Correlation of Toxicity with Lead Content in Root Tip Cells (Allium cepa L.)

Abstract

The present study determines lead content in onion root tip cells (Allium cepa L.), correlating it with its toxicity. The treatment was carried at 25 +/- 0.5 degrees C using aqueous solutions of lead chloride at 0.1, 0.25, 0.50, 0.75, and 1 ppm for 12, 24, 48, and 72 h. For each treatment, a control where the lead solution was substituted by distilled water was included. After treatment, the meristems were fixed with a mixture of alcohol-acetic acid (3:1) and colored according to the technique of Feulgen. Lead content was quantified by graphite furnace absorption atomic spectrometry. The lead content in the roots ranged from 3.25 to 244.72 microg/g dry weight, with a direct relation with the concentration and time of exposure. A significant negative correlation was presented (r = -0.3629; p < 0.01) among lead content and root growth increment, and a positive correlation (r = 0.7750; p < 0.01) with the induction of chromosomic aberrations. In conclusion, lead is able to induce a toxic effect in the exposed roots, correlated with its content.

Long range correlations of the ion current in SV channels. Met3PbCl influence study

“…It is important to stress that lead is mainly toxic to living organisms, which was reported in various publications e.g. [2][3][4][5][6][7][8][9][10][11]. Lead was reported as being the second most hazardous substance, after arsenic, based on the frequency of occurrence, toxicity, and the potential for human exposure by the Agency for Toxic Substances and Disease Registry [12].…”

Human Impact in the Watershed of the Atoyac River in the Metropolitan Area of Puebla, Mexico

“…This may be due to high concentrations of Cr, Pb, Ni, and Cd, which do not allow cells to enter the subsequent mitotic phases and coincide with what was observed by [67][68][69] showing that the increase in Pb may inhibit or accelerate cell division in the root meristem. This was seen in the Rabanillo River (Z2) and Echeverría Dam (Z4), which presented high concentrations of Pb and As, and Cd, CN, and Ni, respectively, and where inhibition and decreases in the number and length of roots occurred (Figure 2) [70].…”

Mecanismos de tolerancia relacionados con la bioacumulación de plomo por Dodonaea viscosa

“…El Pb puede incorporarse a un organismo vivo a través de la respiración, la digestión y por vía cutánea (Carruyo et al, 2008). En el ser humano, la inhalación es la vía principal, pero también puede incorporarse a través de la digestión y la reabsorción en el tracto gastrointestinal, particularmente en personas con deficiencia de hierro y calcio (Wong et al, 2002).…”