Abstract

ENVIRONMENTAL MERCURY TOXICITY IN FISH: AN OVERVIEW

Dr. Govind Pandey*

Abstract

Natural aquatic system may extensively be pollutated with mercury (Hg) released from domestic, industrial and other man-made activities. With increasing Hg in the environment, this heavy metal (element) enters the biogeochemical cycle. This can enter from the pollutated water into fish body by different routes and accumulates in the fish. The Hg is concentrated at different levels in the fish body. The fish may be more greatly affected by the water pollution sources. They are highly exposed from Hg, leading to severe toxicity. In this manner, the fish accumulate substantial concentrations of Hg in their tissues and so they are the single largest sources of Hg for humans through their eating. The organic forms of Hg (e.g., methyl Hg) are more toxic than the inorganic forms due to ease of absorption into the human system. The organic Hg compounds are most toxic to central nervous system (CNS), and may also affect the kidney and immune system. Main symptoms of Hg poisoning in human beings include kidney damage, disruption of nervous system, damage to brain function, DNA and chromosomal damage, allergic reaction, sperm damage, birth defect and miscarriage.

Keywords: Aquatic environment, fish, heavy metals, mercury, pollution, toxicity.