?C i EG9601917

AREAEA/Rep.324

ARAB REPUBLIC OF EGYPTATOMIC ENERGY AUTHORITY

NUCLEAR RESEARCH CENTER

USE OF INORGANIC AND ORGANIC COMPOUNDS ASDfeCON lAftfHNANTS \rOH COBAL 1 - 60 AND BY

CLOVER PLANT GROWN ON INSHAS SAVDY SOIL

BYM.F. ABDEL - SABQUR, H.A. EL NAGGH , S.M. SULIMAN

SCIENTIFIC INFORMATION 8. DUCUMENTATION CENTERATOMIC ENbRfeY POS1 OFFICE

CAIRO. EGYPT

1

A.R.E.A.E.A/Rep.No.324

ARAB REPUBLIC OF EGYPTATOMIC ENERGY AUTHORITY

NUCLEAR RESEARCH CENTER

USE OF INORGANIC AND ORGANIC COMPOUNDS AS DECONTAMINANTSFOR COBALT-60 & CESIUM-134By CLOVER PLANT

GROWN ON INSHAS SANDY SOIL

BYM.F.ABDEL-SABOUR, H A EL-NAGGR

S.M. SOLIMAN

1994INFORMATION AND DUCUMENTATION CENTER

ATOMIC ENERGY POST OFFICECAIRO, A.R.E

CONTENTS

Pages

ABSTRACT i

INTRODUCTION 1

THEORITICAL BASIS 2

EXPERIMENTAL 3

RESULTS AND DISCUSSION 4

4.1 Effect of Oganic and Inorganic Salts on Dry.. 4

4.2 Effect of Organic and Inorganic Compounds.... 5

4.3 Effect of Organic and Inorganic Compounds ... 6

4.4.Cobalt and Cesium Accumulation Parameters.••• 7

4.5 Cobalt and Cs Availability or Retardation.... 7

4.6 The Effect of Applied Compounds on 8

REFERENCES 9

ABSTRACT

Outdoor lysiraeter experiment was carried out to elucidate

the effect of four inorganic and three organic salts on °0Co and^Cs

uptake and dry matter yeild of three cuts of clover in the soil Inshas

A new concept was proposed for assessing the difference in capacity

of soil to suppliy radionclides (i.e. °"Co and *-^Cs) to plants as

affected by applied inorganic or organic compounds. The relation of plant

tissus (Pc) Co/ir Cs content with increasing time can be expressed as log

(Pc) = A + B log time (T), where A and B the regression. When the same

plant species is grown on the same soil differ only in the applied comp-

ound (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO)z, A1(OH)3, Ca(H2PO4)2 and

Fe2O3) the equation will change to, log (P'c) = A" + Bf log (T) (I). Based

on both equations, the relationship between (P'c) and (Pc.) becomes; log

(P'c) =[(A'B')/(A"B + AB")[ + [1/A'B + AB")[ log (Pc) (II). The intercep

(C) and slope (S) in Eq. (II) were determined among 7 treatments (for either

60 Co or l^Cs). Then the difference of either Co or Cs accumulation with

time between control and any other treatment was evaluated according to (C)

and (S) values

The data also show that Fe-DTPA is preferred for o<^Co as enhancing

compound for plant uptake (for decontamination use); compared with other

applied salts; on the other hand, any tested salts did not significantly

effect 1-^Cs taken by clover. Also, it was found that more than 70% of :

total cobalt uptake was accumulated in the roots which indicate that Co :_

is less mobile in plants than Cs.

1. INTRODUCTION

It is now well recognized that the growth of nuclear

energy industry during this century has led to an enhance-

ment of the levels of nuclear radioactive wastes in the en-

vironment,. There are several pathways for the potentially

harmful substances to enter the food chain* One of these

pathways is through the soil, after the radionuclides tran-

sfer into the environment in the form of smokes, dusts and

leachate. The Chernobyl tragedy in 1986 is a clear example

which vivid a reminder that radioactive fallout poses a threat

to human life, health and food trade even without the explosion

of the nuclear weapons, a threat that does not respect nation-

al boundaries.

