Enhanced extraction of heavy metals in the two-step process with the mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus

► Biological extraction of heavy metals from chromated copper arsenate (CCA) treated wood. ► The removal rates of CCA-elements are strongly affected by pyruvic acid and lactic acid concentration and their combination. ► Two-step process with the mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus is most effective.