Ozone and oxygen
Transdermal delivery
Transdermal delivery means administering a substance across the skin rather than by mouth, injection or inhalation. In an ozone sauna the body below the neck is enclosed in a warm, humid, ozone-containing cabinet while the head stays outside, so ozone reaches skin and not the lungs.
Also called transdermal ozone, transcutaneous ozone, through-the-skin delivery
The design point
The cabinet encloses everything below the neck; the airway is deliberately excluded and the neck opening is covered. That is the whole safety architecture of an ozone sauna.
What happens at the skin
A simple explanation is that ozone “enters through open pores”. The account we now follow, from Velio Bocci, is more specific and more useful:
- Ozone dissolves readily in water, including the thin film of moisture on warm skin.
- Being a potent oxidant it reacts there immediately, preferentially with polyunsaturated fatty acids, and is consumed.
- That reaction produces hydrogen peroxide and a family of lipid oxidation products, and those products, rather than ozone itself, are described as the messengers carrying any downstream effect.
Ozone does not circulate around the body as ozone. It reacts where it lands.
Why steam is part of it
Moist heat raises skin temperature and hydration and increases the permeability of the stratum corneum, the skin’s outer barrier. Our steam studies page collects that research and links on to its sources.
How much reaches the skin
How much ozone a sauna at about 47 ppm delivers into skin over a session has not been quantified, so the 47 ppm figure describes the air inside the sauna rather than a dose.
Why it matters here
It is the reason your head stays outside the cabinet, and the reason the steam is more than a comfort feature: warm, moist skin is what the ozone reacts with.