METAS has produced reference soot aerosols (uncoated soot particles and soot particles with organic coating at various sizes). A total of three measurement campaigns were conducted at METAS. In each measurement campaign, human epithelial cells were exposed to the aerosols and the cytotoxicity was quantified. The NACIVT (Nano-Aerosol Chamber for In Vitro Toxicology), which simulates the human respiratory tract, was used for the exposure studies. The aerosol dosage could be adjusted. The study showed that:
i) carbon black particles with a high elemental carbon content do not exhibit cytotoxicity
ii) the cytotoxicity depends on the "thickness" of the organic coating.
The analyses with ion chromatography have shown that the organic coating contains several organic acids. Some of them could be identified with standards. The definitive identification will be carried out within the framework of AeroTox using IC-MS.