Cobelt-60 and Cs are among the radionuclides associ-

ated with nuclear activity and their release to the environ-

ment is of great concern. An understanding of the interac-

tion between such radionuclides and the soil requires con-

sideration of both the physico-chemical properties of the

radioisotopes and those of the major components of the soil

system. The source of the radionuclide can greatly affect

their subsequent behaviour in the environment and merits

detailed description (1)

Cobalt is of biological significance because it forms

organic complexes under favourable conditions and is incorpo-

rated in suspended matter by sorption reaction. Cesium is

strongly sorbed in ion exchange (2) and may be fixed as would

be often with radionuclide contamination (3),

- 2 -

2. THEORITICAL BASIS

At specific time plant tissue Co/or Cs (Pc) in the same

plant species grown on two different treated soil will di-

ffer usually in their co/or Cs content according to the fac-

tors effect metal availability and plant absorption for the

studied elements* Assuming that, under controlled experi-

mental condition, these factors are only affected by the

applied treatments. Under this assumption Co/or Cs accumla-

tion curve can be generally expressed as; Log (PgJ-^A + B

log time (T), where A and B are the regression coefficients,

and which are here referred to as Co and/or Cs accumulation

parameters. The accumulation parameters of A and B would

be affected by various factors of a plant-soil system. In

this study we investigate the affect of various organic and

inorganic compounds applied to sand soil polluted with either

°Co or Cs. Hence, the Eq (I) and in a similar manner,

that curve for the second treatment can be expressed as;

log (P, C ) ~ A W B^ log (T) (I), based on both equations,

the relationship between (P'c) and (Pc) becomes;log (P'c)^

(A'B*)/(A'B + AB*) + 1/(A'B • A£) log (Pc) (II).

log (P'c) -(JA'B')/(A'O • AB'}]* £l/(A'B + AB') log (PcjQ(III). This equation indicates that the Values of (P'c) are

logarithmically related to those of (Pc) via the accumulation

parameters. The intercept (C) and the slope (S) could be

used as a comparative availability (or retardation) parameters,

The aim of the present investigation is to study the

uptak ;of °Co and Cs by clover plants as affected by di-

fferent applied compounds (organic and inorganic) to sandy

soil and to show the possibility of soil decontamination or

to what extent the addition of such compounds could inhibit

the translocation of radionuclides to growing plants.

- 3 -

3. EXPERIMENTAL

Out door experiment was conducted in sixteen lysimeters,

60 era in diameter and 45 cm high filled with sandy loam

soil from Inshas area with exchange capacity of 1.4 mel. q/lOOg,

5% clay content, poor in organic matter (0.19%), and soil

pH of 7.5. A sub-plots were conducted in the centre of each

lysiraeter; 10 kg soil packed in plastic bag for isotopes app-

lication. In order to maintain as adequate supply of N, P,

and K each lysimeter received 100 kg N/Fedan (acer ) as ammon-

ium sulphate, 150 kg P/Fed.. as calcium superphosphate, and

100 kg K/fed. as potassium sulphate

Ten grams clover seeds were sown in each lysimeter. After

germination, the lysimeters were divided to two division,the

first division received CoSo, solution and the other received

CsCl at a constant rate of 10 M. In addition, each group of

lysimeters have received different solutions at constant rate

(10 ~4M) as follow: Fe-DTPA, Fe-EDDHA, FeQAC, Fe (C00)2> Fe203

Al (OH), and Ca(H P0*)?* T n e control in each group received

only distilled water. The subplot of each lysimeter were iden-

tically trerted as mentioned above except Co or Cs solutions

were labelled with Co or cS at constant activities. The

soil moisture content was maintained at 60% WHG. The plant

shoots were consecutively harvested after 44, 90 and 121 days

of planting, then the roots were taken by screening the soil.

All samples were washed dried, weighed^ground and digested

using wet ashing procedure (4). The activity of either

or •'•3'4GQ was determined using a RST Gamma counter..

- 4 -

4. RESULTS AND DISCUSSION

4.1 j|jJij»^J>JfLjO.^P r oduj t ion.

The data in Tab. 1 shows the effect of applied compoundshaving the same level and activity of Co or Cs, on the dryweight of clover. Dry matter yield varied widely in respectto plant growth stage and applied salts. The application ofFeOAC increased the cumulative dry matter compared to the con-trol. On contrary the application of Al (OH), and FeEDDHAsignificantly decreased the dry matter yield as compared tothe control samples.

