Q. Consider the following statements:

Other than those made by humans, nanoparticles do not exist in nature.
Nanoparticles of some metallic oxides are used in the manufacture of some cosmetics.
Nanoparticles of some commercial products which enter the environment are unsafe for humans.

Which of the statements given above is/are correct?

1 only
3 only
1 and 2
2 and 3

Answer: (d) 2 and 3

Nanoparticles

Nanoparticles are spherical, polymeric particles composed of natural or artificial polymers.
A nanoparticle or ultrafine particle is a particle of matter 1 to 100 nanometres in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 100 nm in only two directions.
Nanoparticles occur widely in nature and are objects of study in many sciences such as chemistry, physics, geology and biology. A significant fraction (by number, if not by mass) of interplanetary dust, that is still falling on the Earth at the rate of thousands of tons per year, is in the nanoparticle range; and the same is true of atmospheric dust particles. Many viruses have diameters in the nanoparticle range. Iron oxides/sulfides, silver, and gold are some of the representative examples of naturally-occurring nanoparticles in the environment.
Many cosmetic products used in our daily life are made with the assistance of nanotechnologies. Among metal and metal oxide nanoparticles (NPs) potentially present in cosmetics, those containing titanium dioxide and zinc oxide are common ingredients added to obtain a sufficient sun protection. The addition of silver and gold NPs is also mentioned to increase the antimicrobial and healing properties of some cosmetic formulations.
The exposure of nanoparticle to environment and human can be described through different mechanisms. Primarily occupational exposures occur to workers (including engineers, scientists, and technicians) during the research-scale synthesis and commercial production of nanomaterial-based products. This exposure mainly results from handling of raw materials while carrying out reactions through the equipment.
Characterization of resulting material, packing, and transportation can be other sources of this type of exposure. At the second stage, consumers are exposed to such nanomaterial during usage and application and it may lead to harmful and toxic effects.