Adaptive responses on chromosome aberration and DNA breakage of peripheral lymphocytes from workers exposed to thorium and rare earth mixed dust in Baotou Steel Plant / 中华放射医学与防护杂志

Objective To explore if the occupational exposure to low dose thorium could induce adaptive response in peripheral lymphocytes.Methods 40 individuals.who exposed to thorium and rare earth mixed dust(exposure group) or control in Baotou Steel Plant, were selected, and chromosome aberrations were analyzed.Then the peripheral blood samples were irradiated in vitro with 2 Gy60Co γ-rays,and unstable chromosome aberration or DNA stand breakage analysis using single cell gel electrophoresis was performed. Results The dicentrics before 2 Gy exposure in exposure group was higher than that in control(P>0.05). But the dicentries after 2 Gy exposure in exposure group was lower than that in control,but not significantly (P>0.05).The tricentrics in exposure group was significantly lower than that in control(U=3.1622, 0.0ol<P<0.002).The DNA strand breakage in control group was significantly higher than that in exposure group(t=25,P<0.001).Conclusions Occupational exposure to low dose thorium could induce the adaptive response on chromosome aberration and DNA strand breakage in peripheral lymphocytes.

Study of chromosome aberrations OH the workers occupationally exposed to thorium and rare earth mixed dust / 中华放射医学与防护杂志

Objective To study the effect of thorium and rare earth mixed dust on chromosome aberrations in the lymphocytes of occupational exposed worker8.Methods Analyses of unstable chromosome aberrations on 53 occupational exposed worker8 and 58 control workers were carried out by the conventional Giemsa staining method.Fluorescence in situ hybridization method Wills performed to analyze the chromosome stable aberrations on 10 occupational exposed workers and 10 control workers.Results The frequencies of chromosomal aberration cells,dicentfics plus rings,total aberrations in exposed workers were significantly higher than those in controls.No significant difference was found in the frequency of acentric aberrations between exposed and non-exposed workers.No significant difference was found in the frequency of translocations between exposed and non-exposed workers.Conclusions Chronically occupational exposure to thorium and rare earthmixed dust can increase the induction of unstable chromosome aberration,but the increase of stable chromosome aberrations(translocation)can not be observed.