Regarding the yield parameter Tab.2 from the regressionequationm the effect of applied compounds showed inconsistentpattern. The only remarkable observation was a slightlyhigher yield parameters which was obtained, in case of the organiccompund treatments (except with Fe (CQ0)2 treatment) ascompared with the inorganic compounds for both studied elements

The data reported in Tab.l shows that the roots dry matter

yield of clover was negatively affected by the applied treat-

ments with two exceptional cases, the FeOAC and Ca (H2P04)_

treatments.

- 5 -

4 . 2 . jJtf j f j j^LJ9JLJLri l3gicJJl^^JlSrP8"^0 PomP.oun9'sl. .01 P.P.Uptake^

The uptake of Co (through 3 time intervals) by clover

as affected by organic and inorganic compounds, were calcula-

ted and given in Tab. (1 and 3) and Fig.l. The data show

that all organic and inorganic compounds, except FeOAC, in-40creased Co uptake in all cuts, compared to control. The

highest values were associated with Fe-DTPA treatment in all

cuts. Also, the decrease of Co uptake between first and

second cut could be attributed to the accumulation of dry

matter (dilution effect). Cobelt uptake, as percent of appli-

ed activity, varied between 0.04 to 2.75% , the highest was

associated with Fe-DTPA in all cuts. Tab.(3).

Regarding the effect of different compounds on Co

uptake by clover roots, Tab.(l) showed that Co accumulation

increased with tested compounds relative to control.

Exceptional case is found with Ca (HpP04)2 which could att-

ributed to Co-immobilization and precipitation in the prese-

nce of either Ca or (H2P0 ) - . The amount of Co in the

roots was increased by the applied compounds with about 6,3,

2,1.5,1.5, 1 times relative to the control. The order was:

Fe-EDDHA> Fe (C00)2> Fe-DTPA> Al(0H)3 > F e ^ > Fe-OAC

Generally, more than 70% of Co was accumulated in the

roots except for Fe-DTPA (29%). This indicates that Co be-

haves as immobile element in plants. Although the complexa-

tion of Co as a transition cation with soluble organic ligands

can increase Co mobility both in soil and plant , the stability

of such ligands in soil will effect the metal mobility and

availability. As an example, a dramatic increase in mobility

of Co from shallow land burial waste sites at Oak ridge,

Tenn. was observed (5). The mobility was attributed to

- 6 -

the presence of EDTA and may be fulvic and humic acids. It

has been Co mobility decreased with time in the presence

of EDTA (6,7) this was attributed to the- breakdown of the

EDTA-Co complex with time and the high aricorption affinity

of the free Co.

4 . 3 . JLfJ..ei?JLJ?JL.^Uptake.

Cesium-134 uptake by clover decreased in all cuts com-

pared to control Tab. (1 and 3). It has been mentioned that

Cs adsorption decreases in the presence of increasing con-

centration of competing cations, which correlates with cation

exchange capacity and soil surface area (8,9).

134

Concerning the accumulation of Cs in roots as affect-

ed by the tested compounds, a reduction in the accumulated

Cs in the roots was observed in all tested compounds compar-

ed to control. It is worth mentioning that the opposite was

true in the case of Co experiment.

Cobalt ano other transition metals, shows only a slight

reduction in adsorbtion with increasing ionic strength and

competing cations composition even at concentration hgih

enough to be considered as brines or bitterns (10-11).

Also, desorption experiments show that a significant propor-

tion of these radionuclides do not exchange reversibly (12).

- 7 -

4.4. pobajj^ajr^ C ^

The Co and Cs accumulation parameters A and B of clover

plant were calculated from each set of data Tab. 2. The

applied compounds showed varied effects on the accumulation

parameters. The highest values were obtained in case of

FeDTPA and Fe(C00)2 treatment for Co. However, with Cs

it was only with Fe-EDDHA.

