Occurrence and remediation of naturally occurring radioactive materials in Nigeria: a review

Abstract

Radioactive compounds are released in the environment by several anthropogenic activities, however, studies reveal that naturally occurring radioactive materials are responsible for over 80% of human exposure to ionizing radiation. Reports suggest that there are severe health risks associated with exposure to elevated concentrations of radioactive materials, such as potassium ( 40 K), uranium ( 238 U and 235 U), and thorium ( 232 Th). The rarity of comprehensive reviews addressing the occurrence, risk assessment, and potential remediation strategies of radioactive pollution in Nigerian environments propelled the collection of data over the last decade. Concentration as high as 2.42 ± 0.28 Bq/L has been reported in rivers in Nigeria, much higher than the radionuclide permissible level of 1 Bq/L. There are emerging concerns as activity concentrations of gamma-emitting radioactive materials found in soils are higher than worldwide average crustal values based on several reports. In many cases, the absorbed air dose rates were also greater (i.e., 86.44 nGy hr -1 ) than acceptable limits (60 nGy hr -1 ) except for few study areas. The level of radionuclides reported is indicative of the type of parent rocks and mineral composition of the studied area. Advances in remediation technologies suggest that electroremediation, bioremediation, and adsorption are the most efficient remedial approach for decontamination of radiochemical polluted sites. There is a need to explore an integrated synergistic approach for sustainable remediation of heavily polluted sites and in the light of environmental protection, attention must be given to areas with high levels of radioactive pollution. This review seeks to bridge information gaps towards ensuring that radioactive materials do not destroy our ecosystem.

Biosynthesized Metallic Nanoarchitecture for Photocatalytic Degradation of Emerging Organochlorine and Organophosphate Pollutants: A Review

“…Organochlorine insecticides volatilize from the soil upon application, becoming suspended in the air and then returning to the soil. Additionally, they might be absorbed by plants or seep into the earth, contaminating groundwater [60] . Antioxidant enzymes and non‐specific antioxidants are in charge of preserving the dynamic equilibrium between antioxidant reactions and oxidation products under normal physiological settings.…”

“…Additionally, they might be absorbed by plants or seep into the earth, contaminating groundwater. [60] Antioxidant enzymes and non-specific antioxidants are in charge of preserving the dynamic equilibrium between antioxidant reactions and oxidation products under normal physiological settings. When an organism's dynamic equilibrium between oxidation products and antioxidant responses is upset, oxidative stress results.…”

A Review on Bioremediation - An Emerging Technology for Treatment of Radionuclide Waste

“…Both natural and anthropogenic sources originate radiation in the environment. It is estimated that more than 80% of the worldwide environmental radiation is from natural sources [3] . Naturally occurring radionuclide can be grouped into three types viz.…”

Distribution dynamics and descriptive statistical analysis of radionuclides in the farmland soils near mining areas in Southwestern Nigeria

“…The two main methods of exposure to radionuclides are external exposure from radionuclides in soils and internal exposure from eating plants grown in such farmland soil and/or inadvertent ingestion during cultivation of the farmland soil (UNSCEAR, 2008; Kakati et al, 2013;Kpeglo et al 2011;Özdiş et al, 2017;Olatunji et al, 2022). The safety of lives against potential hazards ensuing from exposure to the radionuclides requires proper understanding of their concentrations, migration within the soil and in uential knowledge of factors responsible for the entire dynamics within the soil (Adebiyi et al, 2021;Geras'kin, 2016). Uranium, thorium, and their progenies are the most common natural radionuclides and are the main sources of radiation exposure for humans.…”