Toxicity characterization of organic contaminants in industrialized UK estuaries and coastal waters

This report describes the isolation and identification of organic toxicants present in marine surface waters collected from industrially impacted area s around the UK in 1997, The characterization process utilized Toxicity Ide ntification Evaluation (TIE) procedures that have been adapted for marine s amples and a small volume bioassay using the marine copepod Tisbe battaglia i. The dissolved organic content of bulk water samples was isolated using a layered solid phase extraction system to provide sample concentrates which were tested for acute toxicity. Where acute toxicity was demonstrated, the extracts were fractionated using reverse phase HPLC and tested further, Ea ch fraction showing toxicity was then analysed by gas chromatography-mass s pectrometry, The results of this investigation demonstrate that surface wat er concentrates collected from several impacted estuaries show acute toxici ty. Organic extracts from surface waters may be concentrated using simple c hromatographic techniques to induce toxicity in test species. Fractionation showed that the majority of this toxicity is associated with low to medium polarity contaminants. Compounds that were identified by gas chromatograph y-mass spectrometry as the possible cause of toxic effect include alkylphen ols, alkyl substituted naphthalenes, alkyl-substituted fluorenes and dimeth yl benzoquinone, however, the identity of certain toxic compounds remains u nknown. It is concluded that the technique is a valuable tool in identifyin g compounds that may be potentially harmful to the aquatic environment, Cro wn copyright (C) 1999 Published by Elsevier Science Ltd. All rights reserve d.