p.1 

PICK-UP DATE: 

BOX 10 OF 10 

Step 2: FOR ASRC INTERNAL USE 

ONLY 

(PART A_ of_B ) 

EPA DOCKET ID: 102RQ-RN 

41) 102RQ-RN-5-3 

43) 102RQ-RN-5-5 

45) 102RQ-RN-5-7 

47) 102RQ-RN-5-9 

49) 102RQ-RN-5-11 

51) 102RQ-RN-5-13_ 

53)( 102RQ-RN-5-15J 

55) 102RQ-RN-3-4 

57) 

59) 

61) 

63) 

65) 

67) 

69) 

71) 

73) 

75) 

77) 

79) 

Step 3: FOR ASRC INTERNAL USE 

ONLY 

CD: 

OA: / 

42) 102RQ-RN-5-4 

44) 102RQ-RN-5-6 

46) 102RQ-RN-5-8 

48) 102RQ-RN-5-10 

50) 102RQ-RN-5-12 

52) 102RQ-RN-5-14 

54) 102RQ-RN-5-31 

56) 102RQ-RN-2-5-1 

58) 

60) 

62) 

64) 

66) 

68) 

70) 

72) 

74) 

76) 

78) 

80) 

Step 1: FOR ASRC INTERNAL USE ONLY 

Are there more documents for this Docket in another boxT^YE^)/ NO 

*Fill out Continuation Sheet and go to Step 2 

Internal SFUND Box Number _35_ OF 283_ 

Initials/Date: LDS / 3-8-2007 
py 

oyKA-tf^y-iy 

i 

i 

i 

j 

i 

i 

i 

r 

r 

Model* for the Evaluation of Ingestion Doses Froa tha Consumption of 

Terrestrial Foods Following an Ataospherie Radioactive Release 

'-'-'**•.- y 

' -

:

 . S. Hair- -~ 

Contents 

Approved 

Classification and Distribution 

Approved 

/ 

.$m^A V.k~ 

Head of 

Health Physics 

Research Section 

Director 

For Inclusion la Atoslndez 

II 
p.3. 

r 1 

I 

I 

I 

I 

I 

I 

i 

D 

E 

II 

II 

I! 

I 

SUMMARY 

In this report various methods are described which have been 

Incorporated in the FOODWEB module of the CECB's NECTAR environmental code 

and are currently being used within CECB to assess ingestion doses from 

consumption of terrestrial foods following an atmospheric radioactive 

release. The aajor steps in such an assessment are: 

(1) the calculation of nuclide concentration levels in various foods -

arising from a known deposition from the plume, 

(11) the calculation of the corresponding individual and population 

doaes arising from consumption of these foods. 

Of these, the first is the most complex and is achieved via *he use of 

an appropriate foodchain model. Four such models have been developed within 

CECB, namely: 

(1) a general, dynamic model covering a wide range of foodclmin 

pathways, which aay be used to study the time-dependence of radionuclide 

transfer for both continuous- and.accidental releases of mixtures of 

radionuclides in decay chains at different seasons of the year, 

(11) a simple, equilibrium model covering a limited number of foodchain 

pathways, which aay be used only for a continuous release of a single parent 

nuclide, 

(iii) two "special case" aodels, respectively for studying the transfer 

of tritium and

 ll*C froa continuous releases of trltiated water and l**C 

labelled C02« 

These aodels .are fully described and results of typical calculations 

presented. Also given are the results of a validation of the dynamic aodel 

against aeaaured

 90Sr and 137Cs levels in milk in the O.K. resulting froa 

weapons fallout. 

Finally, methods are also described ln this report for calculating 

individual and population doses -from Ingestion using the results of the model 

calculations. The population dose-calculations utilise a data base 

describing the spatial distribution of productlon'of a wide range of 

agricultural products. .The development of such a data base for Creat Britain 

is described, based on the 1972 land use and livestock census, and maps are 

presented for each agricultural product. 
P.4 

i 

I 

B 

I 

I 

a 

i 

i 

i 

i 

i 

i 

i 

r 

1. INTRODUCTION 

2. RADIONUCLIDE TRANSPORT VIA TERRESTRIAL FOODCHAINS - A SUMMARY 

2*1 Transfer to Edible Plant Matter and Animal Feed 

2.1.1 Direct Contamination 

2.1.2 Uptake from-the Soil Deposit : 

2.2 Transfer to Anlaal Products 

3. A DESCRIPTION OF THE MODELS 

3.1 Dynamic Model 

3.2 Equilibrium Model 

3.3 "Special Case" Models 

4. VALIDATION OF THE DYNAMIC MODEL 

.4.1 Fallout Data Analysis 

4.2 Saapla Calculations 

5. THE CALCULATION OF INDIVIDUAL DOSE FROM INGESTION 

6. THE CALCULATION OF INGESTION POPULATION DOSE . 

6.1 Methods 

6.2 Data 

6.2.1 Production of Agricultural Products Data Library 

6.2.2 The Food Utilisation Data 

7. CONCLUSIONS r - - -

REFERENCES 

APPENDIX 1: Mathematical Aspects of the Dynamic Model 

APPENDIX 2: Derivation of Tritium Transfer Factors for Animal Products 

(Constant Humidity) 

APPENDIX 3: Derivation of Tritium Transfer Factors for Animal Products 

(Variable Humidity) 

APPENDIX 4: The Calculation of Dynamic Itodel Rate Constants from 

Equilibrium "Transfer Data" 

APPENDIX 5: Actlnide Uptake to Animal Products (by M.D. Otis and 

J.A. Roberts, Science Applications Inc., Schaumburg, 

Illinois, .USA). 
P.5 

I 

I 

B 

I 

I 

B 

I 

I 

I 

NOTATION IN MAIN TEXT 

Symbol 

N 

Quantity Denoted 

8 

V 

f. 

\ 

P 

*s 

cs 

°R 

CSP 

~L 

I 

Vector of nuclide inventories of the various compartments of a 

coapartaent model. 

Matrix of rate constants Xj* for activity exchange between 

eoapartaents. ~ 

Matrix of conatants providing the activity input to the 

coapartaent aystea. 

Dry aatter content of plant. 

Fresh weight plant density. 

A constant such that interception fraction on plant - l-e~W* 

(Chamberlain, 1970). 

Translocation factor from foliage- to edible part. 

TOTAL deposition rate from plume, i.e. onto both plants and 

•oil. 

Radioactive disintegration eonstant. 

Field loss coefficient. 

^Activity concentration per unit weight of edible plant part 

froa surface contamination only. 

Density of wet soil; 

Depth of ploughed layer or rooting zone (as appropriate). 

Rate constant for activity removal out of ploughed layer/ 

rooting zone to deeper soil layers. 

Activity concentration per unit wet weight of soil. 

Activity concentration per unit weight" of edible plant part 

from root uptake only. _ • _. _. - _ 

Soil tp plant concentration factor.. 

Transfer factor relating equilibrium concentration ln edible 

plant part to unit deposition or air concentration. 

Mean storage time of food, between its production ln the field 

and-its consumption. 

Activity concentration per unit weight of animal feed L. 

Total daily activity intake by animal. 

Activity concentration per unit weight of animal product A. 
P.6 

Symbol Quantity Denoted 

J. Dally animal intake of feed L. 

fA Equilibrium dlet-to-anlaal product concentration factor for 

animal product A. 

fp. Hydrogen content by weight of food 1. 

FH Hydrogen content of surface air.. 

H Absolute humidity. 

jr.. Equilibrium air concentration of pollutant. 

*water Equilibrium soil water concentration of pollutant. 

r. Ratio of equillbrlua pollutant concentrations ln equal volumes 

of soil water and air. 

Bj. Anlaal breathing rate. : _ 

W ^ Daily water Intake by anlaal. 

IQ± Carbon content by weight of food 1. 

Fc Carbon content of surface air. 

• 

t\t_ Coaaltted dose to organ k froa one year's Intake (or one day's, 

depending on context) of^nuclide J in food 1. ~ 

C^. Activity concentration of nuclide J~ in food 1 at eonaumptlon. 

dt Dietary Intake rate of food'-i. 

J k ' • -" •: " . 

Dj Coaaltted dose to organ k-fran ingestion of unit activity of 

nuclide J - the ingestion dose-intake factor. 

Hjik Committed dose to organ k from intake over all time of nuclide 

J in food 1. 

H. Committed dose to organ k from Intake over all time of all 

nuclides In all foods. ~ ._'"""-" 

c^. Integrated activity of nuclide j in animal product 1 corrected 

for radioactive decay between production and consumption. 

S^ju^ Coaaltted population dose to organ k from intake of nuclide j 

in one.year's production of food 1 produced at location Jt. 

x ^ . Total annual production of food 1 at location 1. 

F^ Fraction of annual production of food 1 that is consumed by the 

population (as opposed to going to animal feed or seed, for 

example). 
P.7 

1 

I 

I 

1 

1 

B 

B 

a 

1 

B 

Symbol 

• 

C

i j l 

k 

• -•- _ 

• 

B 

a 

Quantity Denoted 

Activity concentration at conauaption of nuclide j in food 1 

produced at location 1. 

Coaaltted population dose to organ k froa intake of all 

nuclides ln all foods produced at all locationa over one year. 

1 

I 
P.8 

I 

I 

I 

B 

1 

I 

\ 

I 

I 

I 

I 

i 

! 

! 

I 

I 

i 

1. INTRODUCTION 

All radioactive aaterials which are present in the environment may enter 

foodstuffs to some extent thus constituting a potential source of radiation 

expoaure to man. However, the extent to which this process occurs may vary 

by many orders of magnitude depending on the physical and chemical 

characteristics of the radioactive materials and on the location -and- rate at 

which they are Introduced into the. environment, the transfer processes being 

known collectively ao foodehaina. 

In the case of atmospheric radioactive releases, the significance of the 

terreatrlal foodchain pathway aa a potential route of exposure is usually 

assessed ln relation to other exposure routes such as, for exaaple, 

inhalation and external exposure froa airborne and ground deposited activity. 

Central to the estimation of the ingestion dose- is.tha need for a foodchain 

transfer aodel relating activity deposition to levels in foodstuffs. Many of 

the aodels developed initially were aiaple equilibrium aodels considering 

only a saall nuaber of critical foodehaina. An example of such a aodel used . 

within CEGB and incorporated ln the POPFOOD computer code is given by 

Nair et al (1980). Since such aodels relate only, to equilibrium conditions, 

they are only suitable for the assessment of annual doses froa continuous 

releases and are unsuitable for assessing doses froa accidental^releases. 

For this reason a considerable effort haa recently been expended both within 

CEGB and outside, Into developing tiae-depeodent aodels and associated data 

"covering a whole range of foodchain pathways suitable for assessing doses 

froa both continuous and accidental ataospherie releases. 

In this report, a full description is provided of.the various foodchain 

aodela currently in use within CECB. These consist of: 

(1) a dynrmlc foodchain aodel encompassing a wide range of foodchain 

pathways applicable to the assessment of doses from both continuous and 

accidental releases, - : 

(11) a simple equilibrium foodchain model, which encompasses only a 

limited number of foodchain pathways, applicable Just to the assessment of 

doses from continuous releases, which is included for historical- reasons,. 

(ill) two "special case" equilibrium foodchain models applicable to the 

assessment of doses from continuous releases of *H as HTO and l^C aa CO., , 

respectively. 

All the models have been incorporated in the NECTAR-F00DWEB module of 

the CEGB'* NECTAR envlronaentsl code. The production of standard library 

data for the models is described In this report (Appendix A), while results 

- 1 -
P.9 

of an axparimantal prograaaa to provide key data for the dynamic foodchain 

aodel will ba presented elsewhere (Grogan et al, 1984). The processes 

whereby radioactivity Is transported through terrestrial foodehaina are 

summarised in Section 2, while th* aodels are described fully in Section 3 

and coapsred with experiaental data in Section 4. Finally, methods for 

calculating individual and population dose* are described in Sections 5 and 6 

and the conclusion* are presented ln Section 7. 

2. RADIONUCLIDE TRANSPORT VIA TERRESTRIAL FOODCHAINS - A SUMMARY 

The transfer mechanisms involved in terrestrial foodchain transport arc 

depicted schematically in Figure 1. Uptake into crops and anlaal products 

are discussed separately below. 

2.1 Transfer to Edible Plant Matter and Anlaal Feed 

There are two distinct route* of uptake of radionuclides into crop* and 

livestock feed. The** are dlreet contamination via aerial deposition and 

uptake froa the *oll deposit, and are considered ln turn. 

2.1.1 Direct Contamination 

The .extent to which deposited aaterials are retained oa plant* depend* 

on the physical characterlatlcs of the deposit and on the growth fora of the : 

plant. Radioactive material* may be deposited aa particle*, vapour* or a* 

aolutions ln rain or fog. Particles exceeding 45u diameter (AMAD) are rarely 

retained on leave* as they usually rebound froa the surfaces to reach the 

soil.. As the particle .size decreases, the retention increases, being 

typically ~ 15Z for 4u AMAD particles depositing on, say, 4" high pasture. 

At the .other end of the AMAD range, the deposition of fine particles and. 

vapours is largely determined by diffusion processes since they have a very 

low terminal velocity. The deposition is greatest on leaf edges where the 

laminar boundary layer of still air is smallest. The degree to which 

solutions will deposit depends on the quantity of water deposited and on the 

droplet alze. Typically, about 25Z of a deposit of ~ 100u AMAD droplets will 

be_ retained_on 5" high pasture. Thus, ln general, the fraction of the 

deposit-retained on foliage will depend principally on the following 

-factors: 

(i) Physical and cheaical fora of the deposit. 

(ii) Type Df plant. 

(ill) Herbage density and its distribution [i.e. whether uniform 

(grasses) or non-uniform (cultivated crops)]. 

The direct surface contamination of leaves aay, ln time, lead to tissue 

contamination of the edible part of the plant, this process being called 

- 2 -
P.10 

I 

I 

B 

I 

I 

I 

"translocation". The eignlfleance of translocation will, ln general 

(although not exclusively), Increase the earlier in the growing season the 

deposition occurs. In addition, the edible parte, auch aa the ears of grain, 

aay be contaminated directly. Uptake into the edible parte aay alao occur 

via absorption of surface contamination froa th* basal parts of the plant. 

This process is called "plant base abaorptlon". 

Surface contamination is also readily lost froa leaves.by.processes such 

as washoff and the scaling of wsx froa leaf surfaces. The processes are 

known collectively as "field loss" and coapete with translocation a* a aource 

of depletion of surface activity froa herbage. The rate of field loss is 

dependent on the season of yesr and on plant type and aay also depend on the 

physical and cheaical characteristics of the deposit and on the. climatic 

condition*. : 

2.1.2 Uptake from the Soil Deposit 

Uptake froa. the soil deposit occurs via root uptake and *oil 

resuspension* The. extent of root uptake depend* on tha type of plant, the 

soil on which it ia grown, the season of the year and the radionuclide under 

consideration. Substances always enter the plant as labile ions and the 

absorption mechanism consists of an initial rapid Influx across the root 

membrane followed by transfer to, and upward movement in, the vaaeular 

tlaaue. The first process is initially (< 10-15 Bins) very rapid but 

subsequently falls to a steady, lower level. The .second and third processes 

are directly dependent on the utilisation of energy released by respiration. 

Soae important factors affecting the rate of absorption are: 

(1) Ionic concentration. The absorption rate varies directly as 

concentration at levels low compared to the threshold for saturation and 

reduces as the saturation level is reached. 

(11) Ionic valency. High valency ions are known to diffuse 

preferentially, into the root exterior but the vascular tissue absorbs, 

preferentially, iona of low valency. _ 

(ill) Soil pH and the presence of alneral and colloidal particles. An 

alteration in pH can cause precipitation of ions with a consequent drop ln 

root uptake. The presence of mineral and colloidal particles or of- humle 

materials can also reduce the uptake of certain nuclides, such as isotopes- of 

caesium, by the "soil fixation" mechanism. This effectively removes-ions . 

from the labile soil pool, for example, by fixing them in the lattice 

lnterstltials of mineral particles. 

(iv) Interrelationships between ions. Interrelationships occur when the 

rate of uptake of one Ion depends on the concentration of another Ion. A 

- 3 -
P.11 

veil known example relates to the uptake of strontium, which lncreaaea with 

decreasing calclua concentration in the soil. 

Tha significance of root uptake may alao ba affected by other factors 

such aa crop productivity and agricultural practice, ln particular the uaa of 

fertilisers and ploughing/direct drilling practices. 

Data on soil reauapensloh are sparse ln comparison to data on root 

uptake. The soil content of above ground part* of plant* arise* froa two 

separate sources: 

(1) direct resuspenslon of soil particles froa the' ground below, for 

exaaple, by ralnsplash, 

(11) Interception by the above ground parts of soil particles present as 

dust ln air blow ln froa surrounding areas. 

In addition, special harvesting technique* auch a* the use of coablne 

harvesters may"be expected to Increase the soil content of the harvested 

crop. A higher soil content aay-alao be expected ln the akin* of potatoes 

and rr<t vegetables which, although not arising froa any resuspenslon 

•echnnisa, needs to be taken into account when calculating total activity 

concentratlona. 

2.2 Transfer to Anlaal Products 

Theniptake of activity/by aniaals and Its transfer to anlaal products is; 

essentially a two atep process. The Inhaled or Ingested activity is 

initially transferred to blood, and lymphatic fluid which< in turn, gives rise 

to~ contamination "of milk and meat. The air passages consist of the nasal 

cavity," pharynx, larynx, trachea and the bronchi* The latter subdivide into 

alnute round *ir sacs called alveoli where exchange of carbon dioxide and 

oxygen between circulating.blood and air occurs. Thus, the iaportant 

physical/chemical factors affecting uptake via inhalation into body fluids -

are particle size, solubility and cheaical form, while the l«tportant 

physiological lectors are^breathing rate and efficiency of mucosal and nasal 

clearance. 

-.. The.gastro-lntestlnal,tract (GI tract) Is divided into the stonach, 

small Intestine (SI) and the large intestine (LI). The LI is Itself divided 

into the cecum, colon and rectum and the SI into the duodenum. Jejunum and 

ileum. Additionally, for ruminants, ehe stomach Is divided into the rumen, 

reticulum, omasum and abomasum. Gastric Juices and other digestive enzymes 

are added in the stomach but absorption of radionuclides into blood occurs 

mainly from the walls of the SI. The important physical/chemical factors 

governing the uptake are thus solubility and chemical fora while the anlaal 

diet Is the major physiological factor. 

- 4 -
P.12 

I, I 

I i 

• 

B 

I 

l| 

l| 

l i 

1 

Il ' 

I 

I 

I 

111 

I 

I 

I 

I 

I 

In aany cases, the ingestion pathway is aore significant than the 

Inhalation pathway for animals. The diet of most livestock consists of 

graaa, hay/silage and straw together with a saall but non-trivial amount of 

•oil Ingested directly with the grass and the atored feed. The ingestion of 

stored feed can give rise to complications ln the foodchain tranafer 

calculations. For example, a release of a long-lived radionuclide in the 

grazing aeaaon can give rise to continuing high level* In the anlaal product 

well after the grazing, aeaaon has ended owing to the continued consumption of 

contaalnated feed grown in the grazing season. However, this would not be 

the ease for a ahort-lived radionuclide, which would have decayed away during 

storage of the feed. 

A classical reference giving a general review of radionuclide transport 

through terrestrial foodchain* is-provided-by Scott Russell (1966). Although 

auch detailed inforaation has subsequently become available (e.g. Coughtrey 

and Thome, 1983), aany of the general discussions in that reference are 

•till valid. 

3. A DESCRIPTION OF THE MODELS 

Model* currently ln use consist of: . 

(1) a dynamic foodchain model allowing calculations to be made of the 

time course of radionuclide tranafer through a wide range of foodchain 

pathways, 

(ii) an equilibrium foodchain model.encompassing a Halted nuaber of 

foodchain pathways applicable, by definition, only to well characterised 

situations for the assessment of doses from continuous releases, 

(ili) two "special case" models applicable to the assessment of doses 

froa continuous releases' of

 3H aa RTO and lH C as C02> 

This range of aodels haa been Incorporated into the NECTAR-FOODtfEB 

aodule of the NECTAR environmental code for several reasons. For example, 

the advantages of using the equilibrium models are. that: (a) they are 

relatively simple ln concept and therefore easily understood, and (b) since 

they refer to an equilibrium condition, they may be .used to produce's small 

set of static transfer coefficients, each specific to a given nuclide and. 

food. The disadvantages are that: (a) by their very nature they may give 

rise to unnecessarily pessimistic results for those radionuclides that do not 

reach equilibrium during the course of the release, and (b) since they only 

cover a limited number of foodchain pathways, they must be used with care 

only lu well characterised situations where neglect of the extraneous 

pathways has been Justified. 

- 5 -
P.13 

The dynamic model covera releases of all nuclides except *H and

 l-c. 

Dynaalc aodels have not been developed for these two nuclides since 

time-dependent data are not at preaent required for ^H and

 l**C releases I 

within CEGB. Advantages of ualng such aodel* are that: (a) they are very 

general ln nature and therefore do not require decision* to be aade in I 

advance as to which foodchain pathways are significant and which are not, 

(b) they can be used to study the behaviour of nuclides ln a decay chain (cf. -

actlnldes) rather than just of a single parent nuclide, and (e) since they 

•re tiae^-dependent in nature, they perait studies to be made of the Influence 

on ingestion dose of the season of year when the release occurs. The aajor 

disadvantage 1* that, by their very complexity, they require a large 

supporting data, base which Is difficult to collect and.validate. 

The various models are described in turn below. 

3.1 Dynaalc Model 

The dynaalc aodel consists of two aub-aodels, one for crop* and the _ 

other for anlaal products. These are ahown schematically ln Figures 2 and 3 

respectively. The aodel for crops considers the folloving processes: 

(1) field loss froa foliage to soil and plant base, 

(ii) translocation of aurfaee activity to tissue, 

(Hi) plant base uptake, 

(lv) root uptake froa the ploughed layer and froa a deeper: soil zone, 

(v) nuclide fixation ln soil, - -

(vl) movement of the labile component down the soil column, 

(vii) soil re8uspenslon onto edible parts, y -. -

(vlll) changes ln edible part concentratlona. arising from dilution (or 

concentration) during food"processing and froa radioactive decay 

between harvest and consumption. ' 

The "plant base" compartment haa been Included only for possible use ln 

the context of uptake into graaa and cereals and-is normally zeroed out of 

the calculation. Similarly the compartments for fixed soils have been 

Included only to account for the behaviour of certain elements (eg. caesium 

ln clay soils) and are not normally used'. The.model assumes, ." 

pessimistically, similar activity levels for both edible and nou-edlble parts 

for surface contamination of leguminous green vegetables and cereals, in lieu 

of aore discriminating data. The total concentration at harvest in green 

Vegetables, fruit and cereals is taken to be the sum of the inventories in 

the surface and tissue compartments together with a component from soil 

resuspenslon. The corresponding value for root vegetables Is taken just to 

be the tissue Inventory together with a component for soil content. 

