Health assessment of Nanomaterials
- Health Risks from Nanomaterials
- Consideration of Exposure Pathways
- Challenges in the Health Risk Assessment of Nanomaterials
- Assessed Nanomaterials in Consumer Products
- Legislation of the Risk Assessment of Nanomaterials
- Nanomaterials in European Chemicals Law (REACH)
- Legal Regulation of Nanomaterials in Cosmetic Products
- Legal Regulation of Nanomaterials on Food Packaging
- Legal Regulation of Nanomaterials in Food
- Legal Regulation of Nanomaterials in Textiles
- Legal Regulation of Nanomaterials in Biocides
There is no general answer to whether nanomaterials or products that contain them may pose health risks for consumers. The BfR’s health risk assessment focuses on specifically manufactured nanomaterials that are used, for example, in cosmetic products, in food packaging and numerous consumer goods.
Compared to conventional materials, nanomaterials have modified and/or new types of properties and functions that raises interests in many areas of application. Production quantities and the number of variants of nanomaterials continue to increase steadily. This may represent an elevated and possibly new type of health burden on the general population, e.g. in case nanomaterials are released from consumer products.
Definition: According to the updated recommendation of the European Commission (2022/C 229/01), a nanomaterial is present if at least 50% of the number of solid particles it contains meet at least one of the following conditions:
- one or more external dimensions of the particles are in the size range from 1 nm to 100 nm;
- the particles have an elongated shape, with two external dimensions being less than 1 nm and the other external dimension being greater than 100 nm;
- the particles have a plate-like shape, with one external dimension being less than 1 nm and the other external dimensions being greater than 100 nm.
It is irrelevant whether this amount is intentionally or unintentionally present in the material.
In the future, this recommendation will be included in the REACH regulation (Regulation concerning the Registration, Evaluation, Authorization and Restriction of Chemicals) and the sector-specific regulations.
More extensive explanations of the most important terms connected with nanomaterials can be found in the BfR’s Nanomaterials FAQ.
Link to the Nanomaterials FAQ.
Any health risk assessment must in particular take into account products which contain nanomaterials in an unbound form or products from which these can be easily released.
Compared to conventional materials, nanomaterials demonstrate altered, and in some cases even new, properties and/or functions. This gives rise to potential health concerns that should be checked, specifically, as part of a risk assessment:
- Toxicokinetics: Due to their small size, nanomaterials can pass through some barriers in the body more easily and are therefore distributed differently in the body than corresponding non-nanoscale materials.
- Biopersistence: Some nanomaterials could remain in specific organs for a very long period of time, so that significant amounts can accumulate over time and may lead to chronic health issues
- Reactivity: Nanomaterials have a large specific surface area (surface to volume ratio), which is often associated with greater reactivity. This increases the risk of persisting inflammatory responses, which can lead to organ damage.
Principally, all exposure pathways are to be considered in the risk assessment of nanomaterials, not the least due to their use in a number of different consumer products: exposure via the respiratory tract (inhalation), via the digestive tract (oral), and via the skin (dermal).
Absorption Via Respiratory Tract
Scientfic evidence has shown that inhalation of nanomaterials poses the greatest risk for adverse health effects, as inhaled nanomaterials can lead to inflammation processes in the lungs, which in can lead to organ damage and also to the development of tumours, if the inflammation persists. Biopersistent fibres have been demonstrated to be particularly hazardous, by inducing an asbestos-like pathology, causing tumours in the lungs and peritoneum (mesothelioma). An additional systemic health risk may arise when after inhalation of nanomaterials, a small fraction can reach other organs.
Absorption Via Digestive Tract
Risks from absorption of nanomaterials via the gastrointestinal tract have not yet been proven conclusively. However, even after ingestion it was shown that a small proportion of the particles can be transported to other organs.
Absorption Via Skin
According to the current state of knowledge, the amount of nanomaterials absorbed through intact human skin is very low.
In a risk assessment, each nanomaterial has to be examined separately and each application has to be considered individually. The basic principles of a health risk assessment also apply to nanomaterials: both the potential health hazards (harmful effects) and the actual exposure need to be examined. However, the risk assessment of nanomaterials faces some specific challenges:
- Physico-chemical characterisation: Due to the particulate nature, additional parameters are to be considered when conducting a physico-chemical characterisation. Furthermore, it is also necessary to perform characterisation within different biologically relevant media, since some physical-chemical properties may change depending on environment.
- Exposure data: There is often a lack of reliable data on consumer exposure.
- Testing regulations and guidelines: Adaptation of the testing regulations and guidelines of the Organisation for Economic Cooperation and Development (OECD) for nanomaterials health assessments has not yet been completed.
- Assessment concepts and screening procedures: Due to the large number of variants, the development of new assessment concepts (e.g. in terms of grouping) and reliable screening methods are of particular importance.
