Updated: Oct 23, 2021
The application of Nanotechnology has a wide array of uses through many industries. The emerging and growth in Nutritional Science are rapidly and widely used in food production and supplementation.
It is also widely being utilized in parts of medicine and science. Especially in regard to nanoparticles for diagnostic and screening purposes in cancer detection, the development of artificial cellular proteins such as receptors; DNA and protein sequencing using nanopores and nanosprays; and the manufacturing of unique drugs and nutrient delivery systems; as well, as gene therapy and tissue engineering applications.  Nanotechnology is being employed today to assist with combating COVID-19, through nanospray applications to disinfect and sanitize hospitals, schools, and train systems, and other hard surfaces. Its unique size, at the scale of ~1–100 nm (nano-micron), provides a wide range of applications at the microscopic level.
A nano-micron probably seems improbable to imagine. While a micron, also called a micrometer, is 1/1,000,000th or one-millionth of a meter. About 40-50 microns make up the diameter of a single strand of hair.
A nanometer or nano-micron is 1,000 times smaller than a micrometer. Furthermore, an atom is smaller than a nanometer. Nanotechnology or a more apt descriptive is Molecular nanotechnology, since the manipulation of matter, is at the scale of atomic, molecular, and supramolecular. The manipulation of individual atoms and molecules at the dimensions and tolerances of less than 100 nanometers. Its application in nutritional science is varied and diverse. Some of its uses are the modification of taste, color, and texture of food. The technology is also used in the detection of food pathogens and spoilage microorganisms, because of this it is widely utilized in the production and preservation of packaged foods. It can also enhance the nutritional quality of foods, and thereby assist with nutrient delivery, this is available in supplementation.
Nanotechnology's use in food technology application is primarily involved with the creation of coatings for foods and food packaging that serve as barriers to bacteria or can contain additional nutrients.  As mentioned earlier, it's used to prevent spoilage and rancidity in the preservation of shelved packaged food helps extend the shelf life of foods. This can increase and extend the amount of time before food spoilage.
This aspect of nanotechnology may allow the possibility of healthy food to reach more individuals and diminish the concerns around spoilage. It can also improve the health of individuals and can aid in reducing the problem of food shortage. However, there are significant concerns around nanotechnology applications in food products and nutritional health.
The level of toxicity due to the change in size and highly reactive nature of nanoparticles are concerns related to nanotechnology in nutrition and food production. Nanoparticles are highly reactive because they have a larger surface-area-to-volume ratio. This means that nanoparticles have higher energy and therefore are more unstable. The benefits conferred from applications of nanotechnology in food production, preservation, and supplementation, versus the potentiality of toxicity are important concerns.
Nanoparticles in nutrition and food products are either organic or inorganic materials. The difference between the two determines their metabolization by the gastrointestinal system. In turn, this distinction can impact the possible level of toxicity from nanoparticle presence in food products. The concern of inorganic nanoparticle material is the accumulation, in tissues, leading to toxicity.
A significant amount of inorganic nanoparticles (NPs) contain heavy metals. Accumulation of heavy metals from NPs is a particular concern around its uses in food and supplementation. A common nanoparticle of particular concern is the use of silver, also known as nanosilver. Since nanosilver is readily used for its antibacterial uses. The toxicity of silver is both an ingestion and environmental concern.
Biological concerns are related to the interaction of macromolecules and surface oxidation which are due to the release of silver ions, however, the difficulty is in distinguishing which portion of the toxicity is from the ionic form or nano-form of silver.  In short, the use of inorganic particles may present a biological interaction concern, as they may disrupt normal and optimal cellular processes, and may even increase adverse pro-inflammatory effects such as Oxidative Stress, ROS proliferation, and the disruption and altering of cellular protein and nucleic acids.
Therefore, the question of the toxicity of inorganic nanoparticles is a significant concern. Since the accumulation of inorganic particles like nanosilver may lead to such conditions as argyria or argyrosis, which is the accumulation of silver in mucous membranes, often giving individuals a bluish skin tint, often the result of misuse of colloidal silver consumption.
Nanoparticle technology advances and uses are increasing across multiple industries. The United States has led indirect funding associated with Nanotechnology applications, with the National Nanotechnology Initiative—the coordinating body for American nanotechnology research—having a proposed budget of over $1.5 billion in 2009, up from under $500 million in 2001. 
Nanotechnology offers many advantages and can offer meaningful and exciting advances in antibacterial applications, prevention of food spoilage, and extending the shelf life of food, which can offer some solutions to global hunger and food security-related issues. However, concerns around toxicity and the possible disruption of both organic and inorganic nanoparticles at the cellular level are one worth further study.
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