Nanotechnology has been described by the National Nanotechnology Initiative (NNI) as "The understanding and control of matter at dimensions between 1 and 100 nanometers, where unique phenomena enable novel applications."

Many nanomaterials have unique optical, mechanical, thermal, electrical, catalytic and even magnetic properties. The increased understanding of nanoparticle production has lead to new consumer products, materials and applications across many different disciplines. Some of these disciplines include cosmetics, medicine, aerospace, energy and transportation. Nanotechnology and the resulting products developed through this emerging science will continue to increasingly impact almost every walk of life.

Today, the potential for long-term health risks associated with nanoparticles are not well understood. Studies have suggested that excessive exposure to nanoparticles could cause lung damage, cell toxicity, damage to people's DNA and possibly even harm unborn children.

The use of nanoparticles in cosmetics is one of the most studied areas of use in consumer products. The tiny particles can be inhaled or ingested into the body. Once the particles have entered the body they can be absorbed into the blood stream, tissues and organs.

In addition to concerns over possible health effects due to exposure to nanoparticles in consumer goods, people working in industries that manufacture and process nanoparticles may also face concerns due to repeated exposure to the materials.

Nano-sized particles commonly used today include: aluminum, titanium dioxide, silicon oxide and iron oxide. In addition to these particles, carbon nanotubes (single walled or multi-walled) have a variety of uses.