Small Particles, Nanotechnology and Food

About the term Nanometre

The term nanometre refers to a measure of distance that is very small.   A nanometre (nm) is one thousand millionth of a metre (10^-9 of a metre) - this is w ell beyond what the human eye can see even through a microscope.   A human hair or the thickness of a piece of paper, is around 100,000 nanometres.   On a relative scale, if a marble was one nanometre in diameter, a metre would be the size of the earth!

The terms ‘nanoparticle’ or ‘ultra fine particle’ refers to extremely small particles of matter in the nanometre scale. The term nanotechnology can also be applied to emulsions (nano-emulsions) and tiny capsules (nano-capsules).

What is Nanotechnology?

While there is no internationally agreed definition for ‘nanotechnology’, the term is usually applied to the process of controlling the size and shape of materials at the atomic and molecular scale.  Generally, the term applies to deliberately engineered matter less than 100 nanometres (nm) in size in one dimension. At this size, particles are much smaller than human cells and even bacteria and viruses.

Is Nanotechnology new?

No.   The term ‘nanotechnology’ has become more widely used in recent years but developments in a variety of scientific fields have been going on for decades.   Developments across fields such as; physics, materials science, surface and colloid chemistry, chemical biological and electrical engineering have all contributed.   Advances in scientific instrumentation have also enabled the imaging and manipulation of matter at the nanometre scale.

Is Nanotechnology only relevant to food?

No.   Nanotechnology holds most promising applications in other fields such as medicine, electronics, materials science and solar energy.   Within Australia, the emergence of commercial applications for nanotechnology is being monitored by several Australian Government agencies.   FSANZ is one agency working within the whole of government framework.   An Inter-Departmental Committee led by the Department of Innovation, Industry, Science and Research has been convened to coordinate a national approach to nanotechnology.   FSANZ is also an active participant in a Health, Safety and Environment Working Group under the Inter-Departmental Committee that is examining issues such as the possible toxicity risks for human health and the environment.

Is consumption of small particles new?

No.   Food and drinking water naturally comprises particles in the nanometre scale.   Throughout their existence, humans have been exposed to ultrafine and nanometre scale particles such as; smoke, dust, ash, and fine clays through the air, food and water.   Humans inhale and ingest many millions of organic and inorganic nanoscale particles every day in their food and drinking water and it is estimated that people inhale around 10 million nanometre scale particles in every breath.   Many ancient cultures, as well as animals, have deliberately sought and consumed fine clays of volcanic origin to remove the naturally occurring toxins from   food and water.

Food consists of small particles of matter.   Generally, proteins in foods are globular structures 1-10 nanometres (nm) in size and the majority of polysaccharides (carbohydrates) and lipids (fats) are linear polymers with thicknesses in the nanometre range.

Milk is an example of an emulsion of fine fat droplets of nanoscale proportions.   Traditional processing of milk such as pasteurisation and curdling is known to change the size of particles reducing them in size or causing them to agglomerate (join together into larger particles).

Are smaller particles in food unsafe?

The human body is well adapted to dealing with a wide range of foods and contaminants of highly variable composition.   The gastrointestinal tract is equipped to break down and dissolve foods as much as possible in order to absorb the nutrients and derive the energy necessary to run our bodies and sustain life.   Acids and enzymes present in our mouth and stomach play a significant role in the digestive process and generally, the more food is able to be broken down and dissolved, the more nutrients are able to be absorbed by our bodies.

FSANZ recognises that very small particles of matter can behave differently to larger particles of even the same matter and that care does need to be taken to ensure that small particles in food are just as safe as larger particles.   The size of particles in food however, is only one of a number of considerations relevant to ensuring the safety of food.   When FSANZ assesses the safety of foods or food ingredients, it examines a wide range of scientific evidence that establishes that it is safe to consume.

How can Nanotechnology be used in food?

Traditional foods already incorporate nanoscale particles, however advances in the field of nanotechnology are very likely to give rise to other applications in food.   For example, nanotechnology could be used to produce cheap and highly effective filters to eliminate contaminants and bacteria from water for drinking.   This would be of enormous benefit to millions of people who do not have reliable access to safe drinking water.   Food packaging could also be developed utilising nanotechnology to absorb oxygen in the air that enters the package in order to help prevent harmful bacteria growing in the food.

Are Nanotechnology foods available in Australia?

Aside from traditional foods containing nanoscale particles, FSANZ is not aware of any food sold in Australia that contains any new type of engineered nanoscale particles .   FSANZ will continue to gather information from all relevant sources, particularly other Australian Government agencies, industry, non-government organisations and our regulatory partner agencies around the world.

Are there regulations to ensure foods using Nanotechnology are safe?

All food supplied in Australia must comply with the Australia New Zealand Food Standards Code (the Code) and be safe for human consumption.   A number of types of foods and substances added to food, such as processing aids and additives, require premarket approval before they can legally be supplied. Premarket approval involves a rigorous safety assessment using the best available scientific evidence as it applies to Australian circumstances.   There are also mandatory upper limits set for contaminants such as heavy metals and residues of agricultural and veterinary residues in food.

The Code also sets out the requirements for labelling foods in Australia and New Zealand.   The purpose of standards for food labels is to provide information to consumers that allow them to make informed choices. The Code is enforced in Australia by the state and territory governments and in New Zealand by the New Zealand Food Safety Authority (NZFSA), The Australian Quarantine and Inspection Service (AQIS) enforces the Code for imported foods.

If FSANZ receives an application for a new type of engineered nanoscale particle in food, it would be assessed depending on the type of substance or food eg; whether it is a processing aid, food additive, novel food or novel food ingredient.   The premarket requirements of the novel food standard apply to non traditional foods where an assessment of the public health and safety considerations is required having regard to –

• the potential for adverse effects in humans; or
• the composition or structure of the food; or
• the process by which the food has been prepared; or
• the source from which it is derived; or patterns and levels of consumption of the food; or
• any other relevant matters.

The key issue is whether there is any added risk to human health and safety due to the characteristics of newly engineered nanoscale particles used in food.

FSANZ will monitor research developments related to nanotechnology and food safety occurring around the world on an ongoing basis.   FSANZ will continue to ensure the safety of food is rigorously assessed through the application of the current provisions of the Code and will make adjustments to the regulatory framework should it become necessary.

What else is FSANZ doing about Nanotechnology?

As with most developed countries, FSANZ is currently gathering information from all available scientific sources and has established comprehensive networks and contacts for exchange of information on the use of nanotechnology with our regulatory colleagues both within Australia and internationally.

FSANZ has appointed a senior project manager and set up an in-house steering group to keep abreast of nanotechnology developments and respond to the situation appropriately.

FSANZ has extensive linkages with international organisations and regulatory agencies and is also collaborating with the Food and Agricultural Organisation of the United Nations and the World Health Organisation (FAO/WHO) to facilitate a joint FAO/WHO ‘International Meeting on Food Safety Implications of Nanotechnology Applications in the Food and Agriculture Sectors’ to be held in 2009.   FSANZ is also participating in other international activities through the Organisation for Economic Co-operation and Development (OECD), the Codex Alimentarius Commission (CODEX) and the Quadrilateral Countries (Australia, New Zealand, Canada and the United States of America).