Sodium benzoate
Sodium benzoate - dose dependent or straight up toxic?
Sodium benzoate is the sodium salt of benzoic acid It is widely used as a food preservative, a cosmetics preservative, and is also used in pharmaceuticals, and as a treatment for certain metabolic disorders like urea cycle disorders and hyperammonemia due to its ability to bind amino acids and reduce ammonia levels.
in acidic products such as carbonated drinks, fruit juices, salad dressings, pickles, and condiments, sodium benzoate converts to benzoic acid to inhibit the growth of bacteria, yeast, and mold.
The FDA set a maximum safety exposure limit of 5mg per kg body weight per day for consumption of sodium benzoate. It takes 24 hours for sodium benzoate to be processed and excreted out of the body. Sodium benzoate is processed internally the same whether it is by consumption or topical absorption.
How is it processed through the body both dermal and through the GI tract
dermal absorption, sodium benzoate is considered to be metabolized similarly to benzoic acid, with the primary route of metabolism being conjugation with glycine in the liver and kidneys to form hippuric acid. This metabolic process occurs in the mitochondrial matrix, where benzoate is converted to benzoyl-coenzyme A and then to hippuric acid, which is subsequently excreted primarily through the urinary system. Despite the low log Pow value, the rapid metabolism and excretion of sodium benzoate and its metabolites mean that accumulation in the body is not expected. The same metabolic pathway applies to both oral and dermal exposure, and systemic effects can be evaluated together for benzoic acid and sodium benzoate.
Sodium benzoate absorbs through the skin
Source:
Sodium benzoate - Registration Dossier - ECHAn ally
When combined with ascorbic acid (vitamin C) it forms benzene.
Source: https://pmc.ncbi.nlm.nih.gov/articles/PMC4745501/
“Long-term exposure to sodium benzoate may also have cumulative effects on health. While occasional consumption is unlikely to cause significant harm, consistent intake over time could potentially lead to chronic health issues. This is particularly relevant for individuals who consume a lot of processed and packaged foods, which often contain sodium benzoate as a preservative.”
https://synapse.patsnap.com/article/what-are-the-side-effects-of-sodium-benzoate?
European study Absorption through the skin of neonates can create jaundice and skin irritation.
https://www.ema.europa.eu/en/documents/report/benzyl-alcohol-and-benzoic-acid-group-used-excipients-report-published-support-questions-and-answers-benzyl-alcohol-used-excipient-medicinal-products-human-use-emachmp5081882013-and-t_en.pdf
“Researchers found Sodium benzoate to delay the hatching of zebrafish. It also affected the way that zebrafish developed their sense of touch, affected their guts, and had malformed pronephros (basically the kidney of the fish). Another study found that sodium benzoate affected the male reproductive organs of the fish.”
https://pubmed.ncbi.nlm.nih.gov/29842881/
https://pubmed.ncbi.nlm.nih.gov/17644306/
https://pubmed.ncbi.nlm.nih.gov/32911041/
“Sodium benzoate appeared to impair the memory of mice and created oxidative stress in the brain. It also reduced glutathione levels in the brain; glutathione is an important antioxidant in the body. Even short-term exposure to sodium benzoate induced these neurological effects”
https://pubmed.ncbi.nlm.nih.gov/29243862/
Sodium benzoate linked to ADHD: https://pubmed.ncbi.nlm.nih.gov/22538314/
“In one study it increased estrogen levels. It has been found to damage DNA and increase oxidative stress and inflammation. Chronic levels of inflammation have been implicated in hormone-related disorders”
https://pubmed.ncbi.nlm.nih.gov/33646542/
https://pubmed.ncbi.nlm.nih.gov/28229641/
https://pubmed.ncbi.nlm.nih.gov/24693251/
- note that the above is mostly applicable to internal use of sodium benzoate at higher to moderate doses and long term exposure to sodium benzoate internally.
Note that sodium benzoate is processed internally the same from both dermal and internal exposure. So topical applications are applicable to your GRAS daily intake levels and long term exposure.
OTHER SOURCES TO CONSIDER:
https://echa.europa.eu/registration-dossier/-/registered-dossier/14966/7/1
https://bubbleandbee.com/the-honey/?p=is-sodium-benzoate-safe
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9003278/
https://www.healthline.com/nutrition/sodium-benzoate#:~:text=Studies%20suggest%20that%20sodium%20benzoate%20may%20increase%20your%20risk%20of,in%20beverages%20are%20deemed%20safe.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8170748/#:~:text=In%20conclusion%2C%20the%20results%20demonstrate,and%20is%20a%20nephrotoxic%20substance.
https://www.ncbi.nlm.nih.gov/pmc/articles/
https://www.inchem.org/documents/cicads/cicads/cicad26.htm#:~:text=Sodium%20benzoate%20(CAS%20No.,amount%20produced%20worldwide)%20and%20caprolactam.
https://pubmed.ncbi.nlm.nih.gov/21130826/
