ABSTRACT
The presence of structural chromosome aberrations and sister chromatid exchange frequencies (SCE) were studied in lymphocytes from 28 male subjects occupationally exposed to vinyl chloride monomer for a period of 9 years. A significant increase in chromosomal damages and elevated SCE frequencies was detected during the third and fourth year of the follow-up study. During the last 2 years, all examined parameters are approaching control values. This is a result of decreasing vinyl chloride monomer concentrations in the working environment without interrupting the working process.
Subject(s)
Occupational Diseases/chemically induced , Vinyl Chloride/toxicity , Adult , Aged , Chromosome Aberrations , DNA Damage , Follow-Up Studies , Humans , Male , Middle Aged , Sister Chromatid Exchange , Time FactorsABSTRACT
The distribution of vinyl chloride monomer (VCM)-induced chromosome breaks was studied in cultured lymphocytes of subjects occupationally exposed to this gas. In the examined subjects, the mean group value of chromosome aberrations is 6.5% and for sister chromatid exchange (SCE) frequencies, the mean value per cell is 7.9. These values are significantly higher than in the control population. Occupational exposure to VCM caused lymphocytosis together with disturbances of mitogenic activity in lymphocytes stimulated by phytohaemagglutinin. The results of G-banding showed that sites of chromosome breakpoints caused by VCM can be related to the lymphatic tissue disorders.
Subject(s)
Chromosome Aberrations , Lymphocytes/cytology , Occupational Exposure , Vinyl Chloride/adverse effects , Adult , Blood Cell Count , Cells, Cultured , Chemical Industry , Chromatography, Gas , Environmental Monitoring , Humans , Lymphocytes/metabolism , Male , Middle Aged , Mitosis , Sister Chromatid Exchange , Vinyl Chloride/metabolismABSTRACT
The micronucleus assay was performed in the peripheral lymphocytes of 32 subjects occupationally exposed to vinyl chloride monomer (VCM) divided into two groups according to years of employment. Blood samples were taken in the period from 24 h to 90 days following a transitory exposure to elevated VCM concentrations of 300 ppm due to the technological process. In subjects with a longer period of employment micronucleus frequencies decreased in proportion to the length of the interval after the last exposure to VCM. The results confirm that the micronucleus assay can serve as a suitable indicator of the time elapsed after last exposure to elevated concentrations of environmental mutagen. It can be assumed that duration of employment may contribute to the occurrence of the cumulative effect produced by exposure to elevated VCM concentrations.
