Benzoic acid and its salts: how much is acceptable each day
What it found
Using data on how benzoic acid moves through the body in rodents and people, the authors say the acceptable daily intake could be raised from 0-5 to 0-10 mg/kg body weight.
Human clinical studies found similar handling of the substance in children and adults.
What they found
Studies in people
Children and adults similar
Human clinical studies indicate that the pharmacokinetics of benzoic acid and its salts are similar in children and adults.
No adverse events seen
Human clinical studies found a lack of adverse events in humans at doses comparable to the no observed adverse effect level in rodents.
Studies in people and animals
How the body handles it
Based on pharmacokinetic data in rodents and humans, the authors derived a chemical-specific adjustment factor of 2 for the pharmacokinetic part of the interspecies uncertainty factor.
Factor likely conservative
Additional analyses indicate that the chemical-specific adjustment factor is conservative and that interspecies differences between rats and humans are likely closer to unity.
Possible further reductions
The authors suggest the pharmacokinetic uncertainty factor for intraspecies variability, as well as the pharmacodynamic components of the uncertainty factors, may also be reduced, although they did not calculate to what degree.
What the authors conclude
“In conclusion, the total UF can be reduced to 50 (2 for interspecies differences in pharmacokinetics, 2.5 for interspecies differences in pharmacodynamics, and 10 for intraspecies variability), which would increase the ADI to 0-10 mg/kg body weight.”
Also in their conclusions
- They conclude that the total uncertainty factor can be reduced to 50, made up of 2 for interspecies differences in pharmacokinetics, 2.5 for interspecies differences in pharmacodynamics, and 10 for intraspecies variability.
- They say this would increase the acceptable daily intake to 0-10 mg/kg body weight.
How it was done
The current acceptable daily intake for benzoic acid and its salts as food additives is 0-5 mg/kg body weight, based on a total uncertainty factor of 100 that includes a default factor of 10 for differences between species.
The authors looked at pharmacokinetic data from rodents and humans, and at human clinical studies, to work out a chemical-specific adjustment factor for the differences between species.
What it can’t tell you
- We summarised it from the abstract only.
- The paper does not calculate how far the intraspecies and pharmacodynamic uncertainty factors could be reduced.
- The suggested higher acceptable daily intake is based on modelling of pharmacokinetic data, not on a new feeding trial in people.
Who paid
- Authors work at
- 20 University Road, USA
The paper
- Title
- Pharmacokinetic data reduce uncertainty in the acceptable daily intake for benzoic acid and its salts
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Abstract only
- Cite
- Zu K, Pizzurro DM, Lewandowski TA, Goodman JE (2017). Pharmacokinetic data reduce uncertainty in the acceptable daily intake for benzoic acid and its salts. Regulatory toxicology and pharmacology. doi:10.1016/j.yrtph.2017.07.012PubMed 28720346DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error