- 6 -
P.14 

I 

B 

1 

B 

I 

-i 

The aodel for anlaal products considers the same processes (l)-(vill) 

above for uptake into graaa and straw. However, translocation of activity 

from surface to tlaaue la not considered owing to a lack of data and all 

appropriate rate conatants are zeroed. All feed Is assumed to be produced 

and consumed ln situ. Grass Is assumed to be consumed continuously in the 

grazing season, while radioactive decay of atored atraw prior to consumption 

is taken Into account. Levels in hay/allege are coaputed from levels in 

grass ualng appropriate scale factors for their respective dry matter 

content, and radioactive decay in atored hay/sllsge Is also considered. .The . 

animal diet is assumed to consist of specified levels of grass, hay/silage 

considered together, straw and aoil, the soil being assuaed to be consuaed at 

the same time as the grass. A one-coapartaent aodel is assumed for tranafer 

of activity froa feed to anlaal product and the aodel also accounts for -

changes in anlaal product concentratlona arising froa food processing and 

froa radioactive decay during storage. All anlaal products are assuaed to be 

produced continuously. Thus, for the case of, say, beef, the age 

distribution and size of herd are assuaed to be eonstant with the culled 

aniaala being assuaed to be replaced by an equal nuaber of young aniaala. 

The aodel does not, at present, consider anlaal Intake of activity via 

Inhalation although it la recognised that this could be a potentially 

iaportant exposure route for soae-special cases. 

Mathematical aspects of the dynaalc aodel are considered In detail ln 

Appendix 1. The model can consider the 74 actinides and 425 fission products 

Incorporated ln the NECTAR code either together or separately and, in the 

ease of fission products, calculations can be restricted only to those mass • 

chains of interest to the user. These features are specified in detail by 

Nair (1982). The conceptual stages of the calculation are as follows: 

(a) Model for crops: The Inventory of each nuclide ln a decay chain in each 

compartment of the plant-soil model (illustrated in Figure 2) is specified by 

a set of coupled linear first order differential equations. These are- ---

specified fully in Appendix 1 and are of the form: 

where £ is a vector of nuclide inventories per unit weight of material In the 

various compartments, [c ] is a matrix of constants that are proportional to 

the deposition rate over a given time step and [\] is a matrix of rate/decay 

constants. The latter is a stiff, sparse matrix and the equations are solved 

numerically upto the required time using techniques especially suited to such 

- 7 -
aatricea. The concentration per unit veight in the crop at harvest is then 

calculated aa follows: 

(1) Green vegetables/fruit/cereals: Sua of Inventories in surface and 

tissue compartments together with a component from soil 

resuspenslon. 

(11) Root vegetables: The tissue coapartaent Inventory together with a 

component for soil content. 

The component froa soil is obtained by sealing:the total concentration 

in soil (labile + fixed) at the end of the integrated step by a factor 

specifying the resuspended soil content of the crop. 

The final step ln the calculation accounts for radioactive decay between 

harvest and consumption, the equationa for" radioactive decay in a decay chain 

being solved analytically. A factor can also be- applied-to account- for 

activity loss or concentration during food processing. 

(b) ; Model for animal- products: The calculation of nuclide concentration 

levels in anlaal products (Illustrated in Figure 3) proceeds as follows: . 

(1) Calculation of level* ln grass, hay/silage and straw. 

(11) Calculation of anlaal activity intake rate (although this can also 

be Input directly by the user without resort to calculation (1)). 

.(ill) Calculation of level in anlaal product. ~ y 

The levels in graaa and in straw are calculated exactly as described 

above for crops using separate plant-soil aodel parameters for each. The 

level in grass Is not subject to a radioactive decay correction aa it Is 

assumed to be consumed in the field. However, the levels in hay/silage and 

straw are corrected for both radioactive decay and mass compaction during -

storage. The Initial and final concentration values ln each feed at the 

beginning and end of each time step are then averaged to provide approximate 

eonstant concentration values over the time step. These are then uaed, in -. 

conjunction with assumed dietary intake rates by livestock of grass, 

hay/silage and straw, to calculate the total intake rates over the timestep 

from these feeds.- An additional input is also provided from direct 

consumption of soil by the animal. The soil Is assumed to be consumed 

primarily during outdoor grazing and hence appropriate levels are computed 

from the inventories of the labile and fixed soil compartments.of the. model 

for grass. 

The calculations of total dietary intake rates made above are input to 

another system of differential equations also of the form: 

- 8 -
P.16 

r.. 

I 

I 

I 

B 

I 

1 

* - [X] N+ [c], 

where IT is a vector of nuclide concentrations per unit weight of the animal 

product, [c] is a matrix of nuclide Intake rates by the anlaal via its diet 

and [x] is a matrix of metabolic rate/decay constants* These are also solved 

numerically over the name time step aa pertained for grass (a different time 

step ia allowed, if required, for hay/silage) and the final eoneentration in 

the animal product at consumption is calculated taking into account 

radioactive decay and activity loss/concentration during processing. 

3.2 Equilibrium Model 

The equilibrium model consists of two sub-models, the one for crop* and 

the other for animal products. Only parent nuclide* are considered and the 

two. sub-aodel* sre fully described below. 

(a) Vegetable crops/cereals/fruit 

Foliar uptake: At equilibrium the rate of deposition of activity onto 

the crop will be equrl to the rate of loss of activity froa the crop. 

Chamberlain (1970) haa shown that the fraction, p, of deposited activity 

intercepted by the plant is given by:-

p.i^ V " :•::; - '; 5 . 

-where.u is a constant and g and V denote the dry aatter content of the plant 

and the crop-density expressed aa fresh weight per unit area of land. Thus 

the rate, d'-, at-which activity Is depositing on the plant, expressed as an 

activity concentration rate per unit fresh weight of the plant, la given by:-

- d- - £ (i->*V. y 

where f denotes the translocation factor at equilibrium from foliage to the 

edible part of the plant and u the total deposition rate. Similarly the rate 

of activity loss,' 1', from the plant is given by:-

r

-(VVcF» 

where K_, X and C_ denote the radioactive disintegration constant, the field 

loss coefficient and the required equilibrium concentration of activity per 

unit weight of edible plant. At equilibrium, d' - V so.that C_ is given 

by:-

- 9 -
P.17 

'[(VV" J"" 

Root uptake: At equilibrium the rate of deposition onto soil will equal 

the rate of.activity loaa from the ploughed layer. If transfer of activity 

froa~ foliage to soil via field loaa is ignored, the formerr expressed per 

unit veight of vet soil, is given by:-

•m b>> 

since a fraction e_W* of the depositing activity lands on the soil. The -

quantities p and X denote the denaity of vet soil and the depth df the 

ploughed layer. 

If nuclide fixation ie ignored and removal of activity froa soil to 

plant Is assuaed to be saall in comparison to removal froa the ploughed 

layer, the rate of activity loss is given by:-

r-<Wcs-

-where Xg denotes the removal rate froa the ploughed layer to deeper aoil 

zones and Cc denotes the required activity concentration per unit wet weight 

of aoil. At equilibrium d" - 1" so that C is given by:-

s

 «v w • 

The concentration per unit weight of.the edible part of the plant via root 

uptaker C^, ia. then given "by:-

C - C C-. 

R SP V 

where C denotes the equilibrium soil-to-plant concentration factor. 

Transfer factor calculation: The required factor, a, relating total 

activity concentration in the edible part of the plant to a unit deposition 

rate is then given by:-

- 10 -
P.18 

J 

B 

I 

I 

where the factor e~ a S accounts for radioactive decay during food storage. 

The expression does not account for any contribution from soil resuspenslon 

onto the edible part of the plant. However, floral uptake, which occurs In 

grain crops, is accounted for by increasing the translocation factor f_, 

while plant base uptake 1* accounted for by increasing the soil-to-plant 

concentration factor C__. 

SP 

(b) Animal, product* 

The aodel for anlas1 products considers anlaal intake of grass, 

hay/silage and straw (but not soil). These are all assisted to be produced 

and consuaed ln situ and the transfer factors (denoted by a.) are calculated 

using the expression for a derived above with f - 1^ l.e^ JIO discrimination 

is assuaed between edible and non-edible parte. The anlaal feed 

contamination level, C_, Is then given by: 

where a. is the transfer factor for feed L and takes Into account decay and 

aaaa compaction during atorage for hay/silage and straw. The total animal 

Intake rate, I, la then given by: " 

I 

I 

I 

I 

i5.p L c L -„iJ L V .-••:_ - ;- - A 

where J, is the Intake rate of feed L. At equilibrium, the concentration ln 

the animal product, C , is given by: 

CA-fAX"VpLV y" 

where f. denotes the equilibrium dlet-to-animal product concentration factor. 

The animal product transfer factor, a, Is then given by: 

" £ ^ ^ " [*k.]•< «L>]

 e'Vs' 

where t. denotes the mean animal product storage time. The complete 

expression for a Is thus obtained by substituting for the OL and is given 

by:-

- 11 -
P.19 

a - t n^""* A^:m'

v

'\( J + -£ e 

8 «h 

1-e 

-•*8S'WS -»«S'WS' 

'SPS' 

'S' (W) w s'

 (W pA

P 

-Vss'] "Vs 

e I e , 

where subscript* g, hand S' refer to graas, hay/silage and atraw 

respectively. 

(c)'• Transfer Factor Calculations 

131.133. 

89 90 134 137 

' Sr and ' Cs are Hated ln Table 1. Also given are transfer factors 

Result* of Illustrative tranafer factor calculations for 

• 13 

14. for tritium and * C, which are considered In section 3.3-belov. Transfer 

factor* for allk .are quoted for both aa annual average cow diet, which 

includes coneuaptlon of stored feed, and for a aore pesslalstlc diet 

consisting solely of grass all year round. The data oa which the 

calculations are baaed are listed in Table 2 and constitute part of the 

standard-data library to be used with the F00DWEB aodule. It 1* seen that 

l33I is transferred to any significant extent only to liquid allk, owing to 

its short assuaed storage time oi Juat one day. Similarly

 l3lI is 

transferred preferentially to allk although high transfer factor* are also' 

observed for green vegetables and cereals. In -the case of the latter, a -

lower transfer factor would arise if the cereals were to be stored for a 

. 89 90 longer period than 30 days. * Sr are transferred preferentially to 

cereals although high transfer factors are also observed for allk, eggs and 

green vegetables. For the case of ' Cs, the transfer factor is also 

highest for cereals closely followed by milk and beef. 

The above results illustrate the importance of considering a range of 

food produces when assessing ingestion doses from generalised radionuclide 

releases. 

3.3 "Special Case" Models 

The two "special esse" models relate respectively to the transfer of 

tritium and

 ll*C In terrestrial foodehaina for continuous releases of these 

nuclides ln the chemical forms RTO and COj. The transfer, of these two 

radionuclides is more complex primarily because of the fundamental roles 

played by hydrogen and carbon in the ecological cycle. For this reason, the 

most commonly used model (e.g. CEC, 1979.) is highly simplistic in nature and 

utilises a specific activity approach. The activity of tritium (or

 ll*C) per 

- 12 -
9 • 

P.20 

I 

I 

B 

1 

B 

B 

I 

unit aass of hydrogen (or carbon) in huaan tissue is assuaed to be equal to 

that ln air. Since the standing level in air is known, the organ and 

effective doae-equivalenta can be calculated accordingly. This assuaption is 

perfectly valid for the calculation of doae* froa global circulation. 

However, it la highly unrealistic for the assessaent of "first pass" dose* 

froa the overhead plume since it sssunes that the individual is permanently 

located in one spot and derives all his food ln situ. In order to overcome 

this crltlclsa a variant on the specific activity approach haa been developed 

•nd 1* Included in the FOODWEB aodule. 

The alternative approach assumes, as a starting point, that the specific, 

activity of hydrogen (or carbon) in all plant tlaaue equals that ln air where 

the plant is grown. Since different crops have differing hydrogen/carbon 

content, this laaedlately allows a. range of transfer factors to be derived 

relating levels ln the crops to levels in air where the crops are grown. 

Slallar tranafer factors may alao be derived for anlaal feed - grass, 

hay/allege and straw. These are then uaed, in conjunction with dietary 

Intake and breathing rate data for the livestock, to determine the specific 

activity ln the total intake of hydrogen (or carbon) by the livestock froa 

all pathways, which is then assumed to equal tbe specific activity in the 

anlaal product. Knowledge of the hydrogen/carbon' content of the anlaal 

product together with the aaauaption that all anlaal feed is produced in situ 

then allows the calculation of corresponding transfer factors relating the . 

level ln the anlaal product to the level ln air. = 

The two aodels are fully specified below. It Is emphasized that they 

aay only be uaed for the computation of doses from continuous releases, when 

equilibrium haa been established. No dynamic model exists, to the author's 

knowledge, for the assessment of time-dependent doses from **% releases while 

a dynamic model for tritium releases has been developed by McKone and 

Kantenberg (1978). 

(a) Tritium 

Tritium exists ln both organic and Inorganic forms ln animal and plant 

tissue. The inorganic component, which is held ln the tissue water, rapidly 

reaches an equilibrium level for a continuous release at a constant rate. 

The rate constants typically range, from about 0.1 day"1 for humans to about 

0.5 hr~l for plants, the exact value ln each case also depending on external . 

environmental factors such as- temperature, humidity and time of day. 

However, hydrogen bound to carbon is less labile than hydrogen bound to 

oxygen, so that tritium exchange between the organic and inorganic 

- 13 -
P.21 

eoapartaents occurs at a slower rate. For example, typical rate conatanta 

for organically bound trltiua ln aniaala H e ln the range 10"3 - 10"2 day""* 

depending on the tissue or organ under consideration. About 20 - 30Z of the 

tritium is organically bound in planta, this figure being typically about 10Z 

in animal soft tissues. There is Halted experiaental evidence to indicate 

that, at equilibrium for a chronic, constant intake, the organic and 

inorganic coapartaent* hav* the saae specific activity, i.e. the same 

activity of tritium per unit mass of hydrogen (Elwood, 1971; Evans, 1969). 

Tranafer Factor Derivation 

The:trltiua concentration, C., in green vegetable, fruit, cereal ot 

aaiaal feed 1 is given by: 

C i *air _ — . «_ , 

Hi H 

vhere C. 1* ln units of Bq.kga"1, v . denotes the air concentration in units 

of Bq.a"3, f_. is the hydrogen content by veight of food 1 and F_ Is the 

nl H 

hydrogen content of surface air ln unit* of kga.a**3. The latter 1* related 

to the absolute humidity, B, in units of kilograms of aoisture.a"3 air, by 

the relation: 

F„ - 0.111 H, 

vhere 0.111 is the hydrogen content of water by weight. Substitution of the 

second equation into the first leads- to the following expression for the 

transfer factor, a , in units of —°*_° ^ : 

1 Bq.a air 

A .

 fHi 

?* " *air " °- m H .-"_'- • 

Trltiua levels ln root vegetables are assumed to be in equilibrium with 

* 

the level in the soil water so that the concentration C. in root vegetable j 

is given by: 

In general, uptake of tritium into plants occurs both directly from the 

atmosphere via photosynthesis and from tritium contaminated soil water. If 

the latter Is not diluted by runoff of uncontamlnated water, then the soil 

water tritium concentration will ln time equal the rainwater concentration. 

The levels ln the above ground parts of plants will then be intermediate 

between the atmospheric water and rainwater levels while the levels in below 

ground parts will closely follow the latter. 

- 14 -
P.22 

I 

B 

Vater

 T \lt 

111 " H i ' 

where r_ t _ denotes the soil water concentration in units of Bq.m"3 and r 

denotes the ratio of tritium concentrations in equal volumes of soil water 

and air. 

The tranafer factor a., in .units of TM * "^ , is thus given by: 

J Bq.m air 

The tranafer factor a., for the k animal product of the 1 . anlaal, in 

B A kff»^* ^"^ 

units of TM * "T • , is shown in Appendix 2 to be given by the relation: 

Bq.a'^air 

gHki ^ i 4 oaTT-H f <J Lf HL>l 

«kl • 0.111 (Wt + 2 Bl H ) + £ (JL f^ ) • 

all syabol* and units being defined in Table 3. The transfer factor accounts 

for inhalation, skin abaorptiou and ingestion of HTO by-terrestrial animals. 

The Influence of Humidity Frequency Distribution's: 

The above expressions for the crop and anlaal product transfer factors 

a. and a. . aay be modified to account for annual variations in absolute . 

humidity. If F(H) denotes the probability of the absolute humidity being 

greater than or equal to H and o(H) denotes the appropriate transfer factor 

at a humidity level H, then the weighted mean transfer factor <ct> is given 

by: '-:' "•'.' . 

<* • /«"> I3PI «• 

The Meteorological Office has published probability distributions of absolute 

humidity for various sites ln the UR (Climatological Memorandum 103, 1976)-. 

The distributions msy be approximated by a histogram, I.e. 

- 15 -
P.23 

F(H) - FL - I for B > ^ 

• 

a* 

-

P

2 

• 

• 

F~ 

rv 

• 

• 

F • 

a 

m 0 

for 

for. 

for 

H 

H 

H 

> H 2 

> H 

. r -

> H . 

n 

Thus, for this case, the weighted aean transfer factor is given by: 

a—1 » - • 

•l .

 Hr+1 V L 

<e> - Z fcp r~ ) I c(H)dH. 

r-l .

 Hr+1 %•' L 

^ ' -

1

 " V:'' ..-_'-•-

Substitution of the derived expression for a. into the equation above gives 

the following result for the aean transfer factor for fruit, green 

vegetables, cereals and anlaal feed: 

f_. n-i F - F . H . 

<«<> -dir ^ «r^ » ?«-£»•-: 

The trensfer factor, a., for root vegetables is-unchanged since it is only 

dependent on soil water-concentrations. However, the aean transfer factor 

<ak. > for the k product of the 1 anlaal is shown in Appendix 3 to be 

given by the relation: 

, ^ r fHklffJL

fHL> j'^/r- k „ ,Vl < . 

<Ctkl>

 ' ^0.111 10.111 W, +X(JT f- )JI

 E

,

 (H^, - H > l n ("H_ _ ) + 

1

 1 tx. L.;--HL_.J r-l r+1 r r 

*„*.* w, n-l ~ F - F_^,"~ a.Ill W, + X(JTfm ) • 0.222 Bray. }]. i Hkl 1 , . t-yt r»lx-'in- f - I Lv

 L HL/ 1 rf 1' J 

«0.1ll Ul + £» t V'-t-i. -

 HrH " V fl

-

UI

_

Wl + £(JLfHL> * °'222 BlH

r 

(b) **c 

The transfer factors for

 lvC are calculated similarly to those for 

tritium. The

 l**C concentration, C., in cereal, fruit, green/root vegetable 

or anlaal feed 1 is given by: 

C i *air 

E — " "F - • 

Ci c 

- 16 -
P.24 

I 

B 

B 

I 

where C. is in units of Bq.kgm-1, % t denotes the air concentration in units 

of Bq.m-3, f . is the carbon content by weight of food 1 and F denotes the 

Cx C 

carbon content of surface air ln units of kilograms.a"3. The required 

transfer factor, cu, in units of 

Bq.kgm-i 

is then given by: ^ Bq.m

 J air 

Xalr 

LC1 

The transfer factor OL. for the k product of the 1 animal, in units 

of 1* f? , is also given by a similar relation: 

Bq.a" air 

\ i 

Cil 

3 

B 

I 

B 

where f_. denotes the carbon content of the anlaal product. The expression 

is based on the following assuaptions: 

(1) all feed Is produced ln situ, 

(11) intake of both

 ikC and stable carbon present as bicarbonate in 

drinking water is saall in comparison to the total Intake via all 

routes of ^ C and atable carbon, respectively, 

(c) Trltiua/1*^ Transfer Factor Calculations 

Results of illustrative transfer factor calculations for trltiua and

 l**C 

are listed in Table I. Data on the hydrogen and carbon content of various 

foods, on which the calculations are based, are listed In Table 4. For 

trltiua, the higheat transfer factors are observed- for green vegetables and 

fruit although use of realistic soil water concentrations Indicates that root 

vegetables are also of soae Importance. Transfer factors for allk and 

cereals are relatively small however. Conversely, for ^C , the tranafer 

factors are highest for cereals and milk products with pork and beef being of 

secondary Importance. The calculations Illustrate the importance of 

considering a range of individual food products when assessing ingestion ~ 

doses from these two nuclides. 

4. VALIDATION OF THE DYNAMIC MODEL 

Validation of the dynamic model can be achieved by: 

(1) comparing model predictions with experimentally measured data, 

and/or 

(11) comparing model predictions with predictions by other established 

models for a benchmark problem, and understanding the reasons for 

the observed differences. 

- 17 -
P.25. 

Of these, the comparison of aodel predictions with experimental data is of 

vital importance both ln Justifying the use of the model and ln suggesting 

improvements to the model. For this reason, a considerable amount of effort 

haa been expended ln this area and is summarised as follows: 

(1) The model predictions for the change with time of

 90Sr and l37Cs 

fallout levels in allk were coapared with the experiaental data 

(Wilson and Nair, 1981).. The comparison, which is summarised 

below, was aimed at testing the validity of the pasture-cow-milk 

foodchain for

 90Sr and 137Ca as Incorporated in the dynaalc aodel. 

(11) An experiaental study was commissioned in 1980 to obtain timedependent data on the uptake froa soil of a range of radionuclides 

into a range of crops, in order to test and improve this aspect of 

the aodel. This study is now nesting completion and .results will 

be presented elsewhere (Grogan, et al, 1984). Further studlea, 

aimed at measuring interception factors and field7 loss for 

edible/non-edible plant parts and for non-uniform herbage density 

distributions, are also currently under consideration, based on the 

results of sensitivity studies recently carried out by Nair 

(1983). 

