Increasing the Sustainable Production of Biofuels – Prospects of Cultivating Oilseed Crops in Soils Contaminated with Heavy Metals

The production of oil crops is a promising alternative for the substitution of fossil fuels to secure the production of energy, and several species can be cultivated for it. Some new oil crops are promising due to their oil yields and quality. In addition to the potential for oil production, some species are capable of toleranting heavy metals from the soil. Thus, the current work aims to explore the potential of Brassica carinata and Crambe abyssinica in soils contaminated with Zn (450 mg.kg⁻¹, dm), Pb (450 mg.kg⁻¹, dm), Cd (4 mg.kg⁻¹, dm) and Ni (110 mg.kg⁻¹, dm). B. carinata was more productive (160 g/m²), exceeding crambe (130 g/m²). Both crops showed tolerance to the heavy metals experimented (tolerance index higher than 0.75). Nevertheless, the oil content in the seeds was somewhat altered by the level of contamination in the soil. Therefore, biodiesel production costs may increase because oil production per land area is reduced due to the level of contamination. Nevertheless, the production of oil crops in soils polluted with heavy metals represent an opportunity to provide feedstock for the oil-based chemical industry, contributing to decarbonize the economy.