The assessment of mitotic and nuclear division indexes as biomarkers for estimating the risk on the health of residents exposed to the high natural radiation of Mamuju, West Sulawesi

Abstract

Cell proliferation is a potential biomarker and closely associated with the assessment of general cytotoxicity of chemical and physical agents under study. However, the utilization of these biomarkers in response to environmental stimuli such as natural radiation has not been adequately explored. This research aimed to assess the mitotic index (MI) and nuclear division index (NDI) in lymphocytes as biomarkers for predicting the risks on the health of residents living in high natural radiation area (HNRA) in Salletto and Ahu villages of Mamuju as a studied group. As a control group, people living in another region of Topoyo village were also studied. The observation of these both parameters was done according to the standard protocol as described by the International Atomic Energy Agency (IAEA). The result showed that the percentage of MI of lymphocytes obtained from the studied area was lower compared to those of the control area (6.48 vs. 9.41) whereas the percentage of NDI of lymphocytes obtained from the studied area was higher compared to those of control area (1.59 vs. 1.32). This finding is similar to previous studies in an adjacent area. The NDI obtained from manual counting was much lower than that obtained from the automatic machine for counting (1.59 vs. 22.46), of which it is due mainly to a factor in criteria for counting the cells. MI for the female is lower than that of male and there is a trend of decreasing mitotic index with increasing age in the same group. It is concluded that natural radiation exposure did not affect the proliferation of cells of local people which suggests a low risk of radiation-exposed related to inflammation.