The results of the fallout data analysis are presented in Section 4.1 

below. Also, saaple results for a nominal case study-are presented in 

Section 4.2 to Illustrate the type of-results that may be generated from use 

of the model. Only the dynaalc aodel has been considered, because it. is 

likely to supersede the equilibrium model In future assessments and because 

the equilibrium model is simple enough such that the normal' verification 

procedures will suffice. 

4.1 Fallout Data Analysis 

Deposition rates of

 90Sr and 137Cs from fallout ln the .UK have been ' 

monitored continuously since the 1950s (Cambray et al,. 1979)-while, ln a 

separate programme, the activity levels ln milk, bulk-averaged throughout the 

UK, have been recorded over the last 24 yesrs (ARC, 1978).- The data are 

plotted in Fig. 4. The large time fluctuation in the data, occurring as a 

result of the Nuclear Test Ban-Treaty, provides an excellent test of the 

ability of a dynamic model to predict activity levels ln milk. 

Inlltal parameter values for the dynamic model,, specific to the pasturecow-milk pathway, together with possible upper and lower bounds, were 

obtained from a literature search. The fallout deposition rate measurements 

were input to the model and calculated activity levels ln milk compared with 

- 18 -
I 

fl 

I 

J 

the quarterly measured values. A 'constrained least squares analysis' was 

then carried out to Improve the fit, each parameter being allowed to vary 

within ita range. Results of the initial and final fits are shown in Fig. 5, 

while the significance of the various food-chain pathways within the overall 

food-web Is illustrated In Pig. 6. Plant tissue contamination was the major 

source of

 90Sr in milk after 1964, and direct ingestion of soil by the cow 

was the major source cf

 137Cs in milk after 1973. This reflects the rapid 

fixation of caesium in the soil thereby reducing availability for root 

uptake, and the enhanced uptake of strontium Into plant tissue additional to 

normal root uptake, a mechanism termed 'plant-base' uptake. Full details are 

given by Wilson & Nair (1981). It is important to note, however, that the 

results are applicable to.'average' UK conditions and may, therefore, be 

Inappropriate for certain specific situations. The results indicate, 

however, that the measured fallout data in milk are adequately reproduced by 

the pa8ture-cow-mllk foodchain incorporated in the dynamic aodel• They also 

demonstrate clearly the power of the dynamic modelling technique ln 

identifying the critical exposure pathways for different nuclides at 

different time periods. 

4.2 Sample Calculations 

Sample calculations were made, using the dynamic model, fcr activity 

levels in green and root vegetables, grain, milk and beef following a unit 

y t * * 90o 106„ 129,13lT " 137„ - . _ v • -. 

-deposition of Sr, Ru, I and Cs occurring- instantaneously. _The 

calculations utilised a standard library of rate constant data described ln 

Appendix 4.. The deposition was assumed to take place 30 days before harvest 

for arable crops and at the start of the summer grazing for animals. 

Activity levels in the foods were calculated at times upto 10** days after 

deposition assuming discrete annual harvests for the arable crops and 

continuous production of milk and beef. A 100 day growing season was assumed 

for crops and a 145 day growing season for pasture. The cow diet was assumed 

to consist of"58 kgrns.d"1 wet weight of grass in the growing season and 

5 kgrns.d"1 hay/silage and 20 kgrns.d"1 straw in the fallow season. A direct 

soil intake was also assumed at all times consisting of 2Z of all other 

Intake-on a dry weight soil/dry weight feed basis. This is in addition to 

consumption of the smaller amounts of soil resuspended onto the feed. 

The results of the calculations are presented in Figure 7. The curves 

for the arable crops are eye guides licking the calculated discrete levels ln 

tne crops at the various harvecrs. Thus they do not imply continuous 

production of the crops all year around. On the other hand, the curves for 

- 19 -
P.27 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

t 

I 

I 

I 

I 

• 

•l 

II 

1 

ailk and beef genuinely assume continuous production although the effeets of 

radionuclide tranafer In the fallow season have not been considered in 

detail. The calculations do not account for decay during food storage or for 

any activity loss/concentration during food processing. The reduction ln the 

rate of decrease of

 137Cs activity with tlae is accounted for by the fact 

that the activity levels ln the foods are determined by the Inventory of 

fixed Cs in the soil ln the ploughed layer. This inventory'increases with 

time as the fixed Cs is assumed not to move into deeper soil zones. Thus the 

dominant processes for Cs uptake at longer times are resuspenslon of soil 

onto arable crops and direct Intake of soil by cows. This is borne out by 

the close correlation observed between changes in Cs levels in the soil and 

ln the foods. A converse example is

 90Sr. Here the levels in milk and beef 

follow, closely the levels in pasture thereby indicating the lack of" 

laportance of direct soil Intake by cows. The prlaary aode of uptake of Sr 

froa the soil is also seen to be root uptake rather than soil resuspenslon. 

106„ . 129,131,. . . - . - . " „ . 137. . 90-

Ru and I behave in a manner intermediate between Cs and Sr 

although the relatively short radioactive half-lives of

 106Ru and 131 I, in 

particular, impose severe constraints on the time-dependent behaviour of 

their respective concentrations in the various foods. 

5. THE CALCULATION OF INDIVIDUAL DOSE FROM INGESTION 

The calculation of activity levels in the various foods at the time of 

consumption is only the first step in the calculation of ingestion dose. For 

the case of continuous.releases, the quantity usually evaluated is the 

committed dose from one year's intake. For intake of a single nuclide in a 

single food,, this is given by: 

ftijk " Cij x di x DIJk» 

where: ft.. denotea the -committed dose to organ k from intake of nuclide J in 

- food i over one year (Sv a l ) , 

C. denotes the concentration of nuclide j in food 1 at 

consumption (Bq.kgm"1), 

d denotes-the dietary intake rate of food i (kgms.a"1), 

Jk 

D^ denotes the committed dose to organ k from unit intake of 

nuclide j. 

The total dose from one year's intake is then obtained by summing over 

all nuclides and foods, viz. 

- 20 -
Total coaaltted dose to organ k froa one year's Intake 

P.28 

I 

fl 

I 

fl 

I 

I 

I 

Z E C A D 3 k 

Foods i Nuclides j **ij i I 

-

 Z d £ C D J k 

. Value* for critical group adult dietary Intake rates, quoted by Harrison 

and Siaaonds (1980), are included in the standard FOODWEB data library as are 

the adult ingestion dose-intake factors for all relevant nuclides considered 

by the NECTAR code and quoted in ICRP30 (1979). Different values aay, 

however, be input by the user. 

For the case pf accidental releases, the committed dose tp organ k froa 

one day's intake of nuclide J ln food 1 is given by the equation: 

ft ijk " <?ij »

 d i x D Ik

» 

where H. .. is now in units of Sv.day and d. in units of kgms.day ; , all 

other quantities being as defined above. Summation over all nuclides and 

food* yields the committed dose from one day's Intake of all nuclides in all 

food*. This result is calculated by the FOODWEB module. The integrated dose 

froa intake upto a time T aay then be calculated as follows: 

(a) Crops": Let t . denote the aean storage time of the crop from 

harvest to. consumption. If- consumption occurs at a uniform rate" froa time 

zero, this implies a maximum storage time of 2 t ,. If radionuclide decay is 

saall over this, time period, the dbse to organ from nuclide j ln crop 1 from 

this harvest h is: . 

*ijk C. . x d. x 2 t , X ij _l_ si y 

H

 h - D *k 

H ijk " °I 

/•T-d.("t) C,h.. (t)dt, where T denotes 

O 1 IJK 

The. exact' solution .is: 

the time period over which .consumption occurs at a time varying rate d . For 

the case of a constant intake d of a.parent nuclide occurring over a time 

period 2t. ., this reduces-to: .."-'-_ 

"ijk "

 Cijk ^t si) di DI 

jk 

V si "Vsi 

- e 

The result quoted above is a special case when X_t « 1. 

- 21 -
P.29 

Since C.. will be different for different harvests, the dose from all 

harvests upto time T is given by: 

H Ijk • IH ljk» 

vhere the summation .Is carried out over all harvests upto the required tlae 

T. The total dose, H. , to organ k is then obtained by summing over all 

nuclides and foods so that: 

v - ? Idi Si J Di

3k

 J ci5'•'" 

(b) Animal Product*: A different procedure Is necessary for animal products 

a* these are assuaed to be produced continuously. In this case, the dose to 

orgaa k upto tlae T froa consumption of nuclide j in food 1 Is given by: 

H ijk - c^xd^D^ . 

vhere: c.. - Total number of disintegrations of nuclide j ln food 1 upto 

!• ~ time T -

- /Q Cti (t)dt (Bq.d.kga ), 

and all other symbols are as defined previously. The total dose, H, , is thus 

given by: 

•k " * d i J D I

3 k 'oT Cij < c >d t V 

6. THE CALCULATION OF INGESTION POPULATION DOSE 

The calculation of ingestion population dose uses, as a starting point, 

the calculated activity levels In the "various foods as consumed. The 

calculation also requires as input a dowuwind/cfosswlnd matrix of deposition 

rates (or. In the case of tritium, air concentrations and wet deposition 

rates and, in the case of ^C, air concentrations only). Also required is an 

agricultural products data base. For this reason, the calculatlonal methods 

and data are considered separately below. 

6.1 Methods 

The committed population dose to organ k for the consumption of one 

year's production of food 1 containing nuclide j and produced at location 1 

is given by: 

- 22 -
P.30 

I 

I 

I 

I 

I 

I 

I 

! 

I 

*ijkl ' Cijl

 x xil x Fi x D I • 

where: S.... denotes the required population dose ln units man-Sv.a , 

x.. denotes the total annual production of food 1 at location 1 

F denotes the fraction of this that is consumed by"the population at 

by: 

(kga.a-1), 

F denotes 

large, and 

ik C!.. and D^ denote the concentration at consumption of nuclide j ln 

food 1 produced at location 1 (Bq.kgm"1) and D:: the ingestion doseintake factor for organ k aa defined previously (Sv.Bq-1). 

For the case of continuous releasee, the concentration, C!.,, is given 

C — Sbl . — 

ijl ij Jl* 

where a denotes the static transfer factor and u.. denotes: 

(1) the standing air concentration for

 1(*C releaaes and for all tritium 

releases not involving the assessment of doses froa root 

vegetables, 

(11) the soil water concentration for the assessment of doses from 

tritium incorporated in root vegetables - this equals the wet 

deposition" rate divided by the rainfall rate., 

(ill) the total deposition rate f roar both dry and wet deposition for all 

other nuclides. 

Substitution of the above expression in the expression for ^l1t l and 

sunning over all locations 1, nuclides j and foods.! gives the total 

committed population dose to organ k from one year's intake: 

sk - i Fi jDxk au j x n -ji- _v_ ;- " "-•_.•_ 

For the case of accidental releases, the .concentration of nuclide j in 

food 1 is calculated at a specified location using .the dynamic model. The 

corresponding concentrations at other locations 1 are then obtained by 

scaling by the ratio of deposition rates: 

C* • ^ C 

U l «j 8 ** ijs. 

- 23 -
P.31 

where ta. and C* refer to the specified location. The committed dose to 

Js ijs 

organ k froa one year's Intake is then: 

This result Is calculated by the FOODWEB aodule. The Integrated 

population dose froa Intake upto a time T may then be calculated using . 

procedures analogous to those outlined in Section 5 for both crops and animal 

products-. 

6.2 Data 

.. Data needed for the ingestion population dose calculations consist of: 

(i) A matrix of deposition rates and/or air concentrations, to.., for 

each nuclide j at each downwind/crosswind location 1, 

(11) A countrywide annual average rainfall data library, 

(ill) A countrywide agricultural products distribution for each food 

product, specifying the annual production, x.., of food i at 

location 1, 

(iv) value* for the fraction, F., of the annual production of each food 

product 1 that is consumed by the population at large. 

Of these, the matrix of deposition rates/air-concentrations can.be input 

directly by the user into FOODWEB. Alternatively it can be output from the 

NECTAR-ATMOS module (which handles the atmospheric dispersion calculations) 

into a utility disc interface from which it can be read directly into 

FOODVEB. A countrywide annual average rainfall data library has also been 

constructed, based on a 5x5 km grid for annual average rainfall over the 

period 1941 - 1970. The data library is only needed for calculations, of the 

ingestion population dose from consumption of tritium in root vegetables. 

Items (ili) and (iv) required more effort to collate and are .described 

in turn below. r -••_.--.- -

6.2.1 Production of Agricultural Products Data Library 

The agricultural products data library.describes the tpa'tlal 

distribution of production, in England, Wales and Scotland, of ten-foodproducts which broadly cover the UK diet, namely: (i) milk, (ii) beef and 

veal, (ill) pork, bacon and ham, (lv) poultry meat, (v) eggs, (vl) mutton and 

lamb, (vil) root vegetables, (viii) green vegetables, (ix) fruit, (x) 

cereals. The library is based on the detailed 1972 land use and livestock 

census data in conjunction with annual food production data supplied to the 

author by MAFF (Thompson, 1979). The various parts of the library are 

considered below. 

- 24 -
I' ' 

(a) The Crop Productivity/Animal Product Yield Data 

Crop productivity data: Crop productivity data for the various English 

and Welsh counties were supplied for the 23 separate crops listed ln Table 5. 

The data indicated significant regional variations in productivity, which 

necessitated the use of detailed county crop productivity data rather than a 

UK average-value for a particular crop. However, the detailed county 

apecific data were not available for Scotland and average .yields, supplied by 

the Department of Agriculture and Fisheries in Scotland (Martin, 1979), were 

used in this ease. -

Animal product yield data: These data consist of the annual yield of 

allk, beef and veal, pork, bacon and haa:etc, per head of livestock 

calculated froa statistics published ln the Annual Reviev of Agriculture 

.(1979) and are listed in Table 6. 

(b) Census collection and initial processing 

The census dsta are collected by fan holding* on the basis of the area* 

of land on vhich" each crop ia grown and the nuaber* of various categories of 

livestock. About 200 questions are answered by faraera, the returns being 

confidential. However, summaries of the parish returns are available for 

general use and the parish data for the 1972 census were used. 

The county crop productivity data vere used to' convert the land use 

census data to annual crop yields in a parish for each of the 23 crops.- The 

data were then condensed to the broad categories of crops considered, namely, 

root vegetables, green vegetables, fruit and cereals. For the case of 

-livestock, the animal product yield data were used to convert numbers of " 

livestock to annual yields of milk, beef, pork, poultry, eggs and mutton on a 

parish-by-parish basis. 

(c) Preparation of grid data 

The parishes are lrregulsr in shape and aire so that a rational 

presentation of the information for areal processing Is difficult. A - : 

computer program -was therefore developed under contract to the University of 

Edinburgh, which-divides the parish data evenly over the 1 x 1 km squares of. 

the parish and reaggregates them on an arbitrary sized square grid. In order 

to divide the data In this way, the program accesses a data file of 

information on the" parish framework of England, Wales and Scotland based on 

the 1 km grid. The square grid information may be output by the program for 

any size squares Into which the 100 x IOC km squares of the National Grid may 

be evenly divided. 

- 25 -
For this particular case, a 5 x 5 km square grid system was chosen and 

the prograa wa* used to generate annual food production data for each of the 

ten products ln each grid, 

(d) Mapping of data 

The resulting agricultural data libraries for each product were aapped 

ualng a computer-based graph" plotting system developed by the University of 

Edinburgh and the maps are presented in Figures 8-17. Grouped values for 

each calculation are illustrated by separate-symbols representing the 5x5 ka 

squares of the National Grid. In interpreting them, it should be noted that 

the squares along the coast and on the English/Scottish border fall into a 

different category. These are 5x5 ka squares which aay only Include one of 

the 1 ka square* of land Inforaation,. the other* being aea or land on the 

other aide of the border, this has the effect of both increasing the 

apparent area of the land in question and indicating smaller amounts of 

agricultural activity than expected. 

...The agricultural data libraries were considered to be detailed enough to 

Justify their use In population dose calculations covering large area* of 

countryside. However, it is emphasized that the census relates to one day in 

the year, the 1st of June, and patterns of agricultural activity change 

throughout the year, especially those/concerning stock. Moreover, the. 

grouped-farm holdings do not conform exactly to the civil parish, the 

boundaries .of which have been used to determine the 1 ka square grid, while 

urban areas, open water and agricultural land have been weighted equally, 

when estimating agricultural activity. However, these detailed effects have 

little impact on population dose calculations and were therefore ignored. 

6.2.2 The Food Utilisation Data 

The food utilisation data base consists of the fraction of the annual 

production of each food consumed by the population. The data are derived 

below.' 

(a) Milk "•-.." 

"-.'. Data published in the Annual Review of Agriculture (1979) indicate that 

while the annual production for liquid consumption has declined slightly, the 

production for manufacture has increased by neatly 90Z between 1967 and. 1978 

auch that in 1978 only 50Z of the total annual milk production was consumed 

In unprocessed form. This leads to an overall utilisation factor of 57Z, 

accounting for mass compaction and losses incurred during manufacture. 

Separate factors for liquid and manufactured milk are 50Z and 7Z 

respectively. 

- 26 -
P.34 

I 

I 

B 

8 

I 

(b) Other animal products 

Utilisation factors of 100Z were aaaumed in the absence of any data. 

However, if exports are Ignored and only UK consumption is considered, these 

factors reduce totBeef and veal: 94Z; Pork, bacon and ham: 99Z; 

Poultrymeat: 100Z; Eggs: 97Z; Mutton and laab: 95Z. 

(c) Root vegetables 

Data for root vegetables were derived considering only potatoes. About 

47Z of the crop is sold raw in the UK, a further 10Z is processed and 

consumed in the UK while 0.82 is exported, these being annual average data 

for the years 1969-1972. Typically, 3.5 ton* of raw potatoes are required to 

produce 1 ton of processed potatoes owing to the reduction ln water content ; 

during food processing. .Thus, if activity per unit veight is unchanged 

during processing, the overall utilisation factor is: 

I 

«*•&* » 

reducing to 50Z if experts are Ignored and only UK consumption is 

considered. 

(d) Green vegetables 

No data were available for green vegetables. A utilisation faccor of 

94Z, in line with that derived below for fruit, was assumed. 

(e) Fruit 

Data for fruit were derived considering only orchard fruit. Exports of 

orchard fruit are insignificant and about 95Z of the harvest Is consumed in 

the country, the rest going to waste. The overall utilisation faccor was 

found co be 94Z accounting for the small fraction of the crop that is 

processed and for losses during processing. 

(f) Cereals -

Data supplied to the authors by.MAFF Indicate that between 1971 and 

1979, an average of.332 of the annual cereal crop was retained for human 

consumption, the rest being utilised as animal feed or seed. About 6Z of the 

crop was exported, leaving 27Z for consumption within the UK. The-extrsction 

rate of flour from wheat and of malt from barley is about 75Z. Thus, If all 

cereals are assumed to be processed, the overall factor is:-

33 x 0.75 - 25Z, 

reducing to 202 if only UK consumption Is considered. 

- 27 -
7. CONCLUSIONS 

In this report various methods have been described which are currently 

being used within CEGB to assess ingestion doses froa consumption of 

terrestrial foods following an atmospheric radioactive release. The 

essential steps ln such an assessment are: 

(1) the-calculation of nuclide concentration-levels in various foods 

corresponding to a known deposition from the plume or to a known 

air concentration, 

(11) the calculation of the individual dose arising from these. . 

concentration levels for an assumed diet, 

(ill) the calculation of the population dose from ingestion of foods 

produced in the affected areas. 

0f~these, the calculation of nuclide concentration levels in foodstuffs 

is the most complex and is achieved via the use of an appropriate foodchain 

aodel. Four such separate aodels are currently in use, namely: 

(1) a dynaalc (i.e. time-dependent) model encompassing a wide range of 

foodchain pathways and applicable to the assessment of dose* froa 

both continuous and discrete releases, 

(11) a siaple equilibrium model encompassing a limited number of 

foodchain pathways and applicable by definition only to the 

assessment of doses froa continuous releases, 

(Hi) two "special ease" aodels applicable to-the assessment of doses 

from continuous releases of tritium and

 ll*C in the chemical foras 

HTO and CO2, respectively." 

These are fully described and their advantages and disadvantages 

coapared and contrasted. Of these, the dynaalc aodel is likely to supersede 

the equilibrium model in future assessments. Thus results are presented of a 

validation of the dynamic model against experimentally measured data on

 90Sr 

and

 137Cs fallout levels in milk.; Results are also presented of sample 

calculations using the various models.V 

The calculation of individual doses from the derived nuclide food 

concentration levels is relatively simple. However, the calculation of the 

corresponding population doses requires a range of supporting data, the most 

important of which la a library describing the spatial distribution of 

production of a wide range of food products, the production of such a 

library is described and relevant maps are presented of agricultural product 

distributions in Great Brl:aln. 

- 28 -
P.36 

| 

I 

I 

I 

I 

I 

fl 

B 

I 

I 

I 

I 

i 

Finally, the philosophy behind the development of the aodels is 

••saarlsed aa are both on-going and proposed future supporting experiaental 

prograaaes. The aethods described in this report have been incorporated in 

the FOODWEB aodule of the CEGB'a NECTAR environmental code. 

REFERENCES 

1. _ Annual Review of Agriculture, 1979, Cmnd. 7436, HMSO. 

2. T A.R.C. Leteombe Laboratory, 1958-1978, Annual Reports pub. Agricultural 

Research Council and HMSO. 

3. Caabray, R.S., Fisher, E.M.R., Eakina, J.D.,; Pelrson, D.H., 1979, 

"Radioactive Fallout ln Air and Rain: Results to the. end of 1978", 

UKAEA Harwell and HMSO. 

4. CEC, 1979, "Methodology for Evaluating the Radiological Consequences of 

Radioactive Effluents Released ln Normal Operations", Report No. 

V/3865/79-EN to CEC by NRPB/CEA. 

5. Chamberlain, A.C., 1970, "Interception and Retention of Radioactive 

Aerosols by Vegetation", Atmos. Env* 4, 57-78. 

-6. Cliaatological Memorandum 103, 1976, "Averages and Frequency 

Distributions of Humidity for Great Britain and Northern Ireland 

1961-70", Meteorological Office and HMSO. 

