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IGC-1231991

Peview of Literature on Bioassay MethodsFor Estimating Radionuclides in Urine

M.V.R. Prasad

D.S. Surya NarayanaR.K. Jeevanram

A.R. Sundararajan

GOVERNMENT OF INDIA. DEPARTMENT OF ATOMIC ENERGY

INDIRA GANDHI CENTRE FOR ATOMIC RESEARCH KALPAKKAM

JG-C —

1991

GOVERNMENT OF INDIA

DEPARTMENT OF ATOMIC ENERGY

REVIEW OF LITERATURE ON BIOASSAY METHODS FOR ESTIMATING

RADIONUCLIDES IN URINE

M.V.R. PRASAD, D.S. SURYA NARAYANA, R.K. JEEVANRAM AND

A.R. SUNDARARAJAN

INDIRA GANDHI CENTRE FOR ATOMIC RESEARCH

KALPAKKAM - 603 102

TAMIL NADU, INDIA

REVIEW OF LITERATURE ON BIOASSAY METHODS FOR ESTIMATING

RADIONUCLIDES IN URINE*

A B S T R A C T

Bioassay methods of c e r t a i n important r a d i o n u c l i d e s

encountered in the n u c l e a r fuel cycle o p e r a t i o n s , v i z . , thor ium,

uranium, Pu-239, Am-241, S r -90 , Tc-99, Ru-106, Cs-137 a r e

reviewed, with spec i a l emphasis on u r i n a l y s i s . Since the

preconcentrat ion is an important prerequisite for bioassay,

various preconcentration methods are also discussed. Brief

account of various instruments both nuclear and analytical used

in the bioassay programme is included. The sens i t iv i t ies of the

methods cited in the l i t e ra ture vis-a-vis the derived recording

levels indicated in ICRP recommendations are compared. Literature

surveyed up to 1990 is tabulated (96 references).

(Key Words: Urinalysis, Bioassay, Preconcentration Methods,

Thorium, Uranium, Pu-239, Am-241, Sr-90, Tc-99, Ru-106, Cs-137)

This report forms part of doctoral work of Sri M.V.R. Prasad tobe submitted to University of Madras.

CONTENTS

1 . INTRODUCTION .. 1

2. BIOASSAY .. 2

2.1. Radionuclide Biokinetics .. 4

2.1.1. Ingestion .. 4

2.1.2 . Inhalation . . 5

2 .1 .3 . Absorption . . 6

2.2. Objectives of Bioassay Programme . . 6

2 . 2 . 1 . Evaluation of Internal Deposition . . 6

2.2 .2 . Evaluation of Control Procedures . . 7

2 .2 .3 . Improved Metabolic Data . . 7

2.3 . Bioassay Techniques . . 8

2.3.1 In-vivo Measurement . . 8

2.3.2 In-vit ro Measurement . . 9

2 . 3 . 2 . 1 . Urine Analysis . . 9

2 .3 .2 .2 . Sampling of Urine ..12

2 .3 .2 .3 . Feces Analysis ..14

2.3 .2 .4 . Blood Analysis ..15

2 .3 .2 .5 . Breath Analysis ..16

2.4. Frequency of Monitoring ..16

3 . PRECONCENTRATION METHODS . . 1 7

3.1. Solvent Extraction ..18

3.1.1. Extraction using chelates ..18

3.2 Extraction Chromatography ..18

3.3 Sorption Methods ..19

3.3.1. Synthetic Ion Exchangers ,.21

3.4. Co-precipitation of Trace Elements ..21

3.4.1. Collectors (carriers) ..22

3.4.2. Inorganic Co-precipitants ..23

3.4.3. Organic Co-precipitants ..24

3.5 Electrochemical Methods ..24

3.5.1. Electrodeposition ..25

4. INSTRUMENTATION ..26

5. ICRP RECOMMENDATIONS FOR INTERNAL DEPOSITION OF

RADIONUCLIDES ..27

5.1. Annual Limit on Intake ..28

5.2. Derived Investigation and Derived recording

levels ..29

6. CONCLUSIONS ..29

7. ACKNOWLEDGEMENTS -.30

8. REFERENCES -.31

1. INTRODUCTION

Indira Gandhi Centre for Atomic Research is a unit of the

Department of Atomic Energy engaged in carrying out Research and

Development activities with special emphasis on the science and

technology related to fast breeder reactors. Some of the

installed facilities which handle radioactive materials include:

Fast Breeder Test Reactor, Radiochemistry Programme, Reprocessing

Development, Centralised Waste Management Facility, and Safety

Research & Health Physics Programme. All safety precautions are

taken in the design and operation of these facilities which

handle the radionuclides associated with the fuel and the fission

products. In spite of good laboratory design, working facilities,

discipline, special training of the staff and planned working

procedures, contamination do occur and spread to many unsuspected

places either due to accidents or otherwise. This results in the

possibility of uptake of the contaminants by radiation workers

through inhalation or ingestion Safety Research & Health Physics

Programme (SRSHPP) of the Centre is entrusted with the

responsibility of conducting effective surveillance on all

radiation workers to ensure safe working conditions. As part of

this surveillance programme, bioassay group of SR&HPP carries out

urine analysis regularly on all radiation workers of the Centre

for radionuclies such as natural thorium, natural uranium, Pu-

239, Am-241, Sr-90, Ru-106, Cs-137 etc. and feces analysis in

certain exposure cases. The methods presently used for estimating

radionuclid as such as plutonium, thorium and uranium, are time

consuming and lack s e n s i t i v i t y . The bioassay group has undertaken

a programme to develop newer methods and/or improve the exis t ing

methods in order to reduce the time and also to improve the

s e n s i t i v i t y of de tec t ion . Recommendations contained in ICRP-54

demand substant ia l increase in the s e n s i t i v i t y of de tec t ion . This

report therefore , reviews the exis t ing methods avai lab le in

l i t e r a t u r e and discusses in de ta i l the importance of bioassay

with special reference to u r ina ly s i s in the in te rna l dosimetry

programme (See Table 1 ) . Since preconcentrat ion methods and

select ion of su i tab le instrumentation are very important steps to

determine the radionuclides in Bioassay methods, sa l ient aspects

of preconcentrat ion and instrumentation ere also discussed in

th i s report .

2. BIOASSAY

Chemical elements present in various biological matrices can

be bas ica l ly grouped in to three ca tegor ies : major elements

consist ing of carbon, hydrcgen, n i t rogen, and oxygen; minor

elements comprising calcijm, chlor ine , magnesium, pnosphorous,

potassium, and sodium; a.id t race elements encompassing the

remainder ' . Bas ica l ly , t'ie major elements act as s t ruc tura l

components while the minor elements maintain the e l ec t ro ly t e

balance to keep the e n t i r e system v i a b l e . The rnaj cr and minor

groups of elements make up most of the body, while a l l the t race

elements combined account for less then 1.% of the t o t a l . Elements

whose concentration l e v e l s fa l l below a few pa r t s per mill ion

are normally regarded as t r a c e s .

Trace elements may be classified into two groups: the

essential and the nonessential. Among the numerous trace

elements, arsenic, chromium, cobalt, copper, fluorine, iodine,

iron, manganese, molybdenum, nickel, selenium, silicon, tin,

vanadium, and zinc are currently considered to be essential for

humans whereas cadmium, mercury, lead and thallium, are non-

essential and known to impair health. Specific elements say,

beryllium, silicon etc., are regarded as industrial hazards.

Elements such as uranium, thorium, transuranics and fission

products released from nuclear reactors are also non-essential

and form a group called radioactive contaminants. On account of

the radioactivities associated with these elements, they pose a

different kind of problem viz., radiation hazards.

The main objective of bioassay is to assure adequate

assessment of occupational workers against the toxic metal ions

that might enter the body. Applications of bioassay are not

limited to radionuclides . They are commonly found in occupational

health programmes dealing with metals (e.g. lead, mercury), and

other industrial chemicals (e.g. fluoride). The normally used

bioassay methods for detecting an internal deposition involve

indirect measurements of either the intake or organ/tissue

burden. However, the bioassay of radioactive materials involves

the measurement of their biological hazards due to their

chemically toxic nature and also the radiation dose they impart

to the orgar.s where they are deposited. Therefore the bioassay of

radioactive materials merits special attention and requires the

understanding of the movement and distribution of metal ions in

the biological systems and also the nature of the decay process

of each nuclide .

2.1. Radi onuclide Biokinet ics

Radionuclides can gain access to the interior of the body

by ingestion, by inhalation, through wounds or by absorption

4through skin as indicated by large arrows in Fig. 1. The

subsequent internal distribution of the radioactive material,

i.e. its metabolism, is determined by the physical and chemical

form of the radioactive material and its associated iji vivo

solubility. The fate of the radionuclides in the body is

governed by the following factors: 1. Permeability, 2. Ligand

Exchange, 3. Transport, A. Assimilation, 5. Storage, 6. Excretion

2 . 1 . 1 . Ingest ion

When a rad ionucl ide i s inges ted , i t passes through the

g a s t r o i n t e s t i n a l t r a c t mixed with the contents of the t r a c t .

During t h i s t r a n s i t , a f rac t ion of the rad ionucl ide may be

absorbed, and the remainder i s excreted in the f eces . The

f rac t ion absorbed can be very high, as .>.n the case of soluble

rad ionuc l ides such as t r i t i u m , iodine or cesium, or very low, as

in the case of r e l a t i v e l y inso lub le f orris of rad ionucl ides such

as plutonium or uranium . The absorbed f rac t ion i s c i r cu l a t ed via

the bloodstream and depending on the element, i t wi l l be

deposi ted in specif.'.c organs where metabolic fac to rs control i t s

depos i t ion and i t s ' u r the r excret ion via the ur ine and feces .

2 . 1 . 2 . Inha la t ion

Various f r a c t i o n s of inhaled m a t e r i a l , depending on p a r t i c l e

INGESTION INHALATIONWOUNDS,

SKIN ABSORPTION

G.I.

