Scientists' Contributions

Use of the algae as biomonitors of radioactive pollution

B. Veleva

National Institute of Meteorology and Hydrology, Sofia, Bulgaria

    The content of radionuclides in algae species and their use as biomonitors of the radioactive pollution have been studied for many years. In fact this approach is used mainly related to their natural environment, water. In some particular cases, primary in case of accidental release of radionuclides into the atmosphere and consequent deposition over the sea surface the knowledge of radioactive pollution in algae could give some additional information. After the Chernobyl accident the date for the short lived gamma emitting nuclides in the marine coastal environment is mainly from biota (including algae) samples. The main advantages of the algae in comparison to the direct surface water sampling are averaging over space and time in higher degree than discrete water sampling and easier sample pre-treatment, mainly because the algae species have been already pre-concentrated certain radionuclides. To evaluate the accidental impact preliminary information about the background concentrations is needed as well as development of the appropriate methodology for sampling and analytical procedures for radionuclides concentration determination. The preparedness to use algae as biomonitores in case of accidental releases in Bulgaria as well as in the other Black Sea countries has been sufficiently increased under the IAEA TCP RER/2/003.

    In the present report the range of concentrations of 137Cs, 90Sr and some actinides in brown and green algae species along the Bulgarian Black Sea coast is given. The methodology is briefly described. The results are discussed and compared to other Black Sea areas. The CF of Cystoseira and Ulva sp. for 137Cs is estimated based on the algae and water concentrations in the marine environment.