NanoSafePack - Safe Handling and Use of Nanoparticles in Packaging

The main goal of the project is to develop a best practices guide to allow the safe handling and use of nanofillers, considering integrated strategies and best practices to control the exposure in industrial settings, and provide stakeholders with scientific data to minimize and control the release and migration of submicron sized particles from the polymer nanocomposites placed on the market.

To achieve this aim, a complete hazard and exposure assessment has been conducted to obtain new scientific data about the safety of polymer nanocomposites. The work focuses on a selected set of relevant fillers and polymeric matrices to the packaging sector, including including layered nanoclays, silver (Ag), silicon dioxide (SiO2), zinc oxide (ZnO), and calcium carbonate (CaCO3) nanoparticles. The polymer matrices selected on the basis of market data and applicability in the packaging industry included polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), as well as poly‐lactic acid (PLA), a promising biodegradable polymer.

The results of the project are compiled and described in a best practices guide, main target of the project, providing a better understanding of the safety  issues related to the use of nanofillers across the packaging life cycle. The guide is primarily intended for utilisation by small and medium‐sized enterprises (SMEs) and larger companies involved in the manufacture of polymer‐based nanocomposites for packaging applications, but it´s also of value to trade associations related to the packaging industry, regulatory bodies and relevant international organisations such as the European Food Safety Authority (EFSA), the European Agency for Safety and Health at Work (EU‐OSHA), as well as international standardisation bodies such as the European Committee for Standardization (CEN).

 

 Background

The use of nanoparticles in packaging manufacturing is an area with a broad applicability, providing the opportunity to develop new and innovative packaging materials, principally derived from the manufacture of nanocomposites, polymers reinforced with materials and/or particles that have one or more dimensions of the order of 100 nm or less, commonly called nanofillers or nano-reinforcements.

The development of the polymer nanocomposite industry is rapidly emerging and has recently gained momentum in mainstream commercial packaging, particularly in food packaging where the use of nanocomposites is already a reality. The use of nanofillers - which are typically inorganic and organic materials such as metals (Al, Fe, Au, or Ag), metal oxides (ZnO, Al2O3, TiO2), mixed metal oxides, clays, and carbon nanotubes (CNT) -  improves the volume properties, surface properties, dimensional stability, chemical stability and other functional properties of the reinforced polymers, conferring photocatalytic, optical, electrical and thermal stability. 

Nanofillers can be introduced into polymers at rates ranging from 1 - 10 % (in mass) depending of the type of polymer matrix, which includes thermoset polymer matrices such as polyesters (UP), polyamide, or polyurethane (PUR), and thermoplastics such as polyethylene (PE), polypropylene (PP) and polystyrene (PS).

Nanofiller-reinforced polymers compare favourably with conventional polymers in terms of gas barrier properties, flexibility, temperature/moisture stability etc.  Moreover, nanoparticles may serve as means of interaction between food and the environment and can therefore play a dynamic role in food preservation and protection (active and intelligent packaging)

These new properties, and the further development expected in the near future, results in a continuous growth of nanocomposites in the market.  Composite materials are rapidly becoming a mainstream technology and material of choice within many industries, expected to reach 19 % of nanotechnology products and applications in global consumer products by 2015. Moreover, the global use of nanocomposite materials is forecasted to grow from nearly 225,000 metric tons in 2014 to almost 585,000 metric tons in 2019, with a market of greater than €3 billion projected by 2019.

Alongside the benefits of nanofillers in packaging applications, there is an on-going debate about the potential effects of nanomaterials on human health and the environment. The uncertainties are exacerbated by the range of properties and their interaction with biological processes, which are often very different from those demonstrated by the larger-scale form of the same substance.  It is these differences in the physico-chemical and biological behaviour which results in differences in the potential hazardous properties.

Regarding the risks from occupational exposure to these materials, workers may be exposed to nanomaterials via three main routes: inhalation, ingestion or through skin penetration.  The most common potential risk arises from airborne nanoparticles being released into the workplace, inhaled by workers and potentially depositing in the respiratory tract and lungs.  Nanomaterials may also be unintentionally ingested via hand-to-mouth transfer or contaminated food or water, where they may potentially cross the gut wall, enter the bloodstream and subsequently reach other parts of the bod

Lastly, the risks from skin penetration are believed to be lower than that of inhalation; the skin does not allow nanomaterials to easily penetrate, although damaged skin may be less protective.  Nevertheless, it is highly recommended that simple yet effective measures are taken to prevent or limit releases which may lead to potential inhalation, ingestion and skin contact through implementing risk management procedures. 

In addition to worker exposure, releases can also lead to environmental exposure.  The scale and nature of industrial processes can inevitably result in fugitive emissions, which may be monitored and regulated, and inconsequential releases of substances used during the manufacturing of packaging materials which find their way into the environment.

Additionally, once placed on the market, the polymers are susceptible to physicochemical factors such as photodegradation or abrasion, such that, NPs imbedded in the polymer may potentially be released into the environment. Such a release might have an effect to the consumers and the environment and present a barrier on their potential uses.

