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ISSN 1028-334X, Doklady Earth Sciences, 2009, Vol. 427A, No. 6, pp. 1006–1011. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © G.G. Matishov, D.G. Matishov, D. Solatie, N.E. Kasatkina, A. Leppanen, 2009, published in Doklady Akademii Nauk, 2009, Vol. 427, No. 4, pp. 539–544.
The phenomenon of artificial radioactivity has been
observed for the natural environment since the first
nuclear tests in 1940s and continues at present. The dis-
posal and dumping of both solid and liquid nuclear
waste were typical for the Arctic and the northern seas.
Radiological hazard sites can be observed in the coastal
area, which are concentrated in Kola and Motovsky
bays; the city of Murmansk, as well as towns: Severo-
morsk, Polyarny, and Gadzhievo; and the following
inlets: Saida, Olenya, Pala, Zapadnaya Litsa, Ura, and
Ara. Gaseous, liquid, and solid nuclear wastes are
formed there. The European radiochemical factories
are the most significant producers of nuclear waste in
the Arctic Ocean. The Sellafield factory (Great Britain)
is the biggest one amongst them, which produced a
summarized waste of 160 ·
10
15
Bq. About 30% of
90
Sr
and from 10 to 20% of
137
Cs produced in Sellafield is
dumped in the Barents Sea. The western European
plume crosses the shelf area of the Barents Sea and
reaches the center of the Arctic Ocean within six years
[1–3]. The Chernobyl plume provided from 10 to 20%
of the nuclear pollution in the Kara and Barents seas in
the 1990s.
The radioactive level intensity has decreased an
order of magnitude in the Arctic marine ecosystems
from the 1960s to the 1990s as a result of water self-
clarification, natural decay of
90
Sr and
137
Cs, and the
reduction of nuclear waste dumping. Meantime, the
observations on the anthropogenic isotope dynamics
seem reasonable for the last decade taking into account
the time the passed after the Chernobyl core breakdown
and cessation of nuclear weapons tests on Novaya Zem-
lya and the adjacent shelf. The radiological hazard
problems, the environmental rate settings, and predic-
tive modeling of the long-term effect of low doses on
the marine biota are of current interest. The predictive
modeling of radiological hazards is necessary if atomic
power plants will be used on petroleum producing
areas, including the Shtokman oil–gas condensate field.
Monitoring of the accumulation of the artificial iso-
topes in the West Arctic environment and inhabitants
has been done by Murmansk Marine Biological Insti-
tute since 1990 [3–10]. The investigations were held in
cooperation with the Radiation and Nuclear Safety
Authority, STUK (Finland) in 1992–1999 and in 2006–
2007.
The current studies were performed during the
cruise of R/V
Dalnie Zelentsy
, August 18–September 8,
2008, in the Barents Sea. Twenty-four samples of sedi-
ments and sixteen water samples were taken to study
the present-day status of the environmental radioactive
contamination. Fourteen samples of the macroalgae
were taken in 2007 along the Barents Sea coast. Pre-
concentration of cesium isotopes from the water sam-
ples (100 l volume each) were performed by the cellu-
lose-inorganic sorbent
ANFEZH
(US Patent 5,407,889
from 18.04.95). The measurements of
137
Cs,
40
K, and
226
Ra activity was performed by the gamma-spectrom-
eter facility
Canberra
. An oxalate-radiochemical prep-
aration was applied before the measurements of the
specific activity of
90
Sr. The samples were then exposed
Natural Decrease of the Intensity Level of Artificial
Radioactive Isotopes in the Barents Sea
G. G. Matishov
a
, D. G. Matishov
a
, D. Solatie
b
, N. E. Kasatkina
a
, and A. Leppanen
b
Received October 21, 2008
Abstract
—The results of radioecological investigations carried out within the framework of the Russian–Finn-
ish high-latitude expedition in 2007 are presented. The characteristics of the present-day accumulation level of
the significant radioecological isotopes
137
Cs,
90
Sr and
239,240
Pu in the Barents Sea are described. The compar-
ative analysis is performed for the radiation pollution of the environment in the 1980s and 1990s and in the first
decade of the 21st century. Natural purification processes in the marine environment are the main factors of the
decrease in the intensity level of artificial radioactive isotopes. These processes include repeated dilution,
nuclear decay, occlusion by sediments and suspended solid material, and accumulation by aquatic inhabitants.
A stable decreasing trend is observed for the intensity level of artificial radioactive isotopes in the Barents Sea.
DOI:
10.1134/S1028334X09060269
a
Murmansk Marine Biological Institute, Kola Scientific
Center, Russian Academy of Sciences, Murmansk, Russia
b
Radiation and Nuclear Safety Authority, STUK, Regional
Laboratory of the Northern Finland, Rovaniemi, Finland;
e-mail: matishov@mmbi.info
OCEANOLOGY