Over the last few years, contamination of water bodies by Cr (VI) has increased around the world. Cr (VI), a highly toxic and strong oxidizing agent produced mainly from the anthropogenic sources such as tanneries, steel, textile, cement and many other industries, whose effluents are frequently released into aquatic bodies. Fish, one of the important aquatic dwellers, are therefore more susceptible to Cr (VI) exposures. Increasingly, human beings are using fish as a protein source, either directly or indirectly as a feedstock for their domestic animals. Adverse effects on their health hence may also have a direct bearing to humans and other animals. Till date reports on toxicological impacts of Cr (VI) on fish health are inadequate. The work presented in this monograph, fill the above gap and reveal acute as well as chronic exposure impact of Cr (VI) on fish endocrine and nonendocrine biomarkers. The doses of Cr (VI) used in present study were comparable or lower than the levels recently reported from contaminated surface and ground water resources. The present study thus provides evidence for the health status of fish and other organisms exposed at these sites.