Background

Concept

The project concept is based on the sustainability principle, which means that the use of new materials, like engineered nanomaterials and associated products, must not only meet human needs of the present but also of future generations. This also means that all possible effects occurring along a products life-cycle containing these new materials must be fully taken into account as well as their final destiny. Also included in the concept is the use of scarce resources by securing recyclability and avoiding dissipative losses. This concept will be tested and realized by characterizing the properties of selected relevant nanomaterials and products at the various stages of their lifecycle in relation to possible impacts on human health and the environment and by taking reuseability, recyclability and/or ability for final treatment and/or disposal and reintegration into geological cycles as an option for the development of sustainable products into account.

Reason

The behaviour and properties of materials at the nanoscale can be quite different from that at larger scales. Nanomaterials have a much larger surface to volume ratio than larger particles of the same material, which can affect their chemical and physical properties. Quantum effects dominate the behaviour of materials at the nanoscale. Consequently, there is a considerable amount of international research and development activity being undertaken into the exploitation and commercial application of nanomaterials for a wide range of applications.

At the same time, there is an increasing concern that the beneficial properties of nanoscale particles might also have negative impact on human health and the environment. For example, it is expected that the increased surface to volume ratio will make particular chemicals more toxic because these particles will be more absorbable and capable to cross cell membrane or the blood-brain barrier. The obvious lack of our present knowledge on the real hazard and impact of nanomaterials and associated products is due to the fact that there is practically only little data available on (both long and short term) toxicology of and exposure to nanoparticles. We still lack an understanding on how results from existing studies can be extrapolated and transferred to manufactured nanomaterials.

Since production of nanotechnology-based industrial and consumer products is dramatically increasing, also the amount of products reaching the end of their life-cycle is increasing. But due to the rather short time perspective, we still do not know how and to what extent toxic nanomaterials may be released or may leach from products to the environment, or how they are transported, transformed or may accumulate in humans and ecosystems, e. g. when directly used, or indirectly after final treatment and/or disposal in land fills (Meyer et a., 2009). For this reason, there is a strong need to improve our present knowledge on the fate and impact arising from the use of products containing these new materials along the whole product chain, and to explore and develop new innovative solutions for their sustainable use, re-use, recycling and final treatment or disposal. The proposed NanoSustain project will address all these topics that have been specified in the Work Programme of the present Call.

Impact of nanomaterials

Although nanotechnology will help to reduce environmental and human health hazards, for example through better solar cells, replacement of hazardous chemicals, improved pollutant  extraction or prevention technologies, unfavourable safety aspects and concerns need also be addressed. However, this is a complex task, as differently shaped nanoparticles of the same substance may have very different properties.

Looking beyond the potential technical risks associated with nanomaterials, there is actually only scarce information available about the impact of nanomaterials on non-human species, on ecosystems or the global environment (Oberdörster et al. 2005). Even within established questions of toxicology we still do not know how different nanoparticles exactly (inter)act in the human body or the environment, which means that more data is needed. There is a particular need to address the potential impact of nanomaterials along the lifecycle of a product, from manufacture through disposal (“cradle to grave”). And this ‘life cycle view’ is not only necessary regarding possible (eco)toxicological effects in the different stages of the life cycle of the product, but also regarding the (dissipative) use or consumption of energy and materials (which is in the focus of life cycle assessment (LCA)).

Another problem arises from the fact that the existing relevant regulatory framework (chemicals, wastes, safety) may be adequate for some specific areas, where only small amounts of nanomaterials are used (like in research laboratories), but may not be adequate for the industrial mass production and use of these materials. European legislation1 obliges employers to take measures necessary to ensure the safety and health protection of workers, which should also apply in the case of handling nanomaterials. There are specific Directives relating to the risks to workers due to exposure to carcinogens and mutagens2, chemical agents3, the use of workplace equipment4 and the use of personal protective equipment5. Under the new REACH6 chemical regulations, manufacturers have a duty to ensure that substances placed on the market do not adversely affect human health and the environment. While there is no explicit mention of nanomaterials, they would in principle be covered by these regulations. The Integrated Pollution Prevention and Control Directive7 requires industrial installations to limit emissions and would be applicable also to nanomaterials. The Waste Directive8 requires Member States to take measures to ensure that waste treatment does not have an adverse impact on health and the environment. Consequently, there is a need to evaluate the extent to which existing regulatory and associated risk assessment frameworks (strategies, methodologies and tools), can be applied, or extended to cover mass production, application, and final disposal of nanomaterials and associated products.

