Cytotoxic and Inflammatory Effects of Coarse and Fine Particulate Matter in Macrophages and Epithelial Cells

Abstract

The purpose of our study was to determine the cytotoxic and inflammatory effects of aqueous suspensions of coarse (10–2.5 µm) and fine (<2.5 µm) particulate matter (PM) in NR8383 macrophages and A549 epithelial cells. Weekly samples from four differently polluted locations in Germany were tested at equal mass for lactate dehydrogenase leakage, nitric oxide (NO) production by NR8383 cells and interleukin-8 (IL-8) release from A549 cells. Significant toxicity was observed with coarse PM but not with fine PM in the NR8383 cells as well as the A549 cells. Both fine and coarse PM were found to cause NO production. Coarse PM from all locations caused a significant increase in IL-8 release, whereas for fine PM significant IL-8 release was only observed with samples from the most polluted (industrialized) location. Irrespective of the sampling locations, coarse PM showed stronger NO production and IL-8 release than fine PM. In conclusion, our date indicate a major contribution of the coarse fraction to the toxicity and inflammatory effects of PM in vitro.