Well, inform them that PG is considered safe by the FDA.
There is no workplace or environmental standard for propylene glycol. FDA considers an average daily dietary intake of 23 mg/kg of body weight to be safe for persons 2-65 years of age (Agency for Toxic Substances and Disease Registry 1997).
Propylene glycol is used in various foods, cosmetics, and pharmaceutical products.
Propylene glycol toxicity is not expected in normal environmental or occupational exposures.
Propylene glycol toxicity is metabolized to compounds that are normal constituents of the citric acid cycle.
Large doses and unusual circumstances are necessary for the development of propylene glycol toxicity.
Propylene glycol poisoning is marked initially by CNS depression and an elevated osmolal gap and, later, by an increased anion gap.
Unlike ethylene glycol, propylene glycol does not produce nephrotoxicity in humans.
Treatment for propylene glycol poisoning is supportive. It may involve correction of metabolic acidosis using sodium bicarbonate therapy and, for severe cases, hemodialysis.
More infor on it at:
Ethylene Glycol and Propylene Glycol Toxicity: What is Propylene Glycol | ATSDR - Environmental Medicine & Environmental Health Education - CSEM
Okay so in rare, unusula cases it can be toxic, so can water - still far better tha cigarettes and, I'd wager that most people encounter it daily and don't even realize it.
