PH06 Agrochemicals, Pesticides, Pharmaceuticals
Exhibit Hall
8:00 AM - Thursday
(PH049) Evidences on contamination of a benthic environment by a brominated benzonitrile herbicide (Bromoxynil).
Saint-Louis, R1, Pelletier, E1, 1 Institut des Sciences de la Mer de Rimouski, Rimouski, Quebec, Canada
ABSTRACT- Mass spectrometric analysis, involving GC-MSMS and HPLC-ESI-MSMS, demonstrated that the marine benthic environment of the Saguenay fjord (Quebec, Canada) was subject to the input of a brominated compound, possibly from agricultural sources. The chemical was quantified in the sediments at concentration as high as 5000 ng g -1 dry weight in cores sampled at a water depth between 90 to 270 m. This compound was concurrently detected in marine invertebrates at concentration levels in the range from 10 to 1600 ng g -1 dry weight. This wide range of concentrations indicates that the compounds was not a natural product synthesized by benthic organisms. However, no correlation between the level of contamination in the sediment and the concentration in the animals was demonstrated. Results from MSn experiments on the tissues extracts strongly suggest that 4-(aminocarbonyl)-3,5-dibromophenyl butyrate was a likely candidate; it could be produced from the metabolism of largely used bromoxynil ester formulation herbicides. To our knowledge, this is the first report on bromoxynil contamination of a marine ecosystem.
Key words: sediment, bromoxynil, herbicides, degradates