TRACT

EXHALATION

LMECHANICAL

CLEARANCE

PROCESSES

VRESPIRATORY

TRACT

PULMONARY

LYMPH

NODES

DISSOLUTIONAND ABSORPTION

PROCESSES

VSITE OFENTRY

Fig.l Schema'Jc representation of routes of entry, metabolic pathways and

possible bioansay samples for internally deposited radionuclides (NCRP 87).

s i z e , a re deposi ted in d i f f e ren t regions of the respiratory-

t r a c t , (Nasopharyngeal, Tracheobronchial and Pulmonary regions)

and the f r ac t ion not deposi ted i s exhaled. The regional

depos i t ion of the inhaled mate r ia l i s inf luenced by the

c h a r a c t e r i s t i c s of the inhaled mate r ia l (ch ie f ly s i ze ) and by the

anatomic and phys io log ic s t a t u s of the s u b j e c t . Once depos i t ed ,

the e l imina t ion and systemic absorpt ion of the mate r ia l a r e

governed by the s i t e s of depos i t ion and by the phys ica l and

chemical p r o p e r t i e s of the inhaled p a r t i c l e s . For i n s t a n c e ,

p a r t i c l e s depos i ted i n i t i a l l y on the c i l i a t e d ep i the l ium of the

r e s p i r a t o r y t r a c t a re c leared rap id ly by mucoci l iary a c t i v i t y

followed by swallowing and passage through the g a s t r o i n t e s t i n a l

t r a c t . Retent ion of mate r ia l deposi ted i n i t i a l l y beyond the

leve l of the c i l i a t e d ep i the l ium ( i . e . below the terminal

b ronch io les ) i s s t rongly influenced by the s o l u b i l i t y of the

mate r i a l in the body f l u i d s . If the inhaled mate r ia l i s so luble

in body f l u i d s , s i g n i f i c a n t absorp t ion to the bloodstream can

occur through the t i s s u e of the upper r e s p i r a t o r y t r a c t or

g a s t r o i n t e s t i n a l t r a c t during t h i s c learance p r o c e s s . Soluble

13 7 90

m a t e r i a l s ( CsCl or SrCl ) a r e qu ick ly absorbed i n t o the

blood stream. R e l a t i v e l y i n so lub l e forms a re r e t a ined in the

pulmonary region for longer times and a re subject to removal by

both mechanical and d i s s o l u t i o n - a b s o r p t i o n p r o c e s s e s . Fac to r s

that can inf luence the in -v ivo s o l u b i l i t y of an i n f e r n a l l y

deposi ted r ad ionuc l ide inc lude i t s elemental chemistry, chemical

form, surface a r e a , and spec i f i c a c t i v i t y . Radionucl ides a r e

c l a s s i f i e d i n to th ree ca t ego r i e s based on t h e i r b io log i ca l

c learance half t imes in the pulmonary region; 1) 'D1 C l a s s :

clearance half time ranges up to 10 days, 2) 'W Class: Clearance

half time ranges from 10 to 100 days, 3) 'Y' Class: Clearance

half time is greater than 100 days.

2.1.3. Absorpt i on

In the case of a puncture v/ound, solubility influences the

rate at which the deposited material will leave the wound site

via the lymph and enter the circulation for distribution to

vari ous organs .

2.2. Object ives of Bi oa ssay Programme

2.2.1. Evaluat i on of Int ernal Deposi t i on

The primary use of bioassay methods is to determine whether

an individual has been exposed to a radioactive material in a

manner that resulted in an internal deposition and, if so, to

quantify the magnitude of that deposition and its dosimetric

consequences. It plays an important role in the medical

management of potentially over-exposed individuals. Routine

scheduled measurements, performed periodically after an

individual is on the job, provide important input for evaluations

of the extent to which the individual is adequately protected, is

observing safe working practices, and is avoiding the

accumulation of internally deposited radionuclides. Bioassay

results may be obtained when an individual takes up new job

assignment and when an individual terminates a particular job

assignment to document the estimated body or organ burden at that

t ime .

2.2.2. Evaluat ion of Cent rol Procedures

Bioassay provides a useful tool for evaluating the general

conditions of exposure throughout an operating facility. It gives

important base line data and provides useful background

information on exposures that might have occurred in past

occupational assignments. It can indicate trends towards greater

or lesser accumulations of radioactivity within the working

population. Bioassay results can provide information on

possible exposures associated with unusual procedures for which

experience is not available, and on exposures that have been

occurring but were not suspected. These results can also indicate

the extent to which engineered confinement-measures and the air

sampling programme have been effective in the control of the

exposures .

2.2.3. Improved Metaboli c Data

Many guidelines and standards are based, in large part, on

results obtained from laboratory animals exposed to radionuclides

by different routes of administration. The models used in these

documents are based on appropriate extrapolations to human

exposures. Thus, the bioassay data from human exposures are

invaluable in the development of standards and the validation of

extrapolations of •animal data.

2.3. Bioassay Techniques

Bioassay is the determination of the kind, quantity,

location, and/or retention of radionuclides in the body. Bioassay

methods are used to estimate the body-burden of radionuclides and

their distribution among different organs due to internal

radiation exposure. Because the direct anal/sis of tissue samples

is seldom possible in living persons, other methods must be used.

The two main types of bioassay measurements are:

*) In~vivo measurements (Whole Body Counting)

2) In-vit ro measurements (Analysis of Urine, feces, blood,

breath et c . )

2 .3 .1 . In-vivo Measurement s

In-vivo measurements are those in which the emission of

photons from internally deposited radionuclides is detected

external to the body. It is commonly used for routine

surveillance of workers to detect possible unknown exposures and

to measure the quantities in the body and, possibly, organs when

such an exposure is detected.

Many different types of systems (generally described as

whole-body counters) have been devised to accomplish these in-

vivo measurements. In a laboratory setting, systems in use range

from single, unshielded detectors to heavily shielded (with lead

or steel) multi-detectors . Factors that can influence the

complexity of the system include the accuracy and precision

required, the distribution and behaviour of the material in the

body, and the nature of the radiations emitted. The detector may

be a solid, inorganic scint i l la tor (e.g. Nal(Tl)) or an organic

scint i l la tor in either a liquid or solid form.

Multiple, fixed-position Nal detectors provide more

sensitivity and geometry independence than a single crystal while

s t i l l maintainina the resolution inherent in Nal detectors.

Obviously, the initial cost and the maintenance needed for the

electronics increases considerably with the number of detectors

used. A hyperpure germanium detector provides better energy

resolution than the other systems. Multi-detect or arrays of

hyperpure germanium detectors have been successfully used to

238 23Q 241quantify lung burdens of actinides such as Pu, Pu, Am,

U and ^°U. Thyroidal uptake of 1 0 1I or I is readily

monitored by an external Nal(Tl) probe.

2.3.2. In-vit ro Measurement s

2.3.2.1. Urine Analysis

The urine specimen has been referred to as a liquid tissue

biopsy of the urinary tract, painlessly obtained. Nutritional

state, the state of metabolic processes, and the ability of the

kidney to selectively handle the material presented to it are the

three principal factors affecting the composition of the urine.

About 1200 cm /min of blood passes through the kidney,

exposing the plasma to the semipermeable membrane of each

functioning glomerulus. The ultrafiltrate that collects in

Bowman's capsule contains all the substances of plasma capable of

passing through the membrane. Modification of this filtrate

occurs in the tubules and collecting duct of the nephron to

produce the urine. The average daily excretion of urine in normal

adult is 1400 cm (normal range is 600 - 2000 cm ).

A large proportion of urine solute is made up of urea and

sodium chloride. Other than nitrogenous material ( e.g., ammonia,

creatinine, etc.) and salts (e.g., sulphates and phosphates),

urine contains small amounts of sugar and intermediary

metabolites such as oxalic acid, citric acid and pyruvate. Free

fatty acids and trace amounts of cholesterol are also found, as

are trace amounts of metals. Hormones such as ketosteroids,

estrogens, aldosterone, and pituitary gonadotrophins and biogenic

amines (catecholamines and serotonin metabolites) are normally

found in the urine and reflect metabolic and endocrine status.

Vitamins such as ascorbic acid are excreted in amounts that

depend on the sufficiency of dietary intake. Trace amounts of

porphyrins and delta-aminolevulinic acid are present. Normal

urine contains traces of red blood cells and leukocytes, renal

tubular epithelial cells, transitional epithelial cells, and

squamous epithelial cells, which represent normal sloughing off

of aged cells^

Urine analysis for radioactive material provides a useful

assessment of the existing systemic burden. Urine analysis can be

par t i ci'larly useful when equipment and facilities for external

detection of radionuclides are not available on a routine basis.

3 14Also, because some radionuclides, such as H or C, emit low

energetic beta particles without accompanying gamma photons,

external detection is not possible. Periodic routine analysis of

urine indicates an internal exposure that may not have been noted

through an air sampling programme. Urine analyses can be used to

assess the performance of the radiation protection control

practices. Also, in the case of an individual with a known body-

burden of a radionuclide, sequential analyses of urinary

excretion may provide the basis I r estimating the fraction of

the annucl limits on intake that was deposited in a transferable

10

form. When a radionuclide reaches the circulation in ionic or

complexed form, fractions are deposited in different organs and

filtered by the kidneys depending on the chemistry of the

radionuclide. This fraction is subject to dynamic equilibrium

based on the chemistry of the radionuclide and the cellular

dynamics and biochemistry of the target organs. The radionuclide

subsequently released from these organs by cellular turnover or

other kinetic processes, re-enters the bloodstream where it again

undergoes fractionation (including possible translocation to

another body organ) with continuing excretion in the urine and

feces. Thus one can derive an indirect assessment of the amount

remaining in the body from measurements of the amounts of a

7 8 9radionuclide excreted from the body ' ' .

Since the method is an indirect assessment of body-burden,

one must adopt a model that describes the expected behaviour of

the material in the body and the temporal excretion

relationships. One of the limitations of urine analysis is the

degree to which the behaviour of the material in the subject

being tested matches that incorporated in the model being used.

Discrepancies of this sort can be caused by differences in the

subjects, the forms of the material deposited, and the mode of

intake.

Long-term retention of radionuclides with nearly uniform

' 137distribution throughout the body, e.g. ""H and Cs can be

adequately described by a single exponential function. In such

cases, the urinary excretion should represent a constant fraction

of the total existing body burden regardless of the elapsed time

11

after exposure. For other radionuclides, the urinary excretion

patterns are best represented by multiple exponential functions,

power functions or their combinations, and it is necessary to

know the time elapsed between exposure and sample collection to

relate urinary excretion to body burden. The time after a single

exposure may be known. When the subject has accumulated multiple

depositions, however, the effective time after exposure is

difficult to determine in relation to the model used.

Interpretation of the data is also complicated when the

individual i s , or has been, undergoing chelation therapy for

removal of the deposited material because the levels of

radionuciide excretion in the urine will be elevated over those

observed without chelation.

2.3.2.2. Sampling of Urine

Care must be exercised in the collection of bioassay samples

to prevent contamination. Clean containers must be used for

collection and storage; single-use containers can meet this

requirement most readily. All biological samples are also subject

to deterioration by bacteriological action that may interfere

with subsequent analysis. Prompt analysis following collection is

the preferred method of avoiding these complications. When

samples must be kept longer than a day, they should be

refrigerated, acidified to minimize precipitation, or have a

preservative added ;o prevent bacterial growth. For some

analytical techniques, it may be appropriate to add a carrier to

minimize losses to the container walls or to obtain high recovery

of the T.adi oact iv= material .

