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You can’t see them but they are there. Nanoparticles have been used, more and more, in food packaging, pesticides, cosmetics, clothing, toys, kitchenware and more over the past few years. They have been considered nothing less than revolutionary for the food industry as they can make foods brighter, enhance their flavor and keep foods fresh longer. Nanoparticles made from silver can suppress the growth of dangerous organisms and are being used by farmers.

What Are Nanoparticles?

Nanoparticles are microscopic particles less than 100 nanometers in size. Actually, calling them “microscopic” might be an overstatement as one nanometer is equal to one billionth of a meter. They’re created by breaking down much larger substances (by subjecting them to high heat, for instance) and have multiple biomedical, optical and electronic applications.

Nanoparticles made from grapefruit-derived lipids (molecules including fats and some vitamins) are being used to reduce the adverse effects of drug treatments such as chemotherapy. Nanoparticles made from gold have been used for centuries by artists (in the Medieval and Renaissance period) to produce vibrant colors and are now being investigated by scientists to use as therapeutic agents and electronics. Clay nanoparticles are used to create stronger plastics.

These tiny, tiny particles have stoked great scientific interest because they can be a between bridge bulk materials and atomic or molecular structures.

Are There Risks in Ingesting Nanoparticles?

While nanoparticles made from silver are currently being incorporated into food and clothing to eliminate bacteria and odors, the health risks to humans and potential damage to the environment posed by them have yet to be fully studied. Scientists at the University of Missouri College of Agriculture, Food and Natural Resources have now found a reliable method to detect silver nanoparticles in fresh produce and other food; their findings suggest why we should be concerned about the pervasiveness of nanoparticles.

Scientist Mengshi Lin and his colleagues tested the extent to which silver nanoparticles remain as a residue on and even penetrate into the pulp of fresh fruit. They immersed the pears in a nanosilver solution that is similar to a pesticide application and repeatedly washed and rinsed them. After four days, the nanoparticles remained attached to the skin of the pears and had also become embedded into their pulp.

“The penetration of silver nanoparticles is dangerous to consumers because they have the ability to relocate in the human body after digestion. Therefore, smaller nanoparticles may be more harmful to consumers than larger counterparts,” says Lin.

Nanoparticles are used in more and more products. Currently, the Environmental Protection Agency has given silver nanoparticles a “conditional” registration but without putting them through the full range of required tests,” to the concern of scientists and consumer and environmental advocates.”