Mercury Poisoning

Case Studies of Examples - Mercury Poisoning

Introduction

Mercury is a heavy metal which can exist in different forms. It exists as liquid form at room temperature in shiny silver-coloured. The deposition and travel distance are differed due to different forms of mercury. (1) Mercury can be found from natural sources such as the weathering of rock, volcanic eruption and forest fires. Mercury in the air can fall to the ground through raindrops because of gravity which is known as air deposition. It finally ends up in streams, lakes or rivers to affect the aquatic environment. (2) Also, it can be produced by human activities like industrial processes and some metallurgic activities. Fossil fuel power production is now universally considered as the most severe source of mercury releases. Waste from industrial processes involving mercury is next in contributing to mercury emissions. Mercury is basically released in four forms during the industrial processes which are methyl mercury compounds (CH3Hg+), mercury vapor (elemental mercury), inorganic salts of mercury and several organic forms. Meth mercury can be considered as the most toxic one among the aforementioned forms. (3)

There are few ways for exposure to mercury including:

1. Taking in mercury-contaminated food especially the contaminated marine species;

2. Exposure to mercury in the environment of occupation such as the production of mercury-containing equipments as well as tooth-filling process;

3. Improper use of amalgam fills;

4. Accidentally breaking mercury-containing thermometers, manometers, CFLs and so on, thereby inhaling gaseous mercury;

5. Using some items contaminated by mercury such as cosmetics which is directly applied to human’s skin. (4)

Most people expose themselves to mercury through their diet due to the bioaccumulation of methyl mercury. The deposited elemental mercury in the atmosphere is consumed by the bacteria or microorganism in the aquatic ecosystem and then...