7. Cough trey, P.J., Thorne, M.C , 1983, "Radionuclide Diatribution and 

Transport in Terrestrial and Aquatic Ecosystems - A Critical Review of 

Data", Volumes 1-3, ed. A.A. Balkema, Rotterdam. -

8. Elwood, J.W., 1971, "Ecological Aspects of Tritium Behaviour in the 

Environment", Nud. Safety, 12, 4, 326. 

9. Evans, A.G., 1969, "New Dose Estimates from Chronic Tritium Exposures", 

Health Physics, ^6_, 57. 

10. Grogan, H.A., Bell, J.N.B., Minsk!, M.J., Nair, S., 1984, "An 

Experimental Study of the Time Dependence of Uptake from Soil of

 137 C s, 

106Ru, ^C e and 99Tc Into Green Vegetables, Wheat and Potatoes", CEGB 

report TPRD/B/0416/N84, to be published. 

-11. Harrison, N.J., Simmonds, J.R., 1980, "Dosimetric-Quantities and Basic 

Data for the Evaluation of Generalised Derived Limits", NRPB reportNRPB-DL3. 

12. ICRP Publication 30, 1979, "Limits for Intakes of Radionuclides by 

Workers", Annals of the ICRP, Z_, 3-4, 3^, 1-4, 4y 3-4 and £, 1-6. 

13. IUR, 1982, "Report on a Workshop.on the Measurement of Soils to Plant 

Transfer Factors for Radionuclides", Part I (Report prepared by 

Association EURATOM-ITAL, P.O. Box 48, 6700 AA, Wagenlngen, Netherlands, 

cf Dr. M.J. Frissel). 

14. Martin, P.C, 1979, Private Communication. 

- 29 -
P.37 

15. McKone, T.E., Kastenberg, W.E., 1978, "Calculation of Radiological Dose 

due to Release of Trltiua Oxides froa Controlled Thermonuclear 

Reactors", Nucl. Tech. 40, 170. 

16. Nair, S., Hotson, J., Stacey, A., 1980, "POPFOOD - A Coaputer Code for 

Calculating Ingestion Collective Doses froa Continuous Ataospherie 

Releases", CEGB report RD/B/N4888. 

17. Nair, S-, 1982, "A User's Guide to the Foddweb Transfer Module NECTAR-

- FOODWEB", CEGB report RD/B/5195N82. 

18. Nair, S., 1983, "A Sensitivity Study of Ingestion Population Doae 

Following a Hypothetical Ataospherie Release froa a.Nuclear Power 

•--;'_-- Station", P?oc..CEC Seminar on The Transfer of Radioactive Materials in 

the Terrestrial Environment Subsequent, to an Accidental Release to 

Atmosphere, 2, 523, ll-15th April 1983, Dublin. 

19. Ng, T.C., Colsher, C.S.," Quinn, D.J., thoapson, S.E., 1977, "Transfer. -

. Coefficient* for the" Prediction of the .Dose to Man via the Forage-CowMilk Pathway-from Radionuclides Released to the Biosphere", Report UCRL-

• 51939. • . -. •" yy •• 

20. Mg, T.C , Colsher, C.S., Thoapson, S.E.,. 1982a, "Soil-to-Plant 

Concentration" Factors for Radiological Assessments", Report UCID-19463 

(NUREG/CR-2975). 

21. Ng, T.C, Colsher, C.S., Thompson, S.E.\ 1982b, "Tranafer Coefficient* 

for Assessing the 0o*e froa Radionuclides in Meat and Eggs", Report 

UCID-19464 (NUREC/CR-2976). '.'. = '.- . 

22. Scott.Russell, R., 1966, "Radioactivity'and Huaan Diet", ed.:Pergamon 

Press. ..'.-•:"-"• -

 :

_ ..•'"-.."--'' - ' y ' ' ".;.- -

. . • . . - - •--'-_"-..-.'• . • - - -

23. Siaaonds, J.R., Crick, Ji.J., 1982, "Transfer parameters for Use in 

Terrestrial Foodchain Models", URPBaemorandum NRPB-M63. 

24. Thoapson, J.F., 1979", Private Communication. 

25. Wilson, J.J.N., Nair, S., 1981, "A Computer Analysis of

 90Sr and l37Cs 

Fallout Levels in Milk in the U.K.", CEGB report RD/B/5104N81. 

- 30 -
TABLE I 

Listing of Transfer Factor*

 ,! i 

i 

ui 

Food 

Root Vegetables 

Creen Vegetables 

Fruit 

Cereals 

Liquid Milk -

Aversge Diet 

Liquid Milk -

"Crass only" diet 

Milk Products 

Beef 

Fork 

Poultirymest 

Eggs 

• i Mutton & Lamb 

i • 

B<1 kg-»/Bq 

3H 

9.9x10"''* 

150 

150 

1 86 

46 

62 

•' 31 

3* 

'

 l6 

24 

. i ,22 ' 

36 

a"3 air 

1-C 

630 

170 

390 

2500 

390 

390 

3000 

1400 

1700 

690 

880 

1400 

IMl7.6 ' 

5200 

3800, : 

5400 

3.6xl0'» 

9.3x1b1* ' 

> 1 

2.3x10s „, 

4400 

0.14 

0.025 • 

U9 

360 

• . i 

1331 

0 

6.6 

4.8 

S.lxlO*5 

1062 

2700 

i 1.7X10-1* 

3.0xlO-2 

0 

0 

0 

2.5x10-* 

Bq kg-l/Bq a"2 a"1 

••'Sr 

1100 

LOxlO" 

9000 

•'.'xlO* 

1.6x10^ 

3.1X101* 

8.2x10" 

1500 ; 

190 

160 

6.6x10" 

410 

'°Sr 

6.3X101* 

1.9x10s 

l.'7xl0V 

3.7x10s 

4.6x10'' 

5.6x10" 

$. 5x10

 s 

4300 

1800 

1500 

5.3xl05 

2400 

' v, ' 

. i 

MIC* 

6.2x10'' 

2.8x10'' 

7.0x10'' 

4.6x10? 

1.7x10s 

2.2x10

 s 

1.3x10* 

2.1x10s 

1.1x10s 

1.0x10s 

1.6x10'' 

1.4x10s 

1 

137C. 

1.1x10* 

3.0x10'' 

7.2xlO,» 

4.8xl05 

1.8x10s 

2.3x10s 

I.4xl06 

2.3x10s 

1.3x10s 

1.2x10s 

1.8x10'' 

1.6x10s 

*Units of Bq.kg'VBq.a'Vsoil water 
TABLE 2(a) 

Dally Livestock Feed Intske Averaged Over I Year 

P.39 

• 

Dairy cows ~ 

Beef Cattle 

Swine 

(fattening 

piga) 

Broilers 

- Laying Hens 

Sheep. 

Hay/Silage 

kg d"1 

0++ 

1 

• . - • 

- .' 

" 

0.3 

Crass 

kg d~l 

23+ . 

58*+ 

12 

• - - ' • ' 

. - .-• 

0.23 

Straw 

kg d~l 

8.3 * 

3.3 

-

•y - ' 

0.83 

Concentrates 

... k* d"1 

Ao** 

2 

1.4 

0.075 " 

0.110 

0.1 

Water 

Intake 

kg d_ 1 

75 

45 

7 

0.20 

0.34 

3.5 

Breathing 

Rate 

a

3

 dry 

130 

136* 

8.6 

-."-- • - . " 

-'"" -r ' : " • 

. 8.6 

Saae rate of breathing assuaed for beef, cattle ae for dairy cattle. 

**" Average diet. 

"•"•""Grass only" diet. 

TABLE 2(b) 

Listing of Crop Yield Data 

Food Product 

Root vegetables 

Green vegetables 

Fruit 

Cereals 

Crass 

Straw 

Hay 

Recoverable Yield ". 

kg fresh weight/a2 

2.36 

1.43 

7.27 

0.67 

2*97 -

2.58 

0.56 

""••" —:—~—n 

- Dry Matter Content 

0.25 . 

- 0.073 . -

0.16T 

0.88 

0.17 . 

0.27 

0.90 

- 32 -
P.40 

TABLE 2(c) 

Mean Storage Tiaes 

Food product 

Root Vegetables 

Green Vegetables • 

Fruit 

Cereals 

: Milk 

Milk Products 

Beef 

V Pork " 

Poultry -

Eggs 

Lamb/Mutton 

Best Estimate 

(days) 

90 

7 

7 

30 

1 

30 

14 . 

14 

14 -

3 

14 

- 33 -
TABLE 2(d) . 

Listing of Nucllde-Speclflc Data 

Listing of Translocation Factot* 

u* 

"

S""*s->s^ Nuclide 

Pood^^*"*^^ 

Product ^r-^s^ ^ 

Root vegetables 

Green vegetables 

Fruit, 

Cereals 

i 

9°Sr 

• 

0.01 

0.06 

0.08 

O.U 

l06Ru 

0.05 

0.05 

0.05 

0.05 

i 

129' 

i 

0.1 

0.1 

0.1 

0.1 

*"c. 

0.18 

0.14 

0*50 

0.32 

***i 

0.01 

0.02 

0.025 , 

0.03 

238,239^ 

1 

0.01 

0.01 

0.01 

0.01 

2*lAa 

- .. i ' ' 

0.01 

0.02 

0.025 

0.03 

2«Ca 

0.01 

0.02 

0.025 

0.03 

M li • . . i • 
TABLE 2(d) (Cont.) .',•.. 

' ' '. 

' . Listing pf Soll+Planti Concentration' Factor* 

(Units of Bq/kga fresh wt plant per Bq/kga vet wt soil) 

•v . 

u> 

^",'^^v >^ Nuclide . 

Food^'*^»v»v^ 

Product ^"^""^v^ 

Root vegetables 

Green vegetables 

Fruit 

Ceresls 

Hay 

Crass 

Strsw 

> * r 

0.090 

6.069 

0.039 

6.28 

6.87 . 

i l 

6.16 

• i • : I 

6.26 

l0*Ru 

9x10-'' 

^.5xlO- 3 

l.9xl6"3 

0.017 

' |:0..li- •';.' 

' 0.02 

0.033 

I 

y i 

6.0361 

0.030 

0.039 

6.060 

0.22 : 

0.041 

0.065 

» 7 C g 

i 

.•'•'• ' 1 

0.033 

4.5x10"3 

0.023 

0.054 

6.16', 

0.031 

6.649 

*«*Ce 

5iUW?h 

2.4xl6"3 

7.7xl6-'» 

2.6x16"3 

6.611 

2.6x16"3 

3.3x16"3 

i 

238,239^ 

1.8xl6"3 

I-.A'xiQ-> 

2.9xl6-'» 

2.4xl0- 3 

I.08xl0~3 

2.0xl0-|» 

3i3xl0*'» 

2

*

lAa 

I.8x10- 3 

2.4x10"3 

7.7x10-'' 

2.4xl0"3 

2.17x10-* 

4.1x10-'' 

6.5xio-'' 

2«Ca 

1 , 

l.8xl(T3 

2,4x10"3 

7.7x10-'' 

2.4xl0"3 

2.17xl0- 3 

4.1x10-'' 

^.SxlO"'' 

Ceresls assumed to be processed. 
TABLE.2(d) (Cont.) 

Listing of Anlmsl Dlet+Anlaal Product Concentration Factors 

i (Units of Bq/kga fresh wt animal product per Bq/day eaten) 

u> 

o* 

^^'^v^ ' Nuclide 

Food^s > > N v^ 

Product ^>>s*<Vs>^ 

Liquid Hllk 

Beef & veal 

Pork, bacon & ham 

Poultry 

Eggs 

Mutton & lamb 

" "—r—~" 

,*°Sr< 

l.4xlO"3 

3.0x10"'' 

2.6xl0"3 

0.042 

10 

1.4xl0 - 3 

1

 ' i—i— • 

106Ru 

6.1xl0^7 

l.oxlO- 3 

0.022 

0.39 

6.0xlO"3 

O.OU 

129, 

4

i 

9.9x10-* 

i' 

7^0xlO-3, 

0.060 

0.20 

4.0 

0.030 

l37 C . 

7.1x10"3 

0.02 

0.25 

4.4 

0.45 

0.12 

1 

"«Ce 

2.0x10"s 

i 

e.oxur* 

7.5x10- 3 

0.13 , 

5.0xlO"3 

3.6xMT3 

i 

238,239^ 

IO"7 

8.0xl0"7 

, 10"s 

2.0xl0"s 

3.0xlO- 5 

4.8x10-* 

2

*

lAa 

2xl0- 5 

1.6xl0~6 

2.0x10-5 

3.6x10-5 

5.0x10"3 

9.6xl0"6 

2A2Q, 

2.0x10-5 

1.6xl0~6 

2.0xl0"s 

3.6x10-5 

5.0x10"3 

9.6xl0"6 
u 

P.44 

I 

B 

1 

I 

TABLE 3 -

Definition of Syabols Used in the Calculation of Animal Product 

Tranafer Factors for Trltiua 

SyabOl 

f Hkl 

*_ 

H 

J L 

*HL 

Wl " 

Definition 

Hydrogen content by weight of kt n 

product of -1TM anlaal. 

Pally air intake of the 1t h animal. 

Absolute humidity. 

Dally conauaption of anlaal feed L* 

Hydrogen content by weight of anlaal 

- feed L. 

Aally water intake of 1 * anlaal. 

Units 

-a3 air inhaled.day"1 

kgas .aoisture.a~3 air 

-kga*feed L.day"1 _ 

kgm.water.day 

(These definitions are repeated in the glossary.) 

- 37 -
TABLE 4 

Hydrogen and Carbon Content of Food* 

P.45 

i 

Food Item 

Liquid Milk 

Milk Product* 

Beef 

Pork 

Chicken 

y _ - Egg* 

Mutton 

Boot Vegetables 

Green Vegetables 

Fruit 

Cereals 

Hay/Silage 

Grass 

Straw & Kale 

Concentrates 

.. Hydrogen content 

0.11 

6.075 

0.692 

0.16 

6.699 

6.10 

6.16 

6.11 

6.11 

6.11 _ 

6.664 

0.064 

0.10 

0.099 

0.066 

Carbon Content 

0.062 

6.48 

6.23 . 

0.27 :";.-'•' 

e ai 

e.i* 

6.23 

e.ie 

6.627 

6.663 

6.40 

0.33 

6.16 

0.20 

0.40 

*- H"** - o.ni (i -

 dJT vt ) x ( .*$» H ) 

kga.wet wt - - .•;---• wet wt kgm.dry wt 

- 38 -
i P.46 

I 

I 

1 

B 

I 

V 

I 

B 

1 

1 

TABLE 5 

Listing of Crops Considered for Inclusion ln Agricultural 

Products Data Library 

Crop 

Wheat 

Barley '•'--. 

•'Oata

7

./ 

Early potatoes 

Malncrop potatoes 

Brussel sprout* 

Spring cabbage 

Summer & Autuan cabbage 

Winter cabbage 

• rSavoya 

Suaaer <•'.Autuan cauliflower -

; Winter cauliflower - -

Broad beans •-"•: 

Runner beana 

*• - French bean* 

Pea* for. harvesting y 

Green, peaa ; 

Celery 

• • .. Lettuce, 

.Watercress 

-~ ----- Dessert-apples .. Cooking apples 

•~" "-'-• **ar* ;', 

Broad grouping 

Cereals 

Root vegetables 

"Green vegetable*. 

•.A_ Fruit 

TABLE 6 

Annual Production of Anlaal Products per Head of Livestock 

- Food

: Produc

t - """ -

• ' _~ " "~ ." ' -y- -'•'. -•'.-

-'- y mik # "..'_"• 

Beef and veal 

: Pork

, bacon and ham 

Mutton and .lamb 

.Eggs 

Poultry meat- "•-* 

Yield _. 

(Te/year/animal) - 4.77 

0.160 

0.126 . 

0.016 

0.014 

0.013 

Bone-out meat 

- 39 -
APPENDIX 1 

Mathematical Aspects of the Dynaalc Model 

Al.l Model for Crops 

The tranafer processes depicted ln the compartaental aodel for crop* 

•hown in Figure 2 are characterised by the following rate conatant*:-

(a) Translocation: X_ » Rate eonstant for translocation'. froa surface S to 

tissue Tl Atoas.*-1. kgrn"1** incorporated in tlssue\ 

\Atoas.kga-1* on the surface / 

(b) Field loss: X ..» Rate constant for field loss (*~l) 

• y- p • -- .-.'• -

f. » Fraction of the total field loss transferred to 

labile surface soil LSS (All- activity aasuaed 

pessialstlcaily to be Instantly labila.) 

f. - Fraction of the total field .loss' transferred to plant 

. baee PB (Note: * x + £j < 1.) 

(e). Root uptake: X , - Rate eonstant for root uptake froa ploughed layer le. 

" - '_" I 0-15 (

Atoms *_ B~K kga-1.- fresh weight tissue \ 

Atoas. kga"1. wet .weight soil in 0-15 cas/ 

X , • As for X , but for root uptake froa the 15*30 ca. 

r2 rl. . r : -

 r

 -

soil zone. 

(d) Plant base: XpR • Rate constant for uptake froa plant base to tissue 

(

Atoas. s"1. kga"1* tlasueX 

Atoas. kga"}. plant base / 

- V -Rate constant for.transfer-from plant base to labile 

- surface.soil ~ *" 

(

Atoms, B*^1. kgm**1. wet weight soil ln 0-15 cms A 

Atoms, kgm"1. plant base ..-/"'.

 : 

Ce) Soil: Xp • Rate constant for fixation (s_ 1 ). Same value for both 

surface and deep soil* 

X - Rate eonstant for movement down soil (s- 1 ). 

- 40 -

I 
V 

Of these, \_, X__, X „ are dependent on the eleaent of which the nuclide la an 

isotope and on the crop, while X . and X are also dependent on the soil type. 

X_ and X are dependent only on the eleaent of which the nuclide 1* an Isotope 

•nd on the soil type. 

I 

B 

i 

The .fraction of the depositing.activity Intercepted, by foliage is given by. 

(Chamberlain, 1970): -. 

- , i.. e - ; ^v- . ..;-.•;•.. • 

where W is the foliar wet"weight per unit area, g is the dry aatter content by 

weight and ills a constant, the fractions depositing on plant base and soil: 

thu* ara: • -

U • 

;-ugW 

aad (l-f3)e -ww 

where f. 1* the fraction of activity not depositing on foliage that "deposits on ' 

th* plant base." For the purpose* of. the" model, "the plant base 1* treated 

identically to the labile surface aoil with'the saae density p but with an 

effective depth 1 . very auch .saaller than the depth I (" 15 cas) of the 

P b . _••'•" ' vv --" P-' 

ploughed layer. 

If S., T., (PB)., etc. denote the number of atoas per.unit weight of 

nuclide. 1 In each coapartaent, and S. , T. ,- (PB). etc. denote the nuaber of atoas 

of the parent nuclide k in the decay chain ln the saae- coapartaent, the system 

of equations is given by: — -~ ••-_ y : - --

'%r'm -(^Ri+ V+ S^h+if*. S*. sk jft'. ^w?)^;

 :y:

 / 

d(PB) 

dt »••( . *V

 SU t^ <

P B>i+l S FH>B^P B>k 

;«te)v^(pi-y%;y: 

d(Lss) / .-.".'- w v :;;:_ -

-jt-^7-'-?\hi'*. hi + > + ^ T

 X rii) (LSS) 1 . +

 |; S FV* N«c <WS>k 

+

 Ss i <PB> ..(Sf).....^]-. 

- 41 -
P.49. 

d(FSS) _ 

S T 1" " *Ri

 (PSS>1 + I SFki S k <FSS>k + *Fi(lW>l' 

k 

d(LDS) 

dt 

d(FDS) 

1 " " (Nil + > + *Pi + IS" Xr2i)<tDS>i * [S P ki \ k <"*>* + X Si<LSS) i' 

- X ^ (FDS)V 4 X SF,^ X,^ (FDS)k + Xp i (LDS)1. 

SF.( denotes splitting fraction for decay of nuclide k to nuclide 1, the 

tion k is over all nuclides it that are direct parents of 

dt: 

Here: X_. denote* total disintegration conatant for nuclide k (s _ 1 ) , 

denotes sp 

summation 

. .nuclide ij 

UL denote* the deposition rate of nuclide-i (Atoms, mi"2, s"1) 

p denote* the density of wet weight aoil (kga.a-3), 

A . denote* the effective depth of the plant base (a), 

Pb'- " - " . 

1 ' denote* the depth of the ploughed layer (a) , 

P' • • . : 

while.the various coapartaent Inventories are in the following unit*: 

S -- Atoas.kgm.-1. fresh weight in the edible part of the plant-arising only 

froa surface contamination,- y A - _ - y 

T -" Atoms .kgm-1. fresh weight in the edible part of the plant arising "only 

- from tissue contaalnation, 

PB - Atoaa.kgm"1. fresh weight in the plant, base, 

LSS - Atoms.kgar1. wet weight soil in a labile form in the 0-15 cms. slab, V 

LDS - Atoms .kgm"1. wet weight soil in a labile fora in the 15-30 cas. slab, 

FSS - Atoas.kgm"1. Wet weight soil in a fixed fora in the 0-15 ems. slab, 

FDS - Atoms .kgm"1. wet weight soil in a fixed fora in the 15-30 cas. slab. 

In an exact mathematical sense, the equations' are "only valid if the foliar 

density, W, of growing foliage is brought to the left hand_slde and the — 

equationa are re-written for the functions: a(t).-> W(t)S~(t), B(t) - W(t)T(t), 

y(t) - W(t)PB(t), ...etc. However, foliar growth is taken into account by 

diyiding the growing seaaon into aeveral time steps and varying W froa one tine 

step to the next, keeping it-constant within a given.time step. This procedure 

w i H only be necessary, however, in situations of prolonged deposition (eg. 

fallout) and is unlikely to be necessary for accident studies, when the time 

over which deposition occurs is ususlly small in comparison to the length of the 

growing season. 

