The Baltic Sea fish are becoming less contaminated with lead and PCB’s

Concentrations of lead and PCB’s in Baltic Sea fish have shown significant declining trends during the last 20-25 years, according to the Helsinki Commission’s study. 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 PCB’s to the environment.

The comprehensive monitoring programme coordinated by HELCOM allows for the assessment of 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.

As a result, annual emissions of heavy metals to the air have significantly decreased since 1990 and consequently their annual deposition onto the Baltic Sea has also halved since 1990.

According to the study, lead concentrations in liver tissues of various fish commonly consumed by humans (such as herring, cod, and perch) show coherent trends of similar magnitudes in various regions of the Baltic Sea. Since 1981 the concentrations of lead in herring and cod liver have been decreasing at an average rate of 4 - 7 % per year; and more recently in perch liver up to a rate of 13%.

The Helsinki Commission has imposed special bans and restrictions on the production and marketing of PCB’s since the 1980’s and called for measures to decontaminate PCB containing equipment and dispose of PCB’s in an environmentally sound manner with the final aim to completely cease the inputs of these hazardous substances to the Baltic Sea by the year 2020. As a result, PCB concentrations in herring muscle have shown significant decreasing trends during the last 25 years. The rates have varied between 4 and 10 % per year, implying a total decrease of 60-80% since the end of the 1970’s. PCB concentrations in cod and perch have also been decreasing with an average annual rate of decrease of 6–10% since 1980.

However, despite obvious progress in the reduction of discharges of lead and PCB’s 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 PCB’s and lead are significantly (3-6 times) higher in the Baltic Proper and in the southern Bothnian Sea even compared to the Kattegatt and the Skagerrak areas.

Follow up:
Lead concentrations in fish liver: http://helcom.navigo.fi/environment2/ifs/ifs2004/en_GB/lead/ 
PCB concentrations in fish muscle: http://helcom.navigo.fi/environment2/ifs/ifs2004/en_GB/pcbfish/

Contacts

HELCOM Secretariat

Mr Juha-Markku Leppänen
Professional Secretary
Tel: +358 9 62202227
Fax: +358 9 6220 2239

Mr Nikolay Vlasov
Information Secretary
Tel: +358 9 6220 2235