Natural radioactive risk assessment in top soil and possible health effect in Minim and Martap villages, Cameroon: using radioactive risk index and statistical analysis

Abstract

AbstractThe Minim and Martap villages are famous for their richness in bauxite mineralization. Acute respiratory infection, known to stem from 238U and 232Th activities, is one of the main reasons to the mortality and morbidity of the over 40,000 local inhabitants. Radioactive elements in top of the soils of the area are potential causes to this infection. Therefore, the natural activity concentration of radioactive elements in the area was investigated. Top soil samples collected from the village settlement area and some plateaus were analyzed using methods LF700 (for 40K) and LF100 (for 238U and 232Th). The measured concentration of the elements was higher than the world mean value. Samples of felsic volcanic soils and rocks were identified to have the highest concentration of the elements. 232Th and 238U revealed relatively higher activity concentration while that of 40K was lower. Absorbed dose rate are higher in all the samples by a factor range of 1.2–2.1 times greater when compared to world average. Annual effective indoor and outdoor doses, radi-um equivalence (Raeq), internal (Hin) and external (Hex) hazard indexes, and the Excess lifetime cancer risks of samples, are all within the world averages by UNSCEAR.