Previous Year Question
Consider the following statements regarding Mercury pollution.
Gold mining activity is a source of Mercury pollution in the world.
Coal-based thermal power plants cause Mercury pollution.
There is no known safe level of exposure to Mercury.
How many of the above statement(s) is/are correct?
Only one
Only two
All three
None
Correct Answer: C
Detailed Solution
Mercury is a naturally occurring, highly toxic element that can persist in the environment for a long period.
Mercury is used to separate gold from ore in artisanal and small-scale gold mining.
Mercury forms an amalgam with gold, and when it is heated, mercury can evaporate and enter the atmosphere.
Therefore, gold mining is an important source of anthropogenic mercury pollution in the world. Hence, Statement 1 is correct.
Coal naturally contains trace quantities of mercury.
When coal is burned in a thermal power plant, this mercury may be released into the atmosphere as a gas or along with fine particles. Therefore, Statement 2 is correct.
Mercury released into the atmosphere can travel long distances and be deposited on water, soil and vegetation.
In aquatic environments, microorganisms can convert mercury into methylmercury.
Methylmercury bioaccumulates and biomagnifies through aquatic food chains and may reach high concentrations in large predatory fish.
Mercury can affect the central nervous system, kidneys, digestive system, immune system and lungs.
Fetuses and young children are particularly vulnerable to the neurodevelopmental effects of mercury.
There is no known completely safe level of exposure to mercury. Therefore, Statement 3 is correct.
The severe neurological disease caused by methylmercury pollution in Minamata Bay, Japan, became known as Minamata disease.
The Minamata Convention on Mercury was adopted in 2013 and entered into force in 2017.
Its objective is to protect human health and the environment from mercury emissions, use, trade and waste.