Mitotic disturbances induced by low doses of inorganic lead

Abstract

Adventitious roots of Allium cepa L. have been treated with the sublethal dose of 2.5 mg dm−3Pb2+as well as the partly lethal one—3.0 mg dm−3Pb2+derived from two lead compounds: PbCl2and Pb(NO3)2. These compounds induced numerous C-mitoses. This effect coincided with a strong inhibition of the root growth and lowering of the mitotic activity. However, lead effect in this range does not constitute a genetic threat in natural environment, since lead doses with such strong effects do not normally occur in the environment. However the lower lead dose, 1.0 dm−3Pb2+from PbCl2and Pb(NO3)2resulted in slight but statistically significant clastogenic effects, without disturbing the mitotic activity. It has further been found that lead chloride (the component of car exhaust gas) administered in the low dose (1 mg dm−3) was more clastogenic than lead nitrate. The presented results point to a potentially mutagenic effect of low lead doses. © 1988 by the Japan Society for Bioscience, Biotechnology, and Agrochemistry.