The Effects of Mercury Exposure on Neurological and Cognitive Dysfunction in Human: A Review

Mercury (Hg) is a naturally occurring noxious and volatile heavy metal found in the environment in the various forms. In the environment mercury is released via natural (weathering of rocks, volcanic eruptions) and anthropogenic activities (mining, coal fired power stations, waste incineration and industrial processes. Mercury occurs in inorganic and organic form; inorganic form consists of metallic or elemental mercury (Hg) whereas organic form covers Hg bound compounds like methyl, ethyl and phenyl mercury. By the assistance of certain microorganisms mercury can be transformed into its toxic form, namely methylmercury (MeHg). Methylmercury can act as a neurotoxin and bioaccumulates in the tissues of aquatic plants and animals and can affect the health of individuals who eat these animals and fishes. High exposure to mercury engenders complications like changes in the central nervous, digestive and immune system besides this, it also have toxic effects on liver, lungs and kidneys. Neurological and cognitive and motor dysfunction may be noticed after ingestion, inhalation or by any kind of exposure to mercury compounds. Patients with high mercury exposure show symptoms like nausea, irritability, tremors, headache, hypertension, hallucinations and even death in certain cases. Resourceful approach should be taken to evaluate the risk of occupational exposure and also to consuming fish with regard to human and animal health. Current chapter will discuss all the problem findings and recent advances of mercury poisoning and their effect on neurological functions.