The above set of equations is solved numerically upto the required time T 

using special techniques suited to the solution of stiff sparse matrix systeas. 
P.50 

The final values froa one Integration atep aay be uaed aa the initial values for 

the next atep* Deposition rates can be switched on and off while the change of 

seaaon froa a growing aeaaon to a fallow season is simulated by zeroing the 

surface (S), tlaaue (T), and plant baae (PB) coapartaent* before proceeding onto 

the next Integration atep. The activity level'of nuclide i in the crop at 

harvest Is calculated via the formula: _ 

A

o " Nt\h:*

 T i * l<ws>i + <pss>i ^ 1 

for green vegetables, fruit and cereals, and via the foraula: 

K

o~ \.[v + 1 ctss)i *<F?

s)i * r^ I 

for root vegetables. Here g denotes the fractional "dry soil content of the 

-•• *- - - t ••••-. ' - . - ' -

crop and g th'e dry aatter content of the soil. Radioactive decay froa harvest 

ft - - _---.--/-_ • 

to conauaption and activity loss/concentration dating food, processing 1* taken 

Into account to give the final activity level of nuclide i in the food: 

A

i

>

k7P^*>» -. -'_v.----"- ";r - ; 

where k. is the processing factor, t theaean-storage.tlae and F(t ) Is given 

generally by: 

"**•«' - A * 

F(t > - e " 9 + I %l ("t ) » and 

decay routes" R . 

^ A * VaW 

» :fr, r+1 is -the splitting 

, fraction "~for decay ofI1J

 (X_ -"X-)" nuclide r to nuclide, r+i ) ; 

P • 1 if r > J-2 

- ^vi. < w«< *•«•* q-r+1 

* The expression for F(t9) is the general analytical solution to the equationa 

for radioactive decay in a decay chain. 

- 43 -
P.51 

l i 

I 

I 

I 

I 

A1.2 Model for Anlaal Products 

The aodel for anlaal products Is depicted ln Figure 3. Anlaal intake of 

grass, hay/silsge, straw and soil are considered by the aodel. Level* in grass 

and atraw are calculated using a separate aodel for each which 1* identical to 

the aodel for crop* describedvabove. No storage 1* •••uaed for .grass but thi* 

is taken into account for straw. The levels in the soil Ingested directly •reassumed to be given by the sua of the labile and1 fixed surface soil coapartaent 

Inventories aa obtained froa the aodel for graaa while the level* ln hay/silsge, 

A., are also calculated froa the gras* aodel compartment inventories via the 

formula: 

i'yyy'-

iUyy 

ry 

f:;^-v 

i 

i 

Here S.r T., etc. denote atoa inventories la the various coapartaent* of the 

aodel for gra** while t . , g and g. denote the aaaa storage tlae for hay/sllage 

an g T» . ..-. : 

•nd the dty aatter content of grass and hay/sllage respectively. All other 

•yabol* were defined in Section Al«l. In particular k. aay be used to account 

for any activity loss/concentration in the hay/sllage froa processes other than 

radioactive decay (this facility is also available for straw). 

. The .next atep "in the calculation consists of computing the dally -activity 

intake by the anlaal. This is achieved firstly by computing average-nuclide 

.concentration levels over.the tlae step for grass, hay/silsge, atraw and soil 

respectively. If all feed is assuaed to be produced and consuaed in situ, the . 

dally Intake, I., of nuclide i, averaged over the time atep, is given by: 

^ " J g < Ag > + Jh. *h > + Js < 4 > + Jso < * £ >• ••' 

.where the J's and < A >*s refer to dietary intake and average activity levels 

per unit weight and subscripts g, tt» a and 'SO' refer to grass, hay/silage, -

straw and soil respectively. The eoneentration level, N.,~of nuclide 1 per unit 

-weight of the anlaal product is then given by: 

dN. __ 

irm-<hi+ W N i

+

 I-

 SPki ^ V * *i x i- • 

•'• '• k . . . •-.•- -

where: X^. - Rate constant for removal of nuclide 1 via metabolic processes 

(X„ Is the ssme for all nuclides of a given element), 

- 44 -
P.52 

I 

I 

Y, " Fractional transfer of nuclide 1 to unit weight of anlaal product 

(Y la tbe saae for all nuclides of a given eleaent) 

X_., SF. ., X_. and I are as defined previously. 

This stiff, sparse system of equations is also solved "numericaUy over the sa 

tiae-step aa war assuaed for grass. The final nuclide concentrationr N., in the 

•niaal product is then calculated via the. formula: 

where NT is the solution obtained from the system of diff erentlal" equations and" 

o .. _ ' i . . ---._--_••_-"-"- • 

k. and F(t) account for activity. Idea/concentration during food: processing and 

radioactive decay during "the tlae delay between the production of the aaiaal 

product and .its consumption. 

It is emphasized that the solutions for anlaal product* are approximate ,~ 

since the"anlaal Intake per day is calculated using constant: values for levels 

la grass, hay/sllage, straw and soil thst have been averaged over the tiae-step. 

This was done In order to keep coaputer" core space and execution tlae- -

requlreaenta.within.manageable bounds. In reality the levels in feed and soil 

will vary over the time step so that the accuracy of the calculations: will .. 

Increase with a decreasing time.step, particularly for short-lived radio- -

"nuclides. 

- 45 -
\ 

APPENDIX 2 

Derivation of Trltiua Transfer Pactora for Anlaal Products 

(Constant Humidity) 

-'- The trltiua concentration In the k product of the 1 animal, C- , is. 

related to the daily animal Intake of activity, I, by the relation: 

C kl" P k l X » (A2.1) 

where C . and 1 are in units of Bq.kga and Bq.day reapectlvely, and A , 

1* a constant. The dally anlaal intake of trltiua, I, i* given br: 

I V Inhalation + Ingestion + Skin Absorption 

. • B. X + K J T

 C T ^ + Bi x * (Intake via skin absorption aaauaed 

' * y T L"- -' «q«*l to Intake via inhalation) 

•"^yLi^y A <«•« 

feed L 

where B," and JT "denote the breathing rate and daily feed intake" by the anlaal. 

3 - - - 1 **r -. - i •--••- - - • " ••:.••-.. • - 3 - -

(a air.d and kga d ), -a.* . denotes the air concentration (Bq.a air), Cdenotes the activity concentration In anlaal feed L in units of Bq.kga . 

If the feed has the same specific activity of trltiua as air, and is assumed 

to be produced at the same location aa the animal, then: 

VT-"onTTHx air'-:. (A2.3) 

where f-_- and -11 denote -the hydrogen content by weight of feed L and the 

H L - -- • '-"-'"••. . .. --•_-•--._' -

abaolute humidity (gms.moisture.m air) respectively. 

The intermediate tranafer factor Bj. haa units of ^* _i» This-must 

Bq.day. 

equal the ratio'of the hydrogen content of the focd, fn^.. to the dally 

hydrogen intake it trltiua and hydrogen are assumed to be metabolised 

similarly. Thus: 

- 46 -
P.54 

P 

Pl 

P 

P 

P 

I 

I 

I I 

I 

I 

I 

I 

I 

I 

I 

1 

I 

I 

i 

i 

i 

i 

1 

fHkl *kgB H **" **" food k* 

Pkl " Hydrogen Intake ln water + Hydrogen intake via inhalation & 

akin absorption + Hydrogen Intake ln feed (kga.day ) 

fHkl 

I 

I " 0.111 W + 2 x B. x 0.111 xB+. t (JT f S 

A X _ Is His 

I* 

I ' ' •'

 fHki r ' • ': 

" 0.111 (Wx"+ 2 BL H) + Z (JL f^ * (A2*4) 

I y '"' -' y ••' 

Substitution of equations (A2.2), (A2.3) and (A2.4) into equation. (A2.1) and 

I division by x . gives the required transfer factor: 

• :•-• .-,.'-. ip^l_^,^_m"y: ;-._._•; 

•: _ - kl Bq.m air -*air . 

" 0.1U (Wr + 2 BXH) + X (JL f,^) * (A2.5) 

• — • -

This approach assumes that livestock absorb as auch trltiua via their skin as: 

they inhale and that, all livestock feed, is produced in situ* All anlaal 

drinking "water is also assumed to be uncontaalnated. This last assuaption '•--

-nay not be valid depending on specific circumstances eg. do the aniaals 

obtain their water froe a stream or from trough water? If the latter, is the 

trough water obtained froa. a local or a distant reservoir? In any event, -

formula A2.5 may easily be modified to account for animal Intake of . 

contaminated water. 

- 47 -
P.55 

APPENDIX 3 

Derivation of Trltiua Transfer Fsctors for Anlaal Products 

(Variable Humidity) 

Froa equation"(A2.5) the. tranafer factor a., at a conatant absolute 

humidity level H is given by: 

.•"T- 2 fHki

 Bl» b

 - 33i t J--<JL

 fRL>» c.'-'°-m

 \ +*f<*t «*>•

 d m

 °-221 B r 

(A3.1) 

Thus: 

h y bd 

rm ' * ''" a. h • .e* c .. 

°kl W ••" ctdH H(e*dH) " c+dH *H " e+dH' 

(A3.2) 

..----_ c+dH.^y H y . . ...--"" 

Substituting Into the general expression for <o> (see Section 3.3): y -

n-* T_ - F ... Vl (ar^) (V 

«*-I F - *., v «s+dH^, . ay , 

-> I (H^^)[(f-!)ln(^5i

ii>+Jln(-f^-)]. (A3.3) 

- -r-1^ r+1 r - - ;. _-- -r_ r 

-Substitution of expressions in (A3.1) for a, b, c , d gives the fina l result: 

y "•",••;:•. 'md J(J L f^ )

 : n-i F^-F ^ V I ' 

.

 <0 >

 = Wil l [o.lll W, + S (J •£•"•)}• \ <H - - H * ** <^H~> +.-. 

1 L L HL

 J r-l r+1 r . r 

fHklV ^ Pr-P

r+1 '^'^^tt^i, ' 

lo.lll Wx + E (J L f^) * J x <H m - Hr>

 l n

 <0.111 W1+£(JL fHL)40.222 ^ Xi_ * 

L * 

(A3.4) 

- 48 -
APPENDIX 4 

P.56 

I 

B 

B 

I 

I 

fl 

I 

The Calculation of Dynaalc Model Rate Constants froa 

Equilibrium Tranafer Data 

The equilibrium tranafer data consist of: (1) surface to tissue 

translocation factors," (11) root, uptake factors, »ad (Hi ) diet. to anlaal 

product transfer factors. Using" the notation of Appendix 1, the relevant 

rate constants are X_ for translocation, X aad X .for root uptake, and K. 

for transfer froa diet to animal product. In addition, Y denotes the 

fractional transfer to 1 kgm of the animal product* 

Methods for calculating the rate constants froa the equilibrium data are 

described below and the values incorporated in the NECTAR-FOODWEB dynaalc 

model data library are .alao listed. It Is emphaalsed, however, that the 

calculated values can.only, be approximate since they have not been tested 

•gainst tiae-dependent data, which are not available ln aost cases. Such a 

.test is earrently in progress for root uptake of a aelected set of nnclldes 

into, a selected set of crops. Results will be reported by Grogan et al 

(1984) and are likely to result In revised X. . values fcr a few nuclides and 

crops. 

A4.1 Translocation - = 

(•). Calculation-of.XI froa Translocation factor f^-

Input SURFACE 

(S) 

TISSUE 

i 

The relevant part of the dynamic model, for crops is reproduced above. X 

""•'-- . "".'-'- .."-'.-'- --"..-.. P 

denotes the rate constant for field loss from foliage while the additional 

rate constant. X denotea continuous harvesting (or cropping). At 

- - " P '. • • - . 

equilibrium? 

XcT - Xj.S, 

- 49 -

II 
P.57 

so that: 

T \ 

Z

m

TTe 

But the translocation factor, f_, is defined such that: 

ff -I T T 

: C 

?*"•'• *t" X e - V 

I If the aean length of the growing season is assuaed to be 145 days, then: 

% 1 J-1 o ,«-8 -1 X *. •rje' d • 8x10 a . 

Thus: 

Kp - 8x10"* f^ s"1. 

-(b) Data ' 

Values for f_ (and hence \_) are listed in Table A4.1 for the range of 

eleaents and crops covered by the"FOODWEB data library. The-available data 

are very sparse; thus the following ad hoc assuaptions were aade in eoapiling 

the data base: 

(1) If data for a given element ln only one crop were available, this 

waa assuaed to apply to all-crops, 

(11) 

(iii) 

fvvalues-for Rb and Y were assuaed to be the same aa for- Sr, for 

T . " _ •-----::•-•- -

all rare earths as for Ce, for Np as for Pu and for Cm, Cf, BH, Es 

as for Aa, 

a default value for f_ of 2x10 

T 

-3 

was assumed, where appropriate. 

Subject to the above assumptions, the values quoted for f_, were obtained 

from Coughtrey and Thome (1983), Nair et al (1980) and Simmonds and Crick 

(1982). 

A4.2 Root Uptake by Crops 

For crops, all uptake la assumed to occur from the ploughed layer, i.e. 

no uptake from deeper soil zones. Thus, by assumption, 

- 50 -
P.58 

x

 t, - o 

r2 

I 

ln all cases. Methods and data for calculating X . are specified below. 

(a) Calculation of X . froa root uptake factor C, SP 

B 

B 

B 

I 

1 

I 

Input 

- s, 

TISSUE 

(T) 

* -

• * X c <•**>"• 

X f ^q*

B -»'kga »T> 

r l Bq.kga'h^S 

LABILE 

SURFACE 

son. 

(LSS) 

• 

-1'-• : 

V a"1) 

-

FIXED 

SURFACE 

son. 

(FSS) 

. 

V

s

 i 

I 

The relevant part of the dynaalc aodel for crop, is reproduced above. - X . 

denotes the rate-constant for continous harvesting, X_ for.soil fixation (if 

any) and X for movement down the aoil-column. At equilibrium: 

X C T - xtl (LSS), :- . y y . 

so that: ". .- - . 

T 

.LSS 

But the root uptake factor, C__, is defined such thst: 

C„,. - SP LSS+FSS » 

- 51 -
P.59 

where C__ is in units Bq.kgm fresh weight plant per Bq.kgm freah weight 

•oil. 

If there 1* no fixation aechanlsa (X-O), then: 

Thus: 

or 

FSS • 

C

S P -

C

SP 

X

r i " 

0 and: 

T -

LSS* 

. - 1 

m

T". 

c . 

c SP 

Use of the above expression ln situations where there la fixation (i.e. X_ 

and FSS * 0) will lead to pessimistic valuea for X_.. Thus, in-all cases, -

! X r l< Xc CSP " ^ C S P »'K 

using the value for X derived ln Section A6.1. 

(b): Data- ' f . £ 

Value's for C__ and X . are-listed in Table A4.2 fpr the "range of 

eleaents and crops covered by the.FOODWEB data library. The available data 

are not as sparse aa was the ease for the translocation factors; however, the 

following assumptions had to be aade: 

(1) if data for a given eleaent in only one crop were available, this 

was assumed to apply to all crops, 

(11) C values for Gd, Tb and Dy were assumed to be the saae as for Eu 

and for Ca, Cf, Bk and Es as for Aa. _ -

Subject to the above, the values quoted for C_ were obtained from 

Coughtrey and Thome (1983), Nair et al (1980), CEC (1979) and Ng et air 

(1982a), corrected for plant and soil wet weights*. 

*Slnce the production of the above data, a new set of computerised listings 

of Cep have been produce j by the International Union of Radioecologists (IUR, 

1982), which may be used to update some of the key values for C_ . 

- 52 -
* I 

P.60 

I 

B 

I 

A4.3 Root Uptake into Fruit 

It ia assumed that the rate of uptake per unit labile soil eoneentration 

Into fruit (apple and peara) froa the top 15 ca layer is no different than 

froa deeper soil zones, 

lie. Xrl - Xr2 - Xf, say 

Methods and data for evaluating X are specified below. 

(a) Calculation of X froa root uptake factor C — 

(Bq.a" 'kga" »T V 

\ Bq.kga"1.LDS / r 

Input 

TISSUE 

(T) *.<*"*> 

J/Bq.«"1.kga"1.A 

\ Bq.kga .LSS / 

LABILE 

SURFACE 

SOIL 

(LSS) 

V""1) 

V

8

"

1

* 

IL LABILE 

DEEP 

SOIL 

(LDS) 

^(a"1) 

FIXED 

SURFACE 

SOIL 

(FSS) 

FIXED 

DEEP 

SOIL 

(FDS) 

*This does not aean that ehe uptake from the first 15 cms equals the uptake 

from deeper soil zones. In general, the former will exceed the latter owing 

to the time taken for radioactivity to percolate to the deeper soil zones. 

- 53 -
P.61 

y 

The relevant part of the dynaalc aodel 1* reproduced above, all rate 

constants being aa defined ln Section A4.2. At equlllbrlua: 

WX 

X_ (LSS) - CXS + Xy + ~ ) (LDS) and 

..-;" ---'.'...-

 p p 

X^ T - X_ (LSS+LDS), 

where W, p and I denote the kgm.fruit.m , the wet weight soil density 

(kga.a" ) and the depth of the surface soil1 tone (6.15a) respectively. 

Substitution of one equation into the other yields the result: 

I ^CV^1 + xs + xp + ^x r j * 

But the root uptake factor, C__, is given by: 

SP LSS+FSS 

If there is no fixation (X_ - FSS - 0), then: 

_T_ 

*SP " LSS C M - . M , 

while use of this relation for the case involving fixation will lead to 

pessimistic values for X . Thus: 

X

c V X S

+ X F+

pT Xr/ 

.Cr _- -iSP 

This yields a quadratic equation for X : 

,"•••• V- + fcs• 2v 'V- \ CSF1\ - V \ SP < w • ° 

-54 -
The positive solution is: 

P.62 

I 

I 

B 

I 

4 

For cases involving fixation, use of this equation results in 

pessiaistic values.for X while, for cases involving no fixation (X_-0), the 

aolution simplifies to: 

i K.^:^^yy^y> Xj. X. C« 2 W I T W "S.c "SP * 

For all elements except Cs we have (Wilson and Nair, 1981): 

Xy - 6, Xg - 2.315 x lo"1 0 a"1, 

while, for Cs: 

Xy - 2.431 x IO*8 s"1, Xg - 4.12X10"9 *- 1 

Resulting plots of X versus Ce_ are compared with a similar plot for 

crop* in Figure -A4.1. A somewhat longer mean growing season is assuaed for" 

fruit (X - 4.4 x io"8 s"1 - 1.4a"1). 

(b) Data -V 

Values for X__ and X are listed in Table A4.3 for the same elements and 

" . ~ -"" _ - - . _

s^ - r _ 

subject to the same assuaptions "as made in Section A4.2 for data listed ln 

Table A4.2. 

A4.4 Uptake into Animal Products 

The relevant parameters to be evaluated are \, and Y. Somewhat 

different aethods were applied to evaluate these for. the varioua animal 

products, which are considered in turn below. 

(a) Milk 

Input I 

ANIMAL 

PRODUCT 

(N) 

xf x! 

St *R 
I 

The relevant part of the dynamic model for animal products is reproduced 

above. The radionuclide disintegration conatant is denoted by X_. At 

equilibrium: 

( *M + *R)H " ^ » -

so that: 

1

 VS ' • • • 

Bat the diet to anlaal product transfer factor, f , is given by: 

f A I* -

* » *&- • 

If subscripts 1 snd 2 refer to two isotopes of the saae eleaent with value* 

of £. substantially different when aeaaured under identical conditions: 

•• V - •.~t7y~i7<.:''.y 'ttf^Tr I T!T " TT J »

 <Ti& T 2denot e

 JjJJ^ 

t

A2~hltia ln2 /f A2

 f A l \ ,_ 

;

fAl•: fA2yy'i fAl " fA2 \ h " Tl / ' ' 

., v '*1£ A2 n . \ fAl

 fA2 to2 

and r--3T—HT"

 (X

C R2 ~ Ntl^ " ~f =~f 

A1 -

 £A2 ^ m fAl £A2 

For milk products-,"the same >y applies for a given element. However, 

all activity is pessimistically assumed to be retained In the dry matter 

content (13Z by.weight) So that:."", ' 

_ ^H k 

Tmilk. 0.13 ' 

r 'prod..' 

- 56 -
P.64 

I 

I 

fl 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

Values for various radionuclide tranafer factors to allk were obtained 

froa Ng et al (1977). These are listed in Table A4.4, while corresponding 

values for stable eleaent tranafer factors and for y and X, are listed ln 

Table A4.5. 

(b) Meat and Eggs -„''.-••'"'.""-

Meat is divided into beef, pork, poultry snd mutton. Eggs.are also 

considered ln this section. The diet to anlaal product transfer factor-for a 

radionuclide is given by: 

which siapllfles to: 

•%'-.

 ; y'^y]/-y-y-:

y 

fA 

for a stable nuclide. 

The approach adopted for the fission products in meat was aa follow*: 

(1) obtain a set of eleaent tranafer factors f. for each anlaal 

product, froa" the literature, 

(ii) obtain a set of valuea for \. froa the Hterature using the 

formula: 

-8 -1 —1 ' 

Xj. •Metabolic rate constant + 3.17- x 10 s (or 1 year ) , 

where the anlaal is assuaed to have a mean life of ~ I year, 

(iii) calculate y via the formula: y » f X -

For the case of the actlnides,"values of f aad \ . were provided by 

Science Applications Inc. (SAI) under contract to CEGB, and their report is 

presented in Appendix 5. ~ 

For the case of eggs, "a value for L of 1 day (1.16x10 s ) was 

assumed, independent of nuclide, based on" the assumption that the egg 

production rate is approxiaately one per day on average* In this case: 

*-v 

*The data are not detailed enough to perait differences ln transfer of two 

stable isotopes to be noted, so the terms "stsble nuclide" and "element" are 

used interchangeably. 

- 57 -
P.65 

1 

I Values of f. are Hated in Table A4.6 for the various meats and for tba A 

edible part of the egg. The primary literature sources were: 

(1) Ng et al (1982b), 

(11) Nair et al (1980), 

(iii) Siaaonds and Crick (1982), 

(iv). Appendix 5 and the references quoted therein. 

Where data for eleaents were not available, data for radionuclides were . 

used to infer the eleaent values, using the foraulae given at the top of subsection (b). In this case, the nuclide of Interest is indicated in Table 

A4.6." Farther, in aany .caaes, data were available only for-one eleaent in . 

one seat* In thia caae, the-data were extrapolated to the other aeats via 

tha foraula: _ " ••-'. ' 

. • Meat yield for-anlaal 1 _ 

rA2 "Meat yield for anlaal 2-Al» 

where £.. aad £ „ denote the priaary and extrapolated transfer factors, 

respectively. The formula assumes that the fractional transfer per unit 

daily Intake 1* the saae for. all-aeats, which is broadly borne out by the 

case* where separate data exist "for" different meats. 

