Particulate matter from indoor environments of classroom induced higher cytotoxicity and leakiness in human microvascular endothelial cells in comparison with those collected from corridor.

Academic Journal

Chua ML; Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic, Singapore City, Singapore.
Setyawati MI; Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore City, Singapore.
Li H; Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic, Singapore City, Singapore.
Fang CHY; Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic, Singapore City, Singapore.
Gurusamy S; Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic, Singapore City, Singapore.
Teoh FTL; Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic, Singapore City, Singapore.
Leong DT; Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore City, Singapore.
George S; Centre for Sustainable Nanotechnology, School of Chemical and Life Sciences, Nanyang Polytechnic, Singapore City, Singapore.

Indoor air [Indoor Air] 2017 May; Vol. 27 (3), pp. 551-563. Date of Electronic Publication: 2016 Oct 22.

English

We investigated the physicochemical properties (size, shape, elemental composition, and endotoxin) of size resolved particulate matter (PM) collected from the indoor and corridor environments of classrooms. A comparative hazard profiling of these PM was conducted using human microvascular endothelial cells (HMVEC). Oxidative stress-dependent cytotoxicity responses were assessed using quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and high content screening (HCS), and disruption of monolayer cell integrity was assessed using fluorescence microscopy and transwell assay. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX) analysis showed differences in the morphology and elemental composition of PM of different sizes and origins. While the total mass of PM collected from indoor environment was lower in comparison with those collected from the corridor, the endotoxin content was substantially higher in indoor PM (e.g., ninefold higher endotoxin level in indoor PM 8.1-20 ). The ability to induce oxidative stress-mediated cytotoxicity and leakiness in cell monolayer were higher for indoor PM compared to those collected from the corridor. In conclusion, this comparative analysis suggested that indoor PM is relatively more hazardous to the endothelial system possibly because of higher endotoxin content.
(© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)