosis absorbida durante estudios de la funcion renal debido AI I{sup 123} / I{sup 131} (Hippuran) E In{sup 111} (DPTA)

Energy Technology Data Exchange (ETDEWEB)

Arteaga, Marcial V.V.; Diestra, Carlos E.C.; Villanueva, Raul A.S.; Alegria, Roberto R.; Salvatierra, Carlos C.; Rosales, Jorge M.; Gonzalez, Denis A.; Cruz, Carlos A.M., E-mail: marvva@hotmail.com [Universidad Nacional de Trujillo (UNT), Trujillo (Peru). Fisica Medica; Rios, Edulfo E.D., E-mail: ediaz@ufrgs.br [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil)

2014-07-01

Using the MIRD methodology and Cristy-Eckerman representation for for adult kidneys, it proves that the dosimetric contributions of bodies of the biokinetics of {sup 123} I / {sup 131}I (Hippuran) and {sup 111}In (DTPA) are significant, in the estimated of dose, during studies of renal function. Dosimetric contributions (whole body and urinary bladder, kidney excluding) are given by 11.90% (for {sup 123}I), 4.97% (for {sup 131}I) and 28.32% (for {sup 111} In). In all cases, the dosimetric contributions are mainly due to photons emitted by the entire body.

Biokinetics of indium-111 labeled platelets after cryotherapy of hepatic metastases

International Nuclear Information System (INIS)

Alexander, C.; Kirsch, C.-M.; Pistorius, G.; Feifel, G.

2002-01-01

Full text: The present investigation was performed to evaluate mean platelet live-span and the proportion of platelet disposal in different organs in patients after hepatic cryotherapy. Seven patients with advanced colorectal cancer and liver metastases were included. Directly before the surgical procedure a blood specimen was drawn and an in vitro labeling of patients platelets with 18 MBq Indium-111 oxime was performed. Reinjection was done intraoperatively just before cryotherapy. Blood specimen were drawn at 1, 2, 3, 24 und 48 h p.i.. Whole-body scintigraphy was acquired on day two alter operation. The evaluation comprised the calculation of mean platelet live-span and of organ activities as percentage of whole-body activity. The local disposal of platelets at the site of cryotherapy ranged from 0 to 35.2 percent, the mean value was 16,2 ± 12,2 percent (mean ± SD). The mean half-time of time-activity curve gave 0.6 to 2.4 days (mean ± SD: 1.6 ± 0.6 d; normal value: 3.5-6 d), the mean platelet life-span was between 2.1 and 5.2 days corresponding to a mean value of 3.4 ± 1.0 days (normal value: 7-11 d). The evaluation of SPECT slices of large liver metastases demonstrated that platelet disposal takes place at the border zone of the metastases just around the necrotic center. We conclude that the enhanced local platelet trapping is a major cause for cryothermia-induced systemic thrombocytopenia. (author)

Uranium incorporation biokinetics in poultry bones as function of phytase doses

International Nuclear Information System (INIS)

Arruda-Neto, J.D.T.; Cestari, A.C.; Zamboni, C.B.; Saiki, M.; Nogueira, G.P.; Fonseca, L.E.C.; Manso-Guevara, M.V.; Deppman, A.; Likhachev, V.P.; Mesa, J.

2005-01-01

Neutron activation analysis has been used to study uranium incorporation in poultry bones as function of chow doped with: (a) uranium (20 ppm); (b) U-doped food (20 ppm) plus phytase (120 ppm) and (c) U-doped food (20 ppm) plus phytase (180 ppm). To investigate this situation experiments involving several groups of Cobb broilers was performed. Two animals per group were sacrificed weekly up to their adultness and uranium concentration in the tibia was measured. It was observed that the concentration of uranium (μg U/g bone) is decreasing all along the animal life spanning period of 14-42 days. This behavior suggests that the skeleton mass is growing faster than the corresponding accumulation of uranium. The administration of phytase seems not to alter this scenario. (author)

Bioaccumulation of Trace Metals in Bloody Cockle (Anadara senilis) from Ghana: Biokinetics and Human Bioaccessibility Studies

International Nuclear Information System (INIS)

Kuranchie-Mensah, Harriet

2016-07-01

A series of experimental studies has been carried out to study the kinetic of accumulation and human exposure to trace metals using the bloody cockle (Anadara senilis) as a model organism. This species is of ecological and economic importance in Ghana and other parts of Western Africa where they are commonly found. Trace metals mainly Mn, Co, Zn, Ag and Cd were studied using both laboratory mesocosm and field investigations. The laboratory experiments were carried out through the use of radiotracers: "5"4Mn, "5"7Co, "6"5Zn, "1"1"0"mAg and "1"0"9Cd, to study the kinetics of metal accumulation in the cockle through 2 different exposure pathways. The variability of metal bioaccumulation in the bloody cockle as a function of environmental and physiological conditions was also investigated. Metal subcellular fractionation, tissue distribution and simulating human digestion through the use of in vitro methodology were incorporated to understand the processes governing metal accumulation and human health risk assessment from the consumption of contaminated shellfish. Following a 2-hour single feeding and a 28-day depuration period, metals ingested with food (Isochrysis galbana or Skeletonema costatum) were moderate to highly assimilated in the cockle (11 to 72%), although, the degree of assimilation was dependant on the type of phytoplankton strain, the studied metals and the size of the cockle. Retention of assimilated metals was metal dependant being described as weak for Ag (T_b_1_/_2 of 2 to 6 days), moderate for Mn, Co and Zn (T_b_1_/_2 of 13 to 47 days) and strong for Cd (T_b_1_/_2 ≥ 97 days). Over a 28-day dissolved exposure period, bioconcentration kinetics of metals in two size classes of bloody cockles studied under different exposure conditions (high and low salinity) generally were best described by a saturation model assuming an apparent steady state concentration. The results showed strong variability on the kinetics of metal uptake among different size

Workshop on intakes of radionuclides: occupational and public exposure, Avignon, 15-18 September 1997

International Nuclear Information System (INIS)

Etherington, G.; Phipps, A.W.; Harrison, J.D.; Jones, D.G.; Stradling, G.N.