12

In many dosimetric evaluations, the quantity of radioactive

material excreted per 24 hours is required and is obtained by

collecting a 24-hour urine sample. For a routine bioassay

programme, collection of 24-hour samples may be diff icult because

collection is required both at home and during working hours when

the possibi l i ty of sample contamination is high. Samples

collected just before ret i r ing at night and al l samples until and

including the f i rs t voiding after rising in the morning on two

successive days will approximate the volume of a 24-hour sample,

and such samples are suitable for many s i tuat ions . Such samples,

called incremental samples, represent the integral excretion over

the collection period, and account must be taken of this if the

excretion rate i s changing rapidly during this period. For some

materials, such as natural uranium, 24-hour samples are not

essential for control purposes. Analysis of a single voiding will

give adequate evidence cf exposure if any. In this case,

consideration must be given to the time of sample collection.

Except when true 24-hour samples are collected, some

correction of the concentration measurement may be required to

account for abnormal conditions of high or low fluid intake or

excessive loss of water by perspirat ion. This correction is

frequently made by relating the specific gravity (sp.gr.) of the

sample to the average sp.gr. of urine which is 1.024 g/cm . The

correctinr to be applied is determined from the relation

Corrected concentration

= (n.easuted concent rat i on )(1 . 024 -1 )/(measured sp.gr. - 1)

13

An alternative correction may be made based on the fact that

creatinine is excreted at an average rate of 1.7 g/d for men and

1.0 g/d for women . The ratio of the expected creatinine content

to the measured creatinine content of the sample provides a

correction to convert the amount of radioactive material in the

sample to the equivalent of a true 24-hour collection. Sample

volume for a 24-hour collection or the volume collected over a

known time interval may be indicative of a need for correction.

If urine samples are to be taken to evaluate exposure or dose

following an accidental exposure, a urine sample should be voided

immediately following the exposure and cleanup, if possible. This

action avoids dilution of the subsequent sample by urine already

present in the bladder at the time of the incident. This

immediately voided sample may also be analysed to provide

baseline data .

2.3.2.3. Feces Analysi s

Feces analysis is another means of obtaining an indirect

assessment of the body-burden of an internally deposited

radionuclide. It can be useful in detecting and quantifying an

inhalation exposure to a relatively insoluble form of

radionuclide, because clearance via feces is the predominant

12 13excretion mode in such a situation ' . Collection and analysis

of feces sanples, ascertaining and quantifying radioactive

material in them and interpreting the results are more difficult

than in the case of urine. The daily rate of fecal mass excreted

is considerably more variable than the daily rate of urinary

14 15voluine ' . While the specific gravity or creatinine content of

14

the urine can be used to adjust or normalize the result of a

urinalysis, no similar index has been identified for feces.

2.3.2.A. Blood Analysis

Another possible means of estimating the burden in an

individual is to measure the radionuclide content of a blood

sample which would generally be comparable to that obtained from

urine analysis. Blood samples show less fluctuation in

radionuclide content than do urine samples, but the sensitivity

of the analysis is limited, due to the amount of blood that can

be withdrawn from an individual, particularly in the event of an

accident with severe injury. Unfortunately, many elements are

rapidly taken up by organs or bound to tissues and are only

slowly released back to blood. Thus, blood bioassay, even a few

hours after exposure could result in misleadingly low

interpretations of blood activity concentrations. Becuase of

these factors, as well as the ease of sampling urine, blood

sampling is rarely used to monitor the possible uptake of

radi onuclidfjs in individuals working with radioactive materials

under normal conditions. However, in a serious exposure the level

of radioactive material in the blood could be high enough to

allow accurate analysis of a small sample of blood.

2.3.2.5. rSreath Analysi s

Breath samples have been analysed to estimate the internal

deposit! on of radiun. and thorium nuclides. Breath samples can

also bo applied to ;;ome other radioactive materials t! at produce

a gas or vapour in the body. R:-idon-222, the decay product of

2 ° 6

Ha, can be collected with air handling systems that incjude

flasks, sampling bag, spi rornet ers, or charcoal traps (the latter

two permitting measurement of exhalation rate as well as

concentration) and measured with ionization chambers or

scintillation devices. Radon-220, eventual decay product of

2 2 8Th or Th, can be sampled by electrostatically collecting

its ionized daughters and counting with solid state detectors.

2.4. Frequency of Monit oring

If the concentration of radionuclides is normally low (the

time weighted average does not exceed 10% of Derived Air

Concentration) and if transient elevations in this level are

infrequent and not great (not more than three times of the

chronic level) annual bioassays may be adequate. If the average

concentration of radioactive material in air normally exceeds

10% of the Derived Air Concentration and/or transient elevations

tend to be more than three times of the chronic level, it is

unlikely that annual bioassays will adequately monitor the

accumulated radioactive material in the body. Under such

conditions, bioassay measurements should be conducted often

enough to assure that significant depositions do not go

undet ect ed .

For a radionuclide such as inorganic tritium, however, which

has a short effective half life and therefore does not accumulate

in the body, the objective of monitoring does not apply. Bioassay

for such substances, if it is considered necessary for the

particular circumstances, is usually done more frequently than

annually to confirm air sampling results.

16

3. PRECONCENTRATION METHODS

In practice, the chemical analysis demands various

preconcentration techniques depending on the matrix. If the

matrix is simple, i.e., it contains one or two trace elements

then the preconcentration can be effected by removal of the bulk

of the matrix and thereby separate the trace elements. However,

if the matrix contains several elements then it is ideal to

separate trace elements from the matrix. In general removal of

matrix demands large amounts of reagents and time and incurs

losses of the trace elements being concentrated . Hence removal

of matrix is not a preferred method for bioassay of urine

samples.

Selecting a preconcentration method is mainly governed by

(I) the nature of the trace elements to be determined, (II) the

combination of the selected method and subsequent method of

determination of trace elements in a concentrate, (III) the

simplicity, the availability and the duration of the method, (IV)

the availability of the equipment and (V) mutual effects of the

matrix and trace elements in the process of sample treatment.

3.1. Solvent Ext racti on

Solvent extraction is a method of isolation, separation and

concentrations of substances; it is based on the distribution of

dissolved substances between two immiscible liquid phases. Most

commonly water forms one phase and the organic solvent the other.

This method can be applied both for the removal of matrix and for

the selective, group, or subsequent separation of trace elements

17

effectively. The important advantage of extraction methods is

that they are universal with respect to the type of elements to

be isolated and to their concentration. Simplicity and rapidity

are other advantages of these methods. Usually solvent

extraction can be combined with different methods of subsequent

det erminat i on.

3.1.1. Ext ract i on u sing chelat es

For extracting trace elements chelates are often used. These

are compounds of metals with organic polydentate reagents. The

general formula of most common chelates is MA , where A stands

n

for the anion of the reagent which is a weak acid and n

represents the metal ion charge. Chelates can be coordinatively

saturated and unsaturated. In the l a t t e r , the central atom of

metal is capable of adding neutral ligands, such as water, into

the inner coordination sphere. Thus, the nature of the solvent

has a marked effect on the extraction of chelates. Coordinatively

saturated complexes are extracted with different solvents.

Group extraction of trace elements pursues the objective of

isolat ing a maximum number of elements in a single step using a

minimum number and amount of chelate-forming reagents which can

be easily purif ied. The composition of the aqueous phase

significantly affects the extraction efficiency of chelates.

3.2. Ext ract i on Chromat ography

Extraction chrorr.at ography is an effective method of

concentration and separation. It can be regarded as a peculiar

variant of continuous extraction- the compound to be extracted is

18

distributed between two liquid phases, one of which is fixed on.

a solid inert carrier placed in a column, while the other travels

along the column. The chemical nature of the process happens to

be extraction, while the technique of carrying out the process

is chromatography. In a number of cases, column extraction

chr^matography has advantages over the usual solvent extraction.

Elements with almost similar properties can be separated, e.g.

lanthanides, act inides, zirconium-hafnium, niobium-tantalum, e tc .

Other advantages include the high degree of absolute

concentration and the possibi l i ty of carrying out experiments in

s t e r i l e and isolated conditions and , hence of lowering the value

and the fluctuations of the blank experiment correction compared

to conventional extraction. Extraction chromatography can be

easily controlled to achieve group or selective concentration.

Good results can be obtained by correct selection of the

extraction system and the composition of the aqueous phase,

part icular ly by adding masking-substances, oxidisers, reducers,

and also by controlling of the conditions of separations. The

la t t e r depends on the parameters of the chromatographic column,

e.g. , height of the theoretical plate (HTP) and the number of

such p la tes . HTP depends on the column contents, the nature and

granulation of the carr ier , the elution ra te , temperature, the

type of extractant and i t s amount, i t s degree of dilution with

17neutral solvents and the composition of the aqueous phase

3 . 3 . SORPTION METHOD 5

Sorpcion techniques prove to be most e f f ec t ive in those

cases when the subsequent method of determinat ion may suffer from

19

mutual interfering effects of trace components. The mechanisms

involved in sorption phenomena are many, viz., (I) adsorption

(sorption of substances on the surface of a solid or liquid

body), (II) absorption (sorption of gases, vapours or substances

dissolved in the volume of a solid or liquid phase), (III)

chemisorption (sorption of substances by solid or liquid sorbents

with the formation of chemical compounds) and (IV) capillary

condensation (formation of a liquid phase in the pores and

capillaries of solid sorbent during sorption of vapours of the

substance). In practice it is difficult to encounter separately

any of the above mentioned types of sorption: they are generally

used in combination with each other. For e.g., adsorption usually

precedes chemisorption. Adsorption and chemisorption methods are

widely used for concentration of trace elements. Among the latter

extensive use is made of ion-exchange and sorption which is

accompanied by complex-formation, say, on chelate forming-

sorb ent s .

Sorption generally ensures good separation and high values

of concentration coefficients. For concentration of trace

elements use is made of different sorbents which, besides having

good sorption power and selectivity, should have the ability to

be easily regenerated, and be chemically and mechanically stable.

The following sorbents are in general use: normal and modified

cellulose, ion-exchange and chelate synthetic sorbents and

different inorganic sorbents. For quantitative estimation of

sorption, use is made of the degree of separation and the

distribution coefficient.

20

3.3.1. 5yntheti c Ion Exchangers

Synthetic ion exchangers are usually made of copolymers of

styrol and divinylbenzene having divinylbenzene cross-links. The

degree of cross-links determines many important properties of the

the sorbent , in particular, swelling ability and sorption rate.

Use is mostly made of strongly cross-linked sorbents (up to 10 or

more percent divinylbenzene) which comprise fine grains (100-400

mesh). Ion exchangers with acidic groups (S0«H ) can exchange

cations, and are called cation exchangers; sorbents with basic

groups [N(CH3)30H ] can exchange anions, and are known as anion

exchangers. The essence of an ion-exchange process is to replace

the sorbent counterions (for instance, H in the case of SO H )

with the ions of the elements to be concentrated, which are

present in the analysed solution. In an ion-exchange method, use

is often made of complexes of elements present in the analysed

solution or especially obtained prior to preconcentration.

