Although no particular studies have been made of pollutants in fish of the Forth and Tay estuaries, samples from these areas have been examined together with similar samples from other Scottish coastal waters, as part of a national survey of marine pollution. The contaminants investigated so far have been organochlorine compounds, including pesticide residues and polychlorinated biphenyls, mercury (including organic mercury), lead, cadmium, copper and zinc. Pelagic and demersal fish, molluscs and Crustacea have been sampled, although not all contaminants have been determined in all species.

Few samples have been obtained from the upper sections of the two estuaries, but in comparison with residue levels found in other Scottish waters the species in the two areas contained concentrations little different from those considered to be normal. The selection of species and tissues for analysis, and the problems of interpretation of the analytical data, in terms of locating the sources of pollution and assessing the effects of the pollutants on fish, are discussed. More detailed surveys would be required to identify any localised areas of high contamination.