COMMITTED EFFECTIVE DOSE FROM NATURAL RADIONUCLIDES IN FARM-RAISED AND WILD CATFISH IN IBADAN, NIGERIA

There is extensive contamination of the aquatic environment when rivers and streams flow through areas of high human activities such as industrial cities and major towns. These contaminations may include enhanced background levels of naturally occurring radioactive materials resulting from rapid urbanization and other human activities. The natural radionuclides (40K, 238U (226Ra) and 232Th (228Ra)) contents of farm-raised and wild catfish in five fish farms and three major rivers within Ibadan metropolis have been studied using gamma spectrometry. The results indicate that the average committed effective doses from the ingestion of the two sets of catfishes are 104 ± 37 and 104 ± 32 μSv/y for farm-raised and wild catfish, respectively. It can be concluded that the consumption of the catfishes poses no immediate radiological hazards to the population of the study area.