The use of a short-term cellular subcellular biomarkers strategy is being explored to answer accurately and economically some of these questions about bodies of water, with emphasis on estuaries. According to the biomarker concept, the authors should be able to predict whole-organism responses from subcellular, and tissue indicators. Among the possible biomarkers they are exploring are the following; selected biochemical and immunological changes, including mixed-function oxidase induction, phagocytosis and antibody agglutination; several mutation indicators, such as the Ames test, sister chromatid exchange, DNA unwinding, a Salmonella DNA repair induction test(SOS); and a proposed test for tumor promoters (metabolic cooperation assay (V79/MC). Also planned are studies to detect and identify DNA adducts and micronuclei. The results of these studies will be correlated to histopathologic findings. The final goal of the research is to identify the most appropriate biomarkers to detect environmental problems, determine the sources of these problems, and predict the impact of pollution on humans and other animals. Ultimately the information should be useful in reducing risks to human health and the environment.