Risk assessments have been performed for a large number of nanomaterials whose use in cosmetic products has been notified or that have to be approved in accordance with the EU Cosmetics Regulation. The assessments are published on the Scientific Committee on Consumer Safety (SCCS) website (https://ec.europa.eu/health/scientific_committees/consumer_safety/opinions_en#fragment2).
The European Food Safety Authority (EFSA) has assessed a number of nanomaterials used in plastics that potentially gets into contact with food. The assessments are published in the EFSA Journal and the approved nanomaterials are listed in Annex I of the corresponding Regulation (EU) No. 10/2011.
Substance evaluations have been performed within the framework of the overarching EU chemicals regulation REACH, which also included nanoforms with consumer relevance (e.g. zinc oxide).
Health risk assessments of nanomaterials are undertaken within the framework of various European legislations.
The overarching European chemicals regulation REACH and some product-specific regulations have already been adapted to make them applicable for nanomaterials. The current status of the most important sectors is described below.
Not all products are regulated by their own legal regulations. However, in principle all manufacturers are obliged by the European Product Safety Directive to guarantee the safety of their products (Section 3 of the Product Safety Act).
In European chemicals law, the REACH Regulations (Regulation for the Registration, Evaluation, Approval and Restriction of chemical substances (EC) No. 1907/2006) has been amended twice to take into account the special features of nanomaterials. The revised annexes of Regulation (EU) No. 2018/1881, which came into force on January 1, 2020, prescribe how to characterise the “nanoforms” of a substance and specify standard information requirements about nanomaterials which must be submitted, in dossier format, by manufacturers and importers for registration. Nano-specific information requirements include information on substance identity and physical-chemical characterisation (described in Annex VI of the REACH Regulation), as well as human and environmental toxicological endpoints (depending on the tonnage described in Annexes VII, VIII, IX and X of the REACH Regulation). In addition, Annex II of the REACH Regulation was adapted with Regulation (EC) No. 2020/878, which describes the requirements for the preparation of safety data sheets.
The European Chemicals Agency (ECHA) supports the implementation of the legal requirements for nanomaterials through series of technicalguidance, e.g. for the registration and substance identification of nanoforms or for the health assessment of nanoforms. In addition, as part of dossier evaluation, the compliance with the requirements is checked. For selected substances (including nanomaterials or the nanoforms of a substance) for which concerns are identified, a Member State can commit to perform substance evaluation in collaboration with ECHA. In addition to the dossier, substance evaluation also considers other scientific evidence to draw a conclusion whether a possible health risk arising from the use of the nanomaterial has been adequately controlled.
In accordance with the EU Cosmetics Regulation (EC) No. 1223/2009, nanomaterials are explicitly accounted for in cosmetic products. According to Article 16 of the EU Regulation, cosmetic products containing nanomaterials have to be reported to the EU Commission since January 11, 2013. Cosmetics that contain nanomaterials must be reported electronically six months before being launched on the market, in addition to the notification requirement in accordance with Article 13 of the EU Regulation. Comprehensive information about the nanomaterial (specification of the physical and chemical properties, estimation of the quantities being distributed, foreseeable exposure conditions, as well as the toxicological profile and safety data) must be provided. Exceptions are cosmetic products that contain nanomaterials in accordance with the requirements of Annex III, as well as nanomaterials that are approved as dyes, UV filters or preservatives. The European Commission published a report in July 2021 on the use of nanomaterials in cosmetic products: https://eur-lex.europa.eu/legal-content/DE/TXT/PDF/?uri=CELEX:52021DC0403&from=EN.
In the event that the EU Commission raises concerns about the safety of a reported nanomaterial, a scientific committee of experts - the Scientific Committee on Consumer Safety (SCCS) - meets to issue an opinion within six months (Article 16 Paragraph 4). In cases where further data and clarification is required, another 6-month period will be granted for assessment after receipt of the missing information. Certain categories of cosmetic ingredients - e.g. dyes, UV filters and preservatives, including their nanoforms - can only be used in cosmetic products once they have undergone assessment by the SCCS and are approved by the European Commission, i.e. when included in Annexes IV-VI of the EU Cosmetics Regulation (Article 14 Paragraph 1 Letters c to e). The SCCS guidelines for the assessment of nanomaterials in cosmetic products (SCCS / 1611/19), and the latest version of the SCCS Notes of Guidance, form the basis of the risk assessment. The SCCS assessment forms the basis for regulatory decisions (ban of a nanomaterial in cosmetic products or inclusion in one of the positive lists of the EU Cosmetics Regulation).
If cosmetic products contain nanomaterials, this must be indicated in the list of ingredients. The name of these components must be followed by the word "nano" in brackets. The labelling requirement applies to all nanomaterials in cosmetics.
At the same time, the European Commission will continue to review the provisions of the regulation relating to nanomaterials, taking into account scientific progress, and proposing appropriate changes if necessary.
