Another approach for remediation of：pesticides is to add the purified enzyme responsible for biodegradation。 This direct approach to remediation is limited by the ability of the enzyme to function in less than ideal conditions，in pure form without co-factors，and it must have a cheap source of isolation Sutherland et al.，2004）。In one case study， 84，000 L of methyl-parathion-contaminated waste water was treated with purified microbial enzymes with a ten-fold reduction in contaminant level in just 10 minutes（Russell et al.，2001）。Chlorpyrifos can be detoxified with mammahan paraoxonase，PON1，an enzyme that can be produced in culture and purified for use in treatment of exposed individuals（Stevens et al.，2008）。It can also be produced as a stable foam for emergency treatment of pesticide spills in the environment（C. Furlong，personal communication）。Development of inexpensive， large-scale production of PON1 using tobacco chloroplast engineering is underway Doty，unpublished）。
Phytoremediation of pesticides can be effective on several levels including reduction of chemical leaching，aerating the soil， and providing nutrients for microbial biodegradation，as well as direct uptake and phytodegradation of the pollutants Hussain et al.，2009）。 A naturally tolerant plant species，Lolium multiflorum， was able to germinate and grow in high levels of atrazine（Merini et al.，2009）。 This ability was strongly inhibited by the P450 inhibitor l-aminobenzo-triazole，suggesting that a cytochrome P450 is responsible for the high tolerance in this species。It was demonstrated that poplar cuttings can take up atrazine and metabolize it through hydrolysis and dealkylation （Chang etal。，2005）。Aquatic plants in a constructed wetland were able to remove and retain about 25% of influent chlorpyrifos（Moore et al.，2OO2）。The ability of plants to uptake and translocate pesticides from roots to shoots varies among different plant speaes，even in hydroponics without the effects of soil binding。For example，atrazine was taken up better by Juncus effuses（soft rush）than Ludwigia peploides in which it was sequestered in roots rather than translocated to shoots Bouldin et al.，2006）。In a separate study J. effuses took up both atrazine and chlorpyrifos；however， it was better able to take up and degrade the chlorpyrifos（Lytle and Lytle，2000）。In this study，chlorpyrifos was rapidly taken up within 24 hours by this prominent wetland species。In recent research with chlorpyrifos，it was shown that poplar and willow trees are able to remove and metabolize this common organophosphate pesticide（Lee et al.，2010）。These riparian speaes have the potential to remove agricultural pollutants before they enter the waterways。