Nanotechnology

January 2019

Nanoscience and nanotechnology are about understanding and exploiting materials at the atomic and molecular level. Materials at the nanoscale have been shown to have markedly different properties to those at the macroscale, which means that nanomaterials offer exciting new benefits to many applications including food.

There are very many applications using nanotechnologies including: electronics, sensors, pharmaceutical and drug products, aerospace industry, home goods, building materials, sports goods and many more. To date, however, only a small percentage of applications are in the food arena, mainly concerned with food and nutritional supplements, and packaging.

The content of this IFST Information Statement defines, and briefly explains, nanoscience and nanotechnology, assessing the potential applications and public concerns, their use in food, and outlining the safety, risk and food regulations in this area.

The main food application areas considered to potentially benefit from nanotechnology are:

  • agriculture
  • food packaging
  • food supplements
  • food processing

Examples already using nanotechnology include smart or intelligent packaging, which can slow down product deterioration, or alert consumers or retailers, when the product is not safe or of good quality. ‘Nano’ forms of nutrients or vitamins act much faster in the body than conventional forms, so nano-calcium or iron fortification is available, usually in a drink format. Using the same principle, nano-pesticides or nutrients can be used in agricultural applications to benefit crops. All foods contain nanostructures which are developed naturally or as part of the processing. Examples of these include powdered ingredients, part of which will be in the nanoparticle size range, interfacial membranes and material stabilising foams and emulsions. Controlling these structures allows improvements in product properties.

With benefits also come some risks and concerns. The current regulatory landscape is presented as well as brief summaries of reports carried out assessing risks and benefits. Finally, a comprehensive reading list is included.

Introduction

Nanoscience and nanotechnology are about understanding and exploiting materials at the atomic and molecular level. Nanoscience is now an established science, taught in schools and universities, and is a key technology in a wide variety of applications. So why should the study and manipulation of materials at such a small scale be, to paraphrase Lord Sainsbury, ‘big news’? The answer is that materials at the nanoscale have been shown to have markedly different properties to those at the macroscale. This means that, by controlling the manufacture of products at the nanoscale, there is the promise of the production of materials with new, exciting properties, tailored to the needs of industry, including the food industry.

It has been estimated that the global market for nanomaterials had a value of $23 billion in 2014. The market in nanomaterials and nanotechnologies is now so large that forecasts are given for areas of applications rather than just nanotechnologies, for example nanofilters, nanocomposites and quantum dots. The markets for these are all expected to be in the billions or trillions of dollars by 2018 to 2020. There are very many applications, using nanotechnologies, covering electronics, sensors, pharmaceuticals and drug products, the aerospace industry, home goods, building materials, sports goods and many more. However, to date, only a small percentage of applications are in the food arena, mainly concerned with food and nutritional supplements and packaging. Nanotechnology, however, has already provoked public concern, and debate, and such discussions are particularly sensitive for food related applications. There are equally vociferous proponents and opponents of this new, emerging technology. It is therefore opportune to address the question of what impact nanotechnology will make, and how it will affect the food industry. The intention of this IFST Information Statement is to define and briefly explain nanoscience and nanotechnology, to assess the potential applications and public concerns about their use in food, and to outline the present and potential attitudes to safety, risk and food regulations in this area.

Nanoscience and nanotechnology

What exactly are nanoscience and nanotechnology? Nanoscience is defined as the study of phenomena and the manipulation of materials at the atomic, molecular and macromolecular scales, where properties differ significantly from those at a larger scale. The recognition that the properties of materials change significantly at the nanoscale, due to quantum effects, is important and emphasises the need to consider size in the assessment of risk-benefits of the use of these materials in food and food-related products. Nanotechnology involves the design, production and application of structures, devices and systems, by controlling the shape and size at the nanometre scale.

The term ‘nano’ is derived from the Greek word for dwarf. To put things in perspective, a nanometre (nm) is one-billionth of a metre, or approximately one hundred thousandth of the width of a human hair. Nanoscience and nanotechnology are generally concerned with materials with dimensions in the range of 1 to 100 nm in size, in any one dimension. This definition is still a matter for debate, especially around structures made from nanoparticles that have been aggregated together to form larger particles. Thus, nanoscience and nanotechnology are about understanding and engineering materials at the molecular or atomic level. Richard Feynman, the Nobel prize winner for physics in 1965, was one of the first to recognise the potential for new properties at the ‘nano’ level and introduced the concept with his talk entitled ‘There is plenty of room at the bottom - an invitation to enter a new world of physics’.

