Evaluation and Relative Resistance of
Sixteen Species of Fish as Test
Animals in Toxicity Bioassays of
Petroleum Refinery Effluents
NEIL H. DOUGLAS, Graduate Research Assistant
and
W. H. IRWIN, Professor of Zoology
Oklahoma State University
Stillwater, Oklahoma
Natural waters have become increasingly polluted by a great variety of
toxic agents. One of the chief contributors to water pollution is industry.
Bioassayhas been and is being used as a means of measuring the effects of a
toxicant upon animals. The need for toxicity bioassays has increased with
increased pollution problems, resulting from new industries, new compounds
and the increased demand for freshwater. Often effluents are of such a nature
that it is impossible to measure chemically the components that are present.
Fish have been used successfully as test animals when measuring the toxicity
of industrial effluents. Many different fish have been used but comparative
studies of their reactions to a particular toxicant are uncommon. The basic
aspect of this report is concerned with the need for knowledge about the reactions of different species of fish when exposed to a particular toxicant. This
paper is the second part of four, resulting from a joint research effort concerning the relativeresistance of fresh-water fish species to petroleum refinery
effluents.
Toxicity bioassays were made to establish the difference in the resistance
or susceptibility of different species of fish to a toxic effluent.
Petroleum refinery effluent was used as a source of toxicant. The effluent samples were obtained from a single petroleum refinery and their chemical nature was not determined or considered in the study.
The over-all statistical design consisted of testing each species of fish
four times with different concentrations of different effluent samples and the
results of all species were compared with the results obtained from a common
reference species used in all tests.
The test fish were also evaluated, concerning their adaptability for use
as toxicity indicators in bioassays. Evaluations included the availability and
the reactions of the species in the laboratory before testing and in toxic solutions in the bioassays. Life history characteristics concerning each species
of fish were studied to aid in establishing their value as a test species.
Sixteen species of fish were used and all but one are represented in the
fish fauna of the U. S. The exception is a non-native, tropical aquarium
species, commonly found throughout North America in areas where environmental conditions are controlled. The species tested were: the goldfish,
Carassius auratus(Lacepede); the carp, Cyprinus carpio Linnaeus; the orange-
throat darter, Etheostoma spectabile (Agassiz); the brook stickleback, Eucalia
inconstans (Kirtland); the mosquito fish,   Gambusia affinis (Baird and Girard);
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