METABOLITES OF 2-CHLOROSYRINGALDEHYDE IN FISH BILE - INDICATOR OF EXPOSURE TO BLEACHED HARDWOOD EFFLUENT

1. 2-Chlorosyringaldehyde (2-CSA) is the major chlorinated phenol prod uced by the 100% chlorine dioxide bleaching of eucalypt pulp and is fo und in other bleached hardwood effluents. Almost nothing is known of t he environmental or metabolic fates of this chemical. 2. Sand flathead (Platycephalus bassensis) was given 2-CSA by intraperitoneal injectio n at 0.15, 1.5, 15 and 75 mg/kg doses and, 4 days later, bile was coll ected and solvent extracted before and after enzymatic cleavage of con jugates. The acetate derivatives of bile extracts were analysed by gas chromatography/mass spectrometry. 3. The major metabolite 4 days afte r administration was the glucuronide or sulphate conjugate of 2-chloro -4-hydroxy-3,5-dimethoxy-benzylalcohol (2-CB-alcohol). The identity of 2-CB-alcohol was confirmed by chemical synthesis. 4. The quantity of 2-CB-alcohol in the bile was linearly related to dose of 2-CSA and was detected at all dose levels. Minor metabolites identified were conjug ated 2-CSA, unchanged 2-CSA and 2-chloro-4-hydroxy-3,5-dimethoxy-benzo ic acid. 5. The amount of 2-CB-alcohol in bile has the potential to be a sensitive and specific indicator of fish exposure or bleached hardw ood effluent.