Fish are regarded as valuable organisms in monitoring aquatic ecosystems.
They are established as indicator organisms and widely used in both laboratory studies
and ecotoxicology. A range of biomarkers are developed for monitoring effects of
xenobiotics on fish. Histopathology is classified as an important biomarker in terms of
toxicological significance and highly relevant when chronic or sublethal pollutants are
present in the water. In this chapter, a short review of histopathological methods is
given, with basic guidelines for conducting field studies. The main focus is on different
methods for quantifying alterations, namely: semi-quantitative scoring system,
histomorphometry and stereology. Advantages and shortcomings of each method are
briefly discussed.
Keywords: Ecotoxicology, Fish, Histomorphometry, Quantification, Semiquantitative
scoring system, Stereology.
