Rapp. Comm. int. Mer Médit., 36,2001
132
The natural radionuclide
210
Po is the main contributor to the radiation
dose received by humans from seafood consumption.
210
Po and
210
Pb con-
centrations can be locally enhanced by effluents of non-nuclear contami-
nation (use of artificial fertilizer, pesticide, detergent and fossil fuel)
adding potential risks for human health. The levels of naturally-occurring
210
Po and
210
Pb radionuclides in water, biota and sediment samples from
theTurkish marine environment have not yet been published in the scien-
tific literature. However, the
210
Po concentrations in biota and sediment
samples of Turkish sector of the Black Sea are given as ranges (1). On the
other hand, there are many papers published on the anthropogenic radionu-
clides especially
137
Cs concentrations in Turkish marine environment after
the Chernobyl accident (2-4). This paper reports the results of
210
Po and
210
Pb concentrations in macroalgae, sea snail, mussel and fish species col-
lected from the Turkish coast of the Black Sea and Marmara Sea stations
during the period 1997-2000.
Material and methods
The macroalgae species were: brown; C
y
s
t
o
s
e
i
ra barbata, and green;
Ulva lactucaand E
n
t
e
romorpha linza. The algae samples were washed in
distilled water to remove sand and other contaminating materials. T
h
ey
were then dried at 85°C to constant weight and homogenized. Similar sized
sea snail (Rapana venosa), mussel (Mytillus galloprov
i
n
c
i
a
l
i
s) and fis
h
species (shad, Aloso bu
l
g
a
r
i
c
a; anchov
y,E
n
g
raulis encra
s
i
o
c
o
l
u
s; bass,
D
i
c
e
n
t
ra
rchus labra
x; whiting, Merlangius euxinus; Picarel, S
p
i
c
a
ra maena
m
a
e
n
a; horse mackerel, Tra
churus tra
ch
u
r
u
s; red mullet, Mullus barbatus;
and bonito, S
a
rda sard
a) were stored in an insulated ice box with a plastic
bag and transferred to the laboratory. The samples were homogenized and
analyses were made on wet tissues or of total soft parts of the samples.The
measurements of
2
1
0
Po and
2
1
0
Pb were made using a standard method. T
h
e
concentration of
2
1
0
Po in wet or dry samples were performed starting with
a standard addition of a known activity of
2
0
9
Po as isotopic tracer. Samples
were completely dissolved with mineral acids (HNO
3
, HCl, H
2
O
2
). A
f
t
e
r
evaporation, polonium was plated onto silver disc in 0.5 M HCl in presence
of ascorbic acid. The silver discs were counted by silicon surface barrier
detectors (Model BU-019-300-AS) connected to a PC. After the first depo-
sition of
2
1
0
Po, the 0.5 M HCl was kept for five months to allow
2
1
0
Po in-
g
r
owth from the
2
1
0
Pb contained in the solution.
Results and discussion
2
1
0
Po activity levels in brown algae are higher than those found in green
a
l
gae species collected from Igneada, Kilyos, Amasra and Sinop stations
(
Table. 1). How
eve
r, the
2
1
0
Po concentration in green algae is higher than
b
r
own algae at M.Eregli station. In the algae species tested, the highest con-
centration of
2
1
0
Po was detected at the Amasra station.
2
1
0
Pb concentrations
in algae samples ranged between 0.51±0.33 and 17.47±1.23 Bq kg
-
1
.T
h
e
highest concentration of
2
1
0
Pb was found in brown algae from the Igneada
station. The
2
1
0
Po and
2
1
0
Pb concentrations in sea snail and mussel samples
are given in Table 2. The results showed that the
2
1
0
Po concentration in soft
parts of sea snail and mussel samples were the ranges 20.54±1.19 -
37.47±2.04 and 14.93±1.16 – 14.93±1.16 Bq kg
-
1
wet weight, respective
l
y.
H
ow
eve
r, the
2
1
0
Po levels in muscle tissue of the sea snails were detected to
be about 1 Bq kg
-
1
wet weight. The highest
2
1
0
Pb concentrations in sea snail
soft parts and mussel samples were found to be 5.24±0.39 and 4.62±0.26 Bg
k
g
-
1
at Persembe and Rize stations, respective
l
y.The
2
1
0
Po and
2
1
0
Pb con-
centrations in fish species are given in Table 3. The levels of
2
1
0
Po concen-
tration in anchovy were within the range of 27.5±1.2 and 53.4±1.7. T
h
e
2
1
0
Po activity in Marmara anchovy samples are significantly higher than that
in Black Sea fish.
2
1
0
Po concentrations in red mullet and bonito were found
to be 10.2±0.90 and 26.1±1.88 Bq kg
-
1
(wet weight), respective
l
y. On the
other hand, The
2
1
0
Po concentrations were lowest in shad, bass, whiting,
picarel and horse mackerel. Topcuoglu et al.(4) inve
s
t
i
gated the
1
3
7
Cs in
biota samples from the Turkish coast of the Black Sea and Marmara Sea dur-
ing the period of 1997-1998. In that study it was found that the
1
3
7
Cs activ-
ity in algae and in soft parts of sea snail and mussels were below the low
e
r
limit of detection. At the same time,
1
3
7
Cs concentrations in fish species
were found to be between <3 – 4.8 Bq kg
-
1
wet weight. These results con-
firm that the dominant contribution at the total radioactivity concentration in
biota samples comes from natural radionuclides.
