Remediation of soil contaminated with 2,4-dichlorophenol by treatment of minced shepherd's purse roots

This study investigated the applicability of minced shepherd's purse root containing high peroxidase activity as a catalytic agent instead of purified and immobilized peroxidase for the remediation of soil contaminated with phenolic pollutants, using 2,4-dichlorophenol (2,4-DCP) as a model pollutant. The removal of 2,4-DCP in the soil was extremely fast when treated with peroxide and minced shepherd's purse root, and maximal removal was achieved within 10 min. Increasing the reaction temperature did not significantly influence removal of 2,4-DCP incubated with shepherd's purse. The removal of 2,4-DCP was dependent on the amount of shepherd's purse and the soil moisture content. Increasing the amount of shepherd's purse and moisture mixed with soil caused an increased removal of 2,4-DCP. Calcium peroxide was more effective than hydrogen peroxide, and maximal removal was achieved in 20 mM of both peroxides. The efficiency of 2,4-DCP removal decreased with increasing 2,4-DCP concentration but was greater than 60% at 500 to 1000 mg kg(-1). Our results provide strong evidence that shepherd's purse can be used to remediate soil contaminated with phenolic pollutants.