Bioaccumulation Potentials of Momordica charantia L. Medicinal Plant Grown in Lead Polluted Soil under Organic Fertilizer Amendment

Abstract

This study investigated bioaccumulation factors and translocation factors of lead (Pb) by M. charantia so as to ascertain the bioaccumulation potentials of this medicinal plant. The elemental deposition of Pb were also assessed in order to compare the concentration of Pb present in plant tissues with the maximum permissible limits of 10 ppm recommended by WHO (1998, 2007). The experiment was a factorial combination of one heavy metal (Pb) at five levels of concentrations (0, 200, 400, 800 and 1,000 ppm) in a completely randomized design, replicated three times, with one medicinal plant species and two levels (0 and 9.4 g) of organic fertilizer (OBD- Plus). The seedlings were transplanted from nursery to experimental pots at the rate of one seedling per pot and grown for 10 weeks, after which the plants were harvested and dried for the analysis of Pb concentration both in soil and plant tissues using Atomic Absorption Spectrophotometry (AAS). The highest bioaccumulation factor for roots was 0.42 under fertilizer amendment, whereas the highest bioaccumulation factor for shoots was 0.26 under the same treatment. The highest transfer factor of M. charantia was 0.6. The results showed that M. charantia is a good phytostabilizer of Pb component. The highest lead deposition in the roots, which was 40% higher than in the shoots concentration, was above the safe limit; therefore this might pose health risks to human if consumed as herbal medicine.