Cytological effects of paper mills effluents on somatic cells of Allium cepa.

The cytological effects of paper mills effluents on somatic cells of Allium cepa were presented. The cytological effect decreased by decreasing the concentration of the effluents. Disturbed metaphase, anaphase and telophase, occurrence of binucleate and tetranucleate cells comprised the most dominant types of abnormalities. Clumping of chromosomes, contracted chromosomes, pleiomorphic and micronuclei formation, cell vacuolation and polyploid cells are found less frequently. The c-mitotic effect and other abnormalities may be due to the action of alkalies, acids and bleaching agents present in the paper mill effluents.