Q59 · UPSC Prelims 2023 · Set A · Environment and Ecology

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Consider the following statements regarding mercury pollution :1.Gold mining activity is a source of mercury pollution in the world.2.Coal-based thermal power plants cause mercury pollution.3.There is no known safe level of exposure to mercury.How many of the above statements are correct?

A Only one
B Only two
C All three
D None

Correct answer: (b) Only two

Explanation

  1. A

    Only one

    Only one. Gold mining and coal plants are both mercury sources.

  2. B

    Only two

    Only two. ASGM and coal-fired plants release mercury. A blanket ‘no known safe level’ is not keyed as the third correct limb.

  3. C

    All three

    All three. The paper stops at two.

  4. D

    None

    None. Two pollution sources stand.

Summary. Official key is (b) only two. Artisanal gold mining (mercury amalgamation) and coal combustion are major global mercury sources. The Commission does not count the ‘no known safe level’ sentence as a third correct statement in this item.

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