SCIENTIFIC OPINION ON GUIDANCE ON THE RISK ASSESSMENT OF THE APPLICATION OF NANOSCIENCE AND NANOTECHNOLOGIES IN THE FOOD AND FEED CHAIN
INTRODUCTION
Food and feed can contain of elements that have internal structures that can be measured on the nanoscale for example micelles, liposomes or micelles that occur naturally. Nanomaterials is used to categorize materials according to their size.
Application of nanotechnology in agriculture can contribute to improved better pest management and protection of crops through better distribution of the agrochemicals and pesticides, growth agents or hormones. It is also applied in genetic engineering, sensors that are used in monitoring the soil conditions, identity preservation and veterinary medicine.
Application of nanotechnology in food production is used in food additives that improve the stability of foods in the processing and storage. Also used to improve the characteristics of the products, increase the availability of the nutrients in the foods. Same applications are used in animal feeds.
Natural food structures have natural biopolymers such as the carbohydrates, lipids r proteins that have one dimension in the nanometer range which is as result of the process or cooking. This biopolymers can be used to create new food structures.
Engineered particulates nanomaterials that have elements that are completely metabolized in the body or excreted like the Nano emulsions of the nutrients such as vitamins.
Slowly soluble engineered particulate such as the synthetic amorphoussilicon, Nanosilicon or titanium dioxide which is used as a food additive.
In packaging Nano-polymers composite provide lightweight properties and stronger materials that can keep foods secure during transportation, freshness in long storage and safety off from microbial pathogens
EFSA (EUROPEAN FOOD SAFETY AUTHORITY)
As mentioned above the different application of nanomaterials on agriculture, foods and animal feed has its advantages but also its cons. The disadvantages of the nanomaterials have been found to pose various risks.
Engineered nanomaterial (ENM) refer to materials that are produced either intentionally or unintentionally in the production of foods and feeds. A guidance is formulated which tackles the risk. An assessment formed comprises of three main categories of products or classification as indicated in the EFSA, 2011 review. Those that are meant for consumption by animals or humans, agrochemicals applied in plant production and other nanomaterial used that come into contact with foods or feeds such as the packaging material. The guidance on the ENM will comprise applications of nanotechnologies and nanoscience in the entire food and feed chain that are under the terms of reference of EFSA. This will include enzymes, foodadditives, flavorings, food contact materials, feed additives and insecticides.
ENM guidance is based upon several reviews and test that have been conducted under the EPSA. ENM risk assessment has different levels which include identification of hazards and characterization of the hazards. ENM guidance covers testing procedures, requirements additional considerations that will be indicated in the guidance.
ENMA RISK ASSESMENT
Risk of an ENM is caused by the chemical composition, physio-chemical properties, the interactions within the tissues and the potential exposure levels. When applying ENM guidance the physio-chemical characterization is need to identify the ENM. If the guidance is applicable then the results from the testing will provide the necessary information to assess the hazard risk. This hazard assessment combined with the exposure assessment are the basis of risk characterizations.
The chemical and physio-chemical properties such as shape, size, surface reactivity and solubility will influence the absorption, distribution, metabolism and excretion (ADME). In any test of the ENM there are some general rules that ae applied. indicators of potential toxicity that are considered when choosing an appropriate testing strategy include: high levels of reactivity such as the catalytic ,biological or chemical ,complex morphology ,interactions with the biomolecules such as the enzymes ,complex transformations and ENM used as anti-microbial.Indicator of a potential for high risk exposure include;high production volumes in the applied field,high mobility of the Nano-forms in the organisms for example transport through the cell membranes or bio-accumulations.
ENM adverse effects can be reduced by certain factors, which are based on the specific exposure scenario being considered and also loss of Nano-properties. Loss of Nano-properties allows reliance on conventional risk assessment and the Nano-specific risk procedures will not be required. Properties that indicate loss of Nano-properties include: rate of dissolutions increases for example in food/feed matrix or in water, rate of degradability increases ,presence of strongly bound aggregates which are determined by the process of production and fixed permanent bonding in matrices.
HAZARD IDENTIFICATION AND CHARACTERISATION
When identifying the hazards and characterization different approaches will be made. The procedure will involve:
General consideration – according to EFPSA ,2009 report showed that data available on oral exposure to ENM ,their absorption,distribution,metabolism and excretion (ADME) and any related toxify is very limited. Data available is mostly in vitro studies or from the vivo studies using exposure routes other than oral means. For hazard characterization ,the relation of the toxicity to various dose metrics that can be used are still under discussion as several dose metrics are being considered in addition to mass for example number concentration or even surface area.