These aspects have a special relevance for the food packaging industry, where it has raised a number of safety, environmental, and regulatory issues. Therefore, the safety issues related to workers and consumers have to be faced prior to the investment in new resources from the SMEs.

In view of the current situation, the project stemmed from the need to ensure the safety of workers dealing with nanofillers and to guarantee the safety of the nanocomposites placed on the market, avoiding endangering consumers’ health and the environment. 

Concept and Objectives

The solution and main goal proposed by the NanoSafePack project is the development of a best practices guide to allow the safe handling and use of nanoparticles in packaging industries. This guide is primarily intended for utilisation by small and medium-sized enterprises (SMEs) and larger companies involved in the manufacture of polymer-based nanocomposites for packaging applications, but will also be of value to trade associations related to the packaging industry, regulatory bodies and relevant international organisations such as the European Food Safety Authority (EFSA), the European Agency for Safety and Health at Work (EU-OSHA) and the Organisation for Economic Co-operation and Development (OECD), as well as international standardisation bodies such as the European Committee for Standardization (CEN).

The mail goal of the guide is to provide a better understanding of the environmental, health and safety (EHS) issues related to the use of nanofillers across the packaging life cycle, from production to end-of-life, considering proven best practices and measures to ensure the safety of workers and to reduce potential environmental and human health risks at the consumer stage.

Besides the best practices guide, the following scientific, technical and integrated objectives were foreseen:

  1. To identify the specific nanoclays and metal and metal oxide nanoparticles most employed as nanofiller in the packaging industry.
  2. To characterize the endpoints listed by the OCDE in relation to the physical-chemical properties and material characterization of the specific nanofillers: this objective is related to the complete characterization of the most important parameters that may influence the toxicological and airborne behaviour of the target nanofillers.
  3. The characterization techniques and methodologies employed within the project are based on the current recommendations and guidelines of the OECD, and specifically in the list of relevant endpoints included on the guidance manual for the testing of manufactured nanomaterials, which was published by the OECD sponsorship programme for the testing of manufactured nanomaterials in 2010.
  4. To characterize the toxicological profile of the target nanofillers: this objective is related to the definition of the adverse effects of the target nanofillers to relevant cell lines that represent significant exposure and target organs in the human body, including lung epithelium, gastrointestinal epithelium, skin keratinocytes and hepatocytes.
  5. To characterize the ecotoxicological profile of the target nanofillers: this objective is related to the characterization of the uptake potential and toxicity of the target nanofillers in representative aquatic and terrestrial species, including invertebrates and plants. Moreover, a better understanding of the fate and behaviour of the nanofillers in the environment shall be included to contribute to the implementation of regulatory exposure assessment frameworks.
  6. To assess the changes induced by the functionalization of the nanofillers in relation to their toxicological and ecotoxicological profile: this objective is related to the definition of the effects of the use of modifiers in the toxicological and ecotoxicological profile of the target Nanofillers.
  7.  Hazard characterization of nanoreinforcements including functionalizer agents: this objective considers the characterization of the toxicological and ecotoxicological properties of the modified    nanofillers.
  8. To characterize the toxicity and ecotoxicity of the nanocomposites us such: this objective refers to the definition of the potential adverse effects of the nanocomposites to the human health and the environment, including the generation of new information on the no observed effect levels (NOEL) and sub-lethal concentrations for relevant cell lines and organism from representative environmental compartments.
  9. To characterize the exposure to nanoparticles through the development of specific exposure scenarios: this objective refers to the definition of the levels of exposure in the production sites, including the complete definition of the number of particles, average particle diameter and size distribution at different time periods and different stages of the nanocomposites life cycle.
  10. To evaluate the effectiveness of common risk management measures against target nanomaterials: this objective includes the experimental characterization of the performance of respiratory and dermal protection equipment, protective clothes, eye protection and engineering controls.
  11. To identify the impacts of the target nanomaterials and nanocomposites in the environment considering a life cycle perspective. 
  12. To develop best practices and recommendations to support the safe handling and use of nanomaterials in packaging industries.
  13. To validate the applicability of the best practices guide developed by SMES, including the evaluation of the viability of the solutions proposed in the industrials settings, the characterization of the effectiveness of the risk management measures proposed, and the evaluation of the improvement of the nanocomposite’s safety once applied the best practices referenced on the guide. 

The concept of NanosafePACK stems from the need to ensure the safety of workers dealing with nanoparticles and to guarantee the safety of the nanocomposites placed on the market, complying with the European regulation and avoiding endangering consumers’ health and the environment.

Moreover, significant regulatory concerns from the European Commission have arisen about unforeseen risks likely to arise from nanocomposites, so that, the project worked to provide legislators and industry with new knowledge for appropriate risk management and decision making, creating the basis to meet the current regulation related to the use of nanometer range additives.