The significance of this is that when the particle size is very small, it can lead to fundamental changes in properties of the material or element. Most people will be familiar with the opaque nature of the filler particles of titanium dioxide, generally used as an intense white pigment. However, nanoparticles of titanium dioxide are transparent, suggesting novel uses in transparent sunscreens, food packaging or plastic food containers. Silver nanoparticles can be incorporated into bandages and provide an antibacterial function, whereas larger silver particles are far less effective. Carbon is mainly a soft material but when organised in nanotubes, becomes extremely hard.

Why should this be the case? Surely the properties of materials are set by the properties of the atoms or molecules? We now know that this is not always the case. The nanoscale structures have very different properties. An example given is that a 1mm cube of sand would very slowly dissolve in water over the period of millions of years. On the other hand, a cube of 1nm would dissolve in about 1 second. One reason the properties are different, when particles are very small, is due to the surface area to volume ratio. In a cube of 1cm, approximately 1 in 10 million atoms are on the surface. In a cube of 1nm however, 80 in 100 are surface atoms. The surface properties dominate in the nanomaterial. Examples of the use of these special properties can be found in nature, with the formation of colour on some butterfly wings due to the arrangement of scales of chitin to form structures called gyroids. These are very narrowly spaced which causes the light to move through them in a complicated way producing colour.

Nanotechnology is here to stay, and already forms the basis of a number of commercially available non-food products. Examples of non-food applications using nanotechnology include pharmaceutical products, automobile paints, transparent sunscreens, stain- and water-repellent clothing, improved sports equipment, self-cleaning glass, paving slabs and concrete. Further details and examples can be found at: http://www.UnderstandingNano.com

Potential food related applications

There have been many questions regarding the potential and the suitability for nanotechnology in foods. Since there are obvious benefits of nanotechnology in other areas it is inevitable that food companies are interested in potential benefits of new technologies in food applications.  Kraft Foods started the first nanotechnology laboratory in 1999 and its ‘Nanotek’ consortium, involving 15 universities worldwide and national research laboratories, was established in 2000. One of the areas considered to be open to the benefits of nanotechnology was the development of smart filters which could selectively remove allergens making foods safer. Additionally, filters to remove contaminants would allow the extension of shelf life for cooking oils, for example. Since then there have been developments in food applications, mainly on the packaging side, but also in enhanced nutrition. The main areas, for nanotechnology to potentially benefit food, are considered to be:

  • agriculture
  • packaging
  • supplements
  • processing.

A good overview of benefits can be found in ‘Nanotechnology in Food’ https://www.nanowerk.com/nanotechnology-in-food.php. In recent reviews on the applications of nanotechnology in foods, Pathakoti et al 2017[1] and Singh et al 2017[2] list areas of research which include packaging, food safety, food nutrition and processing.

 

 
Food Packaging

With regard to packaging, there are many ways that nanotechnology can benefit the industry and the consumer, hence this is an area that has developed more than others. Packaging protects food from physical damage but also from chemical and microbial spoilage, as much as possible. ‘Use by’ and ‘Best before’ dates are selected based on real time shelf life studies where the growth of organisms is monitored, and the chemical changes leading to unwanted quality changes, such as rancidity, are also checked. These dates are chosen to ensure that the food product is safe, with a margin for error or variability due to the environmental conditions. Using smart packaging, the real in-product changes can be detected and, in some cases, slowed down.

Smart packaging includes active and intelligent packaging. Active packaging works to slow down oxidation or moisture changes in the product increasing shelf life. Examples of active packaging include plastic beer bottles or juice packaging with nanoclay incorporated into the plastic to slow down oxygen transfer, and nano-silver to prevent microbial growth.

Intelligent packaging tells the consumer or retailer when the product is no longer safe or useable, as well as potentially many other useful areas of information through interaction with the internet. Examples of intelligent packaging include labels that turn red when the product has started to spoil as well as QR codes that provide selected information to mobile phones.

Food Supplements

Adding nutraceuticals such as vitamins, calcium, iron etc to foods to benefit consumers has been used for many years. Using nanotechnology to create nano-encapsulated nutrients such as vitamins, or nano-sized calcium or iron allows them to be added to drinks with no effects on clarity or visual appeal. Additionally, and importantly, they are absorbed faster in the body when in the nano state. Examples of the use of nanotechnology, in this area, includes many variants of nano-calcium, nano-magnesium and nano-iron.

Agriculture

Nanotechnology can provide benefits in growing crops and farming animals. These are reviewed by Fraceto et al (2016)[3] who describe four main areas that are potentially of benefit:

  • Productivity increases by using nano-pesticides and fertilisers
  • Soil improvement using nanoclays and gels
  • Plant growth increases by using nanomaterials
  • Environmental monitoring using smart sensors

Using these techniques is at an early stage but it is considered important that they are developed further to cope with the growth in population and increased food and water demands.

