Assessment of Nanoparticle Release from Polyamide 6-and Polypropylene-Silicon Composites and Cytotoxicity in Human Lung A549 Cells

The steady increase in application of nanoparticles in novel products over the past decade has triggered concerns about the impact of nanoparticles on human health. This study assessed the release of nanoparticles from polyamide 6 (PA6)- and polypropylene (PP)-silicon composites during drilling test and tested the toxicity of the released nanoparticles. The PA6 and PP polymers and their respective polymer-silicon composites, each containing 5 wt% of nano-fillers (silica nanoparticles, organically modified montmorrillonite) or larger fillers (glass fiber or foam glass crystal materials) were studied. It was shown that PA6-based materials generated up to ten times more nanoparticles than the PP-based materials. The polymer-silica nanocomposites generated the highest amount of nanoparticles, whilst the polymer-montmorrillonite composites and neat polymers generated the least. In human lung epithelial A549 cells, the toxicity for PA6-based nanoparticles appeared to be higher than PP-based nanoparticles. This study suggests that the assessment of nanoparticle release integrated with a nanoparticle toxicity study could reveal the potential risk of human exposure at certain stages of the product life cycle and the development of safe products.