Consider the following statements :
- 1.Other than those made by humans, nanoparticles do not exist in nature.
- 2.Nanoparticles of some metallic oxides are used in the manufacture of some cosmetics.
- 3.Nanoparticles of some commercial products which enter the environment are unsafe for humans.
Which of the statements given above is/are correct ?
Show answer
Answer: D. Statement 1 is wrong: nanoparticles occur naturally, for example in volcanic ash, sea spray and smoke. Statement 2 is correct: nanoparticles of zinc oxide and titanium dioxide are used in sunscreens and cosmetics. Statement 3 is correct: some nanoparticles released into the environment can harm human health. So 2 and 3.
Watch for: 'Nano' sounds high-tech, so students assume nanoparticles are only man-made.
Why the other options are wrong
- A. Wrong because nanoparticles also exist in nature.
- B. Wrong because statement 2 is also correct.
- C. Wrong because statement 1 is incorrect.
Source to check: US FDA guidance on nanomaterials in cosmetics; WHO and OECD notes on nanomaterial safety
Answer from the official UPSC key. Written and fact-checked by AI against the official key. Spotted a mistake? Report it.