Figen Esin KAYHAN
It is very important to apply biochemical, histologic and histopathological methods evaluating pollution degrees from heavy metals in sublethal levels in both clear and polluted areas. In aquatic organisms, biochemical defects are observed as primary responses due to heavy metals following stress and from their physiological effects secondary responses develops. Secondary responses may be evaluated by changes in histologic, histopathologic, biochemical and hematologic parameters. In this compilation study, it was aimed to explicate general health problems, stress and also biological responses observed due to these factors which are caused by toxic heavy metal accumulations in aquatic organims.