Propylene glycol and setting a daily intake limit
What it found
Available data suggest the daily intake limit for propylene glycol could be raised from 25 to 62.5 mg per kg of body weight.
This would apply to both children and adults.
What they found
Studies in people and animals
How it affects blood
When the body can no longer break down propylene glycol fast enough, levels in the blood rise. This can damage red blood cells and cause them to break apart.
Animals and people respond similarly
Animal studies and human data show that animals and people react to this blood cell damage in similar ways. Because of this, the authors say the extra safety margin used for species differences can be reduced.
Other findings
A higher daily limit
By lowering the overall safety margin from 100 to 40, the authors calculate the daily limit could rise from 25 to 62.5 mg per kg of body weight. They say this applies to children and adults.
What the authors conclude
- They argue that the way propylene glycol damages red blood cells is similar across species, so a smaller safety margin is justified.
- Their calculations support raising the daily intake limit from 25 to 62.5 mg per kg of body weight for both children and adults.
How it was done
Propylene glycol is widely used in food, and some estimates of how much people take in approach or go above the current daily limit of 25 mg per kg of body weight. The authors wanted to see if that limit should change based on how the body handles it.
The authors looked at existing animal studies and human data on propylene glycol. They examined how the chemical acts in the body to decide whether the safety margin built into the daily limit could be adjusted.
What it can’t tell you
- We summarised it from the abstract only.
- This work relies on combining past studies rather than running a new trial, so it cannot measure effects directly in a fresh group of people.
- It looks at how limits are set and does not track what happens to people eating propylene glycol over time.
Who paid
- Conflicts
- Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ari Lewis, Steven Boomhower and Charlotte Marsh are employed by Gradient, a private environmental consulting firm. Maia Jack is Chief Science and Regulatory Officer at the American Beverage Association. The work reported in this paper was conducted during the normal course of employment. This work was funded by the American Beverage Association and the International Organization of the Flavor Industry. The authors have the sole responsibility for the writing, content, and conclusions of this article.
- Authors work at
- Harvard University, USA
The paper
- Title
- Considerations for deriving a safe intake of propylene glycol
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Abstract only
- Cite
- Lewis AS, Boomhower SR, Marsh CM, Jack MM (2024). Considerations for deriving a safe intake of propylene glycol. Food and chemical toxicology. doi:10.1016/j.fct.2024.114460PubMed 38325632DOI
Summary written 1 Oct 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error