Exposure to mists may cause eye irritation, as well as upper respiratory tract irritation. Inhalation of the propylene glycol vapors appears to present no significant hazard in ordinary applications. However, limited human experience indicates that inhalation of propylene glycol mists
could be irritating to
some individuals. Therefore inhalation exposure to mists of these materials should be avoided. Some research has suggested that propylene glycol not be used in applications where inhalation exposure or human eye contact with the spray mists of these materials is likely, such as fogs for theatrical productions or antifreeze solutions for emergency eye wash stations.
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Additionally,
some electronic cigarette users who inhale propylene glycol vapor
may experience dryness of the
throat or shortness of breath . As an alternative, some suppliers will put Vegetable Glycerin in the "
e-liquid" for those who are allergic (or have bad reactions) to propylene glycol.