This transition of mercury has an important impact on human, since people who consume methyl mercury will become defenseless of its effect. Once mercury consumed by small fishes, it then moves its way up the food as larger fishes consume contaminated smaller fishes. Instead of breaking down or dissolve, mercury tends to accumulate at a higher level and will cause serious side effect on human, especially children and pregnant women. This is due to the fact that children's brain is relatively fragile and still budding during the first several years of life, prenatal or infant mercury exposure can cause deafness, blindness, and mental retardation according to Mayo Clinic. Not only does mercury poses a health threat to children and pregnant women, it can also effect fertility as well as blood pressure regulation and heart disease in adult. Despite its useful role in the industrial industries, mercury contamination in water is gradually becoming a huge threat to both animals in the water and the people who consume it, especially pregnant women and children.
For more information about mercury contamination in water, visit http://water.usgs.gov/wid/FS_216-95/FS_216-95.html