« Salicylic Acid | Main | Vaseline Sheer Infusion »

Benzoic Acid

Today's Chemical:

Benzoic Acid

EWG Risk Score:


What is it:

Benzoic acid is a weak acid that's used as a preservative.  It's naturally ocurring in many fruits in trace amounts.  The largest natural source of benzoic acid is from the gum of the Chinese Balsam tree, called gum benzoin. Gum benzoin is typically 13-20% benzoic acid. 

Safety Info:

  • Current research has not found it to act estrogenically when ingested (Source) However, see my note below.
  • Some animal tests have shown it to be a developmental neurotoxin at high doses (Source)
  • It is considered safe only at less than a .1% concentration in a finished product (Source)
  • When benzoic acid and vitamin C (ascorbic acid) or citric acid are present, under the right conditions of heat and light, these two ingredients can combine to create the known carcinogen, benzene.   (Source)
  • Sodium benzoate is the sodium salt of benzoic acid, so the safety data for benzoic acid and sodium benzoate are similar. 

Type of products it's in:

Toothpastes, moisturizers, sunscreen, makeup, body wash, mouthwash

Some brands that use this ingredient:

(According to EWG; please review all product labels for up-to-date information) 





Kiss My Face


Nature's Gate

Tom's of Maine

Steph's Opinion:

I am personally still concerned about benzoic acid being a weak estrogen mimicker.  Because of its benzene ring structure, it has the potential to fit in to our body's estrogen receptors.  The studies that showed it wasn't estrogenic was when it was fed to rats, but not applied on their skin.  Parabens aren't estrogenic when you eat them, but are problematic when applied to skin because they interfere with an enzyme called SULT that helps flush estrogen out of the body. Continued application of parabens and other estrogen mimicking chemicals on your skin can actually raise estrogen levels through this mechanism. There have been no studies on the estrogenic activity of benzoic acid when applied to skin, so I still view this ingredient with caution. 

Additionally, it should not be used in a product containing ascorbic acid (vitamin C) and citric acid.  Over time these ingredients can react and form traces of benzene, a known carcinogen. 

NOTE: Benzoic acid is not parahydroxy benzoic acid. 

Parahydroxy benzoic acid looks like this

Benzoic acid looks like this.Notice the parahydroxy benzoic acid contains an additional hydroxyl group (an extra OH group).  Parahydroxy benzoic acid has been studied and is known to act estrogenically.  (Source)  For more about parahydroxy benzoic acid, read our article about Japanese Honeysuckle Extract here.


PrintView Printer Friendly Version

EmailEmail Article to Friend

Reader Comments (20)

are you serious? this is coming from a person who started a line doing research OFF THE INTERNET according to your bio. how can anyone take you seriously, especially after what happened on your facebook? You have no credibility. My husband is a chemist at a very reputable university who has stated that benzoic acid is not an estrogen mimicker. i feel safer buying products from a person who actually does lab research themselves, not from someone who merely copies articles and who has taken advanced chemistry courses. That desn't make you an expert. how do you expect to be taken seriously? what a joke. your customers are being duped.

Mon, April 26, 2010 | Unregistered Commenterlisa

I am just one of many Bubble & Bee customers who trust Stephanie because she offers empirical evidence and the sources. I do not feel that I'm being duped by science.

Mon, April 26, 2010 | Unregistered CommenterDon

Aww how cute! You're first hate comment! (Suddenly everyone is or is related to a chemist)

Anyway, I've been wondering about this one so thanks for addressing it. I noticed it in a couple of brands recently and it doesn't sound AS alarming as other ingredients so it may not be on my biggest avoid list but will when possible.

As always, thank you!

Mon, April 26, 2010 | Unregistered CommenterKathy

@Lisa (most likely aka Daisy) "After what happened on Facebook?" Seriously? You posted more than one fake profile, you personally attacked me and my company several times before you were banned & permanently removed. You have also tried to discredit me here in my own space. This has nothing to do with me, and everything to do with your company trying to hide something. You never answered the question, which, in turn, says volumes about your company. Plus, you're the one that doesn't know the difference between parahydroxy benzoic acid and benzoic acid! And you're saying that I don't know what I'm talking about? That's just silly. I have always and will always cite and link to my sources, online or not. The point is to create content that anyone can research and digest themselves so they may form their own opinion. Sadly, many have formed their own opinions lately about 100% Pure as a company based. I base all of my writings on published and peer-reviewed scientific journals. Just because they happen to be also published online, doesn't mean they're not credible. And, may I point out, that your only defense has been online sources as well.

Also, you're not really reading the articles. I never said that benzoic acid was a known estrogen mimicker. In fact, I said there was no evidence as such. However, because of its molecular structure, it should be studied more. It has never been studied for its estrogenic properties when applied to skin. I stated that under my OPINION heading; it was not presented as fact. I do consider myself to be an expert. I have a vast understanding of chemistry, I have taken several advanced chemistry courses throughout my years, and my degree in English allows me to easily communicate complex studies effectively. And if there's something I don't understand, I research it, instead of making personal attacks on the person that's saying them. If you have issue with facts presented you should take up your issues with the actual information, and not the writer.

And what articles have I copied? You keep saying this, but you have yet to present an example of my doing such a thing.