Valuea for X^. are listed in Table A4.7* The available data are too 

•parse to enable separate \y values"to be derived for:each meat.. The data 

listed In Tables A4.6 and A4.7 were used to calculate values of y via the 

foraula: 

• *- w - ;;; '•-• 

These are listed in Table"A4.8. 

- 58 -
IWil M . 

fit Thralobtto turn 

dan * 

*UI 

o.l:| 

y\ 

X.M 

S.U1 

aW 

rx 

•w 

«r 

0.1 

fcdOT5 

2*10*J 

fcHT5 

2*I0*J 

JuIO"1 

0 

0X1 

0X6 

(US 

0.U 

(.-») 

4 

8A- » 

1.0,-10 

" 

' 

• 

0 

• A - » 

4.8, -8 

'4.4,-9 

8.8, -9 

Dmmrt 

IrW 

|t» 

,*rl*l 

H> 

»(>. 

*l»l 

J ' l 

»(>l 

f

T 

0X1 

0M 

0X8 

0,11 

0.01 

0M 

0M 

0.11 

0X1 

aot 

0.0V 

O.OC* 

0.1 

0.1 

0.1 

0X1 

tao"1 

o.i 

0X8 

*a«rJ 

(.-«) 

4 

8 A -10 

44,- 1 

8.4. -9 

M.-• 

• 

i 

14,-9 

3.1, -10 

JBA-8 

ix,-i o 

1.1,-10 

».l,-8 

4A<4 

1.8, -10 

1 

t 

Oan * 

Nl-I 

*.U1 

0,10 

ul»] 

toU) 

a(» 

1 

i.l»l 

.;"' 

'r 

2dd" J 

oxa 

ox? 

JUrf* 

U0-) 

0X8 

0X» 

0.1 

«•*) 

4 

14,-10 

14, •*) 

J4,-9 

) 

114, -10 

J 

14,- t 

J4,- • 

8X,-* 

O a * 

J'l 

»w 

aU) 

u(>) 

cJM, 

rrU) 

wtM 

H

1

'

1

'. 

1 : 

V 

0 

au . 

0.14 

04 

0.12. 

fcjO-J 

falrf"5 

OXI 

OXI 

0X0 

0X9 

* ' 

e> 

•_ 

VV 

4 

I'M! 

14, 4 

1.1,-8 

•A- * 

14, •« 

I'M 

'l 

44, rlo 

« 

,«A-» 

1 4 , -9 

IA" * 

14, -9 

• 

1 

• 

"I 

tltaWt 

-

[i] 

a,(»l 

0.O 

T.IM 

cto: 

*M 

ml»l 

i*Ul 

h 

041 

0X8 

0 X0 

0X9 

*> 

m 

• • > 

,•-

faur1 

bio*1 

0 

(.•V 

>» 

8A- W 

14,- 9 

IA- 4 

24,- 8 

• 

" 

B> 

m 

I 

14, HO 

• ••[ 

0 

n««* 

J') 

»U1 

i 

a*.-

aUl 

*M 

•JM 

•X *M 

«» 

0 

**r} 

WO-3 

**TJ 

a*r J 

td0~ S 

0X1 

0X1 

Ci) 

4 

a 

O w * 

J«l 

44, HO cJTl 

•A HO 

»AHO 

8 A -iO 

cl'l 

aW 

at') 

• • 

'• 

h 

ox*, 

oxa 

0X0 

oxs 

• 

• • ' • 

a* 

• 

,' m 

K" 

\ 

<r») 

4 

8 A- » 

14, •* 

2 A- * 

14,- 8 

• • 

• 

• 

• 

..• 

(l ] V.lia far ant crap uM d far oU crop*. In ll*u of itt: 

(2) Dtfault wlia Mu d far oil cn?.. .1 ; 

( l | I M nlui ownrd ao for Sr. 

(»| V.lunt tlam for nut «vK^>ln, (ran natubtn, fruit Mlaml i napoettmly. 

(}) So* wluo. uam l «o for Ol. 

[8) SJW tolue* Monrd 00' far ru. 

[l | S— <m\tr» U*MS ! ao for An. 

• o,-h d.M v .• 1 IT* 1 ' . I 
I \ 

I • 

TMU a n 

I 

8 

llttn l 

ta 

c.0) 

e.01 

A.OI 

8.01 

8rOI 

rr 

» 0 ) 

Ir . 

,01 

tr 

xn 

Ko 

Te 

lu 

ihO) 

M 0 I 

*8 

Cd 

i.Ol 

1.01, 

»(' . 

T.OI 

, 

1 ' o' tl.Mnt-opoelf le loot Uptake Data for Boot V.i.ta.tee, Croon Voietaetea, Croat aaa Straw 

. lOOt V«|«tialM 

c,r* 

0.18 

I ', 

1.4 (-4) 

0 

.04 1 

0.0* , 

»•« H-n 

i.» <-») 

»•«• (-J) 

0.1 4 

• .1? 

» (-*) 

j 14 (-4) 

0.10 

0.14 

j i .'«'•' (-4) 

1.1 (.-IJ 

1*1 

*rt'<8-») 

1 4 (-1) 

1.1 (-11) 

0 

»•• (-8) 

1.1 (-8) 

2.8 (-10) 

1.1, (-10) 

•».», (-10) 

J.S (-8) 

«•• ,<-*) 

7.2 (-11)\ 

I 

I.I (-U ) 

2.4 (^-S) 

*•»<-•) , 

"1.1 (-11) 

.9.1 (-10) 

• 4 (-8) " 

<V 

0.071 

1.4 (-4) 

0 

0.11 

0.089 

i.i (-1): 

J.i (-D 

t-i. (- « 

o.« 

j . l 

* . i (-J) 

1.4 (-4) 

°r°*1 

oao 

i , • . 

1.4' (-4) 

1.1 (-1) 

1,1 !' ' 

»,,(.-•) 

J.l (-») 

l.t (-11) 

0 

M <-») 

J.J (-») 

1.9 (-10) 

4.1 (-10) 

1.8 (HO) 

i.a (-8) 

4.1 (-7) 

J.l (-10) 

i.\ (-ii) 

».i (-») 

••0 (-») 

i.i (-ni 

9.8 (-10) 

,»•• (-8). 

Coroolt 

V 

1.0 

1.4 (-4) 

• 1 

0 

0.11 

0.18 

»•• (-1) 

J.l (-1) 

, 0.02* 

0.J1 V 

1W 

0.017 

i.»,W 

• ' . • ' • 

,1.0 

,0.28 ., 

' • ' i' 

i.* , <-*>' 

'i.i jt-i) 

>•*" • , . . 

*,,(.-») 

S.O (-8) 

• 

1.1 (HI ) 

''• , ' 

».• <-t) 

M (-8) 

,!.» (HO) 

4.1 (HO) 

1.1 <-») 

*lli (-8) 

1.1 (-J) 

•1.4. (-8) 

'l.V 

1.1 (HI ) 

8.0 (-8) 

1.1. (-•) 

1.1 (HI ) 

t.4 (-10) 

I.i' , (-8) 

Ora.e 

V 

0.11 

1.4 (-4) 

0 

0.12 

0.18 

J.» (- » 

1.0 (-1) 

J.l (->) 

O.M 

17 

0.01 

1.4 (-4) 

0 10 

• '.0.14 ,.; • 

1.4 ,(H ) 

!•« <-*) 

'i-i' 

W ' ) 

* •• (-t) 

i 

i.i (-in 

. 0 

t.» <-»), 

i.i (-•) 

s.t (Ho) 

8.0 (-11) 

4.1 (-10) 

1.4 (-8) 

J.0 «-«) 

l » (-»), 

1.1 (HI ) 

1.4 (,-8) 

•l. t (-8), 

1.1 (HI ) 

I • •• . 

9 4 ' (-10) 

9.4 (-8) 

8tra» 

c • 

c

sr 

O.JJ 

1.4 (-4) 

i 

0.11 

0.14 

1.4 (-1) 

1 4 (-1) 

S.O (-1) 

0.18 

w 

0.011 

1.4 (-4) 

0.11 

0.19 

1.4 (-4) 

1.1 (-1) 

1.2 " 

M<»*'> 

4.4 (-S) 

I. I (HI) , 

0 

*•*

 (t»>, 

1.1 (TS) 

1.9 (-10) 

1.1 (-10) 

• 4 (-10) 

l<»"(-S) 

1.0 (-4) 

1 4 (-9) 

1.1 (-11) 

1 4 (-8) 

J.l (-8) 

l. l (-11) 

9 4 >I0 ) 

t.4 (* ) 
TUUA4. I (Ceatlaae.) 

tl.M. t 

1 

la ., 

C« , " 

** 

u 0 1 

Ca 

Moi 

r.01 

..01 

CuOl 

«oi 

nIH 

rbOl 

.,01 

ro .._ 

In 

..01 

AcOl 

ThOl 

r.01 

uOl 

loot V*t«taklaa 

• ' cc ' • •' ar 

0.036 ', 

o •• • 

0.0)) 

8 4 (-4) 

1 4 (-J) 

J.J (-*) 

J 4 (-1) 

1 4 (-4) 

J 4 (-J) 

J 4 (-J) 

[ 1 4 (-4) 

0 

1 4 (-4) 

, 

Si<»"'> 

1 

l.S (-8) 

0 

1 4 (-9) 

J.S 1 (HI ) 

l.S (-10) 

4.1 (HI ) 

l.S (HO) 

l. l (HI ) 

I 

S.S (-10) 

l.S (HO) 

l.l (HI ) 

l.l 1 (HI ) 

' ' i ' 

ec * ir 

0.0JO 

0 

4.J (-1) 

J.O (-J) 

J-« (-J) 

1.4 (-J) 

1 4 (-J) 

1.4 (H ) 

J.» (-J) 

1 4 (-J) 

1 4 (-4) 

0 

1.4 (-4) 

*,,(.-»> 

1 4 (-S) 

•° 

14 (-lb)1 

1.4 (-10) 

l.S (HO) 

l.t (-10) 

l.S (-10) 

i , 

l.l (HI) 

t.s (-to) 

l.S (-10) 

l. l (HI ) 

i 

, 

1.1 (HI ) 

' '.' • 

Cereal* 

c.r* 

0.040. 

' o- •.••. 

O.0J4, ' 

4.0 (-1) 

J.« (-J) 

1.0 (-J) 

1.4 J-J) 

1 • < 

1.4 (-4) 

r'MI 

1.4, (-)> 

14 l(-J) 

' ' '. L 

1.4 .«-4) 

1 

0 

! 

' 

t.4 (-4) 

*fl<»-') 

4.8 (-8) 

0 

4.J (-S) 

4.8 (HO) 

l.S (-10) 

1.4 (-10) 

t . t (-10) 

l . l (-11) 

l.S (HO) 

l .t (HO) 

1.1 (HI ) 

l . l '.HI) 

1

 . 

Croat 

!

e

ir 

0.04,1 

" 0 

0.0)1 

J . l (-1) 

1 4 (- D 

J . l (-1) 

1 4 (-)) 

1.4 (-4) 

1.4 (-J) 

1.4 (-1) 

1 4 (-4) 

S 

t.4 (-4) 

1 

M<'?,» 

J.J (-*) 

o' . 

t.J <:•> 

1 4 (-S) 

l.S (->0) 

1 4 (-») 

l.S (-10) 

l. l (HI ) 

l.S (HO) 

l.S (HO) 

l.t (HI ) 

l.t (HI) 

, . i •' 

ltra» 

c.r» 

0.0*1 

'o 'v 

0.04S 

l.J (-1) 

1.4 (-J) 

J . l (-1) 

1 4 (-!> 

1.4 (-4) 

1.8 (-J) 

J 4 (-J) 

1.4 (-4) 

0 

1.4 (r4) 

»rl(.-') 

J.l (-S) 

0 

J.S (-9) 

1 4 (-9) 

1.9 (-10) 

1 4 (-9) 

1.9 (-10) 

1.1 (-11) 

1.9 (-10) 

l.S (-10) 

l.l (HI ) 

' 

1.1 (HI ) 
TA8L8 44.1 (Ceatlnuoa) 

Eloaaat 

*P 

ru 

Aa 

c-01 

c,01 

nOI 

e.0 J 

toot Voftatobltl 

c

«r 

J.O (-2) 

1.8 (-J) 

1 4 (-J) 

1.8 (-J) 

Alt'-') 

4.0 (-8)' 

1.4 (-10) 

.1.4 (HO) 

1.4 (-10) 

1 ' 

Cr... V.eetablee 

c • sr 

J.O (-2) 

1.4 (-4) 

1 4 (-J) 

1 4 (-J) 

»,,(«-'> 

4.0' (-9) 

1.1 (HI ) 

i.s (-iq) 

l.S (HO) 

Cereela 

V 

S.O ,(-1) 

i 

1.4 (-J) 

1 4 (-J) 

1 4 (-J) 

W-*) 

4.0 (-9) 

l.S (-10) 

l.S (-10) 

l.S (-10) 

Oreoe . 

i 

V 

0.82 

1.0 (-4) 

4.1 (-4) 

. ! 

4.1 (-4) 

»„(*-») 

7 4 (-8) 

1.4 (HI ) 

1.1 (HI ) 

1.1 (HI ) 

. Itro* 

V 

0.82 

J.J (-4) 

8.J (-4) 

4.S (-4) 

»rl<«-*> 

1 4 (-1) 

1 4 (-11) 

J.l (HI ) 

i • 

J . l (HI ) 

* a(-b)denotoe e i I0*fc 

• Cgp la unite ef Sq.kc*rl; fr.ah «.l|ht pl.at p*r 80,4*.-*. vet volant eell aseept (er cereal*, ukleb are aeeoaal te to proceoee4. 

( l ) Defeult oeloe. 

( l ) Velue (or, ene crop •MUM 4 (er al l crepe, 

( j ) S.a. value, a.aua.e' ee (er Ca. 

(») l.at v.tu.e e.auaea ee (or ta. 

I I 
P.70 

I 

I 

i 

1 

TABLE M. 3 

Eleaent - Specific Root Uptake Daca for Fruit 

Element 

Za 

C.WC.IU 

A." ' 

'•.w 

Br' " 

F T 

Kb 

Sr 

Y 

Zr 

Hb 

Mo. 

Tc 

Bu 

tot" 

Pd"l 

A( 

V 

0.038 

• • 

t.4(-4 ) 

0 

0.12 

0.039 

3.6(-3) 

9.5(-4> 

4.8(-3 ) 

9.5(-3) 

11 

1.9(-3) 

ll.4(-4) 

0.19 

Xr (a"') 

8.7C-10) 

3.1(-12) 

0 

3.0(-9) 

9.0(-10) 

8.0(-11) 

2.1(-11) 

-1.K-10 ) 

2.1(-10) 

4.8(-7 ) 

4.2(-11) 

3.1(-12) 

5.1(-9) 

Element 

C4 

ln< » . 

Sn"> 

Sb 

Te 

X 

X* 

Ca 

Ba 

La 

Ce 

PrMl.) 

P." ! 

Sml' l 

Eu 

Tb<2> 

C SP* 

0.39 

' " 

1.4 (-4) 

1.2(-2) 

1.2 

0.039 

0 

0.023 

6 (-3) 

3.6(-3) 

7.7<-4) 

3.6(-3) 

" 

• 

1,.4(-4) 

3.6(-3) 

3.6(-3) 

3.6(-3) 

Xr(a" 1) 

1.2(-8) 

3.K-12 ) 

2.7(-10) 

4.5X-8) 

9.0(-10) 

0 

8.8(-10) 

1.3(-10) 

8.0C-11) 

1.7(-11) 

8.0(-11) 

3.1(-12) 

• 

8.0(-11) 

e.o(-ii) 

Elvtmeac 

oy121 

W -

B i ^ 

Po 

Rn 

V

1 J 

Ac' " 

Tht'l 

P.m 

„tn 

Np 

Pu 

Aa~ 

Cm*3' 

Bk<3> 

E.<3> 

* 

C S P -

3.6(-3) 

1 

[l.4(-4) 

0 

0 

' 

i 

1.4(-4) 

0.050 

2.9(-4) 

7.7(-4) 

• 

7.7(-4) 

•:xt(s'!> 

8.0(-11) 

3.1(-12) 

0 

0 

3.1(-12) 

1.2(-9) • 

6.4(-12) 

1.7(-11) 

' 

•1.7(-11) 

a(-b) denotes a x IO-** 

-1 -t Cs p in units of Bq.kgm Cresh weight fruitzper Bq.kgm vet weight soil. 

Much of ehe daca assume same Cjp values as for green vegetables, on a dry 

weight to dry weight basis, since data specific to fruit are sparse: 

[1] Default value. 

(2) Same values assumed as for'Eu. 

[3J Same values assumed as for Am. 

63 
P.71 

TABLE A4.4 

Listing of Diet to Milk Transfer Factors for Various Nuclides** 

• Nuclides 

« ' 69M Z n 

7 7 A . 

7 5 '7 9 S a 

*

2Br 

84.8 6 R b 

89,90 S t 

90,91^ 

9 3 '9 7 Z r 

95Hb 

W Ho 

99Tc 

103,106B 

- Ru 

l05Rh 

110M,lil A 

-•• . A g 

U3H,115 C d 

123.125 S n 

125.127 s b 

12711,13111^ 

129.130J . 

"5.136 C 8 

l40Ba 

l40 L . 

,143,144 ^ 

l59Cd 

160,161 ^ 

16 Tb V 

203.2lOp b 

207 B i 

224r226 R a 

23o;23i_ y 

Th 231,233 p a 

"V 

237,239 N p 

239_ Pu 

241. 

Aa 

! 242,244 

Cm 

f * 

Al 

0.010 

4.35E-5 

3.69E-3 

1.36E-2 

1.04E-2 

1.29E-3 

1.59E-5 

8.00E-2 

1.96E-2 

9.96E-4 

9.90E-3 

5.99E-7 

6.84E-3 

2.99E-2 

1.00E-3 

1.19E-3 

2.00E-5 

1.96E-4 

9.92E-3 

7. HE- 3 

2.31E-4 

-1.41E-5 

1.33E-5 

1.04E-5 

1.98E-5 

1.66E-5 

1.02E-4 

5.00E-4 

2.90E-4 

5.00E-6 

5.00E-6 

6.10E-4 

5.00E-6 

1.00E-7 

2.00E-5 

1.99E-5 

V 

243.7 

1.62 

120 

1.48 

34 

50.5 

2.67 

3.5E8 

35.1 

2.75 

7.77E7 

39.6 

1.48 

252 

5.33E3 

129 

996 

109 

5.80E9 

8.4E8 

12.79 

V.68 

1.38 

0.775 

72. 3 

3.4 0 

2.17 

1.39E4 

3.64 

2.81E7 

1.19E7 

1.63E12 

7.81E8 

8.9E6 

1.58E5 

163 

f * 

£A2 

1.81E-3 

6.20E-5 

4.03E-3 

2.00E-2 

9.89E-3 

1.40-3 

1.98E-5 

4.04E-2 

2.00E-2 

1.40E-3 

6.09E-7 

1.00E-2 

2.75E-2 

7.68E-4 

1.12E-3 

1.70E-5 

9.35E-5 

2.85E-3 

4.79E-3 

3.50E-4 

2.00E-5 

2.00E-5 

2.00E-5 

1.82E-5 

2.00E-5 

2.59E-4 

-

4.46E-4 

3.03E-6 

4.88E-6 

-

3.86E-6 

.-

2.00E-5 

T

2

f 

0.579 

a> 

2.37E7 

• 

18.65 . 

1.06E4 

58.6 

0 . 7 

. 8a* 

m 

369 

• 

7.47 

2.2 3 

9.65 

3.8 0 

1.25 

0.517 

13. 0 

~8j» 

284.4 

. m 

6.92 

«*) 

8140 

-

5.84E5 

1.063 

11.43 

- . 

2.35-

"-•.- -

6.53E4 

1 

I 

1 

I 

I. 

•I 

1 

1 

i = 

**aE-b denocea a x 10 

* Transfer factors in units of Bq.kgm per Bq intake.day* 

t Half-live s in units of days 

- 64 -
P.72 

TABLE A4.5 

I 

I 

I 

I 

I 

I 

I 

I 

B 

1 

I 

Listing of y , K. and Stable Eleaent Transfer Factors for Milk 

Bq.kga per Bq.d kgm -1 -1 

Element 

-

Zn 

G a 1 4 1 

G e ^ 

As 

Se 

- Br 

Kr 

Rb 

Sr 

Y 

Zr 

Nb 

Mo 

Tc 

Ru •= 

Rh 

Fd'1* 

Ag 

Cd 

In[ A> 

Sn y 

Sb 

Te 

1 

Xe 

fA (milk) 

1.01E-2 

5.00E-5 

7.00E-2 

6.20E-5 

4.03E-3 

2.00E-2"

 r 

0 

. 1..11E-2 

1.40E-3 

2.00E-5 

8,00E-2 

2.00E-2 

K40E-3 

9.92E-3 

fr.-l'0E-7 

1.00E-2 \ 

1.00E-2 

3.00E-2

 : 

1.00E-3 

. 1.00E-4 

1.20E-3 

2.00E-5 

I.99E-4 

9.92E-3 

0 

f.Gnilk products) 

7.78E-2 

3.05E-4 

0.538 

4.77E-4 

3.10E-2 

0.154 

o ~ 

8.54E-2 

1.08E-2 

1.54E-4 

0.616- _ . . 

.0.15 4 . -

-1.08Er2 

7.63E-2 

4.70E-6 

7.70E-2 

7.70E-2 

.0.23, " --

7.70E-3 

7.69F.-4 

9.20E-3 

1.54E-4 

1.53E-3 

7.80E-2 

0 

Y milk 

2.6E-3 

5.0E-5 

7.0E-2 

6.2E-5 

2.5E-4 

2.0E-2 

0 

3.4E-3 

2.2E-4 

2.0E-5 

8.1E-2 

1.9E-2 

- 8.7E-4 

5.4E-3 

5.7E-7 

1.0E-2 

1.0E-2 

3.1E-2 

1.0E-3 

1.0E-4 

1.3E-3 

2.1E-5 

9.8E-5 

5.4E-3 

0 

Y ailk 

prod. 

