Characterization of products from the biotransformation of 2,4-dinitrotoluene by denitrifying enrichment cultures

$30.00 plus tax (Refund Policy)

Buy Article:

Abstract:

Anoxic biotransformation of 2,4-dinitrotoluene (DNT) was examined and two denitrifying enrichment cultures were developed. In one, the inoculum was acclimated to treatment of munitions wastewater that contains DNT; the other was derived from activated sludge that was not routinely exposed to nitroaromatics. DNT was consumed readily by both cultures only when ethanol was provided as a primary substrate, with the rate of transformation twice as fast in the acclimated culture. [14C]DNT was used to track the metabolites. A negligible amount of the DNT was mineralized. The principal initial biotransformation pathway was reduction of DNT to aminonitrotoluenes. Subsequent transformations in the acclimated culture resulted in formation of 6-nitroindazole, 2-nitrotoluene, and 4-nitrotoluene, which have not previously been reported as metabolites from DNT. Acetylation at the para position was another important transformation pathway in the acclimated culture, resulting in accumulation of 4-acetamide-2-nitrotoluene and 4-acetamidetoluene. Reduction of aminonitrotoluenes to 2,4-diaminotoluene also occurred, followed by conversion of approximately one-third of the 14C activity to nonfilterable material. The majority of the soluble DNT metabolites from the unacclimated culture were hydrophilic; these were characterized by gradient elution high-pressure liquid chromatography analysis and ion pairing chromatography as approximately equal amounts of negatively charged and neutral compounds. The diversity and characteristics of these metabolites indicates that biotransformation of DNT under anoxic conditions does not necessarily eliminate the toxicological hazards associated with the parent compound. Metabolite formation should be taken into consideration when determining discharge criteria for DNT-contaminated wastewaters exposed to denitrifying environments.

Keywords: ACETYLATION; AROMATICS; DENITRIFICATION; DINITROTOLUENE; MUNITIONS WASTES; NITROAROMATICS

Document Type: Research Article

DOI: http://dx.doi.org/10.2175/106143097X125434

Publication date: May 1, 1997

More about this publication?
  • Water Environment Research® (WER®) publishes peer-reviewed research papers, research notes, state-of-the-art and critical reviews on original, fundamental and applied research in all scientific and technical areas related to water quality, pollution control, and management. An annual Literature Review provides a review of published books and articles on water quality topics from the previous year.

    Published as: Sewage Works Journal, 1928 - 1949; Sewage and Industrial Wastes, 1950 - 1959; Journal Water Pollution Control Federation, 1959 - Oct 1989; Research Journal Water Pollution Control Federation, Nov 1989 - 1991; Water Environment Research, 1992 - present.
  • Editorial Board
  • Information for Authors
  • Submit a Paper
  • Subscribe to this Title
  • Membership Information
  • Information for Advertisers
  • WEF Bookstore
  • ingentaconnect is not responsible for the content or availability of external websites

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more