Deposition of inhalable particles onto human clothing: A manikin-based chamber study

Clothing has been identified as a potential source of exposure to particulate matter accumulated from human and environmental sources. However, limited studies have investigated the deposition of airborne particles onto worn clothing surfaces. In a controlled chamber, we investigated size-resolved particle deposition (0.2-10 mu m) onto a seated thermal manikin as a function of (i) distinct clothing materials and skin area coverages, including (a) short-sleeve cotton shirt (63 % cotton, 34 % polyester, 3 % elastane), (b) long-sleeve cotton shirt (98 % cotton, 2 % elastane), (c) short-sleeve polyester shirt (100 % polyester), (d) long-sleeve fleece jacket (100 % polyester), and (e) long-sleeve sweater (68 % wool, 32 % polyamide); and (ii) three air speeds (19 cm/s, 26 cm/s, and 33 cm/s). We found that the size-dependent particle deposition loss rate coefficients onto high-roughness clothing material, such as wool/polyamide, were 2-27 % higher than smooth materials, such as cotton. Roughness parameters of clothing were found to be positively associated with deposition loss rate coefficients. As the air speed in the chamber increased, the deposition loss rate coefficient increased. Expectedly, we observed an exponential relationship between deposition loss rate coefficients and particle size. Our results suggest that the type and properties of clothing and air speed are strong determinants of environmental particle uptake by the clothing and could play an essential role in influencing the inhalation exposure of the wearer.