1998-01-01

This meeting was the fourth in this series of Workshops, previous meetings having been held in Versailles, France in 1988, in Elmau, Germany in 1991, and in Bath, UK in 1993. The Avignon meeting comes at a time of intense activity in internal dosimetry. The International Commission on Radiological Protection (ICRP) has recently completed development and publication of a series of physiologically based age-dependent biokinetic models for a range of important radionuclides. This followed the publication in 1994 of the new Human Respiratory Tract Model (HRTM). These models have now been used to determine the dose coefficients that are given in the EURATOM Directive and in the International Basic Safety Standards. A forthcoming ICRP publication will present predictions of the new models for bioassay quantities of interest, and will give revised guidance on the design and interpretation of internal dosimetry monitoring programmes. Another will give technical guidance on the use of the HRTM in practical situations. Looking further into the future, work on the development of a new age-dependent dosimetric model for the gastro-intestinal tract is now under way. With so many recent and forthcoming developments in modelling, it is not surprising that one of the unifying themes of the meeting was the impending need for internal dosimetry practitioners to be able to use the new models for assessments of doses in the workplace. The meeting's main sessions were organised under five headings: occupational exposure to radionuclides, public exposure to radionuclides, developments in modelling, physical dosimetry and treatment of accidental intakes

Radioactive colloids

International Nuclear Information System (INIS)

Bergqvist, L.

1987-01-01

Different techniques for the characterization of radioactive colloids, used in nuclear medicine, have been evaluated and compared. Several radioactive colloids have been characterized in vitro and in vivo and tested experimentally. Colloid biokinetics following interstitial or intravenous injection were evaluated with a scintillation camera technique. Lymphoscintigraphy with a Tc-99-labelled antimony sulphur colloid was performed in 32 patients with malignant melanoma in order to evaluate the technique. Based on the biokinetic results, absorbed doses in tissues and organs were calculated. The function of the reticuloendothelial system has been evaluated in rats after inoculation with tumour cells. Microfiltration and photon correlation spectroscopy were found to be suitable in determining activity-size and particle size distributions, respectively. Maximal lymph node uptake following subcutaneous injection was found to correspond to a colloid particle size between 10 and 50 nm. Lymphoscintigraphy was found to be useful in the study of lymphatic drainage from the primary tumour site in patients with malignant melanoma on the trunk. Quantitative analysis of ilio-inguinal lymph node uptake in patients with malignant melanoma on the lower extremities was, however, found to be of no value for the detection of metastatic disease in lymph nodes. High absorbed doses may be received in lymph nodes (up to 1 mGy/MBq) and at the injection site (about 10 mGy/MBq). In an experimental study it was found that the relative colloid uptake in bone marrow and spleen depended on the total number of intravenously injected particles. This may considerably affect the absorbed dose in these organs. (author)

Targeted radiotherapy with 177 Lu-DOTA-TATE in athymic mice with induced pancreatic malignant tumours

International Nuclear Information System (INIS)

Rodriguez C, J.; Murphy, C.A. de; Pedraza L, M.; Ferro F, G.; Murphy S, E.

2006-01-01

Malignant pancreas tumours induced in athymic mice are a good model for peptide receptor targeted radiotherapy. The objective of this research was to estimate pancreatic tumour absorbed radiation doses after administration of 177 Lu-DOTA-TATE in mice as a therapeutic radiopharmaceutical that could be used in humans. AR42J murine pancreas cancer cells expressing somatostatin receptors, were implanted in athymic mice (n=18) to obtain the 177 Lu-DOTA-TATE biokinetics and dosimetry. To estimate its therapeutic efficacy 87 MBq were injected in a tail vein of 3 mice and 19 days p.i. there were a partial relapse. There was an epithelial and sarcoma mixed tumour in the kidneys of mouse III. The absorbed dose to tumour, kidney and pancreas was 50.5 ± 7.2 Gy, 17.5 ± 2.5 Gy and 12.6 ± 2.3 Gy respectively. These studies justify further therapeutic and dosimetry estimations to ensure that 177 Lu-DOTA-TATE will act as expected in man considering its kidney radiotoxicity. (Author)

Calculation of total number of disintegrations after intake of radioactive nuclides using the pseudo inverse matrix

International Nuclear Information System (INIS)

Noh, Si Wan; Sol, Jeong; Lee, Jai Ki; Lee, Jong Il; Kim, Jang Lyul

2012-01-01

Calculation of total number of disintegrations after intake of radioactive nuclides is indispensable to calculate a dose coefficient which means committed effective dose per unit activity (Sv/Bq). In order to calculate the total number of disintegrations analytically, Birch all's algorithm has been commonly used. As described below, an inverse matrix should be calculated in the algorithm. As biokinetic models have been complicated, however, the inverse matrix does not exist sometime and the total number of disintegrations cannot be calculated. Thus, a numerical method has been applied to DCAL code used to calculate dose coefficients in ICRP publication and IMBA code. In this study, however, we applied the pseudo inverse matrix to solve the problem that the inverse matrix does not exist for. In order to validate our method, the method was applied to two examples and the results were compared to the tabulated data in ICRP publication. MATLAB 2012a was used to calculate the total number of disintegrations and exp m and p inv MATLAB built in functions were employed