Complex formation enables the difference in sorption behaviour of

separated elements to be increased, sometimes very significantly;

in particular, one of the elements to be separated is transferred

into an anion complex and the other is kept as cation. For

example, anionic complex of plutonium hexanitrate is adsorbed on

the anion exchange resin while other actinides are eluted, to

46achieve the separat ion of Pu in urine

3.4. Co-precipi t a t i on £j t race element s

Co-prec ip i ta t ion i s the t rans fe r of a substance in to a

p r e c i p i t a t e of some compound if the substance does not form i t s

own solid phase under given condi t ions . Co-prec ip i ta t ion i s the

21

best suitable and much more extensively used method of

preconcentration for the separation of trace elements. Greater

selectivity in co-precipitation can be attained by masking,

changing the oxidation state of elements, and by applying other

techniques. Co-precipitation is mainly due to adsorption of the

trace component on the surface of the collector and/or the

formation of isomorphic mixed crystals. The formation of mixed

chemical compounds, occlusion and mechanical inclusion of small

amounts of other phases also favours co-precipitation. Sometimes

all these factors act simultaneously to some extent. Adsorption

increases with the growing surface area of the crystal and with

the decrease in the solubility of the compounds of the trace

element which it (the element) forms with oppositely charged ions

of the crystal .

The precipitate formation process is quite complicated and

often it does not proceed instantaneously. Its progress depends

on various factors, such as composition of the aqueous phase, pH,

temperature, nature of the counter-ions forming the precipitate,

sequence in v/hich solutions are mixed, and the properties of the

collectors. Co-precipitation on inorganic and organic collectors

ensures high efficiency of absolute concentration.

3.4.1. Collect ors (Carriers )

The collectors (carriers) of trace elements must meet

specific requirements. They must entrap the necessary element

without picking up the matrix and interfering trace elements.

The main requirement is that the collector should easily separate

22

from the matrix solution by just f i l ter ing, centrifugation and

washing the precipitate. It is desirable that the collector

should be available readily and measured easily. For e.g.,

Fe(III) and Al(III) are the most widely used collectors for

concentrating radioactive trace elements in urine.

In certain cases there is no need to specially introduce an

element carrier, for it is already present in the solution to be

analysed in micro- or macroamounts. In such cases, the matrix is

part ial ly precipitated by regulating the amount of the added

precipitant. This technique i s , however, applicable only when

the solubility product of the precipitated compound of the matrix

element is more than the solubility product of the corresponding

compounds of trace elements. The most common technique is to

introduce the element-carrier and a suitable co-precipitant into

the analysed solution. The co-precipitants can be classified as

inorganic or organic co-precipitants.

3.4.2. Inorgani c co-precipitants

For co-precipitation of trace elements with inorganic

collectors, use is often made of amorphous precipitates with

large active surfaces (hydroxides, sulphides, phosphates and

others). For example, most of the actinides in urine are being

concentrated by co-precipitation with calcium as phosphate

(Table 1). Plutonium is co-precipitated in the form of ferric

hydroxide and Tc-99 in the form of copper sulphide ' '

The precipitates formed in the sorption processes have a

large surface and porous structure, and therefore the whole

23

volume of the finely dispersed prec ip i ta te is easily accessible

to the ions present in the solution. These processes can be both

physical and chemical, Examples (I) ion exchange observed in the

co-precipi tat ion of sulphides and hydroxides, (II) exchange of

cesium ions with ammonium ions on Ammonium Molybdo Phosphate in

24 25the estimation of cesium in urine '

3 .4 .3 . Organic precipi tant s

The effectiveness of organic co-precipi tants i s so great

that a trace component can be isolated even when i t i s present in

solutions in the ra t io of 1:10. Organic co-precipi tants often

separate out in the p rec ip i t a t e on mixing the solution to be

analysed with solutions of reagents. Ion associates containing

methyl viole t cation and complex thiocyanate anion of uranium co-

prec ip i t a t e to form sparingly soluble p rec ip i t a te in the

77determination of natural uranium in urine . In th i s case the

element enters into the composition of the complex anion. Other

examples of organic co-precipi tants include potassium

rhodizonate for strontium estimation , tetraphenyl arsonium

chloride for Tc-99 determination and Sulkowich reagent for Pu

1 ft *} C

estimation in urine '

^ • 5 • E1ec11ochemi ca1 method s

Electrochemical methods of preconcentration (electrodeposi-

tion, cementation, electrodialysis and others) are used for

analysis of various natural and industrial materials. These

methods ensure high efficiency of preconcentrat ion. Techniques

involving electrochemical concentration (ECC) make it possible to

vary the elemental composition of the concentrate by changing the

24

conditions under which electrochemical processes proceed. They

do not require large amounts of chemical reagents (here

electr ic i ty is the main reagent) and are accessible practically

for any laboratory.

3.5.1. Electrodeposition

Electrodeposition is the most commonly used method of

electrochemical concentration. The behaviour of an element during

electrolysis is determined by i t s electrochemical potential , the

general composition of the electrolyte, current density, material

and design of electrode, temperature, mixing rate and the

constructional features of the electrochemical ce l l . In the

electrolysis of multicomponent solutions, the voltage applied at

the cell is more negative (for cathode processes) or more

positive (for anode processes) than the values of the

equilibrium potential of the corresponding oxidation-reduction

systems calculated by the Nernst equation. The cathode processes

are of great significance for preconcentration, which can be used

for both separation of macrocomponents and concentration of trace

elements. Since trace elements are electrodeposited from very

dilute solutions, the rate at which the components are

transported to the surface of the electrode and the electrode

potential become important factors. Electrodeposition i s used for

concentration of trace elements prior to their determination by

other instrumental methods. In the bioassay, this method is used

for deposition of Pu on the stainless steel planchet and the same

is counted by alpha spectrometry.

i*. INSTRUMENTATION

Instruments commonly used for bioassay of radionuclides

(Table 2) are alpha counters {like alpha scintillation counters,

alpha spectrometer, liquid scintillation counter), low beta

counter, gamma ray spectrometers using Nal(Tl) or hyperpure

Germanium detectors etc. Nuclear track counting technique is also

used for low level measurement of alpha emitters. In addition to

nuclear instruments, spectrophotometer and fluorimeter are also

used for some of the radioelements having very low specific

activity such as thorium and uranium.

Sensitive detection methods are essential for effective

radiation exposure control programme. Annual limit on intake for

alpha emitting radionuclides is very low. Fission Track counting

met nods can be used for plutonium estimation in urine but it

takes ,—'30 days time to detect the reference levels specified by

ICRP . Alternatively, alpha spectrometer, gives good resolution

(20 keV at 5.5 NieV) and very low background under the vacuum

condition of 100 mPa - 100 uPa required for the instrument

operation. This instrument is very useful for simultaneous

determination of nuclides emitting alphas of various energies.

Pu, Th and U are routinely being monitored in urine using this

instrument. In order to meet the reference levels specified by

ICRF1, it is necessary to improve the sensitivity of detection for

the above nuclides in urine.

As chemical separation yields are already extremely high,

the detection limit can only be improved significantly by

optimising the operation of the counting device (background.

26

efficiency) and by extending counting time. The background

results from both natural background radiation and nioses in the

detection systems. This can be brought down by using appropriate

shielding and special electronic circuits. Counting time cannot

be markedly increased due to practical limitations.

Improving the detection limit without chemical processing of

the sample is the most advantageous method. In a modern bioassay

programme, computer assisted Nal(Tl) and hyperpure Germanium

detectors are routinely being used for detecting the gamma

emitting radionuclides in urine. Background of these detectors

depends on the energy of the radionuclide to be counted and

increases as the energy decreases. Efficiency falls exponentially

with the energy of the nuclide. It also depends on the distance

from the source; efficiency increases as distance from the source

decreases. In general HPGe detector efficiency is ten times less

than the efficiency of Nal(Tl) detectors but gives good

resolution and much lower background. Detection limits for the

nuclides depends on the background reading in the integrated

channels. J".n general these background readings are very low for

HPGe detectors. It is therefore, preferable to use HPGe

detectors for routino monitoring of gamma nuclides in urine.

5 . ICRP RECOMMENDAT .IONS FOR INTERNAL DEPOSITION OF RAD IONUCL IDES

The International Commission on Radiological Protection

(ICRP) poriodical1y brings out reports containing recommendations

to ensi re the exposures of radiation workers and the public are

kept wisll within the safe limits. ICRP-54 contains details of

27

individual monitoring for intakes of radionuclides by workers

including design and interpretation.

It is mentioned that a great improvement in the detection

limit is needed because the derived recording levels for routine

monitoring mentioned in ICRP-54 are lower than the detection

limits reported in literature (see Table 3). The aim of the

Bioassay programme is to assess the amount of radionuclide

present in the body, estimate the resulting exposure and compare

it with limits prescribed by ICRP. These limits are given in

terms of Annual Limit on Intake, Derived investigation and

Derived recording levels.

5.1. Annual Limi t on Intake (ALI)

ALI is the greatest value of intake 'I' which satisfies both

the following inequalities

I, £. WT (H50 T per unit intake) <: 0.05 Sv and

I, (H per unit intake) •£ 0.5 Sv

which represent respectively the limits for st ochasv. i r. and non-

st ochast i c ef feet s .

Here, I = Annual intake of the fjiven radi onucl iie either by

inhalation or ingestion ( it is expressed in Bq)

V.' - Weighing factor .md

K T per unit intake- = commi 11 r. H dose equivalent in Tissue

(T) from the intake of ui.it activity of the giver, radionuclide by

the specified route in :50 /ears following the intake (expressed

in SvDq )

28

5.2. Derived Invest igat i en and Derived Recording Levels

The quantities normally measured in individual monitoring

programmes for intakes of radionuclides are body or organ

content or activity excreted per unit time. It is convenient to

compare the measured results directly with Derived reference

levels, viz.. Derived investigation level (DIL) and Derived

recording level (DRL). Calculations of Derived reference levels

require assumptions about the time and pattern of intake and the

use of models of intake, deposition, metabolism and retention.

Derived investigation and recording levels are calculated

separately and are given in ICi?P-54.

