The spill of petroleum drilling wastes and fluids on crop lands would produce negative effects on crops growth and development of and soil properties. In this context, oil-based drill cuttings concentrations (2, 4, 6, 8 y 10%) effect on vegetative characters of soybean (Glycine max (L.) Merr.) were evaluated. Moreover, heavy metal (Ba, Ni, Cr, Cd, Pb, Zn and Fe) concentration changes in the mixtures and their influence on plant shoot heavy metal detection were determined. Stem diameter did not show changes in 2-10% combinations, throughout the six weeks of growing; in contrast, plant height exhibited drastic reduction at week five and six with 8 and 10% doses, and leaves number showed adverse effect at week six with the mixtures of 8 and 10%. Addition of oil-based drill cuttings to savannah soil increased Ba, Cr and Zn concentrations in the mixtures but they did not overcome the stabled limits or the concentrations found in oil-based drill cuttings. Cd, Ni y Pb concentrations, steady as traces throughout drill cuttings additions (2-10%), increasing only Ba concentration, and Cr, Zn and Fe concentrations were similar. Shoot Ni, Cd y Pb concentrations maintain similar values to control (savanna soil) and soil-oil based drill cuttings mixtures (2-10%). Shoot Ba, Zn and Fe increased joined to their increment in the combinations. Accordingly to bioaccumulation coefficients (BAC), soybeans can be considered as a Fe-low accumulator (BAC=0.02-0.05), Bamoderate accumulator (BAC=0.5-0.6) and Zn-hyper-accumulator (BAC=4.3-6.2).