Food packaging is subject to the overarching Regulation (EC) No. 1935/2004. It provides general regulation for materials and objects that are intended to come into contact with food. This regulation does not yet contain any nano-specific adaptations nor does it define the term nanomaterial. However, it stipulates very generally that, in principle, all materials and objects shall be manufactured in such a way that, under normal or foreseeable conditions of use, they do not release any constituents into food in quantities that are likely to hazardous to human health, cause an unacceptable change in the composition of the food or impair the organoleptic properties (i.e. taste, smell, colour) of the food.
In addition, Regulation (EU) No. 10/2011 governs plastics in food contact more precisely. However, this does not define the term nanomaterials either, Rather, it generally stipulates (in Article 9) that substances in nanoform may only be used if they have been explicitly assessed and included in Annex I accordingly.
Scientific assessment falls within the remit of the European Food Safety Authority (EFSA). The EFSA guidelines for the assessment of nanomaterials in the food and animal feed chain, which also covers food contact materials, form the basis for risk assessment (EFSA Journal Vol 16, Issue 7, 2018). EFSA has already assessed some nanomaterials for uses in plastics and the European Commission has approved them on the basis of a positive assessment. The reason for the decision was that the relevant nanomaterials cannot migrate from the plastic into the food. The approved nanomaterials (e.g. zinc oxide, silicon dioxide, titanium nitride, soot, nanoclay) are listed in Appendix I of Regulation (EU) No. 10/2011.
The BfR issues recommendations for areas that are not yet regulated by legal provisions, such as silicones, natural and synthetic rubber or paper, card and cardboard for contact with food. Unless otherwise stated, the entries in the BfR recommendations on food contact materials are based on the risk assessment of substances with non-nanosized particle and do not apply to artificially engineered nanomaterials.
Food is subject to Regulation (EU) 2015/2283 on novel foods (Novel Food Regulation). All foods that consist of or contain engineered nanomaterials are considered novel and require assessment and approval. This falls within the remit of the European Food Safety Authority (EFSA). The EFSA guidelines for the assessment of nanomaterials in the food and animal feed chain form the basis for risk assessment (EFSA Journal Vol 16, Issue 7, 2018). So far, no specifically engineered nanomaterial has been approved for use in food in the EU.
The use of food additives is regulated in various legislations. EU Regulation (EC) No. 1333/2008, Regulation (EU) No. 1129/2011 and other amending regulations forming the basis. During approval, food additives are assessed with regard to their effects on health as the form in which they are to be launched on the market. This also falls within the remit of the European Food Safety Authority (EFSA). However, different approved food additives have a very broad particle size distributions, and particles smaller than 100 nm (nanometres) have already been detected in these additives. The proportion of nanoparticles varies and can be 10 to 30% by total particle numbers. However, since the particles with one or more external dimensions in the range from 1 to 100 nm make up less than 50% of the number size distribution, they do not fall under the definition of nanomaterials. If, on the other hand, additives such as these are manufactured and marketed as a nanomaterial, a health risk assessment and approval would be required.
As a result of the adoption of the Food Information Regulation (EU) No. 1169/2011, labelling of all ingredients available in the form of technically engineered nanomaterials has been mandatory since 2014. These must be included clearly in the list of ingredients, followed by the word "nano" in brackets.
As consumer goods, textiles such as clothing or bedding that make contact with the human body, both temporarily or otherwise, are subject to the provisions of the legal code governing food, consumer goods and animal feed. Nanomaterials in textiles are not subject to any specific legal regulations. However, since 2013, the application of biocides in textiles has been regulated by the Biocide Regulation (EU) No. 528/2012.
Currently, no regulations cover the use of titanium dioxide in textiles as UV protection or carbon nanotubes to make the textile fibres more durable. However, according to the German Food and Feed Code, as well as the German Product Safety Act, manufacturers and distributors are responsible for ensuring that even textiles featuring nanomaterials do not pose a health risk for consumers.
Biocides are subject to the EU Biocide Regulation (EU) No. 528/2012, which contains a definition of nanomaterials. In general, the Biocide Regulation requires a two-stage process. In the first step, a decision is made on the approval of the biocidal active substance within a European assessment procedure. The approved biocidal active substance are recorded in a positive list. Approval of an active substance does not include its nanoform(s). An active substance in nanoform must be assessed and approved separately and must also be specified explicitly as a nanoform. In the second step, the individual biocidal products containing this active substance must either be authorised by the member states or by the European Chemicals Agency (ECHA). The ECHA also maintains a corresponding register of all authorised products. If the biocidal products contain non-active substances in nanoform, the assessment of these fall within the scope of the REACH Regulation.
So far, only a few nanosized biocidal active substances have been assessed. One approved nanosized biocidal active substance is synthetic amorphous silicon dioxide (SiO2) in product type 18 (insecticides, acaricides and products to control other arthropods).
In accordance with the EU Biocide Regulation, the names of all nanomaterials contained in the biocidal products must be indicated on the label, followed by the word "nano" in brackets.