6. CONCLUSIONS

Various methods c i ted in l i t e r a t u r e for car ry ing out the

a n a l y s i s of r a d i c n u c l i d e s in u r ine have been reviewed. Minimum

de tec t i on l i m i t s repor ted in the l i t e r a t u r e a re compared with

the Derived recording l e v e l s spec i f ied by ICRP for rou t ine

monitoring purpose . '-is per the Table 3, Cs-137 and Sr-90 can be

de tec ted much below the reference l e v e l s ind ica ted by ICRP-54 for

rou t ine monitoring purpose . The method for assay of plutonium in

u r i n e which g ives d e t e c t i o n l i m i t s lower than the recording level

speci f ied by ICRP i s by F i ss ion Track a n a l y s i s which takes < 30

days . This time dura t ion i s r a the r laxgn for rou t ine monitoring

schemes. In the case of uranium, to achieve s imi la r ob jec t ive one

has to use Thermal I c n i s a t i o n MJSS Spectrometry which i s an

expensive equipment. Ii the case of Ru-106 (Class Y), the

de t ec t i on l imi t (20 Bq/dro' ) for ur ine assay quoted in ICRP 54 i s

not adequate for rou t ine monitor ing. Radionucl ides such as

29

n a t u r a l t h o r i u m ( I ' h - 2 3 2 ) a n d U r a n i u m - 2 3 5 a r e n o t d e t e c t e d a t t h e

r e f e r e n c e l e v e l s s p e c i f i e d b y I C R P . i t i s n o t e d t h a t t h e r e

e x i s t s a g o o d s c o p e f o r d e v e l o p m e n t o f a n a l y t i c a l m e t h o d s f o r t h e

d e t e r m i n a t i o n o f R u - 1 0 6 , n a t u r a l t h o r i u m , n a t u r a l u r a n i u m a n d P u -

2 3 9 i n u r i n e w h i c h w o u l d o f f e r h i g h s e n s i t i v i t y w i t h m i n i m u m

a n a l y s i s t i m e a n d a t l o w c o s t .

7 . A C K N O W L E D G E M E N T S

A u t h o r s w i s h t o e x p r e s s t h e i r s i n c e r e t h a n k s t o S r i L . V .

K r i s h n a n , H e a d , S a f e t y R e s e a r c h & H e a l t h P h y s i c s P r o g r a m m e , f o r

t h e e n c o u r a g e m e n t a n d s u p p o r t g i v e n t h r o u g h o u t t h e p r e p a r a l i ^ n r>f

t h i s r e v i e w . A u t h o r s a r e g r a t e f u l t o D r . P . R o d r i g u e z , H e a d ,

M e t a l l u r g y a n d M a t e r i a l s P r o g r a m m e a n d D r . O . M . S r e e d h c . r a n ,

H e a d , T h e r m o d y n a m i c s S e c t i o n , M e t a l l u r g y D i v i s i o n , f o r v a l u a b l e

d i s c u s s i o n s a n d s u g g e s t i o n s .

30

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3. Friberg, L."The Rationale of Biological Monitoring of Chemicals with specialReference to Metals"Am. Ind. Hyg. Assoc. J. 46, 633 (1985).

4. "Use of Dioassay Procedures for Assessment of Internal Radi onu elideDeposi t i on , "NCRP Wo.87, Hethesda, Maryland (1987).

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6. ''Assessnebt if Radioactive Contamination in Man 1984"IAEA Publication No.STI/PUB/674, IAEA, Vienna (1985).

7. Jackson. 5. and Dolphin, G.W.' T h e e s t i m a t i o n of I n t e r n a l R a d i a t i o n Dose from M e t a b o l i c andU r i n a r v e x c r e t i o n d a t a f o r a number of i m p o r t a n t R a d i o n u c l i d e s , "H e a l t h P h y s . , 1 2 , 481 ( 1 3 6 6 ) .

8 . " R e p o r t of C o m m i t t e e IV on E v a l u a t i o n of R a d i a t i o n D o s e s t o BodyT i s s u e s f rom I n t e r n a l C o n t a m i n a t i o n Due t o O c c u p a t i o n a l E x p o s u r e , "ICRP 1 0 , Pe rgamon P r e s s , New York ( 1 9 6 8 ) .

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i C . " C r i t e r i a f o r a Recommended S t a n a d a r d - O c c u p a t i o n a l E x p o s u r e t oHen z e n e , "i i ! r V ; P u b l i c a t i o n ( N I O S H ) 7 4 , V . S . G o v t . P r i n t i n g O f f i c e ,V . 'a s h i r i g t o n , D . C . ( 1 9 7 4 ) .

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I . . . L a k i n s , J . D . anri M o r g a n , / . .

'"i h c r o l e c £ f e c a l a n a l y s . s ; ;i a b i c a s s a y p r o g r a m m e , "

A s s e s s m e n t ' i f i i a d i o a c t . v i e / i n Mc ,n , " _1 , I A E A P u b l i c a t i o n

'Ac . S T T / P U B / 8 4 , I / v ^ A , V i e n n a , p . 2 3 1 ( 1 9 c 4 ) .

3 1

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15. "Report cf the Task Group on Reference Man,"ICRP Publication No. 23, Pergarnon Press, New York (1975).

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19. Butler, F.E."Determination of Uranium and Americium-Durium in Urine by LiquidIon Exchange,"

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22. Gautier, M. A."Manual of Analytical Methods for Radiobi 0assay,"LA-9763-M, R100-1 (1983).

23. Larsen R.P., Walkup, R.E. an! Oldham, R.D."Method for the Determination of Am-241 ir, Urine,"ANL-78-65 (pt.2), 153 (1978).

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A M P - C h l o r o s t a n n a t e M e t h o d , "j . R a d i o a n a l . Nuc l . Chem. A r t i c l e s , 1 2 5 ( 2 ) , 431 ( 1 9 8 8 ) .

2 6 . G a u t i e r , M. A."Manual of A n a l y t i c a l M e t h o d s t o r R a d i o b i o a s s a y , "LA-9763-M, R 1 2 0 - 1 ( 1 9 8 3 ) .

2 7 . D e r e c k i , J . , G e i s l e r , J . , J a n k o v i c , D. and J a w o r o w s k i , Z ." Q u i c k M e t h o d s f o r R a d i o c h e m i c a l A n a l y s i s , "IAEA T e c h . R e p o r t N o . 9 5 , p . 7 , IAEA, A u s t r i a ( 1 9 6 9 ) .

2 8 . K o p r d a , V . , S c a s n a r . V . and G a l a n , P ." S e p a r a t i o n of C s - 1 3 7 and S r - 9 0 f rom m i n e r a l i z a t e s of B i o l o g i c a lM a t e r i a l s by D i c a r b o l l i d e of C o b a l t , "J . R a d i o a n a l . C h e m . , 8 0 ( 1 - 2 ) , 55 ( 1 9 8 3 ) .

29. Naumann, M. and Ubl, G."Radiochemical Determination of Plutonium in Urine in the presenceof Complexing Agents,"J. Radioanal. Chem., 58(1-2), 341 (1980) (in German)Anal. Abstr. 40, 4D47 (1981).

30 . Veselsky, J .C."Routine Procedure for Determination of Trace Amounts of Plutoniumin urine, "Mikrochim. Acta 1(1-2), 79 (1978).

31. Weiss, H.V. and Shipman, W.H."Radiochemical Determination of Plutonium in Urine,"Anal. Chem., 33, 37 (1961).

32. Kamala Rudran, Kamath, P.R."Determination of Plutonium in Urine,"IAEA Tech. Report No. 95, p.31, IAEA, Austria (1969).

33. Schieferdecker, H."Determination of Plutonium in Urine,"IAEA Tech. Report No.95, p.29, IAEA, Austria (1969).

34. Silker, W.B."Rapid Determination of Plutonium in Urine,"Health Phys . , 11(9), 965 (1965).

35. Cautler, M. A."Manual ol Analytical Methods lor Kadi ob 1 Od L.«y , "LA - 9763 - M, R190-1 (19810 .

36. Clanet, F., Ballada, J., Lucas, J. and Gill, C."Determination of Urinary Plutonium by Radiochemical Analysis onIon exchage filters,"Health Phys., 23(2), 244 (1972).

33

3 7 . B a t s c h , J o a n n a a n d G e i s l e r , J a n" S i m p l i f i e d Method f o r D e t e r m i n a t i o n of U r i n a r y P l u t o n i u m , "Chem. A n a l . ( W a r s a w ) , 2 2 ' 6 ) , 1177 ( 1 9 7 7 ) .

3 8 . K a l a i s e l v a n , 5 . , P r a s a d , M.V.R. and J e e v a n r a m , R . K ." E s t i m a t i o n of P u - 2 3 9 i n U r i n e , I n f l u e n c e of S u l k o w i c h R e a g e n t , "J . R a d i o a n a l . a n d N u c l e a r Chem. A r t i c l e s , 1 2 5 ( 1 ) , 41 ( 1 9 8 8 ) .

3 9 . T e s t a , C ." I n d i r e c t M e t h o d s u s e d a t CNEN f o r t h e e v a l u a t i o n of I n t e r n a lC o n t a m i n a t i o n , "IAEA Symposium on " A s s e s s m e n t of R a d i o a c t i v e C o n t a m i n a t i o n i nM a n , " S M - 1 5 0 / 1 8 , 4 0 5 , S t o c k h o l m , IAEA, V i e n n a ( 1 9 7 2 ) .

4 0 . " M e t h o d s of R a d i o c h e m i c a l A n a l y s i s , "WHO T e c h . R e p o r t N o . 1 7 3 , G e n e v a , p . 1 0 4 ( 1 9 5 9 ) .

41. Holgye, Z."Determination of Plutonium in large volumes of Urine,"J. Radioanal. Chem., 54(1-2), 371 (1979).

42. Testa, C ."New Radiotoxicological Methods used at the Italian Nuclear Centreof Casaccia,"CNEN Report RT/PROT (69), 44 (1969).

43. Irlweck, K. and Streit, S."Determination of Uranium and Plutonium in Excretion Analysis,"Mikrochim Acta, II, 63 (197S).

44. Valentin, M., Weyers, C. and Boulanger, R.''Plutonium Uri nanaly si s , "3.L.G. Report 353 (1965).

45. Bellintani, S.A."Study of a dosimetric Methodology for Plutonium by means ofRadiotonological Analysis in Urine," (in Portugese),INIS-BR-1679, lllp. (1988), INIS Atom Index:2_0: 079300 (1989).

45. Gautier, M. A."Manual of Analytical Methods for Radiobioassay,"LA - 9763 - M, R170-1 (1983).

47 . Talvitie, N.A."Radicchemical Determination of Plutonium in Environmental andBiological Sa'noles by I en Exchange,"Anal. Chem., 43, 1827 (1971).

48. Campbell, E.E. and Moss W.D."Determination of Plutonium in Urine by Anion exchange,"Health Ph—j., 11, 737 (1965).

34

49. Kressin, I .K ."Separation of Plutonium in Urine without Sample ashing forDetermination by Alpha Spectrometry,"Anal. Chem., 53, 1270 (1981).

50. Sanders, S. and Leidt, S.C."A New Procedure for Plutonium Urinalysis,"Health Phys., 6, 189 (1961).

51 . Jacobsen , W. R ." I n i t i a l two year experience with the Savannah-River PlutoniumAnalysis Procedure ,"Report ANL-6637, U.S. Atomic Energy Commission (1961).

52. Eakins, J .D ."The Determination of Plutonium alpha a c t i v i t y in Urine by SurfaceAdsorption and Ion exchange,"UKAEA, Unclass i f ied Report , AERE - R5637 (1968).

