Dermal transfer and environmental release of CeO2 nanoparticles used as UV inhibitors on outdoor surfaces: Implications for human and environmental health

Abstract

A major area of growth for "nano-enabled" consumer products have been surface coatings, including paints stains and sealants. Ceria (CeO) nanoparticles (NPs) are of interest as they have been used as additives in these these products to increase UV resistance. Currently, there is a lack of detailed information on the potential release, and speciation (i.e., ion vs. particle) of CeO NPs used in consumer-available surface coatings during intended use scenarios. In this study, both Micronized-Copper Azole pressure-treated lumber (MCA), and a commercially available composite decking were coated with CeO NPs dispersed in Milli-Q water or wood stain. Coated surfaces were divided into two groups. The first was placed outdoors to undergo environmental weathering, while the second was placed indoors to act as experimental controls. Both weathered surfaces and controls were sampled over a period of 6months via simulated dermal contact using methods developed by the Consumer Product Safety Commission (CPSC). The size and speciation of material released was determined through sequential filtration, total metals analysis, X-Ray Absorption Fine Structure Spectroscopy, and electron microscopy. The total ceria release from MCA coated surfaces was found to be dependent on dispersion matrix with aqueous applications releasing greater quantities of CeO than stain based applications, 66±12mg/m and 36±7mg/m, respectively. Additionally, a substantial quantity of CeO was reduced to Ce(III), present as Ce(III)-organic complexes, over the 6-month experimental period in aqueous based applications.

Size and Surface Charge Dependent Impregnation of Nanoparticles in Soft- and Hardwood

“…These elements pose a structural limitation, and therefore larger particles are not expected to penetrate the wood structure due to the clogging of conducting pathways [15,17]. The latter is in line with recent findings of MC-based wood impregnation; it was shown that most of the copper particles were deposited on the wood surface since the larger particles (the bulk of the material consists of larger micron size particles [24]) could not penetrate the wood [13,24].…”

Release and transformation of ZnO nanoparticles used in outdoor surface coatings for UV protection

“…(Hanus and Harris, 2013;Keller et al, 2013;Teizer et al, 2012;van Broekhuizen et al, 2011) NPs used in surface coatings are an important area of study, as the nature of their application (i.e., at the product surface) drastically increases their environmental contact, potentially accelerating their transformation and release. (Clar et al, 2018) Few studies have examined the conditions that encourage transformation and release of NPs from such coatings. Previous research regarding the release of NPs from surface coatings focused on passive release conditions including leaching and façade runoff.…”

Study on polyurethane‐acrylate/cerium dioxide modified by 3‐(Methylacryloxyl)propyltrimethoxy silane and its UV absorption property

“…CeO 2 is widely used in the chemical mechanical polishing, electrochemistry and ultraviolet coating for its high polishing accuracy, good chemical stability, and excellent UV absorption property 16–20 . Due to its small particle size and high activity, it can reflect and scatter ultraviolet rays as well as absorb them, and thus it has a good shielding ability to ultraviolet light, and prevents the polymer from aging 21,22 . Therefore, it is used to modify polymers.…”