Monitoring of natural radionuclides in water samples from LASU aquaculture and water plant

The purpose of this study is to measure and evaluate the radionuclide concentration in fifteen samples of water factory and fishery farm the water treatment facilities and fishponds at Lagos State University's Ojo Campus. After being placed in sterile 75 cl containers, these samples were brought to the lab for gamma spectroscopy-based radionuclide analysis. The activity concentration of potassium-40 (⁴⁰K), radium-226 (²²⁶Ra), and thorium-232 (²³²Th) ranged from 0.027 Bq/mL to 0.141 Bq/mL, 0.021Bq/mL to 0.082 Bq/mL and 0.021Bq/mL to 0.105 Bq/mL, with average value of 0.068 Bq/mL, 0.039 Bq/mL and 0.089 Bq/mL, respectively. All these values were found to be well below the maximum contaminant level (MCL) of 0.56 Bq/L for alpha emitters like ²³²Th and the Environmental Protection Agency's (EPA) safety threshold of 4 millisieverts (mSv) per year for beta and photon emitters, including ⁴⁰K. This suggests that the fish population is not at risk from radioactivity in the water. Additionally, in order to assess any possible health risks related to consumption, the total annual effective dose from the samples was also estimated, and found to range from 4.08 to 15.67 μSv/year with mean value 9.4 ± 3 μSv/year, that falls within the recommended the World Health Organization's (WHO) recommended limit of 0.1 mSv/year (100 μSv/year) for radionuclide ingestion from drinking water.