The final, formatted version of the article will be published soon.
ORIGINAL RESEARCH article
Front. Environ. Sci.
Sec. Toxicology, Pollution and the Environment
Volume 12 - 2024 |
doi: 10.3389/fenvs.2024.1426203
This article is part of the Research Topic Environmental Remediation Strategies of New and Emerging Chemical Contaminants View all 12 articles
Enhanced Biodegradation of Trinitrotoluene (TNT) in Rhizosphere Soil by Selected Native Grasses
Provisionally accepted- 1 Liaoning Academy of Agricultural Sciences, Shenyang, Liaoning Province, China
- 2 Lincoln University, Jefferson City, United States
- 3 University of Missouri, Columbia, Kentucky, United States
Soil contamination by the munition explosive residues of 2,4,6-trinitrotoluene (TNT) and its metabolites resulting primarily from military operations has beenwas identified as a threat to human health and ecosystems. TNT and its metabolites are persistent in the environment and toxic to human health. Conventional remediation methods of TNT-contaminated soils included incineration, composting, or bioslurry. However, The biodegradation by native plants thatto removes this hazardous compound or reduces its toxicity has is beingen considered as athe most cost-effective and environmental-sound approach for the cleanup orand restoration of TNT-contaminated sites soils, which is little reported. This study was aims to investigate the TNT biodegradation and kinetics by in two selected native grasses in the species-specific rhizosphere soils through growth chamber experiments. Native Eeastern gamma grass (Tripsacum dactyloides) and switchgrass (Panicum virgatum L.) were grown in the soil spiked with 14 C-TNT for 8 weeks. The 14 C-TNT mineralization ratesdegradation and degradativeon metabolite profiles in the rhizosphere soils were determined by liquid scintillation counter and high-performance liquid chromatography coupled with an online scintillation counter, respectively. Results indicated that both native grass species have significantly enhanced the 14 C-TNT mineralization or degradation in the rhizosphere soils as compared with the control rhizosphere soils. More than 95% of the applied 14 C-TNT was degraded in the first 7 days, and the rate then reached a steady state afterwards, but less than 10% of the TNT applied werewas completely mineralized and transformed into CO2. The degradative reactionon was found to follow second-order kinetics. Six major TNT degradative metabolites have been were detected and identified in the rhizosphere soils. Overall, switch grass appeared to be more effective for biodegrading TNT than eastern gamma grass. This study research demonstrated that the native grass species, especially switch grass, wouldcould have the potential to mitigate the adverse human health and ecologicalenvironmental risks of TNT-contaminated sites and canto be considered as an environmental-friend, sustainablesound remediation approach to safeguard the human health from the TNT contamination.
Keywords: TNT, Biodegradation, native grass, rhizosphere soil, remediation
Received: 30 Apr 2024; Accepted: 03 Sep 2024.
Copyright: © 2024 Li, Yang, Lin and Yang. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence:
John Yang, Lincoln University, Jefferson City, United States
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.