4 .5 . Pjg.kjjlj__gj]j_jCj> A^jajU-ajpiljij:^^

In order to assess the difference in Co and Cs

uptake efficiency of clover among 7 treatments, the values

of the availability parameters (C and S) were calculated ;.

from the A and B values presented in Tab. 4% The difference

in Co and Cs availability among treatments was assessed on

the basis of control to treatment relationship (Eq.(III)

with respect to Co or Cs accumulation of clover plant with

time. As shown in Tab. 4, DTPA is a good decontarainant comp-

ound with respect to polluted soil with Co which confirm the2

previous observation in Fig.l. Since the R values of the

accumulation parameter for Cs were not significant the

obtained C and S parameter are not valuble.

- 8 -

4 . 6 . T J 2 J L J L L J J t £ ! L i > L j ^ ^ 9 S L £ £ f L SR el a t iv e_ J_raj^l^cj!LtjLoJli

Cobelt and Cs translocation from clover roots to shoots

relative to control (RTR) was calculated as shown in Figs.2.

and 3. Generally the values of RTR over one ; means increase

in translocation and the lower means decrease in the trans-

location only Fe-EDDHA and Al (OH), treatments enhanced Co134RTR with time. However, Fe-DTPA treatment enhanced Cs

RTR sharply until time of 90 days then a dramatic decrease

was occurred.

REFERENCES

(1) F.R. Livens, D.L. Rimmer, Soil Use and Management,

4:63-69 (1988).

(2) C.B. Amphlet, L.A. McDonald, 0. of Inorganic and Nuclear

Chemistry, 2:403-414 (1956).

(3) R.K. Schulz, Health Physics, 11:1317-1324

(4) D.C. Van Schouwerburg, International report of soil

and plant analysis. Laboratory of soil and fertilizer,

Agraic. Univ Wageningen Netherlands (1968).

(5) O.L.Means, O.A. Crerar, 3.0. Duguid, Science, 200:1447

1481, (1978).

(6) D.L. Swanson, Status report, PNL-4389, Pacific North-

west Lab.. Richland, Wash. (1982).

(7) T.L. Dones, G.W. Gee, D.L. Swanson, R.R.Kirkham, in

"waste management" edited by R.G. Post, Proc. of the

symposium on waste management at Tuscon Arizona, Feb.

28-Mar. 3, 1983 Univ. Arizona press, Tuscon. (1983).

(8) R.Routson, D.Serne, The PERCOL MODEL BNWL 1718, Battelle

Pacific North-west Lab.. Richland, Wash. (1972).

(9) G.W.Gee, Rai Dhanpat, R.D.Serne, SSSA special publica-

tion number 11, Soil Sci. Soc. of America. MW.(1983).

(10) P.W. Rhodes, Soil Sci. Soc. Am. Roc. 21:389-392.

(1957).

(11) D.W. Bensen, Review of soil chemistry research at Hanford

HW-67201. (1960).

(12) R.3. Serne, D.F. Relyea, PNL-3997, Pacific North-west

Lab., Richland, Wash. (1981.

- 10 -

Table. 1

The Effect of Organic and Inorganic Compounds

on Clover Cumulative Dry Mater Yield, and Cumulative

Co/or Cs Uptake

Treatment

control

Fe-EDDHA

Fe-DTPA

Fe-OAC

Fe-(COO)

Al (CH)

Ca(H2P04)2

Fe2°3

control

Fe-EDDHA

Fe-DTPA

Fe-OAC

Fe(C00)2

Al(0H)3

Ca(H2P04)2

Fe2°3

shoot

dry matterg/plant

10.66

8.41

10.58

12.47

8.59

7.56

11.68

10.31

11.20

13.41

9.91

12.82

9.61

8.53

8.49

9.86

uptakeug

11.26

17.82

83.75

10.52

13.10

19.45

18.84

17.94

185.66

114.73

122.60

158.83

127.95

168.70

142.43

131.19

root

dry matterg/plant

7.30

4.05

7.18

9.98

5.85

4.77

7.79

6.72

6.29

8.90

5.37

7.16

7.15

7.33

7.22

7.50

uptake.ug

60.20

208.00

95.00

82.38

135.00

46.00

53.00

79.70

84.10

43.30

36.35

50.20

59.30

60.80

53.20

58.95

- 11 -

Table 2.