 

Nanostructures in food and food processing

Many food scientists would claim that they already embrace nanotechnology. Food proteins are globular particles with dimensions in the size range of 1 to 100 nm, i.e. true nanoparticles. Many polysaccharides (carbohydrates) and lipids (fats) are linear polymers, less than 1 nm in thickness i.e. 1- dimensional nanostructures. Setting jellies, keeping particles suspended in dispersions and preventing emulsions from separating into distinct oil and water phases, involves creating molecular networks, including both 2- and 3-dimensional nanostructures. When starch is boiled to make custard, small 3D crystalline structures, only tens of nanometres in thickness are melted. How thick the mixture becomes, or whether it sets to a gel as it cools, depends on the assembly and re-crystallisation (retrogradation) of the nanostructures formed by the starch polysaccharides.

Understanding the nature of nanostructures in food and how they form from the ingredients and manufacturing processes allows better selection of raw materials and enhanced food quality through processing. Although there are many studies on the relationship between food microstructure and properties such as texture, flavour and stability, it is very much an area that needs further study. What is lacking is detailed information, and as a result the selection of ingredients and processing operations are still largely empirical.

Microscopic methods developed to probe the nanoworld, such as the electron microscope (EM) and atomic force microscope (AFM), allow us to look at these complex systems and understand their behaviour and have proved particularly useful for probing molecular structures in food[4]. Such knowledge permits understanding of the mechanisms involved in the formation of food nanostructures and underpins the ability to rationally design food nanostructures to achieve desired functionality

A good example of the power of nanoscience is how it has improved the ability to control the quality of foams and emulsions. Creation of foams (e.g. the head on a glass of beer) or emulsions (sauces, creams, yoghurts, butter, margarine) requires the generation of gas bubbles, or droplets of fat or oil, in a liquid medium. This involves producing an air-water or oil-water interface, and the molecules present at this interface determine its stability. These structures are 1 molecule thick and are examples of nanostructures. A source of instability in many such foods is the breakdown or aggregation of this interface. Instabilities lead to the foam collapsing or the emulsion separating into oil and water layers. Proteins and surfactants naturally self-assemble at interfaces. By controlling the types of materials that reach and assemble at the interface, it is possible to build interfacial structures and control their functional properties. This is really nanotechnology, but the processing tools are familiar and conventional. Nanoscience provides the knowledge to allow rational choice of materials and for traditional processing methods to be optimised to deliver desired functionality.

Nanoscience allows the examination of the molecular components of foods and the molecular structure of foods. It shows why food materials behave in the way they do. An example of applying nanotechnology in foods is seen in the development of double emulsions to reduce the level of fat in dressings and mayonnaise. A typical mayonnaise will have about 80% oil present as small micron-sized oil droplets in water. Reducing the level of oil to about 40% produces separation of the oil and water, so to prevent this, a stabiliser needs to be added to the water phase. Typically, this is modified starch or a similar hydrocolloid that will thicken and bind the water. Using nanoscience and standard emulsification methods, an alternative way to lower the level of oil without the use of further additives is to produce a multiple emulsion, usually a double emulsion. This would be a water in oil in water emulsion for dressings and mayonnaise, known as a WOW emulsion. The water is partitioned so that some is incorporated into the oil droplets as a very fine emulsion where the droplets are often below 100nm. This reduces the water content of the continuous phase making it stable to the lower oil content. Figure 1 shows a schematic of this change in structure, and Figure 2 shows a standard emulsion compared to a WOW emulsion.

Figure 1: Schematic of standard mayonnaise emulsion (LHS); reduced fat mayonnaise (centre) and WOW (RHS). Oil id red water blue

Figure 2: Confocal microscopy images of standard emulsion (LHS) and WOW (RHS)

 

 

 

 

 

 

 

Potential concerns about nanotechnology

Making materials smaller, or building up materials atom by atom, can generate novel and useful properties as described above. However, there are some concerns about nanotechnology and the unknown properties of nanoparticles. In particular there are concerns that certain nanoparticles are potentially toxic to the environment or to human or animal health.

Examples of these concerns are the use of nano silver as an antibacterial coating in household goods such as washing machines, dishwashers, plastic food containers etc. Additionally, the potential for nano silica or nano titanium dioxide, allegedly present in the nano form in certain foods containing these ingredients, to be absorbed into the body through the calcium uptake mechanism has given rise to concerns and research into potentially harmful effects on human health. In a limited study on nano silver impregnated into plastic food containers no evidence of migration of the silver into the food was found, suggesting that it is safe to use these products.

