Biological transformation of 2,4-dinitrotoluene under denitrifying conditions

The anoxic biotransformation of 2,4-dinitrotoluene (DNT) was evaluated. Two denitrifying enrichment cultures were developed, one with inoculum from the biological treatment plant at Radford Army Ammunition Plant (RAAP), which was acclimated to treatment of DNT munitions wastes, the other derived from an activated sludge not routinely exposed to nitroaromatics (Urbana). DNT was cometabolically transformed by both cultures when an external carbon source was supplied. Initial transformations were reductive, with the transient accumulation of 2-amino-4-nitrotoluene, 4-amino-2-nitrotoluene, and 2,4-diaminotoluene. In addition, formation of 2-nitrotoluene and 4-nitrotoluene occurred by reductive deamination of the corresponding aminonitrotoluenes. 6-Nitroindazole was also identified as a significant metabolite from DNT in both cultures. A radioactive $\rbrack\sp{14}\rm C\lbrack$-DNT tracer, used to track the fate of the DNT, revealed that DNT was not mineralized in either culture. In addition, a significant fraction of the original DNT was transformed to insoluble products (33-40%), possibly by polymerization of 2,4-diaminotoluene. Furthermore, there was a significant difference in the composition of the soluble products from each culture. In the Urbana enrichment, most of the soluble products were hydrophilic, while in the RAAP enrichment, the majority of the products were hydrophobic. Ion pairing chromatography was used to partially characterize hydrophilic products in the Urbana enrichment. Approximately equal amounts of negatively charged and neutral compounds were detected. Mass spectroscopy of the hydrophobic products in the RAAP enrichment indicated the presence of the acetylated metabolites 4-acetamidetoluene and 4-acetamide-2-nitrotoluene.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Civil and Environmental Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Noguera Camacho, Daniel Ricardo

Contributors dc:contributor

• Freedman, David L.

• Biology, Microbiology
• Engineering, Civil
• Engineering, Environmental

Statement dc:rights

• Copyright 1996 Noguera Camacho, Daniel Ricardo

Language dc:language

eng

Identifier

AAI9625172
(UMI)AAI9625172

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/22491