Fish Biomarkers, Suitable Tools For Water Quality Monitoring

A large number of biomarkers and indicator organisms have been suggested for the assessment of ecotoxicity of man-made compounds onaquatic environments. The physiological and biochemical indices in fishes are sensitive for detecting potential toxic effects, and also are obviousfrom the same reports that studies on the impact of pollutants on the physiological and biochemical status of aquatic organisms. In anattempt to define and measure the effect of pollutants on an ecosystem, biomarkers have attracted a lot of interest. The underlying principleof the biomarker approach is the analysis of an organism’s physiological or biochemical response to pollutant exposure. The measurement ofbiochemical and physiological parameters is a diagnostic tool commonly used in aquatic toxicology and bio-monitoring, so Hematologicaland immunological parameters are suitable biomarkers in mercury studies. During stress, fish respond in a number of ways in order to regainhomeostasis and two important physiological processes which are modulated when fish are exposed to stress, are hormonal status and immunefunction. In this paper, our previous research's on effects of different pollutants (heavy metals, pesticides, nano particles, organic pollutants andetc.) on many fish species (marine and freshwater) was studied to detect new biomarkers (enzymatic, hormonal, immunological, hematological,histopathological and etc.) for water quality monitoring. In this study we examined markers of hematology, enzyme, hormone and histopathologyin different fishes. The aim of this study was to test a multi-trial biomarker approach for evaluating toxicological risk due to the majortoxicant in the water, using fishes as bio-indicator organism. The main objectives of this researches were: to identify the tissues and biologicalmaterials useful for biomarker studies; to evaluate various biochemical biomarkers in different tissues; to identify the most suitable biomarkersfor evaluating chemical stress due to the contaminants explored in this study.