Phytoremediation of soil contaminated with heavy metals using Brassica napus

In order to examine the feasibility of utilizing oil extracted from plant seed in the contaminated areas, the phytoremediation applicability of soils contaminated with heavy metals and its follow-up result in the production of biodiesel was investigated. Brassica napus was chosen as the main target plant because it is widely used for phytoremediation and is an advantage of biodiesel production. From the perspective of heavy metal concentrations in Brassica napus, plants grown in contaminated soil show significantly higher concentration than those in non-contaminated soil. From the results of sequential extraction analysis, it was also found that heavy metal concentrations in plant may be increased with the enhancement of phyto-available fraction of heavy metal in the soil. These results show the feasibility of oil production extracted from Brassica napus, which was grown in heavy metal-contaminated soil. The seed contains a low concentration of most kinds of heavy metals except Zn in soil, which is essential for seed growth. The results of oil analysis show that more than 50% of heavy metal remained in the residues. Therefore, the application of phytoremediation by Brassica napus is a feasible technique for the removal of heavy metals and its following biodiesel production as an energy source is acceptable.