Application of Direct Analysis in Real Time-Mass Spectrometry to the Study of Oxidation of Skin Oil Components with Indoor Ozone

摘要

1. This investigation is the first mass spectrometry study of the chemical changes occurring in the condensed phase when skin oil is exposed to ozone; 2. This work shows that the oxidative transformation of skin oil components is rapid with a lifetime of 10 minutes with 50 ppb ozone with the formation of a suite of highly oxygenated species, composed of carboxylic acids; 3. Pyroglutamic acid is not reactive with ozone which may make it useful as a tracer of human contamination indoors; 4. These results imply that the oils covering human skin and those deposited to indoor surfaces are being continually oxidized under ambient conditions, with a mixture of both endogenous components alongside their heterogeneous oxidation products; 5. It will be important to determine the toxicological properties of the oxidation products given earlier work that has indicated that squalene oxidation gives rise to redox-active condensed-phase materials and gas-phase products that are irritants.