The Release of Nanosilver from Consumer Products Used in the Home
Nanopure water (MilliQ, Billerica, MA) was loaded into two humidifiers, and the mist was collected and analyzed for total silver content. The mist was pulled through a stainless steel ultraviolet lamp housing column (3.2-cm diam. by 31.5 cm, Millipore, Billerica, MA) packed with 5-mm-diam. borosilicate glass beads (VWR, West Chester, PA) by connecting a 1/4-HP vacuum pump (VWR, West Chester, PA) with Tygon R-3603 tubing (VWR, West Chester, PA). During vacuum pump operation, the airborne water droplets attached to the surface of the beads. Intermittent stopping of the vacuum pump allowed the water to fall out of the bottom of the column for collection. A schematic of the apparatus is supplied in the Supplementary Information (Supplementary Fig. S5). Eight mist samples (15 mL each) were collected from the small humidifier. A composite mist sample (500 mL) was collected from the large humidifier and concentrated to 50 mL for analysis because of low silver content.