The Effect of Organic and Inorganic Compounds

on Clover Yield Parameters,and Co/or Cs accumulation

Parameters

Treatment

control

Fe-EDDHA

Fe-DTPA

Fe-OAC

Fe(C00)2

Al(0H)2

Ca(H2P04)

Fe2°3

control

Fe-EDDHA

Fe-DTPA

Fe-OAC

Fe(C00)2

Al(0H)2

Ca(H2P04)

Fe 20 3

Cointercept slope R

A

-1.70

-2.95

-1.87

-2.57

-1.59

-1.49

-1.14

-1.60

4.53

3.40

5.99

4.07

5.;05

3.19

3.82

4.40

B

1.70

1.75

1.25

1.65

1.07

0.96

0.91

1.11

-1.17

-0.43

1.49

-0.99

-1.39

-0.31

-0.254

-1.01

0.996

0.969

0.861

0.980

0.983

0.723

0.897

0.977

Cs

intercept Slope R

A B

-1.63

-2.31

-1.50

-1.50

-0.94

-0.66

-0.28

-1.03

1.15

1.53

1.03

1.110,75

0.58

0.07

0.81

accumulation parameters -

0. ,717

0.485

0.964

0.721

0.913

Ns0.254

0.512

5.20

5.53

4.30

4.29

3.81

4.01

4.29

5.19

-0.44

-0.76

-0.06

-0.05

0.24

4.01

0.04

0.49

0.919

0.938

0.940

0.980

0.586

0.446

Ns0.962

0.573

0.613

Ns

Ns

Ns0.176

. Ns

0.691

- 12 -

Table. 3

The Effect of Organic and Inorganic

Compounds on uptake of Co Cs as Percent of Applied

Treatment

control

Fe-EDDHA

Fe-DTPA

Fe-OAC

Fe(C00)2

Al(0H)3

Ca(H2P04)2

Fe2°3

control

Fe-EDDHA

Fe-DTPA

Fe-OAC

Fe(C00)2

Al(0H->3

Ca(HnPOA)

First cut

0.12

0.04

0.74

0.06

0.13

0.08

0.22

0.17

0.78

0.41

0.34

0.51 .

0.50

0.75

0.75

Activity

shoot

second cut

0.20

0.25

2.75

0.19

0.18

0.14

0.130

0.26

2.92

1.56

2.36

4.09

1.27

1.24

0 62

third cut.

0.34

0.80

1.510.61

0.30

0.48

0.72

0.63

4.79

4.16

2.75

3.14

2.84

3.42

2.47

root

7.51

3.50

11.58

13.98

13.48

2.94

7.06

9.09

5.46

3.97

2.01

3.71

4.38

4.65

3.96

0.75 1.68 2.16 4.56

- 13 -

Table 4.

The Effect of Organic and Inorganic

Compounds on Co/or Cs Availabiility parameters

Treatment

Pe

Pe

Pe

Pe

EDDHA

DTPA

OAC

(coo)2A1(OH)3

Cn<

Pe,:V°/}2>°3

CO.intercept

C

2

3

0

1.

0

0

0

220

817

35

115

124

359

/56

Csslope intercept slope

s C Savailability parameters

-0.17

3 82

-0.12

-0.16

-0.22

-0.13

-0.10

0 658

0.117

0.100

1.972

-1.300

-0.102

9-690

-0

-0

-0

-2

-1

0.

3-

157

454

.465

.203

.522

595

807

- 14 -

1.2

1.1

u.o

Fig. O~> Effect of treatmentdry rlf!>rt.

O S

r*::::

I//J

'/A

xmTr»wt.BB«it mttr r.nntrni

£22 CS-T

\//\Y/A,y/A//1f/A</A\S/ i

U/Y^A

yy/KxAVA$C*

r/A&\^C/*&>*

y/A

i ; : r«:

15 -

rstlo of Co/or C* content

soilTtealsaai ov«i austral.

Ci~treAC.«d so i l

- 16 -

Fig. QT) Extent of decontamination of Co-60 poiluted sol I

i*j

\

FP2O3

- 17 -

Fig. C3j Ef fect of LveaLtiicnts on Cs- 134 FiTR,

38

o FsKBDBAA faaaayt x