Abstract View
Exposure of Adults and Children to the Released and Resuspended Particles from Nanotechnology-enabled Consumer Products
RUIKANG HE, Jie Zhang, Gediminas Mainelis, Rutgers, The State University of New Jersey
Abstract Number: 295
Working Group: Indoor Aerosols
Abstract
Nano-enabled consumer products are becoming an important indoor particulate matter source. The release, deposition, and resuspension of particles from such products could be an important contributor to adverse health effects.
This study investigated personal exposures due to the resuspension of two Ag-based and two Zn-based consumer sprays used indoors. The release and resuspension of particles were investigated in a newly constructed 2.8×1.6×2.4m3 chamber. Particles were sprayed at 1.1m height and then resuspended by a walking adult or the motion of a robotic sampler that simulated a child. The measurements of resuspended focused on particles reaching the breathing zone of an adult (1.5 m height) and child (0.3 m height). Button Samplers (SKC Inc.) with 25-mm PTFE filters (SKC Inc.) were used to collect sprayed and resuspended particles. The mass of captured particles was determined by weighing.
During spraying, the released particle concentration ranged from 350 to 30,000 µg/m3 at 0.3 m and 14 to 14,000 µg/m3 at 1.5 m. The concentrations varied among different products; once the product was sprayed, the concentrations measured at 0.3 m were higher than those measured at 1.5 m at the same time in a vast majority of experiments (94%). When particles were resuspended, resuspension rates ranged from 10-4 to 10-1 h-1, depending on the product, floor type, and experimenter (e.g., adult and child). When particles were resuspended from the carpet, the resuspension rate for particles resuspended by an adult and reaching their breathing zone was higher than for particles resuspended by a child-simulating robot and reaching the child’s breathing zone for 3 of the 4 products. However, when particles were resuspended from vinyl, the resuspension rates measured in the adult’s breathing zone were lower than in the child’s breathing zone. For both the adult and child, resuspension rates were higher for particles resuspended from carpet compared to vinyl.
The results suggest that children could be exposed to higher resuspended particle concentrations when using consumer products compared to adults. The resulting exposures depend on the product, flooring materials, resuspension force, and breathing zone height.