2.0E-2 

3.8E^-4 

0.54 

4.8E-4 

1.9E-3 

0.15 

0 

2.6E-2 

1.7E-3 

1.5E-4 

0.62 

0.-15 

6.7E-3 

4.1E-2 

4.4E-6 

7.8E-2 

7.8E-2 

0.24 _ 

7.9E-3 

7.7E-4 

9.7E-3 

• -

-

J.6E-4 

7.5E-4 

4.1E-2 

0 

Si 

3.0E-6 

1.2E-5 

1.2E-5 

1.2E-5 

7.3E-7 

1.2E-5 

0 

3.5E-6 

1.9E-6 

1.2E-5 

1.2E-5 

1.1E-5 

7.2E-6 

6.3E-6 

1.1E-5 

1.2E-5 

1.2E-5 

1.2E-5 

1.2E-5 

1.2E-5 

1.2E-5 

1.2E-5 

5.7E-6 

6.3E-6 

0 

- 65 -
P.73 

Table A4.5 (Cont) 

Bq.kgm per Bq.d kgm 

-1 -1 

Eleaent fA(milk) f.(milk products) 'milk 'milk 

prod. 

Cs 

Ba 

La 

Ce 

Pr 

Nd 

Pa 

SB' 

[2] 

til 

123 

12] 

Eu 

Gd 

Tb 

Dy 

Pb 

Bi 

Po 

Rn 

Ra 

Ac 

Th 

Pa 

U 

Np 

Pu 

Am 

Cm 

Cf 

Bk 

Es 

[21 

14] 

[3] 

13] 

[3] 

7.1IE-3 

3.* •"•-4 

2.00E-5 

2.00E-5 

2.00E-5 

2.00E-5 

2.00E-5 

2.00E-5 

2.59E-4 

5.00E-4 

0 

0 

4.46E-4 

2.00E-5 

5.00E-6 

5.00E-6 

6.10E-4 

5.00E-6 

1.00E-7 

2.00E-5 

I 

I 

i 2.00E-5 

2.00E-5 

5.47E-2 

2.69E-3 

1.54E-4 

1.54E-4 

1.54E-4 

1.54E-4 

1.54E-4 

1.54E-4 

1.99E-3 

3.85E-3 

0 

0 

3.43E-3 

1.54E-4 

3.85E-5 

| 3.85E-5 

I 

j 4.69E-3 

! 3.85E-5 

7.70E-7 

1.54E-4 

1.54E-4 

• 1.54E-4 

7.8E-4 

3.7E-5 

2.0E-5 

2.0E-5 

6.0E-3 

2.8E-4 

1.5E-4 

1.5E-4 

1.3E-6 

1.2E-6 

1.1E-5 

1.1E-5 

2.0E-5 

; ) 

1.9E-5 

2.0E-5 

2.0E-5 

5.4E-5 

1.0E-4 

0 

0 

1.6E-4 

2.0E-5 

5.OE-6 

1.2E-5 

6.1E-4 

5.0E^6 

1.2E-7 

2.4E-5 

2.4E-5 

2.4E-5 

I 

i 

J.5E-4 •1.1E-5 

! 1.5E-4 

1.6E-4 

1.5E-4 

4.1E-4 

8.0E-4 

0 

0 

1. 2E-3 

1.5E-4 

I 3.9E-5 

! 9.3E-5 

4;7E-3 

3.8E-5 

9.4E-7 

1.9E-4 

1.9E-4 

1.1E-5 

1.2E-5 

1.2E-5 

2.4E-6 

2.4E-6 

0 

0 

4.1E-6 

1.2E-5 

1.2E-5 

2.9E-5 

I '*22-5 

j 1.2E-5 

i 

! 1.4E-5 

; 

j 1.4E-5 

1.4E-5 

n 

If' 9E-4 • 1.4E-5 

- 66 -
\t 

P.74 

Table A4.5 (Cont) 

* -b 

aE-b denotes axlO 

[1] Same values assumed as for Rh. 

[2] Same values assumed as for Ce. 

[3] Same values assumed as for Cm. 

-1 (4) Default value of 1 day for K, used in the calculation of Y< 

- 67 -
TABLE A4.6 

Listing of Diet to Aniiaal Product Transfer Factors for Meat and Eggs 

(Bq.kga per Bq intake per day) 

t* 

. 

-

Element 

Zn 

Ca 

Ce 

As 

Se 

Br 

Kr 

Rb 

Sr 

Y 

Zr 

Mb 

Mo 

Tc 

Ru 

R ht l 3 

Pd 

Ag 

Cd 

In 

Sn 

Sb 

Te 

I 

Xe 

Cs 

Ba 

La 

Beef 

9.8E-2?„T 

) 

• > A 

) 

8.7E-2?P 

) 

) 0 

) 

l.OE-2** 

8.1E-4? 

6.0Er3** 

2.6E-2? 

0.25? 

6.8E-3? 

l~0E-3? 

'. 2:4E-3+ 

2.4E-3? 

0 

2.0E-3? 

3.5E-4? 

) . 

) 0 -

) 

1.0E-3** 

3.0E-3? 

3.6E-3? 

0 

2.0E-2 + 

9.7E-5? 

5.0E-3** 

Pork 

0.15? 

) 

) 

0.32? 

) 

) 0 

) 

3.7E-2**b 

3.9E-2? 

2.2E-2**b 

7.4E-2?b 

0.92?b 

2.5E-2?b 

3.7E-3?b 

3.0E-21" 

3.0E-2? 

0 

7.4E-3?b 

3.0E-3? 

) 

) 0 

) 

3.7E-3**b 

l.lE-2?b 

3.3E-3? 

0 

0.25 + 

3.6E-4?b 

1.8E-2**b 

Poultry 

6.5? 

) 

> 

8.5? 

) 

) 0 

) 

2.0**b" 

3.5E-2? 

1.2**b 

3.9?b 

6.2E-3?(95Nb) 

; 0.74?(99Mo) 

6.6E-2?( 95MTe) 

7.0E-3? 

7.0E-3? 

0 

0.39?b 

0.84? 

) 

) 0 

) 

0.20**b 

1.8?( 132Te). 

0.20 + 

0 

4.4 + 

2.0E-2? 

14 ("<W 

Mutton 

4.1? 

) 

•}••-• • 

) 

l.l * 

) 

) 0 

) 

0.13**b 

2.2E-3? 

7.8E-2**b 

0.26?b 

3.3?b 

8.8E-2?b 

0.013?b 

1.5E-2* 

1.5E-2? 

0 

2.6E-2?b 

4.6E-3?b 

) 

) 0 

)

 : 

1.3E-2**b 

3.9E-2?b 

3.0E-2? 

0 

0.29? 

1.3E-3?b 

6.5^

 ,**b 

Eggs(Contents) 

2.6? 

) 

) 

9.3? 

) 

) 0 

) 

0 -

0.3? 

2.0E-3( 9 1Y)? 

0 

3.1E-3?( 9 5Nb) 

0.62?(99Mo) 

i:9?( 95M Tc) 

6.0E-31" 

6..0E-3? 

0 

0 

0.10?. 

) _ " 

) 0 . _ - • 

~) 

0 r . 

0.97?( 132Te ) 

2.8? '" 

0 

:0.45 + 

6.90? 

1.3E-2?( U OLa) 

- 68 -

Cont/.. . 
s 

TABLE A4.6 (Cont) 

1 

I 

I 

I 

I 

I 

I 

Element 

Ce 

Pr 

X4TM 

P mt 2 ] 

s.C23 

E » C 2 ] 

Cd 

Pb 

Bi 

p

» 

Rn 

Ra 

Ac" ] 

Tfr 

P . C 5 ] 

D 

«P 

Pu 

Am 

CmC4] 

Bk^3 

Beef 

2.0E-3? 

5.0E-3** 

5.0E-3 

5.0E-3 

5.02-3 

5.0E-3** 

5.0E-3 

) 

) 5.0E-3 

) 

! • 

0 

0 

7.0E-3** 

7.0E-3 

) 

) 9.3E-5* 

) 

2.1E-3* 

9.3E-5* 

2.8E-6* 

9.3E-5* 

) 

) 

) 

) 9.3E-5 

) 

) 

) 

Pork 

l.4E-2 + , 

1.8E-2**b 

1.8E-2 

1.8E-2 

1.8E-2 

1.8E-2**b 

1.8E-2 

) 

) 1.8E-2 

) 

>V 

0 

0 

2.6E-2**b 

2.6E-2 

) 

) 3.4E-4* 

) 

7.9E-3* 

3.4E-4* 

1.0E-5* 

3.4E-4* 

) 

) . 

) 

) 3.4E-4 

) 

) 

) 

Poultry 

l.OE-2? 

8.9?<l42Pr ) 

2.0?C147Nd) 

2.0E-3? 

8.9 

0.98**b 

8.9 

) 

) 8.9 

) 

) ' • 

0 

0 

1.4**b 

I - 4 

) 

) 1.8E-2* 

) 

0.42* 

1.8E-2* 

5.4E-4* 

1.8E-2* 

) 

) 

) 

) 1.8E-2 

) 

) 

••>•' " 

Mutton 

6.6E-3* 

6.5E-2**b 

6.5E-2 

6.5E-2 

6.5E-2**b 

-"6.5E-2 .. 

) 

) 6.5E-2 

) 

!•• • 

0 

0 

9.1E-2**b 

_ 9.1E-2 

) 

) K2E-3* 

) 

2.8E-2* 

1.2B-3* 

3.6E-5* 

1.2E-3* 

) 

) 

) 

) 1.2E-3 

) 

) 

) 

Eggs(Contents) 

5.0E-3 + 

9.3E-3?( 142Pr ) 

3.2E-4l( 142 5 a ) 

2.0E-2? 

9.3E-3 

1 -9.3E-3 

| 9.3E-3 

I ) 9.3E-3 

: ) 

l": 

0 

0 

•-• 0 = 

• o,: - -

2.7E-4* 

,2.3E-3* . 

4.0E-2* 

9.0E-4* 

3.0E-5*--

8.5E-3* " • 

) 

)-

) 

) 8.5S-3 

) 

) 

) 

- 69 -
P.77 

Table A4.6 (Footnotes) 

* aE-b denotes a x 10 

Cl] Same values assumed as for Ru 

[21 Where apecific values were not found, vslues for Pr were assumed 

to apply • 

[3] Same values assuaed as for Ra 

[43 Same values assuaed as for Am 

[5] Same values assuasd as for Th except for eggs 

Derived from Y and ^ values listed in Appendix 7 

f. values7from Nair et al (1980) corrected for radioactive decay 

using the dynamic model 

* 

t -

T Obtained from Mg et al (1982b). Most values are for stable nuclei. 

In a few cases, values for radionuclides were corrected for radioactive decay using the dynamic model. 

Tb Extrapolated from Ng et al (1982b) value for beef 

fp Extrapolated from Ng et al(1982b) value for pork 

** - Obtained from Simmonds and Crick (1982) "jr 

**b Extrapolated from Simmonds and Crick (1982) value for beef 

- 70 -
TABLE A4.7 

Listing of ^Values (a"') for Meat 

Element 

Zn 

Ca<" 

*»'» 

As" ' 

Se 

Br"' 

Kr 

Rb 

V 

6.0E-8* 

\ 

3.2E-8 

• 

3.6E-7* 

3.2E-8 

o 

2.3E-7* 

Element 

' i 

Sr 

* 

Zr 

Mb 

Mo 

Tc 

Ru 

Rh"l 

i 

* 

4.6E-7 

X* 

3.2E-8 

', ' * 

J.2E.-6 

1.1E-7* 

2.1E-7* 

2.9E-6* 

6.3E-8* 

1 ' 

3.2E-8 

Element 

Pd"> 

Ag 

Cd"' 

m "J 

•sa*.". 

Sb 

Te 

I 

XM 

3.2E-8 

2.1E-7* 

\ y 

3.2E-8 

1 

4.3E-J* 

4.3E-7* 

4.6E-7* 

Element 

Xe 

Cs 

»«' , 

Ls 

Ce 

Pr 

Nd<2> 

Pn^l , 

>M 

0 

1.1E-7* 

2.8E-7* 

3.4E-8* 

3.4B-8* 

3.4E-8* 

3.4E-8 

Element 

s»«2l 

Eu 

cd<2> 

Tb»2' 

Dy»2» 

Pb"> 

Po 

»M 

3.46-8 

3.4E-8* 

•', 

3.4E-8 

[3.2E-8 

0 

Element 

Rn 

Ra 

Ac<" 

Th 

Pa 

U 

Np 

Pu 

XM 

0 

3.4E-7* 

3.2E-8 

3.2E-8+ 

3.2E-8+ 

1 ' + 

3.3E-3T 

3.2E-8f 

3.2E-8 

Element 

Am 

o»<3> 

Cf1 3' 

Bk'3' 

E . ^ 

S. 

• 

3.2E-8 

( 

11] Default value used (- (year** ) . 

12] Same value assumed as for Pr. 

|3) Same value assumed as for Am. 

a 

Derived from values quoted by Simmonds and Crick (1982). 

Derived from values quoted in Appendix 5. 

' i 
TABLE A4.8 

-1, Liating of T Values for Meat (kgm ) 

Element 

Za 

Ca 

* " • , 

" 

Ss 

Br 

Kr 

Bb. / 

Sr 

V 

Zr 

Bb 

Mo 

Tc 

Ru 

Rb 

*d 

Ag 

Cd 

In 

Sn 

Sb 

Te 

I 

Ta 

Cs 

Baef 

5.1E-4 

0 

o 

0 

• 2.7E-3 

-

0 

o : 

2.0E-4 

3.2E-5 

1.7E-5 

2.0E-3 

2.4E-3 

1.2E-4 

2.5E-4 

1.3E-5 

OsvE^o 

0 

3.6E-5 

9.6E-7 

0 

0 " 

^ 3.7E-5 

1.1E-4 

1.4E-4 

0 

1.9E-4 

Pork. 

7.7E-4 

0 

0 

0 

1.OE-2 

0 

0 

7.4E-4 

1.5E-3 

6.2E-5 

7.5E-3 

8.7E-3 

4.5E-4 

9.1E-4 

1.6E-4 

=8.1E-5 

~ 9 

-1.3E-4 

-8JE-6 

'""oy 

: ? 

1.4E-4 

4.1E-4 

1.3E-4 

0 

2.4E-3 

" - -

Poultry 

3.4E-2 

0 

0 

0 

0.26 

0 

0 

3.9E-2 

1.4E-3 

3.3B-3 

0.40 

5.9E-5 

1.3E-2 

1.6E-2 

3.8E-5 

i.9E-5 

0 -

7.DE-3 

2.3E-3 

. 0 

0 

7.3E-3 

6.8E-2 

BAZ-y 

0 

4.3E-2 

' " 

Mutton -

2.1E-2 

0 

o 

0 

3;5E-2 

0 

0 

2.6E-3 

8.7E-5 

2.2E-4 

2.6E-2 

3.1E-2 

1.6E-3 

3.2E-0 

8.tE-5 

4.1E-5 

0 

4.7E^4 

T.2E-5 

0 . 

•> 

4.9E-4 

1.5E-3 

I.2E-3 

0 

2i8E-3l 

_-

Element. 

Ba 

U 

Ca 

Pr 

Nd 

Pm 

Sa 

Eii 

Gd 

Tb 

oy 

Pb 

Bi 

Po 

Rn 

R e l 

Ac 

* 

*« 

0 

Np 

Pu 

Am 

Cm 

Cf 

Bk 

Ea 

Beef 

2.3E-6 

1.3E-5 

5.9Er6 

1.5E-5 

1.5E-5 

1.5E-5 

1.5E-5 

1.5E-5 

\ 

•1.5E-5 

, 

0 

o 

0 

0 

2.0E-4 

2.0E-4 

J2.6E-7 

6.2E-6 

2.6E-7 

7.7E-9 

] 

. 

•2.6E-7 

. 

Pork 

8.5E-6 

5.4E-5 

4.0E-5 

5.4E-5 

5.4E-5 

5.4E-5 

5.4E-5 

5.3E-5 

5.4E-5 

.. 

0 

o . 

0 

0 

7.5E-4 

7.5E-4:" 

9.4E-7 

2.3E-5 

9.4E-7 

2.8E-8 

9.4E-7 

Poultry 

4.8E-4 " 

4.2E-2.T 

2.9E-5 

2.6E-2 

5.9E-3 

5.9E-6 

2.6E-2 . 

2.9E-3 

2.6E-2 

0 

o: 

0 

0 

-4.0E-2 

4.0E-2 

-

-

5.0E-5 

1.2E-3 

5.0E-5 

1.5E-6 

5.0E-5 

.-

t I 

Mutton 

3.0E-5 

1.9E-4 

1.9E-5 

1.9E-4 

1.9E-4 

1.9E-4 

1.9E-4 

1.9E-* 

1.9E-4 

0 

0 

0 

0 

2.7E-3 

2.7E=-3 

3.3E-6 

8.0E-5 i 

3.3E-6 | 

1.0E-7 ! 

i 

1 

| 3.3E-6 ! 

i 

1 

! 

- 72 -
P.80 

I 

1 

B 

1 

! 

I 

1 

1 

r 

•A 

' ^^ 

- «< 

• C :onst< rat

e < ptake 

9 

O 

O 

- a. 

10* 

•2 10** 

10-W 

10 - t l 

10 -»» 

-

i— All elements dnd-crops (except fruit) 

- - - All elements (except Cs) in fruit 

Cs in fruit 

.L 

10"4 10"3 10"1 0.1 1 

Soil to plant concentration factor CSP (Bq.kgm-'. fresh weight 

plant per Bq. kgm-'. wet weight soil ) 

FIG. AA.l.The Variation of Root Uptake Rate Constant 

Ar with the Soil to Plant Concentration 

Factor C«;P 
P.81 

APPENDIX 5 

Actlnlde Uptake to Animal Products 

- by -

Mark D. Otis and James A. Roberts 

Science Applications, Inc., Schaumburg, Illinois, USA 

The metabolism of the actinldes has been investigated primarily fo. 

rats, mice and hamsters. Extrspolatlon to large mammals Is required in order 

to estimate uptake of these elements to livestock. Such extrapolations have 

been made by each of the. reviewers cited here and, where indicated, by the 

authors* The variation In the values obtained is a result, therefore, of the 

aethods of extrapolation as well es variation In the original data. 

Considering the paucity of the original data and its manipulation, estimates 

of assimilation to muscle tissue are remarkably consistent. : 

Metabolic loss rate parameters are much more difficult to estimate. 

The values reported here reflect two general approaches. Those reviewers 

Interested ln estimating internal dose to man tend toward extremely long 

retention times in tissue in order to avoid underestimation of dose (1,2). 

Some of those interested ln modelling concentrations in food Items1 tend ~ 

toward short retention times designed to reproduce observed equilibrium, 

conditions over reasonable time scales (3). Choice of an appropriate value 

is not always clear, especially since the.data are so sparse. 

It has been assumed in the tables below that assimilation to all animal 

muscle tissues is roughly equal. No distinction has been made between beef, 

pork, mutton, or chicken where the results.have been obtained by extrapolation from rodents. The cited reviews by Ng (4,5,6) are based largely on 

observations of actual concentrations and are- so reported. However, no 

estimates of loss rates are made by Ng. 

Nothing is lost by this assuaption, since rvallable data do net support 

ahimal-speclfic values. Adjustment of the assimilation fraction for the mass 

of edible tissue appropriate to each livestock animal-giveis results 

consistent, with the available animal-specific data. Recommended tissue 

masses are presented in Table- A5.2 below* 

- 73 -
I 

I 

i 

I 

I 

Data Specification and Parameter Definitions 

For each element and food, the parameters v and X arc defined as 

follows: 

dX/dt - yl - (A + X )X 

. vhere -

X - activity ln food (Bq/kg) 

I - dally animal activity intake (Bq/day) 

T " fraction of dally Intake appearing per kg of food (kg-1) 

I X - radiological decay constant (s~l) 

X " metabolic removal rate constant («"*) 

! 

I 

I 

1 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

In addition, some parameters used ln the discussion below are defined 

here as follows: 

Tf - ratio of concentration in meat to the animal's daily activity 

Intake 

\TqfiL " Kg*J •:.' 

f_ - assimilation fraction to meat (unitless). 

m - mass of edible-tissue per animal (kg) 

The 'parameters f and. y are related by: 

y-± 

Because the units of Inverse seconds do not lend themselves to easy 

.intuitive grasp, the blologlcsl half-time, T , in days, is also included In 

the tables below. The quantity T Is defined aa follows: _---".-

Tn(d) - —^ > 

B

1 ' X x 8.64(4) s/d 

- 74 -
Uptake and Retention ln Animal Products 

Two related types of uptake and retention data are reported ln Table 

A5.1 below. The first type consists of the unltless assimilation fraction to 

muscle tissue, f_, which is associated with a biological half-life, T_(d), 

and a metabolic rate loss constant, X (s**1). The second type is the 

-_ m 

equilibrium tranafer coefficient, F (d/kg), relating concentration In tissue 

to daily intake. F is not associated with a loss rate estimate. In order 

to compare these two quantities, an effective transfer coefficient, F_, has 

been calculated for each reported f_ and X. pair. This calculation was done 

B a 

in the following manner. 

The solution of the differential equation given above (neglecting radio-, 

active decay) is: 

"xct-y -"".?(i -•"V> 

_ a 

the ratio of the tissue concentration to dally activity Intake Is then given 

by: 

x(t) Y ,, yk t. 

sinc e - _=• 

'*?••;• • .'y-y- -

and •.-"•-..- " 

this is equivalent to: 

iiH - F -

 fB, . (1-e-V) I

 rf m x X KL^ " ' 

a 

F, values reported by Ng are Intended to reflect transfer at equilibrium." ~ 

-It is clear, however, that the long biological half-times reported fpr some 

sctlnides preclude an equilibrium for realistic feedJag times.- An integration time of one year was chosen in calculating F. from y and X . 

r m 

It should be emphasized that this is an arbitrary choice made to allow 

comparison of two types of data. Since,, for long T_, F. Is proportional to t, 

integration times of three years would raise some calculated F. values by a 

- 75 -
P.84 

factor of three; integration to 120 d would decrease soae calculated F.'s by a 

| factor of three. For short T_, of course, the calculated F, is relatively 

" insensitive to integration tlae. The value of a was taken to be 180 kg for 

comparison with values reported by Ng for beef. It is felt by the authors 

that slallarlty of a calculated F. with F_ values reported by Ng, particularly 

the aost recent.values (6); is a possible criterion for choosing a Y and X 

• a 

pair for use in an assessment code. 