Titanium dioxide is an approved food colour (E171) with a ‘non-specified’ Acceptable Daily Intake (ADI). TiO2 is widely used as a white pigment primarily in surface coatings. In terms of food packaging, TiO2 is used as a filler particle in paper and increasingly in plastics and building materials or sunscreens as nanoparticles of TiO2 are transparent but retain their resistance to UV radiation. This has led to their use in coatings on glass and in sunscreens and lotions where they are of great benefit and no or little toxicity. The Scientific Committee on Cosmetics and Non-Food Products (SCCNFP) considered the use of TiOas a UV filter and declared it safe at any size. The pigment is also used directly within foods, for example in confectionery products such as sugar coatings, where it is used to produce a pure white base onto which other colours can be added, thus enhancing the clarity of their colour, or as a clouding agent in dry beverage mixes. However, the limited toxicity data available on animals and humans suggest that such materials will not penetrate beneath the epidermis.

An interesting situation arises in materials such as SiO2, which are present in certain vegetables but is also an allowed food additive (E551) used as an anti-caking agent. The preparations of SiO2 are not monodisperse but polydisperse containing pENMs (persistent engineered nanomaterials) a fraction of particles that are nano-sized. Most suggested definitions of pENMs take into account this type of polydispersity and, in addition to defining a size range (usually 1–100nm), they suggest that if more than 1% of the number size distribution contains particles in this size range they need to be classified as pENMs. Irrespective of whether commercial SiO2 preparations should be classified as pENMs, and hence could become subject to future re-testing and possible labelling as ENMs (engineered nanomaterials), it is suggested that their use will result in the ingestion of SiO2 nanoparticles. The mode of uptake, distribution, possible accumulation and toxicity of these particles is unknown. Recent toxicology studies have not demonstrated any harmful effects (http://www.efsa.europa.eu/en/efsajournal/pub/5088).

To date, no firm evidence has been found for these harmful effects, but it is wise to be cautious where certain nanoparticles are concerned. In the general use of nanoparticles, it is important to assess how products of nanotechnology and their manufacture may eventually lead to the release of particulate nanomaterials into the environment, and to estimate the subsequent levels of exposure to these materials. The extent to which these materials can enter to the human body, the sites of penetration and possible accumulation of these materials will ultimately determine the possible risks of exposure, particularly for nanomaterials that cannot be metabolized within our bodies.

Globally, there is pressure to produce an  an enforceable definition of 'nano' that can be used to regulate the use, approval and possible labelling of nanotechnology products. A number of reviews and reports have suggested the concept of ‘engineered nanomaterials’ (ENMs) as the nanotechnology products that require definition and regulation. These definitions are intended to be generic and not designed specifically for food materials. The use of the term nanomaterials is important for the food industry because materials are, by definition, composed of structures formed from atoms or molecules: this definition would implicitly exclude natural food biopolymers such as carbohydrates, proteins and lipids. The term engineered is generally taken to mean processed or manufactured and thus, because many of these biomolecules are produced commercially, and have one dimension in the nanoscale range, they would be included in the broader term ‘engineered nanoparticles’.

The current proposed definitions of nanomaterials include, as a category, what might be termed persistent engineered nanomaterials. The exclusive use of the term pENMs would exclude the natural self-assembled nanostructures present in native food materials (e.g. plant cell wall material, fibres in meat and fish, or starch) and presumably the nanostructures induced in processed food systems.  There is still debate as to whether a definition of nanomaterials should include additional qualifications relating to the characterization of internal nanostructures, or measurements of surface to volume ratios designed to capture applications that use aggregates, agglomerates or composites containing particulate nanomaterials. A consequence of the inclusion of such terms would mean that the term nanomaterials would include most natural or processed food materials, for which the characterization of the internal nanostructures would be difficult if not impossible. This would then require specific exemptions for these food materials.

There is also an awareness of the need to distinguish between two types of pENMs, those that are metabolised within the body, and persistent pENMs, that are not broken down and may accumulate within the body. The latter group is suggested to be those that require special attention and would include silver, titanium dioxide and silicon dioxide.

Scientists and technologists have a responsibility to ensure the safety of the products that they develop. Consumers are entitled to expect any changes in food composition or packaging materials that involve nanotechnology to be necessary and safe, the appropriate toxicity testing to have been done and the results to be freely available in the public domain. The idea that size can alter toxicity is not unprecedented in the food industry. There has been published work that suggested that low molecular weight carrageenan may be harmful. This led to concerns about the presence of low molecular weight material in carrageenan used in the food industry.

