According to the WHO, the acceptable limit is 25 milligrams of propylene glycol per kilogram of your body weight. In the U.S., the average exposure is about 34 milligrams per kilogram of body weight.

The World Health Organization recommends a maximum intake of 11.4 mg of propylene glycol per pound of body weight per day. The estimated exposure to propylene glycol through foods in the US is 14 ...