Advances over the state of the art

Due to the variability of the properties of the nanoreinforcements considered and the evident lack of information about the potential effects and impacts of nano-sized materials on human health and environment, we have not been able to identify any manual or guide that can provide valuable advice about the use of layered organoclays and metal oxide particles. This is what the NanoSafePACK project will provide, a specific guide to improve the use of nanoparticles in order to develop functional materials, controlling the exposure to nanoparticles in the worker environment and minimizing the release potential during the service life of the polymer.

Besides the above, the NanosafePACK project will work to progress beyond the current knowledge related to applicability of nanoparticles as nanofillers, as well as the enhancement of knowledge about the health and environmental impacts of the target nanoparticles and nanocomposites. In this sense, the project will take into account the “baseline data” in order to measure our progress, considering also the current research activities related to the field of work of NanosafePACK, avoiding the duplicity of efforts.

The main baseline data to be considered will be:

  • Studies and research concerning the applicability of nanoparticles as nanofillers.
  • Available data on toxicological and ecotoxicological properties of the target NPs and nanocomposites
  • Available data on migration studies
  • Available data on exposure assessment methodologies
  • Current risk management strategies recommended
  • Existing manuals and handbooks

In relation to the existing references, several studies on polymer nanocomposites have been identified in the bibliography, however, none of them represent a direct guide to be applied at all stages of nanocomposites production, use and disposal, and do not take into account the concerns  related to workers and consumers safety. In addition, we have not been able to identify any study specifically relating to the potential release of nanoparticles from the polymeric matrix, and even fewer in relation to the methodologies to be employed in migration studies involving nanoparticles.

In relation to the emerging research, we have identified several projects working on aspects related with some of the objectives pursued by our project, e.g. safe handling of nanoparticles, risks associated with the production of polymer nanocomposites and toxicological impact of nanomaterials derived from processing, weathering and recycling of polymer nanocomposites, nevertheless, these projects are not specifically aimed at SME trade moulders who will not probably be able to readily get hold of this information. Moreover, these projects are very academic orientated thus, they don’t fully meets the SMEs needs.

In addition, methodologies to assess the exposure and hazard aren’t standardized, so that the results of projects like Nanosafe are difficult to interpret and apply to other conditions. Thus, we aim to develop a best practices guide directly applicable in the nanocomposite industry.

The current handbooks, guides and reports of research projects are not focused on specific nanoparticles used in the current industrial setting of the packaging industry, which can differ enormously from another industrial process involving the use of polymers and nanoparticles. At this stage, our solution is innovative due to the direct application of our members in particular SMEs and industrial settings, as well as providing valuable information to characterize the toxicological profile and potential risk of the new manufactured nanocomposites and also those placed on the market in the recent years.

In relation to nanocomposite safety, the commercial manufacture of nanoparticles is relatively new, so that, there isn’t consensus in relation to the potential migration and release of the nanofillers employed on the nanocomposite industry. In this sense, taking into account physicochemical properties of the nanofillers employed, the possibility of migration is likely. Therefore, manufactures of nanocomposites, with special attention to those who manufacture food contact materials, must predict the potential migration in order to protect the consumer’s health and comply with the current regulation. At this stage, our proposal will study the aspects concerning the migration and release of nanoparticles in the polymeric matrix, providing the SMEs with scientific and valid data to select the less hazardous nanofillers or predict the potential release to the end user.

After studying the existing solutions and emerging research, the consortium has concluded that the submitted project has a high innovative character and will enhance significantly the state-of-the-art in the nanocomposite area. There is a demand that the current solutions are not able to meet, and the other research approaches are not focused in the specific field of the nanocomposite industry. Therefore we have an opportunity to exploit our innovative approach, including the achievement of the results in a reasonable period of time.

On the other hand, due to the current lack of data in the nanotechnology area, mainly in relation to the adequacy of testing models and exposure measurements, we have conducted a complete contingency plan, including a detailed risk analysis and the contingency actions to guaranty the progress beyond the state of the art, ensuring that the project results will be addressed.

Impact

The development of the NanoSafePACK project will have a remarkable impact on the European SME Community and their citizens, clearly identifiable due to the hundreds of applications of the nanocomposite materials every day and the hundreds of people who use them. It’s expected a direct impact in the packaging and polymer nanocomposite industry, helping the SME to develop new innovative materials, which provide the end users with new products tailored to their needs. On the other hand, the implementation of the project results will enable the SME Associations, their members and other SMEs across Europe minimise the health impact and environmental risk from the nanoparticles, providing the information to safely design, manufacture and market nanotechnology enable products.

At the moment, much of the research and development work is concentrated on the development of innovative products, considering new properties that improve the final application, while ,at the same time, the safety of the product has been compromised at all stages of nano-products manufacturing, use and disposal. Overall market value will benefit from important consumer preferences toward safe and environmentally friendly products, which will support consumption of high-performance nanocomposites.

 

NanoSafePACK is a Collaborative Project funded under the call Research For SME Association, SME-2011-2 Theme of the European Commission's 7th Framework Programme managed by REA-Research Executive Agency http://ec.europa.eu/research/rea ([FP7/2007-2013] [FP7/2007-2011]) under grant agreement n° 286362