Toxicity testing outline-toxity testing strategy will be determined by the occurrence of
ENM in the Toxicity testing
In Toxity testing strategy six cases are used which include: (1)No persistence of ENM in preparations/formulations as marketed-under this enough evidence is gathered which is used to show that ENM use does not result in presence of ENM or its degradation or solubilisation products in the food or feed ,therefore there is no need for any additional testing.(2) No migration from food contact materials (i.e. no exposure)- this is informed that no migration and there is no exposure to ENM via the food (3) Complete ENM transformation in the food/feed matrix before ingestion–EFSA guidance should be applied when the transformation of the ENM into a no-Nano form in the feed or food matrix is found to be complete before ingestion (4)Transformation during digestion–evidence is gathered here to prove that an ENM dissolves or degrades completely in the gastro-intestinal tract with no absorption of the ENM. (5) Information on non-Nano form available- when information on nonfarm is availed and some of the ENM remain in the food or feed matrix and also in the gastro-intestinalfluids, testing procedure recommended will involve comparing information on the ADME against the toxity of the non-Nano form (6) No information on non-Nano form available-in this case the approach for toxicity tests for ENM will follow the EFSA guide to suit the intended use.
Exposure assessment, principles applied are similar to the methods discussed in Kroes, et al, 2002: EFSA, 2006, 2009d. Which shows there’s no difference in food or feed sampling and variability in composite samples and the variations in the concentrations between the samples from assessment of exposure of micro or macroscale or the dissolved chemicals.
Risk characterization is the step in which the all the details from the hazard identification and hazard characterization is combined with information from the exposure assessments and any other relevant information from other ENM or non-Nano forms
Uncertainty analysis is discussed in the EFSA, 2009 .in the report general principles that are to be applied in the identification of the data sources, criteria to be used for inclusion and exclusion of data, dataconfidentiality, all assumptions and uncertainties are highlighted. This then informs on the recommendations on how to deal with uncertainties under risk assessments which help in addressing uncertainties in the ENM risk assessment risk. More guidelines are borrowed from the EPSA, 2006 report which offers more practical solutions on how to approach the ENM risk assessment. Uncertainties will be catered for in various categories such as in hazard characterization of the ENM, in the physio-chemical characterization of the ENM, in exposure assessment and also in the risk characterization.
CONCLUSION
Rapid growth of nanotechnology has resulted in growth of the innovations and opened up more opportunities in industrialization. More so its application in agriculture and food and feed chains which will involve from the planting ,growth, harvest and all post-harvest treatments for the foods. The technology is good in particular in agriculture as we can now increase our yields and still preserve excess harvest. Foods can be stored for longer and in fresh states all thanks to the application of Nano science. However good this is to the industries it has its shortcomings as the same technology might end up being detrimental to the same human beings its meant to benefit. This has necessitated the drafting of the EPSA guidelines which are used to regulated and assess the possible risks that come with use of Nano-technology on foods for human and animal consumptions. This guidelines keep all aspects of the agriculture sector that is from the inputs used in plants to the very end in the packaging of the same foods and also places where this foods are stored. This aimed at ensuring that food and feeds available are not only of good quality but also food safety is observed.
Agricultural aspect of using nanotechnology is very sensitive and not many countries have rules stipulated that can be used in regulating its use. In the EU it provides guidelines and regulations that offer a binding framework for manufacturers, importers and also users. Several legal acts are incorporated under this and will include: legal acts for the pesticides risk assessment ,this focuses on the chemical compounds used to kill or repel or control weeds and crop protection before and after harvest, legal acts for foods and feed risk assessment which aims at ensuring high levels of protection of both the animals and human health in relation to food and legal act of food contact material and risk assessment, this covers all the materials that will come into contact with the foods. This partly forms the basis for the EPSA guidelines as the guidelines will be formulated around this three aspects or categories
References List
Amenta, V., Aschberger, K., Arena, M., Bouwmeester, H., Moniz, F.B., Brandhoff, P., Gottardo, S., Marvin, H.J., Mech, A., Pesudo, L.Q. and Rauscher, H., 2015. Regulatory aspects of nanotechnology in the agri/feed/food sector in EU and non-EU countries. Regulatory Toxicology and Pharmacology, 73(1), pp.463-476.
EFSA Scientific Committee, 2011. Guidance on the risk assessment of the application of nanoscience and nanotechnologies in the food and feed chain.EFSA Journal, 9(5), p.2140.
Kroes, R., Müller, D., Lambe, J., Löwik, M.R.H., Van Klaveren, J., Kleiner, J., Massey, R., Mayer, S., Urieta, I., Verger, P. and Visconti, A., 2002. Assessment of intake from the diet. Food and Chemical Toxicology, 40(2), pp.327-385.
