Fate and metabolism of o -toluidine in the marine bivalve molluscs Mytilus edulis and Crassostrea gigas
Abstract
The in vivo fate and metabolism of a model aromatic amine (o-toluidine) were determined for mussels (Mytilus edulis) and oysters (Crassostrea gigas). o-Toluidine was found to be relatively nontoxic and was rapidly turned over in mollusc tissues. The biotransformation of o-toluidine and N-acetyl-o-toluidine was determined by the extraction and analysis of eliminated metabolites. The metabolism of [14C]o-toluidine in both bivalve species resulted in the formation of 2-nitrosotoluene, N-methyl-o-toluidine and N-formyl-o-toluidine. Small amounts of N-hydroxy-o-toluidine were detected in experiments with M. edulis. Mussels were found to be capable of N-deacetylation but oysters were not. The total extent of o-toluidine and N-acetyl-o-toluidine biotransformation in mussels from pristine waters was found to be greater than in mussels from contaminated waters.
The formation of N-oxidized metabolites is toxicologically important because this pathway constitutes the route of activation for mutagenic and carcinogenic aromatic amines. The formation of an N-formyl metabolite by these bivalves is also interesting, as this detoxication pathway has not been previously reported for marine invertebrates. The lack of carbon oxidizing pathways in these bivalves may be of limited toxicological significance because of their ability to utilize other detoxification (N-conjugation) pathways.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 2496758
- Journal Information:
- Environmental Toxicology and Chemistry, Journal Name: Environmental Toxicology and Chemistry Journal Issue: 4 Vol. 4; ISSN 0730-7268
- Publisher:
- Oxford University PressCopyright Statement
- Country of Publication:
- United States
- Language:
- English
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