Health and environmental safety of nanomaterials
Nanotechnology has emerged as a promising new field with numerous applications in the fields of materials science and energy. Nano-sized organic or inorganic ingredients have also been incorporated into thermoplastic or thermoset polymers, generating a new class of materials with improved properties. While nanotechnology has many beneficial applications, the potential impact on the environment and human health of certain nanomaterials is not yet fully understood. Toxicological evaluation has only been performed on engineered nanomaterials generated at laboratory scale, and no information is available regarding their life cycle. The EU-funded 'Nanomaterials-related environmental pollution and health hazards throughout their life cycle' (NEPHH) project worked to identify the environmental impact and health hazards that could result from activities involved in nanostructures. In particular, partners chose to study silicon-based polymer nanocomposites due to their applications in the plastics manufacturing industry. Dust particles from the macro-scale nanostructures were generated in an attempt to recapitulate material released during different life cycle stages simulating vehicle accidents and recycling, amongst other. Given their miniature size, nanoparticles can enter the human body, reach vital organs and cause damage. For this reason, the consortium analysed the potential toxic effects of the released nanosized fraction by in vitro assays. Implications for human health were examined specifically on cell structure and protein expression. Ecotoxicological assessment was also performed on bacteria -at individual level- but also on bacterial biofilms, plants and invertebrates. As a baseline for comparison, composites not integrating selected nanomaterials were used. Results obtained were also compared with the (eco)toxicological risk entailed by pristine nanoparticles, as directly supplied from manufacturers. Several combinations (mainly those polyamide based) revealed certain cytoxic effect. Particularly in the case of montmorillonite integrating polymers, the release of ammonium used as spacer in the montmorillonite is likely to be at the origin of the toxicity. For the ecotoxicological assessment on bacteria, however, it was concluded that, for most samples, the toxicity of polypropylene and polyamide based materials is not related to molecules released from nanomaterial ageing. In the case of terrestrial plants, tested samples elicited no stress symptoms. Complementing these results, a Life Cycle Assessment was performed on a defined application of montmorillonite. Results obtained revealed no significant differences in terms of ecological impacts, whereas the performance of the matrix was increased when the nanomaterial was added. A survey conducted to assess the occupational and environmental health and safety procedures in force in the global nanotechnology sector revealed that nearly half of all involved organisations do not have a specialised nanotechnology safety programme in place. Guidelines for personnel protection and effective waste management of nanoparticle containing materials were developed. For audiovisual material please see: http://webdropoff.cranfield.ac.uk/pickup/c7e4c9c32c4d3a8cfc9effa50d2314f6/267342
