Mitotic Disturbances Induced by Low Doses of Inorganic Lead

Abstract

SUMMARY -Adventitious roots of Allium cepa L. have been treated with the sublethal dose of 2.5 mg dm-3 Pb 2 + as well as the partly lethal one -3.0 mg dm-3 Pb 2 + derived from two lead compounds: PbCh and Pb(N03h. 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-3 Pb 2 + from PbCh and Pb(N03h resulted 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-') was more clastogenic than lead nitrate. The presented results point to a potentially mutagenic effect of low lead doses.

The effect of Lead on early stages ofPhaseolus vulgaris L. growthin vitro conditions

“…R6derer (1986) in the unicellular alga Poterioochromonas malhamensis stated that the selective interaction of triethyl lead (organolead) with mitotic and cytoplasmic microtubules is the primary cause of the selective inhibition of mitosis and cytokinesis. The lead-induced inhibition of mitotic divisions has been described for other plants as well (Hammett 1928, Ahlberg et al 1972, ~wieboda 1976, Wierzbicka 1984, 1988, Przymusiliski and Wo~ny 1985, 1987, Romaniuk et al 1986. A reduction in growth is likely to be not only the result of a decrease in the number of mitosis processes.…”

Antioxidative defense to lead stress in subcellular compartments of pea root cells.

“…The destructive effects of lead are visible at the molecular and cellular levels as well as at the level of the whole plant [34][35][36][37]. Roots are especially endangered by the toxic lead effect, because they first have contact with the metal and they are organs where 70-95% of the lead is accumulated [38].…”

Toxicity assessment of natural waters from the Obninsk radioactive waste repository

“…For this spectrum, the absence of severe (lethal) alterations in cell (multi-polar mitoses, -mitoses, changes in the nucleus form, chromosome adhesion) is reported. Such genetic alterations in cells are caused by a combined action of radionuclides and chemicals found in water in relatively small concentrations [4,7,8].…”