52. Moorty, A.R. and Schopfer, C . J ."Measurement of At tocur ie Levels of Pu-239 in Urine using Fiss ionTrack Ana lys i s , "Anon Proceedings of the 32nd Annual Conference on Bioassay,Analyt ica l and Environmental Radiochemistry, Gai thersburg, MD(USA)(1986), INIS Atom Index: J_9: 017571 (1988)

54. Moorty, A.R., Henze, D. , Banerjee, 3 . , Sun L.C. and Meinhold, C.B."Fission Track Urine Bioassay of Pu-239,"3rd I n t e r n a t i o n a l Conference on Low-Level Measuremens of Act in idesand Long Lived Radionuclides in Biologica l and EnvironmentalSamples, p . 8 , Bombay, India (1990).

55. Jothi R. Bhaindarkar and Kamath, P.R."Determination of Radioruthenium in u r i n e , "Miciochemical Journa l , 11, 404 (1966).

56. Naumann, M. and Ubl, G."Radiochemical Determination of Ru-106 in Ur ine , "J . Radioanal . Chem., 21 , 497 (1974).

5 7. Boni, A.L."Determination of Total Radiostrontium in Biological Samplescontaining large quantities of Calcium, Selective precipitationwith Potassium Rhodizonate,"Anal. Chem., 35, 744 (1963).

58. Eakins, J .D. and Goran, P.J."A New Method for the Determination of Radiostrontium in Urine,"Health Phys., 12(11), 1557 (1966).

59. Scasnar , V ."Determination of Strontium-90 in Urine by Extract ion withoutAshing, "Anal. Chem., 56(3) , 605 (1984).

35

60. C a h i l l , D.F. and Lindsey, G . I ."Determination of Strontium-90 in Urine by Anion exchange,"Anal. Chem., 38, 639 (1966).

6 1 . Fairman, W.D. and Sedle t , J ."The Determination of l'c-99 in Ur ine , "U.S. Atomic Energy Commission Report , TID-7696, p.10 (1963).

52. Brener, F. , Delia S i t e , A. and Marchionni, V."Determinazione del Tc-99 n e l l e Urine per .la Valutazione d e l l acontaminazione i n t e r n a , "At t i del XX Congresso Nazionale d e l l a Associazione I t a l i a n a diF i s i c a S a n i t a r i a , p.307 (1977).

63. Sandro C a t t a r i n , Lucio Dore t t i and Ulderico Mazzi"Determination of Technetium-99 in Urine by Liquid S c i n t i l l a t i o nCounting to Evaluate In t e rna l Contamination,"Health Phys . , 49(5) , 795 (1985).

64. Kramer, G. H."Determination of Technetium-99 in Ur ine , "Can. J . Chem., 61 , 1949 (1983).

65. "Estimation of Th-232 in Ur ine , "in Methods of Radiochemical Analysis,Joint WHO/FAO Report, No.173, Palais Des Nations, Geneva (1959).

6 5 . Gaut i er , M. A." Manual of A n a l y t i c a l Methods for R a d i o b i o a s s a y , "LA-9763-M, R210-1 ( 1 9 8 3 ) .

67 . P r a s a d , M.V.R., K a l a i s e l v a n , S . , S u r y a n a r a y a n a , D . S . andJ eevanram, R.K."Rapid E s t i m a t i o n of N a t u r a l Thorium in U r i n e , "R a d i o c h e m i s t r y and R a d i a t i o n Chemis t ry Symposium, Nagpur, I n d i a(1930) .

6 8 . Manchuk, V .A . , P a v l o v s k a y a . N .A . , P e t u s h k o v , A .A . ,S p i r i d o n o v , B . P . and C h e r k a s h i n a , T.N." D e t e r m i n a t i o n of U-238 and Th-232 in Ur ine by Neut ron A c t i v a t i o nMethod, "Radiokhirrdya , 2 1 ( 6 ) , 905 (1979) (In R u s s i a n ) ,Anal. Abstr. 40, 4D46 (1981).

69. Pleskach, S .D ."Det ermina: t i on of Uranium and Thorium in Urine by NeutronAct ivat i or. , "Health Phys., 48, 303 (1985).

70. Bezzano, E. and Ghersini, G."A Rapid Colorimetric Method for the Determination of Thorium inHuman Urine , "Anal. Chim. Acta , 38, 457 (1967).

36

7 1 . Tuo, Kuei-Yuan, Wang, Meng-Tsai and Tung" S e p a r a t i o n and F l u o r i m e t r i c D e t e r m i n a t i o n of Uranium in U r i n e , "F e n . Hsi Hua Hsueh, 7 ( 4 ) , 285 (1979) ( in C h i n e e s e ) ,A n a l . A b s t r . 40 , 4D43 ( 1 9 8 1 ) .

72 . K r e s s i n , I . K ."Spectrophotometr:c Method for the Determination of Uranium inUrine, "Anal. Cham., 56(12), 2269 (1984).

73. Korkisch, J. and Steffan, I."Determination of Uranium in Urine Specimens after separation byAni on exchange , "Mikrochim Acta, No.2, 273 (1973).

74. Centanni , F.A., Ross, A.M. and De Sesa, H.A."Fluorimetric Determination of Uranium,"Anal. Chem., 28, 1651 (1956).

75. Gavra, Z., Lapid, J., Givra,Y. and Hemi, A."Fluorimetric Determination of Uranium in Urine followingExtraction with Aliquat-336 , "NRCN-527, 24 (1988) .

76. Gautier, M. A." M a n u a l of A n a l y t i c a l M e t h o d s f o r R a d i o b i o a s s a y , "L A - 9 7 6 3 - M , R 2 8 0 - 1 ( 1 9 8 3 ) .

7 7 . P a v l o v s k a y a , N . A . a n d M a r t a k o v a , P . I ."Simple and Selective Methods for Determining Microgram Amounts ofUranium-238 in Urine,"Radiokhimiya, 19(3), 394 (1977) (In Russian),Anal. Abstr. 34, 5D33 (1978).

78. Dupyk, I. A. and Dupzyk, R.J."Separation of Uranium from Urine for Measurement by Fluorimetry orIsotope Dilution Mass Spectrometry,"Health Phys., 36, 526 (1979).

79. May, M.F., Walker, R.L., Scott, T .G. , Dyer, F.F. andStokely, J.R."The Determination of Uranium in Urine by Isotope Dilution MassSpectrometry using resin bed loading,"Proc. of the 24th Conference on Analytical Chemistry in EnergyTechnology (Anal. Chem. Symp. Series Vol.19), New York, Elsevier,p.161 (1983).

80. Moore, L.L. and Williams, R.L."An Extremely Rapid Method for Determining Nanogram Quan t i t i e s ofUranium in Urine using the Kinet ic Phosphoresence Analyser ,"3rd In t e rna t i ona l Conference on Low-Level Measurements of Act inidesand Long Lived Radionuclides in Biological and EnvironmentalSamples, p . 3 , Bombay, India (1990).

37

81. Kelly, W. R., Fasset, J.D. and Hotes, S.A."Determining Picogram Quantities of Uranium in Human Urine byThermal Ionisation Mass Spectrometry,"Health Phys., 52, 331 (1987)

82. Duarte, C .L . and Szeles,M.S." Determination of Uranium in Urine by Alpha Spectrometry,"IPEN-PUB-258, p.24 (1989).

83. Hinton, E.R."Development of a Multipurpose Alpha-detection Procedure forEnriched Uranium in Urine,"Anal. Letters, 16(B5), 367 (1983).

84. Clanet, F. and Ballada, J."Radiochemial Analysis on Ion Exchange Filters. Determination ofUranium Isotopes in Urine,"Int. J. Appl . Radiat . Isot., 21, 147 (1970).

85 . Levin, L."Liquid Scintillation Method for Measuring Low Level Radioactivityof aqueous solutions. Determination of Enriched Uranium in Urine,"Anal. Chem., 34, 1402 (1962).

86. Brits, R.J.N. and Holemans, E .A."Determination of Uranium in Urine by Delayed Neutron Counting,"Health Phys., 36(1), 65 (1979).

87. Gautier, M.A."Manual of Analytical Methods for Radiobioassay,"LA-9763-M, R260-1 (1983).

85. Currie, L.A., France, G.M. and Mullar, P.A."Radiochemical Determination of Uranium of Low Activity,"Health Phys., 10, 751 (1964).

89. Henley, L.C."Urinanalys is by Ion exchange,"11th Annu. Bio-Assay anr1 Analyt ical Chemistry Conference,Albuquerqua, N.M. (1965).

90. Iyer , R . 3 . and Kamath P.R."Separation of Bismuth Phosphate-Carried Actinoids by BismuthOxychloride P r e c i p i t a t i o n , 1 'Mikrochem J . , 17, 105 (1972).

91 . Buttler, F.E."Rapid Bio-assay Methods for Detn. of Plutonium, Neptunium andUranium in Urine,"Health Phys., 15, 92^ (1967).

92. Kramer, G.H. and Davies , Janet M." I s o l a t i o n of S r -90 , Y-SO, Pm-147 and Ce-144 from wet ashed Urineby Calcium Oxala te C o - p r e c i p i t a t i o n and Sequen t i a l SolventE x t r a c t i o n , "Anal . Chem., 5 4 ( 8 ) , 1428 (1982)

93 . Horwi tz , E . P . , D i e t z , M.L., Nelson, D.M., LaRosa, J . J . andFai rman,W.D."Concen t ra t ion and Separa t ion of A c t i n i d e s from Urine us ing asupported B i f u n c t i o n a l Organophosphorus E x t r a c t a n t , "Anal . Chim. Acta , 238, 263 (1990) .

94. G iacc rne l l i , R. and Spezzano, P ."Separa t ion and Sequen t i a l De te rmina t ion of Americium and Plutoniumin Urine Samples , "Inorg. Chim. Acta, 94(5), 223 (1984).

95. Veselsky, J,C., Pak Chan Kirl and Sezginer, N."The Determination of Uranium, Neptunium and Plutonium in Urine bySequential Extraction with Alamine - 336 from Hydrochloric Acidmedium,"J. Radioanal. Chem., 21, 97 (1974).

9 5. D e 11 e S i t e , A."Ana ly t i c a l A p p l i c a t i o n s of Neotr idecanohydroxymin Acid ass t a t i o n a r y phase in E x t r a c t i o n Chromatography,"J . R a d i o a n a l . Chem., 14, 45 (1973) .

39

TABLE 1

The following Table 1 summarises the bioassay procedures

reported upto 1990. The radionuclides are tabulated in the

alphabetical order and are arranged in the increasing order of

sensitivity of the method. The details furnished here are to the

best of our knowledge and the availability of literature in our

library at Indira Gandhi Centre for Atomic Research, Kalpakkam.

