UPSC Prelims 2014 Question:

There is some concern regarding the nanoparticles of some chemical elements that are used by the industry in the manufacture of various products. Why?

1. They can accumulate in the environment and contaminate water and soil. 
2. They can enter the food chains. 
3. They can trigger the production of free radicals.
   
   

Select the correct answer using the code given below:

Explanation:

• Nanoparticles are molecules which are sub-100 nm in range, and have specific physical, chemical and biological properties. These properties make them as potent molecules for diagnostics and therapeutics in modern medicine. Nanoparticles are widely used because of their desirable properties in industrial, medical and cosmetic fields.
  
  
• Nanoparticles can accumulate in environment as some of them are stable. They can enter the food chains. They can also trigger the production of free radicals and cause oxidative stress following exposure at a cellular level.
  
  

Therefore, option (4) is the correct answer.

Subject: Science & Technology | Nanotechnology