Cytogenetic effects of methyl isocyanate exposure in Bhopal.
Among human survivors following the methyl isocyanate (MIC) gas tragedy the major complaints have been related to deep-seated suffocation, terrible pain in breathing, and severe ocular irritations. In order to assess the possible genetic effects we have used lymphocyte cultures and screened chromosomes by two techniques; one by looking for chromosomal aberrations and the other by estimating sister-chromatid exchange (SCE) frequencies. Both these parameters are good indicators of genetic damage in chromosomal DNA. SCE frequencies in lymphocytes have been increased more than three times in MIC-exposed persons. The results were compared to two groups of controls (one group comprising persons present in the same house; the second group of persons were chosen from distant places, 20-50 km away from the incident). Chromosomal breaks have been observed in 10 out of 14 MIC-affected people (71.4%) studied while only 6 out of 28 (21.4%) controls had chromosomal breaks. Some MIC-exposed persons had chromatin bodies in addition to the normal 46 chromosomes. These observations suggest that chromosomal DNA has been damaged.
D000062:Accidents, Occupational; D002617:Chemical Industry; D002869:Chromosome Aberrations / Q000187:drug effects*; D003485:Cyanates / Q000506:poisoning*; D004190:Disasters; D006801:Humans; D007194:India; D017953:Isocyanates; D007621:Karyotyping; D008214:Lymphocytes / Q000648:ultrastructure; D012854:Sister Chromatid Exchange / Q000187:drug effects
D003485:Cyanates; D017953:Isocyanates; C008461:methyl isocyanate