Establishing the safety of novel bio-based cellulose nanomaterials for commercialization

Abstract

In the commercial development of novel nanoscale materials, a proactive approach toward safe commercialization requires assessment of material safety for manufacturing, in product use and for environmental impacts. The goal of this study was to design an industrially-relevant testing strategy and develop key data on lignin-coated cellulose nanomaterials to evaluate their safety before widescale market introduction and subsequent commercialization. The testing plan developed to evaluate BioPlus® lignin-coated fibrils (L-CNF) and BioPlus® lignin-coated crystals (L-CNC) considered a range of potential uses, and employed a variety of standard and tailored protocols to characterize physico-chemical properties, human health effects and environmental fate and toxicity. For human health studies, acute oral toxicity testing as well as dermal and eye irritation studies were completed. Results reveal no oral, dermal or ocular toxicity following L-CNC and L-CNF exposure at the highest doses tested. Testing conducted to evaluate potential environmental effects included aquatic toxicity testing of bacteria (Vibrio fisheri), algae (Pseudokirchneriella subcapitata), invertebrates (Daphnia magna), and vertebrates (Danio rerio). A unique aspect of the study was that in general, testing was performed at environmentally relevant concentrations. Virtually no toxic effects were reported for either L-CNC or L-CNF in these tests, even at artificially high concentrations that could not feasibly occur in the environment. Together with published studies examining the effects of related and conventional substances, these results demonstrate that L-CNC and L-CNF are relatively non-toxic for the broad range of endpoints considered, much like their conventional cellulosic counterparts. These results were anticipated, due to the ubiquity of cellulose in commerce and in the environment, however publication of such negative results is rare, yet critically important to further understanding of the disposition of commercially relevant nanoscale materials.

Current characterization methods for cellulose nanomaterials

“…557 For CNMs, the addition of OM does not appear to have an effect, but the chorion does appear to provide some protection. 558 ISO is in the process of developing a standard method using dechorionated zebrafish embryos. 41 CNMs have been shown to interfere with the invertebrate Daphnia magna test 559 ; a test where organisms get mechanically trapped in the test solution due to an uneven distribution of CNM.…”

Prospective environmental risk assessment of nanocellulose for Europe

“…ref. [51][52][53]. However, the ecotoxicological literature surrounding NC remains scarce, and a number of studies put forward the existence of knowledge and data gaps.…”

Safety Aspects of Bio-Based Nanomaterials

“…The forests constitute a major source of lignocellulosic biomass, a sustainable resource that, in addition, is not competing with food production [ 5 ]. Lignocellulosic materials have long been used in the paper and packing industrial sector, in healthcare products, such as wound healing materials, dialysis membranes, and excipients in tablets, and as rheology modifiers in food products and cosmetic formulations [ 6 , 7 ]. However, the emergence of nanotechnology has opened new and multiple possibilities, not only in the existing industrial sectors, but also for completely novel applications, such as biofuels, aerogels for insulation, vehicles’ components, electronics, or tissue engineering [ 2 , 4 , 6 , 7 ].…”

“…Lignocellulosic materials have long been used in the paper and packing industrial sector, in healthcare products, such as wound healing materials, dialysis membranes, and excipients in tablets, and as rheology modifiers in food products and cosmetic formulations [ 6 , 7 ]. However, the emergence of nanotechnology has opened new and multiple possibilities, not only in the existing industrial sectors, but also for completely novel applications, such as biofuels, aerogels for insulation, vehicles’ components, electronics, or tissue engineering [ 2 , 4 , 6 , 7 ]. The commercial exploitation of nanoscale bio-materials has only begun during the last few years, and although it is currently at pilot-scale for many applications, large-scale commercialization is anticipated [ 4 , 6 ].…”

“…The commercial exploitation of nanoscale bio-materials has only begun during the last few years, and although it is currently at pilot-scale for many applications, large-scale commercialization is anticipated [ 4 , 6 ]. Therefore, companies have a unique chance of being proactive by demonstrating the safety of the emerging bio-based nanomaterials in advance of their commercialization, ensuring that their market potential is not delayed by uncertainties about safety issues [ 4 , 7 ].…”