The present position of the FDA on nanotechnology in food recognises the importance of particles size, and the need for collection of information on the properties and potential toxicity of ENMs. In 2007, the FDA published the results of a Task Force on nanotechnology. Following recommendations from this Task Force, the agency issued (June 2011) a draft guidance for industry, intended to enable industry to determine whether a FDA-regulated product involves the application of nanotechnology. A recent draft guideline (April 2012) contains information, which is intended to alert manufacturers to factors they should consider when determining whether a significant change in a manufacturing process, such as nanotechnology, for a food substance already in the market will:

  •  affect the identity of the food substance
  •  affect the safety of the use of the food substance
  •  affect the regulatory status of the use of the food substance
  •  require a new regulatory submission to FDA

Access to the current and evolving FDA guidelines on the regulation and use of nanotechnology and ENMs in food and food contact materials is available through the FDA homepage: http://www.fda.gov/ScienceResearch/SpecialTopics/Nanotechnology/ [5]

Government reports on nanotechnology

The House of Lords Science and Technology Committee inquired into the use of nanotechnologies in the food sector. Their first report ‘Nanotechnologies and Food’ was published in January 2010 (http://www.publications.parliament.uk/pa/ld200910/ldselect/ldsctech/22/22i.pdf [6]). They recognised that there were potential benefits from nanotechnologies as well as potential risks. The number of food products containing nanomaterials was small, but the expectation was that this was likely to increase in the future as the technology developed. They made a number of recommendations intended to support responsible development of nanotechnologies in the food sector and to ensure that potential benefits to consumers and society are supported, where appropriate, by Government. These are listed on the FSA website and information related to the FSA response to these recommendations can be obtained from their website at http://www.food.gov.uk/policy-advice/nano/ [7]

Regulatory control

It is now recognised that size is important and that the properties of nanomaterials can differ considerably from those of the macroscopic form of the material. Hence the safety guidelines and evaluation procedures used for the macroscopic form may not be adequate for assessment of the equivalent nanomaterials. In the absence of a complete picture of the food safety and potential toxicological properties of individual types of nanomaterials, and at this early stage in the development of the technology, it seems to be appropriate to regard nanomaterials as a separate class of either “novel foods” or new additives for food and / or food packaging use, and to control them under one of the respective regulatory frameworks, accordingly.

Dependent on the nature and proposed use of the nanoparticles, it may be an appropriate condition of the authorisation to require a specific post-market monitoring scheme (again, on a case-by-case basis). Furthermore, should the initial assessment indicate that particular consumer groups may be subject to additional risk, specific advisory labelling may also be required (as is currently the case for phytosterols) in addition to the general requirements proposed below.

The Food and Agricultural Organisation (FAO) of the United Nations and the World Health Organisation (WHO) convened an expert meeting on the potential safety aspects of the application of nanotechnologies in the food and agricultural sectors in June 2009. The key findings, conclusions and recommendations of the meeting were published in 2010 http://www.fao.org/docrep/012/i1434e/i1434e00.pdf [8]. Following the expert meeting, the FAO/WHO commissioned a report summarising and analysing the information that has since become available, and determining the possible courses of action that should be followed by the FAO and WHO. The report entitled ‘State of the art on the initiatives and activities relevant to risk assessment and risk management of nanotechnologies in the food and agriculture sectors’ collected information on the actual and proposed uses of nanomaterials resulting in human exposure through food or food contact materials since 2009. It reviewed national and international activities on the risk analysis of nanomaterials in the food and agricultural sectors carried out since 2009 (https://doi.org/10.1016/j.foodres.2014.03.022).

Novel foods and food ingredients

The safety of novel foods and food ingredients is already regulated by the EU Novel Foods Regulation 258/97. Under the provisions of Regulation (EU) No. 2015/2283 on novel foods, engineered nanomaterials are considered a novel food. The definition is in line with that of Regulation (EU) No.1169/2011 for consistency purposes. The difficulty is that a definition, of the form under consideration within the EU, and based purely on size, would not distinguish between what might be termed ‘low risk nanomaterials’ that are fully digested within the body and what might be termed ‘potentially high risk persistent nanomaterials’. It might therefore be necessary to consider exemptions for certain ‘low risk’ products, possibly following a tiered assessment, based on the past use and digestibility of the components of the application.

Food additive use

Nanoparticles intended for direct food additive use, such as TiO2, should be considered under the framework of Directive 89/107 and be assessed either as novel additives or, in the case where the macro-material is already approved, through potential amendments of the appropriate purity criteria (Directive 96/77/EC). The definition of a nanomaterial could have implication for the use of materials such as SiO2 or TiO2, depending on the level of particles in the nanoscale range in the preparations, and thus the need for labelling or additional safety assessment of the nanoforms. An alternative would be to eliminate the fraction in the nanoscale range.

