Phytotoxicity to and uptake of TNT by rice.
The contamination of the environment by explosives is a worldwide problem resulting in part from 2,4,6-trinitrotoluene (TNT) production. In situ phytoremediation is an appropriate, alternative, cost-effective technology to detoxify extended contamination of surface soil. The ability of rice (Oriza sativa) to both tolerate and assimilate 14C-labeled TNT was investigated over a 40-day exposure period. The germination rate decreased at 500 mg/kg TNT whereas root and shoot length increased significantly at high TNT concentrations, from 150 to 500 mg/kg. Rice took up TNT residues from soil and accumulated most in roots. Less than 25% of radioactivity taken up was translocated to aerial parts. Above 200 mg/kg TNT, the concentration of TNT residues in roots reached a maximum of approximately 0.7 mg/g. No TNT was found in plant extracts, good evidence for rapid metabolism of TNT. More than 60% of (14)C activity was found as unextractable residues in roots. It was concluded that TNT metabolized and subsequently sequestered by roots could not be translocated to aerial parts.
Vila
M
M
INRA, UMR 1089 Xénobiotiques, 180, Chemin de Tournefeuille, BP3, F-31931 Toulouse, France.
Lorber-Pascal
S
S
Laurent
F
F
D053834:Explosive Agents / Q000378:metabolism / Q000633:toxicity*; D018525:Germination / Q000187:drug effects; D012275:Oryza / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012639:Seeds / Q000187:drug effects / Q000254:growth & development; D012989:Soil Pollutants / Q000378:metabolism / Q000633:toxicity*; D014303:Trinitrotoluene / Q000378:metabolism / Q000633:toxicity*
D053834:Explosive Agents; D012989:Soil Pollutants; D014303:Trinitrotoluene