Acknowledgement.Thanks are due to IAEA for supporting part of this study under
Contract No. 9712/R1/RO and Technical Cooperation Contract No RER/2/003 for
Technical Assistance. We also thank to I.Akkurt for his valuable assistance.
References
1.Topcuoglu S. 2000. Black Sea Ecology, Pollution Research in Turkey of the Marine
Environment,IAEA Bull. 42,4:12-14.
2.Topcuoglu S., Güngör N. 1999. Radionuclide concentration in macroalgae and sediment
samples from the Bosphorus. Turkish J. Mar. Sci.5:19-24.
3.Topcuoglu S., Güngör N., Kut D., Esen N., Egilli E., Kirbasoglu Ç., Güven K.C., Ünlü
S. 1998. Radioecological Research in Turkish Black Sea Marine. Environment. In:
Pro.First Int.Symp.On Fisheries and ecology, 2-4 Sept.Trabzon-Turkey, p.440-443.
4.Topcuoglu S., Kut D., Esen N.,Güngör N.,Ölmez (Egilli) E.,Kirbasoglu Ç.
137
Cs in
biota and sediment samples from Turkish coast of the Black Sea, 1997-1998.
J.Radioanal.Nucl.Chem.(in press).
210
PO AND
210
PB CONCENTRATIONS IN BIOTA FROM THE TURKISH COAST
OF THE BLACK SEA AND MARMARA SEA
N. Güngör*, S. Topcuoglu, Ç.Kirbasoglu
Çekmece Nuclear Research and Training Center, Istanbul, Turkey
Abstract
This paper reports concentrations of
210
Po and
210
Pb radionuclides from the Turkish marine environment during the period of 1997-2000.
According to the findings the natural radionuclide levels have increased in some Turkish biota samples. For this reason, besides assessing
anthropogenic radionuclides, efforts should concentrate on the natural radionuclides, especially
210
Po.
Key-words:Radioactivity,biota,Black Sea,Marmara Sea
StationCollectionSpecies
210
Po
210
Pb
date
Igneada
24.02.98C.barbata13.4±0.617.5±1.2
U.lactuca12.1±0.93.6±0.4
Kilyos
5.03.98C.barbata25.3±1.55.2±0.5
E.linza8.0±0.75.9±0.6
Amasra
11.11.97C.barbata54.7±2.611.6±0.8
U.lactuca42.3±1.611.3±0.6
Sinop
12.11.97C.barbata29.4±1.00.5±0.3
U.lactuca15.3±0.60.9±0.1
Persembe13.11.97C.barbata8.3±0.42.5±0.1
M.Eregli22.05.00C.barbata36.7±2.5NM
U.lactuca46.5±3.7NM
Table 1.
210
Po and
210
Pb concentrations (Bq kg
-1
in dry weight) in
macroalgae species
StationCollectionName and
210
Po
210
Pb
dateTissue
Sea snail
R.Feneri5.03.98Soft part22.6±1.2<0.2
Muscle0.9±0.2<0.2
Amasra
11.11.97Soft part20.5±1.20.8±0.2
Muscle0.9±0.11.7±1.1
Persembe13.11.97Soft part37.5±2.05.2±0.4
Muscle1.1±0.2<0.3
Rize
26.06.98Soft part20.8±0.52.3±0.1
Muscle0.9±0.10.3±0.1
Mussel
Igneada24.02.98Soft part18.1±1.1_
Kilyos
5.03.98
18.1±1.0_
R.Feneri5.03.98
14.9±1.2_
Amasra
11.11.98
18.4±0.73.7±0.5
Sinop
12.11.97
42.1±1.71.8±0.2
Rize
26.06.98
16.9±0.84.6±0.3
Sarköy
22.05.00
22.1±1.3NM
Table 2.
210
Po and
210
Pb concentrations(Bq kg
-1
in wet weight) in sea
snail and mussel species - NM, not measured
StationsCollectionName
210
Po
210
Pb
Date
Igneada24.02.98Shad fish1.4±0.1<0.1
Amasra
10.11.97Anchovy32.0±1.9_
Sinop
12.11.97Anchovy26.9±1.2_
Persembe13.11.97Anchovy27.5±1.2_
13.11.97Bass fish0.5±0.1<0.1
Rize
26.06.98Whiting fish1.0±0.1_
Ordu
17.03.99Anchovy46.3±3.42.2±0.1
17.03.99Whiting fish5.4±0.4<0.1
Tekirdag25.05.00Picarel fish2.6±0.5NM
25.05.00H. mackerel2.0±0.2NM
25.05.00Red mullet10.2±0.9NM
Marmara30.10.00Anchovy53.4±1.7NM
Ünye
30.10.00Bonito26.1±1.9NM
Table 3. 210Po and 210Pb concentrations (Bq kg-1 in wet weight)in fish
species
