USING SYSTEMATIC AND COMPARATIVE ANALYTICAL DATA TO IDENTIFY THE SOURCE OF AN UNKNOWN OIL ON CONTAMINATED BIRDS

A tiered and integrated analytical approach for identification of the source of an unknown oil on contaminated birds by use of systematic an d comparative GC-MS and GC-flame ionization detection data is describe d. Characterization of the unknown oil was achieved through a variety of ''standard'' analyses including not only individual aliphatic, arom atic and biomarker hydrocarbon analysis, but also ''source-specific-ma rker'' diagnostic ratio analysis. Once precise chemical data were obta ined and data analysis and comparison with the corresponding data from the known oils was completed, product identification (fingerprinting) techniques were used to identify the type of product present, and to estimate the degree of weathering the product had undergone since rele ase. It was concluded that: (I) the residual oil on the birds was most probably an old Bunker C type oil and not from the suspected barge oi l; (2) the oil on contaminated birds was relatively highly weathered a nd (3) some biodegradation of the oil had occurred. (C) 1997 Elsevier Science B.V.