Sediments from four inshore industrial sites and a reference site in the Great Lakes were extracted with organic
solvents to produce a
crude extract, which was separated on
alumina into two fractions: predominantly
polycyclic aromatic hydrocarbons; and predominantly
nitrogen-containing polycyclic aromatic compounds.
Crude extracts were redissolved in
acetone and analyzed by gas chromatography and gas chromatography-mass spectrometry. The
acetone-redissolved
crude extracts from the four industrialized sites contained 5.6-313.3 micrograms total polycyclic aromatic compounds/g sediment and 3.0-36.4 micrograms other compounds/g sediment. In addition to the typical EPA priority
pollutants, a substantial amount (228.7 micrograms/g sediment) of alkyl-polycyclic-aromatic compounds was detected in sediments from one of the industrialized sites. Extracts from the reference site contained 1.55 micrograms total polycyclic aromatic compounds/g sediment. Medaka (Oryzias latipes) were exposed to multiple pulse doses of
acetone-redissolved extracts and fractions. Medaka were also exposed to a known
carcinogen,
methylazoxymethanol acetate, to verify that chemicals produced
tumors in the test fish.
Acetone-redissolved extracts and fractions from contaminated sediments were toxic to medaka. Fin erosion and non-neoplastic liver abnormalities were more prevalent in medaka after exposure to
acetone-redissolved extracts and fractions from contaminated sediments.
Neoplasms previously associated with chemical exposure in wild fishes were induced in medaka exposed to
acetone-redissolved extracts and fractions from two of the contaminated sites, but not from the reference site or controls. These findings further support the hypothesis that chemical contaminants in sediments are involved in epizootics of
neoplasms in wild fishes at contaminated sites.