HELSINKI, Finland, January
4, 2005 (ENS): There is good news for people who eat fish
from the Baltic Sea - they are less contaminated now than they were
25 years ago. Concentrations of lead and polychlorinated biphenyls
(PCBs) in Baltic Sea fish have declined during the last 25 years,
according to a new study issued Monday by the Helsinki Commission.
The Helsinki Commission, or HELCOM, works to protect the marine
environment of the Baltic Sea from all sources of pollution through
intergovernmental co-operation between the countries bordering the
sea - Denmark, Estonia, the European Community, Finland, Germany,
Latvia, Lithuania, Poland, Russia and Sweden.
HELCOM is the governing body of the "Convention on the Protection
of the Marine Environment of the Baltic Sea Area," more usually
known as the Helsinki Convention.
The decrease of contaminants in the Baltic Sea fish is a result
of measures taken by the HELCOM countries to reduce discharges of
lead and PCBs to the environment, the Commission said when launching
The Baltic Sea, as one of the world’s largest bodies of brackish
water, is ecologically unique. Due to its special geographical,
climatological, and oceanographic characteristics, the Baltic Sea
is highly sensitive to the environmental impacts of human activities
in its catchment area, which is about four times larger than the
sea area itself and is inhabtied by some 85 million people.
The comprehensive monitoring program coordinated by HELCOM assesses
the whole pathway of hazardous substances - from emissions on land
to their effects in the marine environment, including fish.
"This information allows for appropriate decisions to be made
in order to reduce pollution," the Commission said.
As a result, annual emissions of heavy metals to the air have decreased
since 1990 and consequently their annual deposition onto the Baltic
Sea has been halved during that time, HELCOM said.
The study found that lead concentrations in liver tissues of fish
commonly eaten by humans, such as herring, cod, and perch, show
"coherent trends of similar magnitudes in various regions of
the Baltic Sea."
Sampling, sample preparation, storage in specimen bank and evaluation
of results were carried out by the Contaminant Research Group at
the Swedish Museum of Natural History, Stockholm. Chemical analysis
was carried out at Institute of Applied Environmental Research at
They have documented that since 1981 the concentrations of lead
in herring and cod liver have been decreasing at an average rate
of four to seven percent per year, and more recently in perch liver
up to a rate of 13 percent.
The Helsinki Commission has imposed bans and restrictions on the
production and marketing of PCBs since the 1980s and called for
measures to decontaminate PCB containing equipment and dispose of
PCBs in an environmentally sound manner. The Commission's goal is
to completely cease the input of these hazardous substances to the
Baltic Sea by the year 2020.
As a result of these bans and restrictions, PCB concentrations
in herring muscle have shown significant decreasing trends during
the last 25 years. The rates of decrease have varied between four
and 10 percent a year, indicating a total decrease of 60 to 80 percent
since the end of the 1970s.
PCB concentrations in cod and perch also have been decreasing,
with an average annual rate of decrease of six to 10 percent since
Still, despite obvious progress in the reduction of discharges
of lead and PCBs to the environment, their concentrations in the
sea water are still several times higher in the Baltic Sea compared
to waters of the North Atlantic.
Concentrations of PCBs and lead are three to six times higher in
the Baltic Proper and in the southern Bothnian Sea even compared
to the Kattegatt and the Skagerrak areas, HELCOM said.
In general, the concentrations of heavy metals and organic pollutants
in sea water are several times higher in the Baltic Sea compared
to waters of the North Atlantic.
Continued eutrophication and persistent pollutants in living organisms
are the main concerns underlined in a set of new and updated HELCOM
environmental indicators launched by the Helsinki Commission Monitoring
and Assessment Group in December 2004.
The regional extent of eutrophication is clear from concentrations
of nutrients in winter and the subsequent intensity of spring phytoplankton
blooms. Toxic blooms of blue-green algae, or cyanobacteria, continue
to be extensive in the Baltic Sea, the monitoring group warned.
The amount of radioactive caesium-137 in the Baltic Sea from the
1986 Chernobyl explosion and fire remains unchanged, with highest
concentrations in the sediments of the Bothnian Sea and the Gulf
Even though an increase in maritime transportation across the Baltic
during the past decade has increased the potential for illegal oil
discharges, the number of observed illegal oil discharges has been
decreasing every year. Still, some 300 illegal oil spills were detected
The Baltic Sea catchment area extends over some 1.7 million square
kilometers and is home to nearly 85 million people.
There are 11 cities with populations greater than 500,000 citizens
in the catchment area, and almost 15 million people live within
10 kilometers of the coastline.
View the new Baltic Sea indicators online at: http://helcom.navigo.fi/environment/indicators2004/en_GB/indicators2004/
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