Spatial Distribution of Gamma Dose Rates in the Marine Environment of Unumherin Community in Niger Delta, South-South, Nigeria

This work investigates the radioactivity distribution of coastal polluted areas of Unumherin Community in Niger Delta, Nigeria. The measurement of the outdoor dose rate of the polluted coastlines was carried out using calibrated hand-held gamma detector, (RS-125 Gamma-Spec). The spatial distribution of gamma dose rate indicates the hotspot at location 4 with a value of 100 nGy/h. Maximum and minimum values of the absorbed dose-rate was observed in location 4 with the value of 100 nGyℎ−1 and location 15 with the value of 2 nGyℎ−1, respectively. This is an indicative that the risk of ionizing radiation exposures is much higher for location 4 than other locations. This higher value of 100 nGyℎ−1 is far more than the recommended limit of 59.00 and 84.00 nGyℎ−1 provided by UNSCEAR, 2000. The community requires much more radiological monitoring for the safety of human and ecosystem

Dispersion of gamma dose rates and natural radionuclides in the coastal environments of the Unumherin community in Niger Delta

The outdoor gamma dose rates and the activity concentrations of potassium-40, uranium-238, and thorium-232 within the study area were carried out using calibrated hand-held gamma detector (RS-125 gamma spectrometer) and NaI(Tl) gamma spectroscopy. The in-situ measurement results of the gamma dose rate indicate that the hotspot is at location 4 with a value of 100 nGyh-1. The results from the NaI(Tl) gamma detector revealed the highest activity concentrations of potassium-40, uranium-238, and thorium-232 to be 288.09, 96.49, and 136.12 Bqkg−1 for sediments and 257.31, 66.93, and 96.57 Bqkg for water, respectively. The highest mean activity concentration of potassium-40 and uranium-238 was observed in Catfish with values of 151.87 and 38.00 Bqkg−1, whereas the highest value for the activity of thorium-232 was observed in Tilo Fish with a value of 89.02 Bqkg-1. In comparison, all the observed values are higher than the populationweighted average of 420.00, 32.00, and 45.00 Bqkg−1 for potassium-40, uranium- 238, and thorium-232 according to UNSCEAR. Geologically, this may be attributed to the marine incursion of regional tectonic subsidence during transgression. Statistically, the correlation results confirmed that the enhanced outdoor dose rates at the coastline environment were caused mainly by uranium-238, followed by thorium-232 and then potassium-40 in magnitude. The mean hazard indices calculated for the samples were also observed to be within the global average values recommended by ICRP

Dispersion of gamma dose rates and natural radionuclides in the coastal environments of the Unumherin community in Niger Delta

AbstractThe outdoor gamma dose rates and the activity concentrations of potassium-40, uranium-238, and thorium-232 within the study area were carried out using calibrated hand-held gamma detector (RS-125 gamma spectrometer) and NaI(Tl) gamma spectroscopy. The in-situ measurement results of the gamma dose rate indicate that the hotspot is at location 4 with a value of 100 nGyh-1. The results from the NaI(Tl) gamma detector revealed the highest activity concentrations of potassium-40, uranium-238, and thorium-232 to be 288.09, 96.49, and 136.12 Bqkg−1 for sediments and 257.31, 66.93, and 96.57 Bqkg for water, respectively. The highest mean activity concentration of potassium-40 and uranium-238 was observed in Catfish with values of 151.87 and 38.00 Bqkg−1, whereas the highest value for the activity of thorium-232 was observed in Tilo Fish with a value of 89.02 Bqkg-1. In comparison, all the observed values are higher than the population-weighted average of 420.00, 32.00, and 45.00 Bqkg−1 for potassium-40, uranium-238, and thorium-232 according to UNSCEAR. Geologically, this may be attributed to the marine incursion of regional tectonic subsidence during transgression. Statistically, the correlation results confirmed that the enhanced outdoor dose rates at the coastline environment were caused mainly by uranium-238, followed by thorium-232 and then potassium-40 in magnitude. The mean hazard indices calculated for the samples were also observed to be within the global average values recommended by ICRP

Radioactivity distributions and biohazard assessment of coastal marine environments of niger-delta, Nigeria

ABSTRACTThe Unumherin community in Nigeria’s Niger Delta is home to coastal marine polluted zones, and this research examines the radioactivity distributions and biohazard in the coastal environment. The activity concentrations of 40K, 238U, 232Th, as well as the outdoor dose rate of contaminated coastlines were measured using a calibrated RS-125 Gamma-Spec and a NaI(Tl) gamma-detector. The laboratory examination of sediments, water, and fish from the same coastal region – Clarias gariepinus Pseudotropheus elongated Oreochromis niloticus and Stromateus fiatola – was combined with the in-situ observations of gamma dose rates. With a value of [Formula: see text], the hotspot at site 4 is shown by the geographic distribution of gamma dose rates. The findings showed that the activities of the primordial radionuclides varied, with average values for the sediments and water exceeding suggested limits. Similarly, the corresponding mean hazard indices mostly exceeds the allowable limits. The species specificity of the fish species accounts for the variation in the mean concentrations of 40K, 238U and 232Th. C. gariepinus, having accumulated higher concentrations of 40K and 238U, may be the first to elicit health hazards in the future if pollution continues unmonitored. Hence, continuous monitoring of the aquatic environment alongside is highly recommended