Assessment of Polonium-210 concentration and annual committed effective dose in edible muscle tissue of blue swimmer crab (portunus armatus), prawn (Penaeus monodon), shrimp (farfantepenaeus notialis), and crayfish (procambarus clarkii) from the deep sea of Sangana, Niger Delta, Nigeria
摘要
This study investigated the activity concentration of Polonium-210 (210Po) in the edible tissues of Portunus armatus (blue swimmer crab), Penaeus monodon (prawn), Farfantepenaeus notialis (shrimp), and Procambarus clarkii (crayfish) harvested from the deep sea of Sangana. Twelve specimens were harvested directly from artisanal fishers using traditional fishing gear to ensure ecological representativeness of the local catch. To strengthen methodological transparency and reduce variability, three individuals per species (n = 3) were randomly selected from the twelve collected specimens and shellfish samples were analyzed via alpha spectrometry techniques to determine 210Po levels. The results revealed precise numerical values of 210Po in the different shellfish, with concentrations of 34.15 Bq·kg⁻¹ fresh weight in crab, 43.19 Bq.kg−1 fresh weight in prawn, 49.57 Bq.kg−1 fresh weight in shrimp, and 35.37 Bq·kg⁻¹ Bq.kg−1 fresh weight in crayfish. This reveals a lower level of 210Po, which is below the internationally recommended limits of 1000 µSv.y−1 for shellfish consumption. The calculated annual effective doses were 545, 689, 791 and 565 µSv.y−1 respectively. This suggested low levels of exposure to shellfish consumers, with values below the recommended limit of 1000 µSv.y−1 set by the ICRP for the effective dose. Among the analyzed species, Farfantepenaeus notialis and Penaeus monodon demonstrated the highest annual committed effective dose (ACED) of Polonium-210 (²¹⁰Po). Despite this, the estimated radiological health risks for local populations that consume these shellfish as a dietary mainstay remain within the internationally recommended limit. The results obtained in this study were far below the limits. Regular monitoring should be encouraged for edible shellfish harvested from important fishing zone in the Niger Delta to ensure food safety.