Abstract
This study was carried out to test the hypothesis that nanogold particles can accumulate in the olfactory bulb, and translocate from the lung to other organs after inhalation exposure. Gold nanoparticles were aerosolized and introduced through an exposure chamber. The number concentration of airborne nano-sized particles was 2×106 #NSPs/cm3 with >75% of particulates between 30 and 110 nm. Exposure for 5 days resulted in significant increase of Au in the lung and olfactory bulb as detected by ICP-MS, but after 15 days, significant accumulation of gold was detected in the lung, esophagus, tongue, kidney, aorta, spleen, septum, heart and blood. Microarray analysis showed downregulation of many genes related to muscle in the nanogold-exposed lung. Lipidomic analysis of the lung showed a specific decrease in phosphatidylserine 36:1 species. We conclude that nanogold is able to translocate from the lung to other organs with time, and causes significant effects in exposed tissues.
Acknowledgements
The authors would like to thank the Office of Life Sciences and NUS Environmental Research Institute for seed funding, and the NUS Nanoscience and Nanotechnology Initiative for administrative support. Ms Li-Yen Lee and Hui-Jen Lye provided expert help in Affymetrix microarray analysis. Prof. Jost O. L. Wendt for stimulating discussion at the inception of this work. There are no conflicts of interest.