Phytoremediation for co-contaminated soils of chromium and benzo[a] pyrene using Zea mays L.

A greenhouse experiment was carried out to investigate the single effect of benzo[a] pyrene (B[a] P) or chromium (Cr) and the joint effect of Cr-B[a] P on the growth of Zea mays, its uptake and accumulation of Cr, and the dissipation of B[a] P over 60 days. Results showed that single or joint contamination of Cr and B[a] P did not affect the plant growth relative to control treatments. However, the occurrence of B[a] P had an enhancing effect on the accumulation and translocation of Cr. The accumulation of Cr in shoot of plant significantly increased by >= 79 % in 50 mg kg(-1) Cr-B[a] P (1, 5, and 10 mg kg(-1)) treatments and by >= 86 % in 100 mg kg(-1) Cr-B[a] P (1, 5, and 10 mg kg(-1)) treatments relative to control treatments. The presence of plants did not enhance the dissipation of B[a] P in lower (1 and 5 mg kg(-1)) B[a] P contaminated soils; however, over 60 days of planting Z. mays seemed to enhance the dissipation of B[a] P by over 60 % in 10 mg kg(-1) single contaminated soil and by 28 to 41 % in 10 mg kg(-1)B[a] P co-contaminated soil. This suggests that Z. mays might be a useful plant for the remediation of Cr-B[a] P co-contaminated soil.