Soil radioactivity and incidence of cancer in Nigeria.

The significance of exposure from natural radioactivity in soil and the potential risk for causing health detriment have not received adequate attention in Nigeria. Cancer has become a major cause of mortality in the recent times and now the public interest in the long-term effects of radiation on humans has assumed great prominence following the establishment of a nuclear regulatory body in Nigeria. This study is an effort to investigate a possible relationship between reported cancer incidence and external terrestrial radiation dose level across the six geo-political zones of the country. Data from the national cancer registries across the zones were compared with expected cancer incidences due to soil radioactivity based on the linear no-threshold model (LNT). A regression equation that best describe the reported cancer incidence and the expected cancer incidence was developed. It was observed that cancer cases attributable to radiation exposure due to soil radioactivity is low, constituting only between 1.3% and 9.2% of the total reported cases.