Migration of Ag- and TiO₂-(Nano)particles from Textiles into Artificial Sweat under Physical Stress: Experiments and Exposure Modeling

Abstract

Engineered nanoparticles (ENP) are increasingly used to functionalize textiles taking advantage, e.g., of the antimicrobial activity of silver (Ag)-ENP or the UV-absorption of titania (TiO2)-ENP. Mobilization and migration of ENPs from the textile into human sweat can result in dermal exposure to these nanoobjects and their aggregates and agglomerates (NOAA). In this study we assessed exposure to NOAA migrating from commercially available textiles to artificial sweat by an experimental setup that simulates wear-and-tear during physical activity. By combining physical stress with incubation in alkaline and acidic artificial sweat solutions we experimentally realized a worst case scenario for wearing functionalized textiles during sports activities. This experimental approach is not limited to NOAA, but can be used for any other textile additive. Out of four investigated textiles, one T-shirt and one pair of trousers with claimed antimicrobial properties were found to release Ag <450 nm in detectable amounts (23-74 μg/g/L). Textiles containing TiO2 for UV protection did not release significant amounts of TiO2 <450 nm, but the antimicrobial T-shirt released both TiO2 and Ag <450 nm. The silver was present in dissolved and particulate form, whereas TiO2 was mainly found as particulate. On the basis of our experimental results we calculated external dermal exposure to Ag and TiO2 for male and female adults per use. For silver, maximal amounts of 17.1 and 8.2 μg/kg body weight were calculated for total and particulate Ag <450 nm, respectively. For TiO2, the exposure levels amount to maximal 11.6 μg/kg body weight for total (mainly particulate) TiO2. In comparison with other human exposure pathways, dermal exposure to NOAA from textiles can be considered comparably minor for TiO2-NOAA, but not for Ag-NOAA.

Release of nanomaterials from solid nanocomposites and consumer exposure assessment – a forward-looking review

“…Recent studies have shown that Ag NP-containing textiles can release significant quantities of Ag in water (Benn and Westerhoff, 2008;Benn et al, 2010;Pasricha et al, 2012), washing liquid (Geranio et al, 2009;Lorenz et al, 2012;Impellitteri et al, 2009), and artificial sweat (Kulthong et al, 2010;Geranio et al, 2009;von Goetz et al, 2013a).…”

“…A number of studies have attempted to mimic one of the possible real-life scenarios of nano-Ag textile use by immersing the fabrics into artificial sweat at body temperature (Kulthong et al, 2010;von Goetz et al, 2013a;Yan et al, 2012;Stefaniak et al, 2014). The quantities of Ag released varied substantially for different fabrics and pH values, and was most likely dependent on the amounts of silver in fabrics, the fabric quality and the composition and pH of artificial sweat applied.…”

Scalable and Environmentally Benign Process for Smart Textile Nanofinishing

“…In addition, if uncontrolled evaporation of the solvent occurs during the drying process, it can cause inhomogeneous distribution of NPs on the fibers due to migration phenomena. 16 This drying procedure also limits the roll-to-roll speed of the textile finishing line. Another drawback of the wet-finishing process is that the reproducibility and controllability of nanomaterial deposition are frequently inhibited by the batch-type operation.…”

Potential risks and benefits of nanotechnology: perceptions of risk in sunscreens

“…In the US, in contrast, the use of nanosilver in food containers is possible (EPA 2010, von Goetz et al 2013), but has to be registered.…”