Packaging and other food contact materials

Nanoparticles are already sold for use in food packaging and containers. The use of nanoparticles in food contact materials should be assessed within Regulation 1934/2004. This applies to all materials which are intended to come into contact with foodstuffs such as all types of packaging, bottles (plastic and glass), cutlery, domestic appliances and even adhesives and inks for printing labels. It provides for the establishment of a positive list of authorised substances, within specific legislation for each type of food contact material and requires that new substances for food contact use must be authorised, following consideration by EFSA in respect of their potential toxicity. Furthermore, this Regulation also establishes requirements relating to the traceability of food contact materials from production to sale. Regulation (EC) No. 450/2009 on Active and Intelligent Materials and Articles requires a risk assessment of nanoparticles in intelligent packaging systems. Currently received and valid applications are kept in a Register which is published by the European Commission. In accordance with Regulation (EU) No. 10/2011 on Plastic Food Contact Materials substances in nanoform can only be used if the nanoform is authorised and listed in the specifications of Annex I of the regulation. Currently the only ‘nanoparticle’ in Annex I is titanium nitride for use as additive or polymer production aid. In addition, carbon black and amorphous silicon dioxide are listed without being specifically named as “nanoparticle”, but with size ranges specified, which are below or around 100 nm.

EU regulation 1169/2011 is designed to inform consumers of the presence of engineered nanomaterials in food. It is clearly important that the definitions adopted, which may lead to enforced labelling, are restricted to ‘potentially high risk’ nanomaterials or that exemptions to labelling can be made for low risk nanomaterials. Labelling may lead to a barrier to the use of nanotechnology in the food sector. Whilst the interpretation of this requirement is necessarily subjective, this also suggests that there is a strong argument that, where an ingredient is in nanoparticle form, its name in the ingredient list should be qualified accordingly.

Conclusions

It seems clear that nanotechnology will have both direct and indirect impacts on the food industry. Most of the anticipated impacts are likely to enhance the choice and quality of foods and, in most of these applications, there would appear to be negligible safety concern.

Although nanotechnology will contribute to these enhancements, it is unlikely that its use will be advertised prominently or explicitly and, hence, it is unlikely to provoke direct interest or concern. However, if the impacts are associated in consumers’ minds with nanotechnology, then we do not, as yet, have sufficient evidence from social science-based studies to show whether they will be well received.

Nevertheless, as with any relatively new technology, there will be fears by some and problems, actual or speculative. It is, therefore, important to assess public understanding, reaction and potential concerns over the use of nanotechnology and, in the event that such concerns are identified, it will be important that any use of nanotechnology addresses them. There will be the need for risk assessments, and for appropriate regulatory controls to be introduced.

Most concern potentially centres around the possible ingestion of free persistent particulate engineered nanomaterials, where there is a lack of knowledge on whether the reduced size may, in some cases, lead to an increase in toxicity. This is partly because the small size of these particles may allow them to reach regions within cells or tissue that normal macroscopic particles of the same composition could not reach. Hence, the conventional toxicity tests may be inadequate and there may be special issues related to bio-accumulation of nanoparticles.

It is essential that the use of nanotechnology in the food industry should be, and should be seen to be, necessary and to enhance the safety and quality of foods.

The consumer should therefore be consulted about the use of nanotechnology in food and should be able to exercise choice when purchasing foods that have been produced and packaged with the use of this technology. Identifying the use of such particles, where they are used in foods, would facilitate consumer choice and when foods containing authorised, free persistent nanoparticles are placed on the market, the label should indicate that fact.

The detailed definition of engineered nanomaterials (ENMs) adopted by the EU and internationally will be important for the food industry. The best solution would be a focus on persistent engineered nanomaterials. If labelling is mandatory for all products falling within this definition, then the use of a tiered risk assessment processes may be useful into dividing products into low and potentially high-risk classes (effectively digestible and persistent nanomaterials). Such restricted labelling, associated with publicly available risk assessment data could help foster public confidence and allow consumer choice in the use of this technology.

Further reading and useful websites

The Royal Society has produced a number of reports and submissions related to nanotechnology and its applications, accessible through their website: http://www.royalsociety.org, including:

  1. Nanoscience and nanotechnologies: opportunities and uncertainties (2004).
    http://royalsociety.org/policy/publications/2004/nanoscience-nanotechnologies/ 
  2. Business and nanotechnologies (March 2007)
    A report on a workshop entitled ‘How business can respond to the technical, social and commercial uncertainties of nanotechnology?’
    http://royalsociety.org/policy/publications/2007/business-nanotechnology/ 
  3. Emerging technologies and social innovation (January 2009)
    A report on the third of a series of joint Royal Society and Science Council of Japan (RS-SCJ) workshops looking at developments in nanotechnology in the UK and Japan. This contains links to the reports on the previous workshops.
    http://royalsociety.org/policy/publications/2009/technology-social-innovation/ 
  4. Mind the Nano Gap (2018) https://royalsociety.org/science-events-and-lectures/2018/summer-science-exhibition/exhibits/mind-the-nanogap

The Social and Economic Challenges of Nanotechnology (2003)
Report written for the ESRC by S Wood, R Jones and A Geldart. Copies can be downloaded from
https://www.researchgate.net/publication/200004356/download

