Computer modeling of OH reactivity (L) and concentration (R). (Zannoni et al., Science, 2022)
There are all kinds of pollutants in the air around us. Outdoors, these can be washed away through the falling rain, and the oxidation that happens after ultraviolet light from the Sun interacts with ozone and water vapor.
So, what happens indoors?
As a new study shows, there's also some oxidation going on indoors too: the chemical cleaning that occurs via these hydroxyl (OH) radicals – short-lived reactive species whose job is to oxidize other molecules – happens through a combination of ozone leaking in from the outside, and from the oxidation fields that we create around ourselves.
In some scenarios, levels of OH radicals indoors are comparable to daytime outdoor levels, scientists have found. In other words, we're walking, breathing, chemical reaction machines, which has implications for indoor air quality and human health.
"The discovery that we humans are not only a source of reactive chemicals, but we are also able to transform these chemicals ourselves was very surprising to us," says atmospheric chemist Nora Zannoni from the Institute of Atmospheric Sciences and Climate in Italy. READ MORE...