This table gives an opportunity to the reader to select a

suitable method by considering the sensitivity, recovery and

sequential determination either to standardise a particular

procedure or to further improve the methodology. Based on

analysis time, recovery percentage and sensitivity, the following

remarks were made in the Table 1. Screening and rapid methods

takes 30 minutes to 4 hours; Simple method takes half a day to

one full day; Satisfactory method takes one and half to 2 days;

tedious method involves many number of steps and takes more than

3 days; time consuming method takes D 3 0 days time. Poor recovery

indicates <70% ; satisfactory recovery indicates 70-90% and good

recovery indicates >90%. Minimum detection limit of a poor

3 3sensitive method is >10 mBq/dm ; sensitive method is ^1 mBq/dm

3and that of highly sensitive method is around 0.1 mBq/dm . Poor

precision indicates a precision range >10%.

4 0

Abb revia t i on s :

Preconcn.: Preconcent ra t ion ; Ref.: Reference; Solv. E x t r n . :

Solvent Ex t r ac t ion ; An. Exng. : Anion Exchange; Ct . Excng.: Cation

Exchange; E lec . Depsn.: E lec t ro Deposi t ion; TPAC: Tetra Phenyl

Arsonium Chlor ide; MEK : Methyl Ethyl Ketone; TTA : Theonyl

Tr i f luo ro Acetone; TIOA: Tri Iso-Octyl Amine; MIBK: Methyl I so -

butyl Ketone; TOPO : Tr i -n-Octyl Phosphine Oxide; TOA: Tri Octyl

Amine; KEL-F: Poly t r i f l u o r o c h l o r o e t h y l e n e ; HX 7 0 :

N'eot ridecanohydroxamin Acid .

Co-precipi ta t ions with: Sulkowich reagent; Alkaline Earth

Phosphate; cOxalate; Lanthanum Fluoride; e Fer r ic Hydroxide;

'Copper Sulfide; ^Ceric lodate; 'Potassium Aluminum Sulphate.

Extraction Chronat ograp'ny column containing: 1 . 5g of 50-

100 mesh Microthene-710 supporting 1.5 ml of 0.5M TOPO in

cyclohexane; 50% mixture of TOA and xylene on a KEL-F support;

CMicrolhene-HDEHP in toluene; d Microthene-HX 70.

41

Table 1: Preconcentration methods, analytical techniques, sensitivityand recovery of bioassay methods of various radionuclides in urine.

SI .No .

1

2

3

4

5

6

7

S

9

.1.0

11

Radio-n u c l i d e

Am-241

-do-

-do -

-do-

-do -

-do -

-do -

Cs-137

-do-

-do-

-do -

Preconcn .method

- -

aCo-pptn .

Wet Ashing,E x t r n . withHDEHP,E l e c . Depsn.

C o - p p t n . ,An . Exng . ,C o - p p t n . ,Ct . Exng .

Dry Ashing,Solv . Ext rn .with TOPO,E l e c . Dep sn .

Co-pptn . ,C t . Exng . ,E l e c . Dep sn .

Wet Ashing,El ec . Dt>psn.

Adsorp t i onon AMP,Ct . Exng .

Adsorpt i onon AMP.,Ct . i-'.xng .

Techniqueused

Direc t Count-i n g , PhoswichDet ect or

Alpha Counting

Alpha Counting

AlphaSpect romet ry

AlphaSpect romet ry

AlphaSpect romet ry

I sol opi c Diln.Alpha Spectre-met ry

Beta Counting

y-Count ing withMarine!li beaker

-do-

Low Be.taCount ing

Sens i t iv i ty ,(m Bq/dm )

(Recovery,%)

3*103

37

20(89^6%)

3 . 7

1 .8

(66_+12%)

0.8(9 5^7%)

0.143(80-90%)

(80%)

4.6*10 3

(104j+3%)

3.7*10 3

l . l * 1 0 3

(100+_3%)

Remarks

Screeningmethod

Screeningmethod

Satisfa-ctorymethod

Tedious

Poorrecovery

Sensitivemethod

Highlysensitivemethod

Satisfa-ctoryrecovery

Rapidmethod

-do-

Goodrecovery

Ref

18

18

19

20

21

22

23

24

25

26

25

42

SINo

12

1 3

14

1 5

16

17

18

19

20

21

R a d i o -nuclide

Cs-137

-do-

Plut onium

-do-

Pu-239Pu-238

P lut onium

-do-

-do-

-do-

-do-

Preconcn.method

Adsorpt i onon AMP Mats

Extrn. withdi ca rbo l l ideof CobaltAn . Exng.

Co-pptn.,Extrn. withAlamine-336,Elec . Depsn.

Co-pptn.,An . Exng.El ec . Depsn .

— — —

Rh odi zonat eCrys ta l1 i za-t i o n , d

Cc-pptn . ,An . exng. ,El ec . Depsn .

Co -pptn. ,TTA Extrn . ,El h?c . Depsn .

High Temp.A i . Exng .Batch Process

Co-pptn.

Co-pptn.

Techniqueused

Low BetaCount ing

Low BetaCount ing

Alpha Counting

AlphaSpect romet ry

Direct Count-ing PhoswichDet ector

Alpha Counting

Alpha Counting

AlphaSpect romet ry

Alpha Counting

Alpha Counting

Sensi t i v i t y ,(m Bq/dm )

(Recovery,% )

3 7

IS(97%)

(70%)

(90%)

64*10!?32*10

l * 1 0 3

(91+.5%)

740( 4 5% )

67(84S)

6 0

37

Remarks

Poor sen-s i t iv i ty

Goodrecovery.

Poorrecovery

Satisfa-ct oryrecovery

Screeningmethod

Ref .

2 7

2 8

2 9

3 0

1 8

Good 31recoveryRequi reslarge volumesof AbsoluteAlcohol

Rapid, butpoorrecovery

Screeningmethod

-do-

Screening

3 3

3 4

3 5

1 8

-do- Co-pptn.,' Alpha Counting 37An. Exng. (8 0^8%)resin f i11 er s

method

S i mp1emethod

36

4 °'

SI . Radi o-nuclide

Preconen .method

Techniqueused

Sensi t ivi ty , Remarks Ref(m Bq/dm )

(Recovery,%)

23 Pu-239 Co-pptn.

24 -do- Co-pptn . '

Liq. Scintilla- 35tion Counting. (100^20%)

Alpha Counting 13

S i mp1emethod,Poorpreci sion

Simplemethod

37

38

25

26

J. i

-do-

-dc-

Extrn. Chro- Alpha counting 11mat ography"

Co-pptn . ,Ext rn . wi t hCupf erron ,Co-pptn .

Pu-239 Co-pptns . ,Ext rn . wi thTTA

b,d

Alpha Counting

Alpha Counting

-do- '.Vet Ashing,Co-pptn . ,Ext rn . Chrp-mat og raphy

2 9 Plutonium Co-pptn.,An . Exng . ,Elec . Dep sn

3 0 Pu-2 39 Co-pptn.,An . Exng. ,El p • . [)ep sn .

31 -do- Wei Ashing,Co-pptn . ,TTA Ext rn . ,Ei ec. Depsn .

3 2 Plutonium Co-pptn.,An. Exng . ,Rlec. Dep sn .

3 3 -do- i..o-pptn. ,'An . Exng .

AlphaSpf ct romet ry

Low backgroundSolid State'Jet ect or

Alph-aSpect romet ry

AlphaSpect romet ry

AlpliaSpeciromet ry

(77%)

7.4(90%)

3.7

Alpha Counting 1.7(90+2%)

1 .3(95%)

1 . 1( 7 8% )

1 . 1(85%)

0.8(95+7%

0 .74(91%)

Satisfa-ct oryrecovery

Goodrecovery

39

40

Useful for 41largesamples

Satisfa- 42ct orymethod

Sequen- 43tial U &Pu Detn.

Sensitive 44method/Timeconsuming

Sensitive 45method

Goodrecovery

Goodrecovery

46

47

4 4

Si .No .

34

3 5

3 5

37

Radi o-nucl ide

Plut onium

-do-

-do-

-do-

Preconcn.method

Co-pptn . ,An . Exng . ,Elec . Depsn .

Co-pptn . ,An . Exng . ,HIec . Depsn .

Wet Ashing,An . Exng . ,Elec . Dep sn .

bCo-pptn . ,Ad sorpt i on on

Techniqueused

Nuclear TrackAnalysi s.

AlphaSpect romet ry

Nuclear TrackCount ing

Alpha Counting

Sensi t i v i t y ,(m Bq/dm )

(Recovery, %)

0 .6(84^14%)

0 55

0 .5(53_+25%)

0.37(89+4%)

Remarks

Time con-suming

Sensitivemethod

Poorrecovery,Time con-suming

Sensit ivemethod

Ref .

48

49

50,51

52

3 8

3 9

4 0

4 1

42

4 3

Pu-239

Radio-ruthe-nium

Ru-106

Radi oSt ron-t ium.

-do-

Sr-90

Glass Fibrefilter paper,An . Exng.,Elec. Depsn.

Wet Ashing,An . Exngs.

Fission TrackAnalysi s.

KMnO Oxdn . , Beta CountingRedn. ofRuO, to metal4

Wet ashing, Beta CountingPermanganate and Spect ropho-Oxdn., Redn. tometryof RuO. to Ru4

Ct. Exng., Beta CountingCo-pptn withRhodi zonate.Co-pptns. '

Co-pptn . asSt rontiumSulphat e

Beta Counting

Extrn. with Liq Scintilla-Dicarbollide tion Countingacid

2.1*10-3

(78+5%)

(69%)

(76+12%)

(80%)

3.7*10%

Highly 53,Sensitive 54method/Timeconsuming

Satisfa- 55ct orymethod

Poorrecovery

Tedious

56

57

Satisfa-ctoryrecovery

Rapidmethod

58

59

45

SI. Radio- Preconcn. TechniqueNo. nuclide method used

Sens i t iv i ty , Remarks Ref(m Bq/dm )

(Recovery,%)

44 Sr-90 Extrn. Chro- Beta Counting 130matography,C of Y-90 (92%)Co-pptn .

Rapidmethod

39

4o -do- An. Exng . ,Co-pptn .

Beta Countingof Y-90

74(65+10%)

Takes 14 d 60for growthof Y-90.

4 6 -do- Extrn. with Low Betadicarbol l ide Countingof Cobalt .

19(94%)

Goodrecovery

28

4 7 T c-9 9 Ammonia Sea- Beta Countingvenging potn.Co-pptn . ,Ct . Exng . ,Ext rn . withTPAC .

(50-65%) Poorrecovery

61

48 -do-

4S

5 0

53

-do-

-do-

-do-

-do-

-do-

Co-pptn.with TPAC

Co-pptn . ,Ct . Exng . ,Extrn. withMEK

Co-pptn . ,TTA E x t r n .

Co-pptn . ,Extrn. withCupferron andAshing

Co-pptn . ,An. Exng .