Food Standards Agency (FSA)
The main UK government agency which addresses issues related to applications of nanotechnology in food. Their website http://www.food.gov.uk contains a section dedicated to nanotechnology (search for ‘nanotechnology’)

Department of Environment, Food & Rural Affairs (DEFRA)
DEFRA also oversees the regulation of certain areas of the food chain in the UK, including animal welfare, safety standards, and environmental issues:  https://www.gov.uk/government/organisations/department-for-environment-food-rural-affairs. The website provides a link to the latest DEFRA report ‘Characterising the potential risks posed by engineered nanoparticles (2012)’, which builds on the governments previous 2005 and 2006 progress reports, and provides an update on the Defra's Nanotechnology Research Co-ordination Group’s objectives and associated programme of work: https://www.gov.uk/government/publications/characterising-the-potential-risks-posed-by-engineered-nanoparticles 

The European Food Safety Authority (EFSA)

EFSA provides independent scientific advice and communication on existing and emerging risks, which includes the area of nanotechnology. http://www.efsa.europa.eu/en/aboutefsa.htm
Information on nanotechnology, and links to the work of EFSA and the documents generated in this area can be found at  http://www.efsa.europa.eu/en/topics/topic/nanotechnology.htm 

US Food and Drug Administration (FDA)
Their position with regard to regulation and use of nanotechnology is outlined on their website: http://www.fda.gov/ScienceResearch/SpecialTopics/Nanotechnology/ 

US Environmental Protection Agency - Control of Nanoscale Materials under the Toxic Substances Control Act
Describes the US EPA requirements for the import, manufacture or use of ENMs in commercial products. http://www.epa.gov/opptintr/nano/ 

Down on the Farm - the impact of nanoscale technologies on food and agriculture (2004)
Report produced by the environmental lobby group (ETC): http://www.etcgroup.org/, http://www.etcgroup.org/content/down-farm-impact-nano-scale-technologies-food-and-agriculture 

Nanotechnology in Food and Food Processing Industry Worldwide 2003-2006-2010-2015. Helmut Kaiser Consultancy (2004)
A study on nanofoods. The report can be purchased from: http://www.hkc22.com/nanofood.html [25]

Soft Machines: nanotechnology and life. Richard A.L. Jones (2004) Oxford University Press
Explains why things behave differently at the nanoscale from the way they behave at familiar human scales, and why this means that nanotechnology may be more like biology than conventional engineering

Nanotechnologies in Food. Q Chaudhry, L Castle, R Watkins, P O’Brien & H Craighead
Royal Society of Chemistry, RSC Nanoscience & Nanotechnology Series14 (2010). ISBN-13: 9780854041695

Is Nanotechnology going to change the future of Food Technology? Morris VJ. The International Review of Food Science and Technology 3 (2005) 16-18
This article discusses naturally occurring nanostructures in food and their changes during processing and cooking.

Emerging Roles of Engineered Nanomaterials in the Food Industry, Morris VJ – ‘Trends in Biotechnology’ (2011) 29 [10] 509-516 This article discusses applications on nanotechnology and developments in the definition of nanomaterials

International Union of Food Science and Technology (IUFoST)
‘Nanotechnology and Food’ Information Statement: http://www.iufost.org/

Institute of Nanotechnology (IoN)
The IoN works closely with governments, universities, researchers, and companies worldwide on developing and promoting all aspects of nanotechnology. It also serves as a key organizer of international scientific events, conferences and educational courses designed to encourage nanotechnology uptake by industry, as well as stimulating interest in less developed countries. http://www.nano.org.uk/ 

European Commission and Nanotechnology
Their website provides links to several documents related to progress on the definition of nanomaterials and possible regulation and labelling: http://ec.europa.eu/nanotechnology/index_en.html 

Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)
Provides opinions on emerging or newly-identified health and environmental risks such as those which might be posed by nanotechnology, and on broad, complex or multidisciplinary issues  http://ec.europa.eu/health/scientific_committees/emerging/index_en.htm 

EU (2010) Report on the European Commission's Public Online Consultation ‘Towards a strategic nanotechnology action plan (SNAP)’ 2010-2015http://ec.europa.eu/research/consultations/snap/report_en.pdf 

EU (2011) REGULATION (EU) No 1169/2011 of the European Parliament and of the Council (25th October, 2011) on the provision of food information to consumers

Important because it suggests that in order to inform consumers of the presence of engineered nanomaterials in food, it is appropriate to provide for a definition of engineered nanomaterials:

http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2011:304:0018:0063:EN:PDF 

Wijnhoven, SWP, Peijnenburg WJGM, Herberts CA, Hagens WI, Oomen AG, Heugens EHW, Roszek B, Bisschops J, Gosens I, van de Meent D, Dekkers S, de Jong WH, van Zijverden M, Sips AJAM, Geertsma RE. (2009). Nano-silver - A review of available data and knowledge gaps in human and environmental risk assessment. Nanotoxicology 3,109-138.

