title: Uptake and transformation of soil [14C]-trinitrotoluene by cool-season grasses.
abstract: This study investigated the fate and uptake of [(14)C]-TNT from soil into orchardgrass (Dactylis glomerata), perennial ryegrass (Lolium perenne), and tall fescue (Festuca arundinacea) over a one year period in a greenhouse-controlled environment. Pots (n = 4 for each grass, containing 10 mg cold TNT/kg soil + 1.2 mg [(14)C]-TNT/kg soil and controls with no TNT) were exposed to light and temperature conditions typical of June at 45 degrees N for 369 days. Three plant harvests were made (63, 181, and 369 days), and soil and plant materials were monitored for [(14)C]-TNT and metabolite concentrations. The 11.2 mg/kg TNT dose was not phytotoxic to the plant species tested. Continual uptake of TNT into grass blades was observed over the one-year period, with a total accumulation of 1.3%, 0.9%, and 0.8% of the initial soil [(14)C]-TNT dose for orchard grass, perennial ryegrass, and tall fescue, respectively. All [(14)C]-TNT residue in plant material was incorporated as bound residue. At final harvest, radioactivity was concentrated most highly in the root > crown > blade for all species. Soil TNT was gradually reduced to aminodinitro-toluenes and then further to an unidentified metabolite(s). Overall, orchardgrass appeared to be the most efficient species at taking up TNT.
authors.affiliation: Department of Environmental and Molecular Toxicology, Oregon State University, 139 Oak Creek Building, Corvallis, Oregon 97331, USA. Jennifer.Duringer@oregonstate.edu
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Duringer
authors.forename: A
authors.initials: A
authors.lastname: Morrie Craig
authors.forename: David J
authors.initials: DJ
authors.lastname: Smith
authors.forename: Rufus L
authors.initials: RL
authors.lastname: Chaney
mesh_terms: D001673:Biodegradation, Environmental; D001711:Biotransformation; D002250:Carbon Radioisotopes; D003080:Cold Temperature; D006109:Poaceae / Q000378:metabolism*; D012621:Seasons; D012989:Soil Pollutants / Q000378:metabolism*; D014303:Trinitrotoluene / Q000378:metabolism*
chemical_list: D002250:Carbon Radioisotopes; D012989:Soil Pollutants; D014303:Trinitrotoluene