Ozone Interactions with Human Hair: Ozone Uptake Rates and Product Formation

In the 2008 study, researchers investigated how ozone interacts with human hair, specifically looking at the uptake of ozone and the production of volatile aldehydes and ketones. They found that unwashed hair, particularly near the scalp, had the highest ozone uptake and reaction probability due to scalp oils, indicating these oils play a significant role in ozone reactivity. The study involved eight hair samples, both washed and unwashed, which were exposed to ozone for 24 hours. The mean integrated ozone uptake was 5.1±4.4 μmol O3 g−1, with initial and final reaction probability values of (13±8)×10−5 and (1.0±1.3)×10−5, respectively. There was no significant difference in ozone uptake between washed and unwashed hair, but unwashed hair more frequently emitted compounds like geranyl acetone and decanal, which are associated with ozone reacting with sebum. The aldehyde yields ranged from 0.00 to 0.86. The study concluded that the ozone flux to skin and hair is likely nearly transport limited, which could reduce personal ozone exposure but increase exposure to its reaction products.