Wijnhoven, SWP (2012). Human health risk assessment of nanosilver  - Overview of available data. http://www.bfr.bund.de/cm/349/human-health-risk-assessment-of-nanosilver.pdf[38]

Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR)

Request for scientific opinion on Nanosilver: safety, health and environmental effects and role in antimicrobial resistance http://ec.europa.eu/health/scientific_committees/emerging/docs/scenihr_q_027.pdf 

Faunce T & Watal A (2010). Nanosilver and global public health: international regulatory issues. Nanomedicine 5, 617 – 632.

An JS, Zhang M, Wang S & Tang J. (2008). Physical, chemical and microbiologicalchanges in stored green asparagus spears as affected by coating of silver nanoparticles-PVP. LWT Food Sci. Technol. 41, 1100 – 1107.

Blaser SA, Scheringer M, MacLeod, M & Hungerbühler K. (2008). Estimation of cumulative aquatic exposure and risk due to silver: contributionsof nano-functionalized plastics and textiles. Sci. Total Environ. 390, 396 – 309.

Kim B, Park CS, Murayama M & Hochella MF. (2010). Discovery and chacterisation of silver sulfide nanoparticles in final sewage sludge products. Environ. Sci. technol. 45, 7509 – 7514.

Judy JD, Unrine JM & Bertsch PM. (2011). Evidence for biomagnifications of gold nanoparticles within a terrestial food chain. Environ. Sci. Technol. 45, 776 – 781.

Unrine JM. Tysusko OV, Hunyadi SE, Judy JD & Bertsch PM. (2010). Effects of particle size on chemical speciation and bioavailability of copper to earthworms (Eisenia fetida) exposed to copper nanoparticles. J. Environ. Quality 39, 1942 – 1953.

Werlin R, Priester JH, Mielka RE, Krämer S, Jackson S, Stoimenov K, Stucky GD, Cherr GN, Orias E & Holden PA. (2011). Biomagnification of cadmium selenide quantum dots in a simple experimental microbial food chain. Nature Nanotechnol. 6, 65 – 71.

EU Scientific Committee on Food SCF/CS/ADD/EMU/199 Final, 21st February 2003 ‘Opinion of the scientific committee on food on carrageenan’
Review of the safety data relating to the use of low molecular weight carrageenan which expresses the recommendations of the committee for the specifications for the use of carrageenan in food: http://www.cybercolloids.net/sites/default/files/EU-carrageenan-opinion.pdf 

References

1. Kavitha Pathakoti, Najunath Manubolu, Huey-Min Hwar (2017) ‘Nanostructures: current applications and future uses in food science’ Journal of Food and Drug Analysis, 25: 245-253.

2. Trepti Singh, Shruti Shukla, Pradeep Kumar, Verinder Wahler, Vivek K Bajpai, Irfan A Rather (2017) ‘Application of nanotechnology in food science: perception and overview’. Front. Microbiol., 07 August 2017 https://doi.org/10.3389/fmicb.2017.01501

3. L.F Fraceto, R Grillo, G A deMedeiros, V Scognamiglio, G Rea, C Bartolucci (2016) ‘Nanotechnology in Agriculture: which innovation potential does it have?’. Front. Environ. Sci., 22 March 2016 https://doi.org/10.3389/fenvs.2016.00020

4. Groves K, Parker M L. (2013) ‘Electron microscopy: principles and applications’ in Morris V J & Groves K (eds) Food microstructure - microscopy measurement and modelling pp 386-428. Woodhead Publishing Ltd.

5. http://www.fda.gov/ScienceResearch/SpecialTopics/Nanotechnology/ 

6. http://www.publications.parliament.uk/pa/ld200910/ldselect/ldsctech/22/22i.pdf

7. http://www.food.gov.uk/policy-advice/nano/

8. http://www.fao.org/docrep/012/i1434e/i1434e00.pdf

Institute of Food Science & Technology has authorised the publication of the following updated Information Statement on Nanotechnology dated January 2019, replacing that of December 2013.

This updated Information Statement has been prepared by Kathy Groves FIFST, peer reviewed by professional members of IFST and approved by the IFST Scientific Comittee.

The Institute takes every possible care in compiling, preparing and issuing the information contained in IFST Information Statements, but can accept no liability whatsoever in connection with them. Nothing in them should be construed as absolving anyone from complying with legal requirements. They are provided for general information and guidance and to express expert professional interpretation and opinion, on important food-related issues.