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 above statements is/are correct?
✓ Correct answer: d) 2 and 3 UPSC GS Paper-I PYQs 554
ExplanationNanoscience is the study of matter at the nanoscale dimensions between approximately 1 and 100 nanometers or 1,000 times smaller than the width of a human hair.At these incredibly small scales, materials have unique phenomena that enable new applications.Statement 1 is incorrect: Other than lab-made, nanoparticles are also naturally found in the environment and are formed through processes such as volcanic eruptions, forest fires, and photochemical reactions.Examples include naturally occurring metal nanoparticles like silver (AgNPs) and gold nanoparticles (AuNPs) in water bodies.Statement 2 is correct: Metallic oxide nanoparticles, including titanium dioxide (TiO₂) and zinc oxide (ZnO), are commonly used in cosmetics like sunscreens and makeup.These nanoparticles provide UV protection and enhance the product’s properties, such as its texture and durability.Statement 3 is correct: The increasing use of nanoparticles in commercial products has raised concerns about their environmental and health impacts.Certain nanoparticles, like titanium dioxide used in some products, have be
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