Enhanced desorption of PCB and trace metal elements (Pb and Cu) from contaminated soils by saponin and EDDS mixed solution

► A novel combination of biosurfactant saponin and EDDS was used to simultaneously remove mixed contaminations from soil. ► Significant synergy on Pb, Cu and PCB desorption were achieved with EDDS/saponin. ► The marked interaction between EDDS and saponin contributed to the synergy performance.