Propyl Gallate vs Dimethylpolysiloxane: which is worse?

What is Propyl Gallate?

Propyl gallate is a synthetic antioxidant preservative derived from gallic acid and propanol. It prevents oxidation of fats and oils, extending shelf life of fat-containing foods. It is often used in combination with BHA and BHT for synergistic antioxidant effect. Chemical formula: C10H12O5.

What is Dimethylpolysiloxane?

Dimethylpolysiloxane (PDMS, polydimethylsiloxane) is a silicone-based polymer used as an antifoaming agent in food and beverages. It prevents the formation of foam during food manufacturing and cooking. It is the same base material used in silicone cookware, medical devices, and contact lenses.

Documented risks

Propyl Gallate: Animal studies have shown propyl gallate may cause liver damage at high doses. Concerns about estrogenic activity have been raised — some studies suggest propyl gallate may weakly mimic estrogen. Contact dermatitis and allergic reactions are documented in both food and cosmetic applications. Japan banned propyl gallate for food use as part of its precautionary approach to synthetic food preservatives. NTP bioassays found dose-dependent liver effects. EFSA's re-evaluation set an ADI of 0.1 mg/kg body weight — one of the lowest ADIs for food additives, reflecting toxicological concern.

Dimethylpolysiloxane: Dimethylpolysiloxane is generally considered non-toxic. It is not absorbed by the gut and passes through the digestive system unchanged. The FDA permits it at up to 10 ppm in cooking oils. EFSA's evaluation found no evidence of toxicity at permitted food use levels. There are no established cancer or reproductive toxicity concerns with PDMS at food use concentrations. The compound is the same base polymer used in many safe medical applications including contact lenses and breast implants (though the medical grade is different purity). The main environmental concern is PDMS persistence in the environment, as it is not readily biodegradable. Primary consumer concern is psychological rather than toxicological: the fact that it is used in both McDonald's frying oil and Silly Putty (which also contains PDMS) generates public attention, but the chemistries are actually different grades of the same polymer family.