5.1 Polychaetes are an important component of the benthic community, in which they generally comprise 30 to 508201;% of the macroinvertebrate population. They are preyed upon by many species of fish, birds, and larger invertebrate species. Larger polychaetes feed on small invertebrates, larval stages of invertebrates, and algae. Polychaetes are especially sensitive to inorganic toxicants and, to a lesser extent, to organic toxicants (1).3 The ecological importance of polychaetes and their wide geographical distribution, ability to be cultured in the laboratory, and sensitivity to contaminants make them appropriate acute and chronic toxicity test organisms. Their short life cycle enables the investigator to measure the effect of contaminants on reproduction.
5.2 An acute toxicity or chronic text is conducted to obtain information concerning the immediate effects of an exposure to a test material on a test organism under specified experimental conditions. An acute toxicity test provides data on the short-term effects, which are useful for comparisons to other species but do not provide information on delayed effects. Chronic toxicity tests provide data on long-term effects.
5.3 A life-cycle toxicity test is conducted to determine the effects of the test material on survival, growth, and reproduction of the test species. Additional sublethal endpoints (for example, biochemical, physiological, and histopathological) may be used to determine the health of the species under field conditions.
5.4 The results of acute, chronic, and life-cycle toxicity tests can be used to predict effects likely to occur on marine organisms under field conditions.
5.5 The results of acute, chronic, or life-cycle toxicity tests might be used to compare the sensitivities of different species and the toxicities of different test materials, as well as to study the effects of various environmental factors on the results of such tests.
5.6 The results of acute, chronic, or life-cycle toxicity tests might be an important consideration when assessing the hazards of materials to marine organisms (see Guide E1023) or when deriving water quality criteria for aquatic organisms (2).
5.7 The results of acute, chronic, or life-cycle toxicity tests might be useful for studying the biological availability of, and structure activity relationships between, test materials.
5.8 The results of acute, chronic, and life-cycle toxicity tests will depend partly on the temperature, quality of food, condition of test organisms, test procedures, and other factors.
1.1 This guide covers procedures for obtaining data concerning the adverse effects of a test material added to marine and estuarine waters on certain species of polychaetes during short- or long-term continuous exposure. The polychaete species used in these tests are taken from laboratory cultu......
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