Beta Counting

Liq . Scint i1 la -tion Counting

Beta Counting

Spect rophot ca-me t ry withThoronol

Spect rophot o-metry withThoronol

Spect rophot o-metry withArsenazo(I I I )

(72^5%)

1.4*103

(97+2%)

100(81%)

(75%)

102(96^10%)

82(95+3%)

Satisfa-ct oryrecovery

Rapidmethod,Goodrecovery

Satisfa-ct orymethod

Sati sfa-ctoryrecovery

Poor sensitivity

Poor sensitivity

62

63

64

24

65

- 66

46

SI .N o .

54

5 5

5 6

5 7

Radi o-nuclide

NaturalThorium

Th-232

-do-

NaturalThorium

Preconen.method

Co-pptns.b > g

An . Exng.

Co-pptn.,Ashing, Ad-sorption onSi l ica Gel

Co-pptn . b ' h

Techniqueused

Spect rophot o-metry withThoronol

Neutron Activa-tion Analysi s.

Neutron Activa-t ion Analysis

Spect rophot o-metry withArsenazo(III)

Sensi t iv i ty(m Bq/dm )

(Recovery,%

6 6(80+6%)

4 1

4 . 1(80+10%)

2 . 5

, R ema rk s

)

Satisfa-ctorymethod

Tedious

Tedious

Simplemethod

Ref

6 7

6 8

6 9

7 0

58 -do-

59 NaturalUranium

60 -do-

61

62

63

-do-

U-238

-do-

Extrn. Chro- Spectrophoto-matography metry with

Arsenazo(III)

Adsorption of Fused pelletU-ArsenazoIII Fluorimetrycomplex onActivatedCarbon, De-sorption withSod .Carbo-nat e, Ext rn .with Chloro-phosponazonat e

An . Exng.

An . Exng.

Spect rophot o-metry withArsenazolIII)

Fluorimet ry

Co-pptn., Neutron Activa-Adsorption on tion AnalysisSilica Gel

An . Exng. Neutron Activa-tion Analysis

0.41(98%)

630(B7%-94%)

Rapid & 42Sensi tivemethod

Tedious

5 0 0(83^

>250

1 5 0(8 0+

1 2 5

8%)

20%)

Poor sen-sitivity

Poor sen-sitivity.

Tedious

Tedious

71

72

73

69

68

47

SI .No .

64

65

66

67

58

Radi o-nuc l ide

NaturalUranium

-do-

-do-

-do-

-do-

Preconcn.method

Ex t rn . withAl iquat -336

Co-pp tn . ,Ex t rn . withTIOA

Co-pptn. asMethyl Vio le tThi ocyanat e

Dry Ashing,Ext rn . withMIBK

Techniqueused

Fluorimet ry

Fluorimet ry

Fused pelletFluorimetry

Spect rophot o-metry withArsenazo(III)

Fused PelletFluorimet ry

Sensit iv i ty ,(m Bq/dm )

(Recovery,%)

50

25(100^10%)

25(100^4%)

25

7 . 5

Remarks

Pooi i>en-s i t :v i ty

Poor sen-sitivity

Goodr e c ov e ry

Poor sen-sitivity

Satisfa-ct orymethod

Ref

74

75

76

77

43

69 -do- An . Exng .

70

71

72

73

74

-do-

-do-

-do~

U-235

-do-

Ion Exng .

Wet Ashing

Wet Ashing,An . Exng .

An . Exng.,Membrane Sep-ara t ion withTOPO layer

An . Exng . ,Extrn. withHDEHP .

Fused P e l l e tFluor imetry ,Isotope Dilu-t ion Ma s sSpect romet ry

Isotope Dilu-t i on Ma s sSpect romet ry

Pulsed LaserE x c i t a t i on,Kinet ic Phos-phorescenceana lys i s

Thermal Ionisa-t i on Ma s sSpect romet ry

AlphaSpect romet ry

AlphaSpect romet ry

2.5 Satisfa-(75^5%)(FL) ctory(95^1%) recovery(ISDM)

78

2 .5

1 .5

77*10- 3

(85%)

1 .5*10'(92 %)

Satisfa- 79ct orymethod

Sensitive 80method

Highlysensi t ivemethod

Poor Sen-sitivity

81

Satisfa- 82ctoryrecovery

83

48

SI .Nc .

75

76

77

78

79

80

81

82

83

84

85

Radio -nuclide

U-235

-do-

-do-

-do-

-do-

-do-

-do-

Am-241,Cm-242,Cf-244.

U, Pu,Np, Pa

Th, Pu

Pu, Npand U

Preconen.method

An . Exng.on filters

Dry Ashing,An . Exng.

An.Exng,of U-Thiocyanat e,Irradiat i onof the resin

An . Exng .

Extrn. Chro-matography

Wet ashingExtrn. withTIOA

An . Exng.

Dry Ashing,Solv. Extrn.with TOPO,Elec. Depsn.

Co-pptn . ,An . Exng .

-do-

Wet ashing,Extrn. withTIOA

Techniqueused

Alpha Counting

L ow T emp. L i q•ScintillationCounting.

Delayed NeutronCounting.

Alpha Counting

Alpha Counting

Alpha Counting

Alpha Counting

AlphaSpect rometry

-do-

Alpha Counting

Alpha Counting

Sensitivity,(m Bq/dm )

(Recovery)

500(100+_30%)

300

82(80+_13%)

37(83^10%)

34(70%)

18(84^10%)

5.4(96+^3%)

1.8

(66_+12%)

11

Remarks

Poor Sen-sitivity

Poor Sen-sitivity

Poorprecision

Poor sen-sitivity

-do-

Poorpreci sion

Sensitivemethod

Poorrecovery

Sequen-tial detn.

-do-

-do-

Ref

84

85

86

87

42

19

88

21

89

90

91

49

SI .No.

86

87

88

89

SO

Radi o-nuclide

Sr-90,Y-90,Ce-144,Pm-147

U-236,Np-2.37,Pu-239

Am andPu

U, Npand Pu

Np-237,Pu-239

Precon en .method

Co-pptn . ,Extrn. withHDEHP,Co-pptn .C

Co-pptn . ,Exng. onCMPO-TBP-Amberlit eXAD -7

Ext rn . wi thDibutyl di-ethyl carba-moyl Phos-phonat e

Co-pptn . ,Ext rn . wi thAlamine-3 36

Co-pptn . ,Extrn Chro-matographyEl ec . Depsn .

Techniqueused

Low BetaCounting

High ResolutionAlphaSpect romet ry

Alpha Counting

-do-

Alpha Counting

Sensit ivity,(m Bq/dm )

(Recovery,%)

44 (100%)52 (65%)60 (87%)74 (90%)

> (90%)

(80%)(68%)

> (95%)

16(82+4%)(Np)5(73+3%)(Pu)

R ema rk s

Sequen-tial Detn

Sequen-tial &Rapidmethod

Sequen-tial Detn

-do-

-do-

Ref

92

93

94

95

96

50

Table:2 Details of Instrumentation generally used in Bioassay Programme

Counting Nuclides Nature of Background/System detected detector (Sensitivity)

Effici- Sampleency(%) preparation

«C-Count ing

a) Scint i -l la t ion

b ) LiquidScint i -l la t ion

c) AlphaSpectro-met er

d) NuclearTrackCounting

e) FissionTrackCounting

/-Count ing

a)LiquidScint i -l la t ion

b)Low BetaCounter

Gamma #Counting—

Spect ro~phot omet er

Fluori-met er

All alphaemitters

All alphaemi 11 ers

All alphaemit ters

Plut onium

Plut onium

Low energyB-emi 11 ers

All betaemit te rs

All gammaemi 11 ers

NaturalThorium,NaturalUranium

Uranium

ZnS (Ag)

PPO$

(in Dioxane)

Surfacebarri er[Si(Li)]

Solid Statetrack dete-ctor

SyntheticfusedSilica

PPO$

(in Dioxane)

GeigerMu 11 e r

Nal ( T l )

HPGe

_ _ «.

r* 0 . 08 cpm

<1 cpm

( 0 . 5 5 mBq/1)

( 0 . 1 mBq/1)

( 0 . 0 0 2 mBq/1)

7 cpm

1-2 cpm

- -

— —

(ug/ml)#

(ng/ml)#

20-30

100

,-v2

17

30-40

10-40

20-40

<5

• • •

• • •

Planchetting

Mixing thesample withcocktail

Electro-depositedplanchet

Exposure tocellulosenitrate film

Sample irra-diation in Th.neutron flux

Mixing thesample withwith cocktail

Planchetting

Planchetting/direct count-i n g

Measuringabsorbance ofmetal-reagentcomplex

Fusing withflux/Mixingliq. samplewith std.reagent

&PPO : Diphenyl oxazole, :energy emitters is possible, Sensitivity depends on the reagent blank.

Simultaneous determination of different

51

TABLE 3. ANNUAL LIMITS ON INTAKE, DERIVED INVESTIGATION LEVELS ANDDERIVED RECORDING LEVELS FOR SOME RADIONUCLIDES AS PER ICRP 54 (1988)

DAILY URINARY EXCRETION (mBq)

ANNUAL LIMIT DERIVED DERIVEDRADIO- ON INTAKE INVESTIGATION RECORDINGNUCLIDE (ALI, Bq) LEVEL LEVEL REPORTED METHOD OF

INHALATION DETECTION ANALYSISRoutine Moni- Routine LIMITStoring (after Monitoring180 d intake) (DIL/3)

Am-241 2*102(W)a N.A. -- 0.20 IDASd'23

c c c 7ftC s - 1 3 7 6 * 1 0 (W) 1 . 4 * 1 0 4 . 6 * 1 0 2 6 . 6 p - C o u n t i n g

P u - 2 3 9 2 * 1 0 2 ( W ) 0 . 4 1 0 . 1 4 0 . 0 0 3 } F i s s i o n

2 b -2 } T r a c k 54

P u - 2 3 9 6 * 1 0 ( Y ) 0 . 0 6 6 2 . 2 * 1 0 0 . 0 0 3 } A n a l y s i s

R u - 1 0 6 4 * 1 0 5 ( Y ) N . A . C p - C o u n t i n g 5 6

5 r - 9 0 1 * 1 0 ( Y ) 3 4 0 1 1 3 2 6 . 6 B - C o u n t i n g

T h - 2 3 2 4 0 ( W ) 0 . 3 1 0 . 1 0 0 . 5 7 } S p e c t r o - 4 £

} p h o t o m e t r yT h - 2 3 2 1 0 0 ( Y ) 0 . 0 4 7 1 . 6 * 1 0 0 . 5 7 }

U - 2 3 5 2 * 1 0 3 ( Y ) 4 . 3 1 . 4 7 . 5 6 S C S ' 8 8

T f 81

U - 2 3 8 2 * 1 0 ( Y ) 4 . 6 1 . 5 0 . 1 1 TIMS '

N.A.: Not Applicable, these monitoring intervals do not satisfy the

accuracy c r i t e r i o n . aW: Week Class; Y: Year Class; CDetection Limit not

reported; IDAS: Isotope Dilution Alpha Spectrometry; SC: Scintillation

Counting; TIMS: Thermal lonisation Mass Spectrometry.