What is Free hydrogen sulfide?
Free hydrogen sulfide (H₂S) is the source of the rotten-egg aroma unique to sulfur springs. Absorbed via both skin and inhalation, it is said to dilate peripheral blood vessels.
Main Effects
- Peripheral vasodilation via skin and inhalationFree hydrogen sulfide is absorbed through both the skin and the respiratory system. This action directly dilates capillaries and other small blood vessels, which can powerfully boost peripheral blood circulation.
- The signature rotten-egg aroma of sulfur springsThis distinct, pungent odor is the defining characteristic of hydrogen sulfide gas. The smell, often compared to rotten eggs, serves as a non-visual cue that you are bathing in a potent, therapeutic sulfur spring.
- Caution required in poorly ventilated bathsIn high concentrations, hydrogen sulfide gas can be toxic. For this reason, proper ventilation in and around the bathing area is legally required to ensure bather safety and prevent the risk of poisoning.
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