A comparative cytogenetic study on cases of induced abortions in TCDD-exposed and nonexposed women.

In order to evaluate the cytogenetic findings previously obtained on induced abortions in women exposed to 2,3,7,8 tetrachlorodibenzo-p-Dioxim (TCDD) after the Seveso accident, chromosome analyses were carried out on a comparable control sample. The frequencies of aberrant cells, the relative proportions of individual types of chromosome aberration, the average number of lesions per damaged cell, and the frequencies of polyploids do not differ significantly in maternal blood and placenta in the two samples. A highly significant increase in the frequencies of aberrant cells and in the average number of aberrations per damaged cell was found in the fetal tissues in the group of exposed pregnancies. A noticeable feature of the data on the frequencies of cells with aberrations is the marked variability among individuals within tissues and within samples. On the basis of these results, the authors point to the need to continue cytogenetic investigations on interrupted pregnancies in TCDD-exposed and nonexposed women.