The carbopol used is approved for use in food as an ingestible (also in medicinal syrups for infants). It is present as a fraction of a percentage of the total formula content, used only for engaging the liquid into a gel consistency for appropriate and prolonged topical application. The sodium hydroxide is a common ingredient used to buffer pH close to skin pH. As lye, it has been used in soap production for hundreds of years; any health concerns relate to its high pH, not its environmental or body toxicity. It is also only present at a fraction of a percentage point of the total formula, making it safe enough
