Heavy metal uptake by spinach leaves grown on contaminated soils with lead, mercury, cadmium, and nickel.

Spinach plants were grown in soil pots contaminated with increasing mixtures of lead, mercury, cadmium, and nickel salts. Plants in the control soil were grown in the absence of the heavy metals mixture. The elemental distribution of Cd, Ni, Pb, and Hg in the roots and leaves of Spinach (Spinacia Oleracea) was determined in two stages, Stage 1, after five weeks of plant growth and Stage 2, after 10 weeks with full growth. Under the influence of contamination of soil with the heavy metal mixtures, Hg was the most accumulated element in the root of the spinach plant with a concentration of 283 ppm recorded in the highest contaminated soil, followed by Cd at 148 ppm.