Uptake and Phytotransformation of o,p‘-DDT and p,p‘-DDT by Axenically Cultivated Aquatic Plants

The uptake and phytotransformation of o,p‘-DDT and p,p‘-DDT were investigated in vitro using three axenically cultivated aquatic plants:  parrot feather (Mariophyllum aquaticum), duckweed (Spirodela oligorrhiza), and elodea (Elodea canadensis). The decay profile of DDT from the aqueous culture medium followed first-order kinetics for all three plants. During the 6-day incubation period, almost all of the DDT was removed from the medium, and most of it accumulated in or was transformed by these plants. Duckweed demonstrated the greatest potential to transform both DDT isomers; 50−66% was degraded or bound in a nonextractable manner with the plant material after the 6-day incubation. Therefore, duckweed also incorporated less extractable DDT (32−49%) after 6 days than did the other plants. The capacity for phytotransformation/binding by elodea is between that of duckweed and parrot feather; ∼31−48% of the spiked DDT was degraded or bound to the elodea plant material. o,p‘-DDD and p,p‘-DDD are the major meta...