The f and X "values chosen aay be used for any animal.when the 

• B . m 

appropriate mass is used to give the correct Y . Typical aucle mass values 

for cattle, swine, sheep, and chickens are presented In Table A5.2* 

The parameter values given below are the result of manipulation to 

various degrees since the specified mathematical formulation differs somewhat 

froa that used by each pf the reviewers cited* Numbers are given to two 

significant places followed by the power of ten ln parentheses. 

I 

I 

I 

I 

I 

I 

r 

i 

i 

i 

- /6 -
P.85 

Table A5.1 

Animal Metabolic Parameters 

Element 

Th 

Pa 

U 

Up 

Pu 

' 

-

Am, Cm 

*B 

4.0 (-5) 

5.0 (-5) 

3.5 (-4) 

5.0 (-5) 

6.0 (-3) 

2.6 (-3) 

1.2 (-3) 

-

4.5 (-3) 

5.0 (-5) 

6.8 (-3) 

4.2 (-4) 

4.5 (-6) 

1.5 (-6) 

5.0 (-6) 

4.2 (-7) 

2.3 (-4) 

5.0 (-5) 

2.1 (-5) 

: , -

TB(d) 

7.0 (+2) 

3.7 (+4) 

1.0 (+1) 

3.7 (+4) 

6.0 (40) 

1.2 (+1) 

5.0 (+3) 

_ 

1.5 (+4) 

3.7 (+4) 

3.9 (4*) 

5.6 (+3) 

1.5 <+4) 

3.7_(+4) 

2.5 v+1) 

5.6 (+3) -

-

1*5 (+4) 

3.7 (+4) 

5.6 (+3) 

-

V

8"1) 

1.1' (-8) 

2.2 (-10) 

8.0 (- 7) 

2.2 (-10) 

1.3 (- 6) 

6.7 (- 7) 

1.6 (- 9) 

- •' 

5.3 (-10) 

2.2 (-10) 

2.1 (-10) 

1.4 (-9) 

5.3 (-10) 

2.2 (-10) 

3.2 (- 7) 

1.4 (- 9) 

5.3 (-10) 

2.2 (-10) 

1.4 (- 9) 

; -

PfCjqr)* References 

(at 1 year) 

6.8 (-5) 2 

1.0 (-4) 1 

2.8 (-5) 2 

1.0 (^4) 1 

2.9 (-4) 2 

2.5 (-4) 7 

2;4 (-3) 1 

3.7 (-2) 6 

9.3 (-3) 2 

1.0 (-4) 1 

1.4 (-2) 3 

8.3 (-4) 7 

2.0 (-4) 6 

S.3 (-6) 2 

3.1 (-6) 1 

1.0 (-6) 3 

8.3 (-7) 7 

8.0 (-7) 4 

1.0 (-6) 5 

2.0 (-6) 6 

4.8 (-4) 2 

1.0 (-4) I 

4.2 (-5) 7 

1.6 (-6) 4 

3.6 (-6) 5 . 

•Calculated by authors for-beef, based on 180 kg/cow, assumed 365 d 

feeding period, or reported by Ng et al. (reference 4, 5, 6). 

- 77 -
P.86 

I 

I 

I 

I 

i 

I 

I 

Table AS.2 

Recommended Muscle Mass for Various Animals I 

I Animal Mass of Edible Tissue (kg) 

I 

I : •:':•' . 

Cam 180 

Pig *° 

Sheep 15 

Chicken 1 

Transfer to Eggs 

• ' . • ' -- - All reported values "for eggs are based on measurements ln chickens or 

extrapolated by the.authors. It-was assumed, when no other data were 

I available, that the ratio of assimilation ni the-given nuclide to that of 

plutonltm would be the saae for poultry as for aaamals. The ratios used for 

I

scaling of poultry plutonium data were derived froa asslallatlon fractions 

given by ICRP 30. 

Asslallatlon fractions to eggs are reported for egg contents not 

g " including the shell. No values for aetabolle loss rates froa eggs'are given 

hire. Since egg contents are not metabolizing tissues it is assuaed that 

I .. loss is by radioactive decay only. 

Transfer, coefficients~ for eggs are generally derived ln the - following 

aanner: 

. :>.-±-:\yyy . 

where F " transfer coefficient to eggs Cr-) 

f - fraction of activity ingested going to eggs (unltless) 

n — - _-

P • egg production, rate-(kg/d) 

Concentration'In eggs may be calculated by: 

X(t) - I(t) x-F- - _

 : 

-•3 

where X(t) • concentration in eggs at time t (Bq/kg) 

I(t) - activity ingestion rate at time t (Bq/kg) 

- 78 -
P.87 

This is the recommended use for the transfer coefficients presented ln Table 

A5.3. If it is necessary to use a model similar to that described above for 

meat, the following reasoning may apply. 

fB fB Let F - ~ - . (P - m x X ) 

e P a x X a • 

•••_• _ 

The. production rate for eggs, P, is approxiaately 0.023 kg/d. If it is 

assuaed that the tissue..mass of Interest, m (egg contents), is maintained 

homeostatically at 0.023 kg by a hen's aetabollsm, and that equilibrium 

between feed and eggs is rapidly established, X aay be arbitrarily taken to 

be 1/d. 

Then f _ • F -x F B e 

AA 

and 

X.4x d * 8.64(4)s 

- 79 -
P.88 

II • 

i 

Table AS.3 

I Paraaeters for Eggs 

I 

I 

I 

Ptt 3.0 (-5) 6 

1

9>9 (-5) 3 

7.7 (-5) 

Nuclide Transfer Coefficient Reference 

- (d/kg) 

Th 2.7 (-4) .'*."'•' 

Pa , 2.3 (-3) * 

0 4.0 (-2) * 

Up 9.0 (-4) 3 

I 

4 

3.3 (-5) 5 

Aa, Ca 1.5 (-3) * 

8.5 (-3) 6 

5.0 (-3) 4 

3.9 (-3) 5 

* Extrapolation by authors 

- 80 -
P.89 

References 

Dunning, D.E., Bernard, S.fc., Walsh, P.J., Killough, G.G., Pleasant, 

J.C, 1979, "Estimate of internal dose equivalent to 22 target organs for 

radionuclides occurring In routine releases from nuclear fuel cycle 

facilities", 0RNL/TM-190/V2, Oak Ridge National Laboratory, Oak Ridge, 

TN. 

International Commission on Radiological Protection, 1978, "Limits for 

intakes of radionuclides by workers", ICRP 30, Parts 1, 2, and 3, 

Pergamaon Press, Oxford. 

3. Kirchner, T.B., Whicker, F.W., Otis, M.D., 1982, "PATHWAY: A simulation 

aodel of radionuclide transport through agricultural foodehaina", 

Proceedings of the third International conference on state-of-the-art ln 

ecological aodelllng, Colorado State University, May 24-28, 1982. 

-4. Ng, T.C, Phillips, W.A., Rlcker, Y.E., Tandy, R.T., Thoapson, S.E., 

1978. "Methodology for assessing dose commitment to individuals ani to 

the population froa Ingestion of terrestrial foods contaminated by 

emissions froa a nuclear fuel reprocessing plant at the Savannah River 

Plant", UCID-17743, Lawrence Livermore National Laboratory, Livermore, 

CA." 

It'"'". - - -•...' . 

j 5. Ng, T.C, Colsher, C.S., and Thompson, S.E., 1979, "Transfer coefficients 

for terrestrial foodchain - their derivation and limitations". Preprint 

UCRL-81640, Lawrence Livermore National Laboratory, Livermore, CA. 

6. Ng, T.C, Colsher, C.S., Thompson, S.E., 1982, "Transfer coefficients for 

assessing the dose from radionuclides in meat and eggs", UCID-19464,- _ 

Lawrence Livermore National -Laboratory, Livermore, CA. 

7. Siaaonds, J.R., Crick, M.J., 1982, "Transfer parameters for use In 

terrestrial foodchain models", NRPB M63, National Radiological Protection 

Board, Chilton, Dideot, Oxon. 

- 81 -
P.90 

I 

I 

a 

I 

1 

I 

I 

Dry + wet deposition 

from plume 

Inhalation 

of plume 

field loss 

egetation 

Soil 

I ingestion 

Soil 

Root uptake 

Animal 

intake 

of 

herbage, 

silage, 

concentrates 

Livestock 

ExcretionSlow 

Downward 

Migration 

Water 

table 

Vegetables 

cereals .fruit 

Man 

Milk, meat 

eggs 

FIG.1. Schematic Representation of Terrestrial 

Foodchain Transfer Mechanisms. 

*. * 
P.91 

Plant 

(Edible / non-edible ) 

Urc 

Surface 

(S) 

Field 

loss 

8» 

Translocation E/ Root 

Tissue W ake | 

(T) 

Plant 1 

base uptake J 

Deposition 

from plumD e 

Plant 

Base 

(PB) 

Labile 

surface 

soil (LSS) 

I 

Labile 

deep 

soil (LDS) 

(Not for root vegetables) 

Concentratio 

in food at 

Harvest 

fixed 

surface 

soil (FSS) 

I 

Fixation 

Fixed 

deep 

soil(FDS) 

Soil 

To water 

table 

/Concentration^ 

in food after 

Processing & 

Storage 

Level in 

surface 

soil 

FIG. 2. Dynamic Model for Crops. 
P.92 

I 

I 

I 

I 

I 

I 

Grass 

Average level 

in grass over 

timestep 

Average level 

in soil over 

timestep 

S —i . • -

T^ 

T y| 

i 

PB - • 

|LSS^: 

LDS — 

^ -

-

r-Fss 

•— FDS 

y 

_ 

\ 

-

Animal 

intake -per 

day 

Average level 

in straw over 

timestep 

Level in hay/ 

silage after storage^ 

& compaction 

Animal 

product level 

after processing/ 

and storage 

Animal 

product K Animal 

product level 

for raw product/ 

1

Biological 

removal 

Level in straw• 

after storage &, 

compaction 

Straw 

FIG. 3. Dynamic Model for Anima l Products . 

(See FIG.2.for definition of compartment labels) 
P.93 

E 

_c 

l a 

k 

Wl 

19 

• 0 

so 

to 

30 

M 

to 

• • 

(a) 

» 

» 

n 

I}}-

t( 

!» 

'/ki 

tri \ Y_ 

'/ V*^v^^ 

# * ^-..N.-." / 

* 

• 

< 

tX 

• 

i 

a 

v *•* 

•»J 

u 

M 5 

o 20 a 

• ? 

• silky. 

-—Recorded 

deposition 

(pCim-> d"«) 

—Recorded 

activity in milk 

(pCi I"') 

90S 

£ 

e 

Z*i 

»»- SI U I I IT H 

Tear 

FIG.4. Quarterly Averdoe Fallout Deposition Rates and Country-wide 

Average Activity Levels in Milk of (a) ^S r and (b)l37Cs in the 

U.K. 1958-1978. 

300 

300 

litoo 

18 80 -82 8* 88 88 70 72 74 70 70 

(b>: 

. 

' __ -

H % 

** — il: -

'W = 'Ai •/: te 

h \\ V \ £ \;~ 

• 

_ 

•—-w 

JS**. 

'*-- Recorded 

activity in milk 

(pCi I' M 

— — Activity initially 

predicted by 

model (pCi lH) 

Activity fina'ly 

predicted by 

model 

»» 01 S3 SS (7 CS 71 73 75 77 

Year 

FIG.5. Comparison of Recorded Levels of (a)

 90Sr and (b) 137Cs 

in Milk with Levels Predicted bv the Model. 
P.94 

l 

l 

l (a) 

.to • 9°Sr 

9.A 

£ *4 rSy\ 

>» 30 

'»..'"* ^ 

I 

t 

» — • ' \ 

tiee y f -'r-r- v 

o 

o 

M CO 03 04 M CS 70 73 74 7C 78 

>t Cl S3 Ct C7 Ct t l 79 Tt 77 

Year 

FIG.6. Contributions to (a)

 90Sr and (b) 137Cs -

Activity in Milk from (—*_—) Plant Surface. 

( -) Internal Plant and•(-•••••••.) Soil. 
P.96 

f "•*• 

! 

• f 

i-vw 

m 

*,.-

\ 

M 

X 

.• ~«-

X 

9 

_g 

\Ora« « 

A i 

\ ^ 

!•* A 5 -H 

\ \ 

Na»\ \ 

»*a»\A\^ 

*"* N \ "" 

- NfawHffs^ 

-r»*"~ 

. mils' 

Oar» 

-

w 

_• 

" ' • 

0«T* 4t*t «ta 1 tMmfltm 

i 

J 

•t 

t 

• 

• n 

. \ 

a.M ' 

" i • -

Graft -

Mill 

*—< 

__3 

• 

3*. 

m i . 

• ^ 

a » 

Oar* 

" 

p- ~ ^«*~" 

\__\ 

**+ 

(.101 

Day* 

' LOT* «I tint nar.*M 

Xt» im •wammiii 

han.M* 

Oay* txtt tt* « ow.vt.wi -- Oar Oar** al* ana"r •« tn t • •* awaartia* MM M 0«r» aixt MM M IWI- W 

FIG. 7. Result* ot Somple Colculotions Using the Ovnomie Model. 
P.97 

II 

l i 

I 

r . * 

5 * 

" *" - _t "•»», _ 8>88tTSISOSBT 8** 

•«^ -

y 

i.a taa.i taav.a »iaa.i* 

Figure 8(a): Tlie discribucion of production of potatoes in Scotland 
^ 

1 * 

SjSJ«a>H JK«<lf»JS;..-1b<««aa>a>an 

Figure 8(b): The discribucion of produccion of pocatoes in England and Wales 

t 

I 

1 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

e 

i 
P.99 

^ 

,1 

.1 

I 

a»a»a»aa A. . 

Figure 9(a): The distribution of production of green vegetables in Scotland 
p.1 

AS ' T_\ 

paa •«•*. • aiufia a i 

WKR"! ^it-JC-i.T* *8»8t* 8 ••y?* V ••••••• • 

l*\* *t» " 888W88 8 +2AP7**% 888 VC-alZl. * w ' 8»88>88 8 

•Mi l 111- 8M—88 8 

Figure 9(b): The discribucion of produccion of green vegetables in England 

and Wales 
I 

P.2 

I 

Figure 10: The distribution of production of fruit in England and Wales 

(No data for Scotland) 
P.3 

isutKw*"*""* -

igjlipiiil 

^pijjjkgpapilPH •" 

mm , 

• K::Ka 

SsT •n?siH-JSn«h-:Hn:i«HI»HUiHiiL-?SHSK»n^ 

• 3 5 

R:.taE:5h ^nZH:^;0fcj 

fy;nTi.***HiCri "iv»"rTT** f^*if" 115**•-'•""'• "7" aaWSj^^i' 

Figure 11(a): The discribucion of produccion of cereals in Scocland 
I 

PA 

I 

I 

I 

I 

I 

Figure 11(b): The distribution of production of cereals and England and Wales 
P.5 

3 

s:;;ngu..um 

p i ? 

wwiaH^^:-jrr:i3*3^!fiSt-*1 

Wtj;-;:-:nu.-::E: 

H$ 

SiSP 

m:nj|«h n tn;.i.:i -^iir::- -.J.- K -. v 

T?:*"m -% . ' u:Jr~£Hnn:Kurn :~2'£ ;;ci;"-K: 

•t'tiTt „ .inn*. ^*j:n:-*uiJyiii:: r*;"rti":::.truKiir" ••*• — — 

JrtWj.:in; 3-j|*;tt;;^:Ks:.w«^;w.w:^ 

ii. 

3:H£ 

IP": 

-T1 ;&3lj|-f HHi^HTaTr KLl^in UK «*:::*:a«;H::.A. . 3 t —* —• 

_• *-*• .••»«»*.••=•'»•.?".»•• *._ 

feH»nr-:r?n~'"" 

jjtSK::::*tuttui"tVT:_jjjj3^p. ::I;s^jrtui':i; ".Tnt. :.;*.: rrt:**::*i:: 

• _ 5 qp4s^agigjjgB~i> "•-=;:-J 

"*

 !SL...... _.-,_.-, 

-i ?31r&£!:--^3:ii::;;:.::ir 

Tr1 

Figure 12(a): The distribution of production of milk in Scocland 
_Ei 

:JST?a 

m 

m 

Figure 12(b): The distribution of production of milk in England and Wales 
P.7 

.gSiSvS' 

.i&3S? 

ruUiinas-^- =.K:nr 

n*"*tll*^;n" UU "**7I*1 & IZZ'X* ,H *T'li'ii! T* i*.!'T"? '* •••» • ' 

-:i«-£r **«;:i::?:m;:;*::— s:uftn»:K!-k:.::i I-WV^I W 

*^--*i^j|r ^l^g^p^jj^'g^^g^gg; ^ ^ 

"~ "js^T^S^H:" ^H*5^i 

.•£3iw.r~ "^~" __ _ 

_gS J^CS_^i^^tm^SlAx»SS_^Sr**-

~ g^!^il§^=J!Spi='a{|Q**l*tT.1^"^

 3=

-

n|ll§r IpaivtP 

~3~ ~:=«i=3 ^SSiVwf^SSSSSBitrrli^ 

• • . •>• .VT * 1:"a»85faV: 

K;KU.:SI*S S&3»iV? ••••••• • 

nr:::r::-KK •V.**^*?! 88>»n»8 

Figure 13(a): The discribucion of produccion of beef and veal in Scocland 

1 

l 
P.8 

I 

I 

:«*aa»a-'»**-<jg83a*M"»»Oa>SId<>»l^%J*-jr' » «TB? ^1»*ai>»»'l ' .»* : laaaaaill . 

— xoi ——*«-4.S «*M " " M*aO«aO^»fgay.a.ajl>8jgjV|.. 

?ar 

Figure 13(b): The distribution of produccion of beef and veal in 

England and Wales 

1 
' "k 

P.9 

wuy n u 

scanSH:!H 

n"2rH:T ;sH?K:i:!H:«nU:I itkuHiHHs 

^IsS UUKUt: 

K£J~sn~^ii"2i3Hi^U3*>ii":li^ 

iTiSi-y. _r.:-:n" :-:::'::.• ^IiCgPT*"H«i=^*:i-:"=HS:i^.1"y*' 

:

is!Ufi!;«;!!ffi|iH^sflREi; 

Siu[L:i5j:j*:j.;K' ,l^^;:3K::^ 

I 

vl 

i 

.1 

J 

ii 

il 

r.m: • 

I Figure 14(a): The distribution of production of pork, bacon and haa in 

Scotland 

I! 
P.10 

I y 

I 

I 

a 

iiii 

i 

I 

•i 

Figure 14(b): The distribution of production of pork, bacon and ham 

in England and Wales 
-P-JLL 

-^*r TPT 

y 

L?K-:^ 

r • mtwi— I 

• -»•-?. . :a?..*.*** - 888P888 8 

1 •>.• •».* !•».• 

Figure 15(a): The discribucion of produccion of poultrymeat in Scocland 
P.12 

I ~y 

I 

I 

a 

s 

a 

r 

i 

i 

dsKMfcs s^-i&£^ir?A^*A-z~A2i___if'm-•••:*»; a*^ 

Figure 15(b): The distribution of production of poulcrymeac in England 

and Wales 

I 
P.13 

1 

y 

a 

i 

;:r; •x..«"kriri. I— z^-.z-tr "V- •~i.:

tri~Z-'"-^JiJ^Br-'^' 

:**>.y*+*mBa»?: •.: _• «——'• 

~j_m'-i*-*e? 

Figure 16(b): The distribution of produccion of eggs in England and Wales 
P.14 

^ 

irir^nih:!1! sj"S£ 3 ::: 

£^i;:*"":Ta t^StTZt ft. 

Figure 17(a): The distribution of production of mutton and lamb in 

Scotland 
P.15 

I I 

• i 

n 

I 

i 

i 

i 

! 

I 

I 

I r 

I! 

I 

I 

ii 

ilII 

y 

o3S*/y ••*»_»•' T t— •--•i'.'i'S-'• "••fO* f. •» £*»•• 

Vi.-,*. .-li?*-*iS?!ir ^ :••'••-•.: iff :: • 

Figure 17(b): The distribution of production of mutton and lamb in 

England and Wiles 
P.16 

^ 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

I 

Centra. Bectricity Generating Board 

Berkeley Nuclear Laboratories 

CEGB UNRESTRICTED RD/B/5200/N84 

Job No. XB022 

Models for the Evaluation-of Ingestion Doses Froa the Consumption of 

Terrestrial Foods Folloving an Atmospheric Radioactive Release 

A . A ; --by-" 

• •- S. Nair 

April 1984 : 

STJMKAHT y 

In this report various methods are described which have been incorporated In the" FOODWEB module of the CEGBV NECTARzenvironmental code and are 

currently being used within CECB to assess Ingestion doses from consumption 

of terrestrial foods following!an atmospheric radioactive release. The major 

steps In such an assessment are: 

. - (1) the calculation of nuclide concentration levels in various foods 

arising froa a known deposition froa the plume, 

(11) the calculation of the corresponding individual and population 

.doses arising from consumption of these foods. 

Of these, the first is the most complex and is achieved via the use of 

an appropriate -foodchain model.' Four such models have been developed within 

CECB, namely: -.-.'•• • 

(1) a general, -dynamic model covering a.wide range of foodchain 

pathways, which may be used to study the time-dependence of radionuclide 

transfer for both continuous and accidental releases of mixtures of 

radionuclides in decay chains at different seasons of the. year, 

(11) a simple, equilibrium model covering a limited number of foodchain 

pathways, which may be used only for a continuous release of a single parent 

nuclide, 

(111) two "special case" models, respectively for studying the transfer 

of trltiua and

 1'*C froa continuous releases of trltiated water and 

labelled CO.. 
P.17 

I 

I 

•! 

i 

•i 

i, 

i 

i 

^ v 

These aodels are fully described and results of typical calculations 

presented. Also given are the results of a validation of the dynaalc model 

against measured

 90Sr and 137Cs levels In allk ln the D.K. resulting froa . 

weapons fallout• 

Finally, aethods are also described In this report for calculating 

Individual and population doses froa Ingestion using the results;of the.aodel 

calculations. The population dose calculations utilise a data base 

describing the. spatial distribution of production of a wide range of 

agricultural products. Tbe develppaent of such a data base for Great Britain 

Is described, based on the 1972 land use and livestock census, and asps are 

presented for each agricultural product. ~ 

Content Classification and Distribution 

Approved Appro? 

4g££--

CJU (**s 

Date:. iVkfa ^ Date: 3o|s>(8<f