Ribosomal gene activity in lymphocytes of female workers exposed to aromatic hydrocarbons in the ceramics industry

Abstract

The ribosomal gene activity of peripheral blood lymphocytes was studied in a group of 27 females working in seven small pottery industries exposed to a mixture of aromatic hydrocarbons (AH) (xylene, toluene, trimethylbenzene isomers; tricloroethylene). All were relatively young and healthy women who have worked in this sector for an average of 9 years. The control group consisted of a sample of 27 women not employed in the ceramics industry matched for age ( +/- 2 years) residence and parity ( +/- 1). Lymphocyte cultures and chromosome preparations were set up by standard methods. Slides were silver stained and ribosome gene activity was evaluated in terms of the number of silver positive NORs (nucleolus organizing regions) per cell in 100 cells per subject by an observer who operated blind in the microscope. The difference in the mean number of NORs of the exposed group ( x = 8.00) compared to the control group ( x = 7.98) was not statistically significant. A multivariate analysis of the data was undertaken to study other possible characteristics of the subjects such as age, cigarette smoking, duration of exposure to AH, and work site. None of these variables contributed significantly to the variance in the values of ribosomal gene activity.