Looking at REACH there must be a solution regarding the fact, that some important regulations in REACH are triggered by mass (in tons). This is inadequate for nanomaterials, because for some engineered nanoparticles their number and/or shape could be of higher relevance. Additionally there is a demand for adaptation of the OECD-Guidelines (for hazardous (chemical) substances) to the testing of nanomaterials (definitiosn, standards) (see f. i. German NanoCommission 2008). But we cannot wait until all these data will be collected. We need processes for ‘preliminary assessment’ that deliver ‘preliminary information as the base of precautionary measures. The latter may be based on information about chemical and or physical properties, on quantitative structure activity relations (QSAR), on the probability of exposure (e.g. because of extreme mobility and or persistence), and measures based on it may reach from precautionary measures, aiming at exposure avoidance or reduction, up to principles for a safer (or sustainable) design of nanomaterials and products. Along with the growing (eco)toxicological knowledge about impacts, this ‘preliminary knowledge’ will become less important.

When working with nanomaterials, there are four main aspects of their life-cycle that must be considered: material selection, manufacturing, application, and disposal/recycle. Although most work focuses on the possible toxic effects of nanocomponents after exposure for risk assessment, it is worth examining the potential contribution of these materials to all impacts listed above when they are added to products or processes, to better understand the importance of the underlying choices that are involved with the implementation of a nanotechnology. Therefore, understanding the toxicity of nanomaterials and nano-enabled products is important for human and environmental health and safety as well as public acceptance.

In numerous toxicological studies it was shown that nanoparticles have implications on the human health inducing, e. g., pulmonary and systemic inflammation. It was also shown that nanoparticles inhaled can translocate to different parts within the human body, including the brain. (Oberdörster et al. 2005, Kreyling et al. 2006). Data available on the (eco)toxicity of nanomaterials is still limited, but studies prove that there are toxic effects on wildlife and a potential for bioaccumulation in various organisms (Handy et al., 2008).

Fate of nanomaterials

Our current knowledge and the available scientific data on nanoparticles characterisation, detection and measurement, their transport, toxicology, exposure and persistence is still insufficient, to allow an accurate and reliable assessment of their final fate in the environment.

But the increasing amount of nanomaterials produced world-wide raises issues on their destiny when released into the environment and on possible hazards due to accumulation in animals, plants and the human body. Metallic nanoparticles may be extremely resistant to degradation and may accumulate in waters or soils. They may aggregate, which in turn will change their properties compared to single nanoparticles, be transported and accumulate in soils, groundwater and sediments. Existing regulations are based on parameters that may not be appropriate for nanoparticles in solution or in suspension.

Concentration data alone is inadequate to quantify the true exposure to nanomaterials, but needs accurate measurement of other nano-specific parameters, like surface area and reactivity. More appropriate analytical methods are required to reliably detect nanoparticles in various compartments and measure their physico-chemical properties in air, water, soil, and consumer products, the media in which humans and ecosystems are exposed to. Better analytical techniques are required to detect these particles in cells, fluids, or plant tissues. Existing methods to assess environmental exposure levels are not appropriate to determine their environmental fate and current risk assessment procedures need to be modified for adequate hazard characterization (Mueller and Nowack 2008).

There is a distinct need of data on the properties, toxicokinetics and degradability of nanoparticles to better understand where, in which form and to what extent nanoparticles will end up in the environment, to develop more accurate impact assessment models and to find efficient solutions for product design that favours their reuse and recyclability.

The proposed NanoSustain project will address this need for more reliable data on the fate of nanoparticles by developing technical solutions and advanced computer-based models to support the assessment of the hazard, distribution and fate of nanomaterials that may be released from products.

Regulation should be based on scientific evidence of harmful effects of specific nanopar­ticles and how mobile these particles are in the environment. Although it has been shown that some nanoparticles have toxic effects in the laboratory, little is known about their mobility and uptake in organisms under real world conditions. Further research is needed on interactions between nanoparticles and environmental matrices (water, sediments and soils) and ecotoxicity studies that take these effects into account (Norwegian Pollution Control Authority 2008).

1. Directive 89/391/EEC
2. Directive 2004/37/EC
3. Directive 98/24/EC
4. Directive 89/655/EEC
5. Directive 89/656/EEC
6. Regulation 1907/2006
7. Directive 2008/1/EC
8. Directive 2006/12/EC