RESUMO
Objective:To investigate chromosomal aberrations in peripheral blood lymphocytes of underground miners, in order to explore the influencing factors involved in chromosomal aberration levels of non-uranium metal mines.Methods:Totall 135 workers were recruited from an iron mine and a gold mine located in different cities of Henan province, where 69 workers worked aboveground and 66 miners worked underground in the metal mines. The radon concentration in the mines was measured by solid-state nuclear track detectors. Chromosomal aberrations in peripheral blood lymphocytes from the subjects were detected using conventional analysis method, and the influence factors of chromosomal aberrations were analyzed.Results:Radon concentration was 30-2 943 Bq/m 3 in the aboveground workplace of the mines, and 62-28 314 Bq/m 3 in underground. The age of the underground group was obviously lower than that of the aboveground group( t=2.12, P<0.05), but the frequencies of dicentrics, translocation, acentric fragment, and total chromosome-type aberrations in the underground group were significantly higher than those in the aboveground group ( χ2=10.49, 16.74, 8.15, 29.50, P<0.01). Consistent results were obtained when only male workers were regarded as object of observation ( χ2=8.44, 11.63, 4.94, 20.81, P<0.05). The frequency of translocation ( χ2=8.44, P<0.05) was dependent on the length of service in the underground group. Poisson regression analysis indicated that the aboveground and undergroud grouping partly affected the levels of dicentrics, translocation, acentric fragment, and total chromosome-type aberrations (the underground group IRR=3.25, 2.69, 1.97, 2.18, P<0.05). Conclusions:The radon exposure in the underground workplace of the metal mines may be the main factor resulting in the increase of chromosome-type aberrations of miners. The occupational health and safety of the miners who may be exposed to high radon levels are worthy of great attention.
RESUMO
Objective@#To investigate the effects on human peripheral blood erythrocytes of long-term occupational contact with chromate.@*Methods@#A dynamic cohort study was conducted of chromate-exposed workers (343 cases) and non-chromate-exposed workers (73 cases) at a chromate production enterprise who were selected according to specific inclusion and exclusion criteria from 2010 to 2015. Personal information and chromate exposure information were obtained by questionnaire. A generalized estimating equation was employed to analyze the effects on human peripheral blood erythrocytes of long-term occupational contact with chromate, controlling for age, gender, smoking, alcohol consumption and body mass index.@*Results@#The mean ages and working ages of those entering the cohort study were 36.67 ±6.78 and 38.47 ± 7.18, respectively, for the exposure group and 8.39 ± 6.02 and 12.86 ± 8.34, respectively, for the control group. The erythrocyte content [(4.73±0.46), (4.81±0.53), (4.41±0.45)]×1012/L in the peripheral blood in the chromate exposure group was lower than that [(4.76±0.42), (4.95±0.45), (4.47±0.39)]×1012/L in the control group for the years 2010, 2011, 2012 and 2014 (t values were 0.38, 1.96, 0.92 and 1.21; P values were 0.703, 0.051, 0.358 and 0.227, respectively). The correlations between the years 2010 and 2011, 2011 and 2012, 2012 and 2014, and 2014 and 2015 were 0.667, 0.464,-0.070 and 0.020, respectively (P<0.001). The RR for males and those that consumed alcohol were 0.661 (95% CI: 0.616-0.709) and 0.910 (95% CI: 0.811- 1.201), respectively. Compared with the control group, the risk of reduced erythrocyte levels in the peripheral blood was increased by 0.915 (95% CI: 0.852- 0.982) in the chromate-exposed group.@*Conclusions@#The erythrocyte content of peripheral blood was reduced after long-term exposure to chromate. Maleness and alcohol consumption were factors that increased the risk of reduced peripheral blood erythrocytes in the chromate-exposed population.