TY - JOUR
T1 - Aggregation kinetics of diesel soot nanoparticles in artificial and human sweat solutions
T2 - Effects of sweat constituents, pH, and temperature
AU - Li, Jing
AU - Yang, Xingjian
AU - Zhang, Zhen
AU - Xiao, Harry
AU - Sun, Weimin
AU - Huang, Weilin
AU - Li, Yongtao
AU - Chen, Chengyu
AU - Sun, Yan
N1 - Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/2/5
Y1 - 2021/2/5
N2 - Soot nanoparticles (SNPs) are airborne contaminants that could potentially penetrate skin, but their aggregation after contact with sweat may lower their health risks. This study investigated SNP aggregation kinetics in 4 artificial sweat standards and 21 human sweat samples. Effects of sweat inorganic (NaCl, Na2HPO4, and NaH2PO4) and organic (L-histidine, lactic acid, and urea) constituents, pH, temperature, and concentrations were examined. Results showed that SNP aggregation rates in 4 standards followed American Association of Textile Chemists and Colorists (AATCC) > British Standard (EN) > International Standard Organization (ISO) pH 5.5 > ISO pH 8.0, and could be described by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The aggregation rates increased with concentrations of SNPs, inorganic salts, L-histidine, and lactic acid, decreased with increasing pH and concentration of urea, and were weakly influenced by temperature. Systematic characterizations revealed SNP adsorption for organic sweat constituents. SNPs aggregated rapidly to ∼1000 nm in AATCC, but remained stable in ISO pH 8.0 and > 14/21 human sweat fluids over 20 min. The SNP aggregation rates correlated negatively with pH (r = -0.531*) and |ζ potential| (r = -0.464*) of human sweat samples. Sweat evaporation could promote aggregation of SNPs, hence lowering their potential harm via dermal exposure.
AB - Soot nanoparticles (SNPs) are airborne contaminants that could potentially penetrate skin, but their aggregation after contact with sweat may lower their health risks. This study investigated SNP aggregation kinetics in 4 artificial sweat standards and 21 human sweat samples. Effects of sweat inorganic (NaCl, Na2HPO4, and NaH2PO4) and organic (L-histidine, lactic acid, and urea) constituents, pH, temperature, and concentrations were examined. Results showed that SNP aggregation rates in 4 standards followed American Association of Textile Chemists and Colorists (AATCC) > British Standard (EN) > International Standard Organization (ISO) pH 5.5 > ISO pH 8.0, and could be described by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. The aggregation rates increased with concentrations of SNPs, inorganic salts, L-histidine, and lactic acid, decreased with increasing pH and concentration of urea, and were weakly influenced by temperature. Systematic characterizations revealed SNP adsorption for organic sweat constituents. SNPs aggregated rapidly to ∼1000 nm in AATCC, but remained stable in ISO pH 8.0 and > 14/21 human sweat fluids over 20 min. The SNP aggregation rates correlated negatively with pH (r = -0.531*) and |ζ potential| (r = -0.464*) of human sweat samples. Sweat evaporation could promote aggregation of SNPs, hence lowering their potential harm via dermal exposure.
KW - Colloidal stability
KW - Dermal exposure
KW - Nanoscale toxic contaminant
KW - SNPs
KW - Sweat standard
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U2 - 10.1016/j.jhazmat.2020.123614
DO - 10.1016/j.jhazmat.2020.123614
M3 - Article
C2 - 32829227
AN - SCOPUS:85089479935
SN - 0304-3894
VL - 403
JO - Journal of Hazardous Materials
JF - Journal of Hazardous Materials
M1 - 123614
ER -