You continue to divert the subject of 100% Pure containing parahydroxy benzoic acid by attacking me. It is beyond ridiculous at this point.

And furthermore...Chemists should not be formulating "natural" personal care products! If they're that complex, then they're not natural! Technology has no place on my skin! Our products are made by nature, not by scientists. We wouldn't want them to be! One shouldn't have to have an advanced chemistry degree to understand their ingredients label.

You keep trying to bring me down, but I challenge you--bring on the industry chemists! I'll hold my own with them in a scientific discourse. I've done it before, I'll do it again. Instead of trying to discredit me, let's talk science. Let's talk ingredients. 100% Pure, instead of sending your angry PR lady, give me your chemists so we can actually talk about the issue! I'll post a retraction to my original article if a scientific discourse proves otherwise.

@ Don--Thanks so much for your support; I'm sorry that you had to read such negativity. I've really hit a nerve with these industry people, apparently.

Mon, April 26, 2010 | Unregistered Commenter[Stephanie Greenwood]

@Kathy ha ha, thanks, Kathy. You're a peach! An organic one, too! :)

Mon, April 26, 2010 | Registered Commenter[Stephanie Greenwood]

I am honored that you think i am the pr lady. i am not. get your facts straight. i hope they sue the sh#t out of you.

Mon, April 26, 2010 | Unregistered Commenterlisa

You know that when you are being attacked, you must be doing something good! Cudo's to you! And again, thanks for everything you do.

Tue, April 27, 2010 | Unregistered CommenterPatricia Visser

Aw, thanks so much, Patricia. I really appreciate your kind words and support. You're awesome!

Tue, April 27, 2010 | Registered Commenter[Stephanie Greenwood]

"My husband is a chemist"

My husband is an astronaut but that doesn't make me a rocket scientist!

Why don't you try to make a nice bottle of wine with them sour grapes, *Lisa*!

Tue, April 27, 2010 | Unregistered CommenterAppletini VonSmearcampaign

I honestly think 100% Pure has some great products, and I supported them until recently... it's just sad that a company has their head so far up their ass that they don't know how to be adults and communicate effectively about an issue. Instead, they have been hysterical, immature, overly emotional, have not conducted their business in a composed, efficient manner, and have driven away their customers because of this. What I have seen from them is more akin to high-school level cat-fighting. But despite this, you have been the bigger person and have taken the high road, Stephanie. You really know how good, honest business is done. If someone calls you on something, you openly discuss and research it with them. I have never seen you attack anyone at all. It is unfortunate that you've had to deal with a business who chooses to act the opposite. You are a person of great integrity, and that undoubtedly shows through the way you conduct your business. Keep up the good work!

Wed, April 28, 2010 | Unregistered CommenterDiane

You mention the benzene ring structure is what causes the ingredient to be an estrogen mimicker. Just wondering if lavender or tea tree oils have a similar structure? I know you wrote and article a while back about those essential oils, and it doesn't seem like they are truly estrogen mimickers. I assume not. Thanks!

Sun, May 16, 2010 | Unregistered CommenterAmi

You're correct, Ami. These essential oils contain no phenoleic compounds (aka, no benzene rings) that mimick estrogen. This subject comes up frequently--I'll do some more writing on the subject soon.

Sun, May 16, 2010 | Registered Commenter[Stephanie Greenwood]

Stephanie, how dare you use your brain and educate yourself using the internet!? How dare you help people by exposing the deceit of Big Pharma toxins in pseudo "natural" products?! @Lisa, your husband, the chemist, might be late coming home tonight. Also, he tells me the butter was not churned properly last week and he would like you to make INTELLIGENT USE of the internet to research proper butter churning techniques. He further says you need to pedal faster to run the gas generator or he will leave you and stay right here with me. Lawsuit you say? Come at me, bro! :D Sincerely, Jeremiah Philips
PS: Thanks Stephanie for a great resource of TRUTHFUL info!

Mon, January 21, 2013 | Unregistered CommenterJeremiah Philips

I stumbled upon this website while searching for 'Benzoic acid and vitamin C creates benzene' - this site will now be bookmarked. I love that you site peer-reviewed literature - I first learned about this through Gary Null on radio FM 99.5.

The inflammatory comment reminded me of a number of political Facebook pages' comment sections - very negative.

Fri, February 1, 2013 | Unregistered CommenterTerry

To Lisa,

If you were just some person that didn't care about using the personal care products you can buy from the grocery store, you wouldn't be commenting here. If the chemicals stephanie keeps out of her products are just fine for your use, then you would use them and not give a &*^% what other people are buying.

The fact that you get so angry over this is proof to me that you ARE from an industry that is trying to mislead the public. As a person that has multiple autoimmune disorders, no doubt caused by all the toxic chemicals in our environment, I hope they hunt you down and do more than sue you. I hope you suffer much worse than I have as a result of the polluted world you have created.

Oh and I AM a psychologist, so I know what motivates people to behave the way you are on this site. Its called money.

Fri, April 19, 2013 | Unregistered CommenterAnne

I stumbled upon this site looking for info about benzoic acid and acetic acid combination and what obscure reaction that might have. I am a chemist but my forte is inorganic chemistry and metallurgy. Have you done any research on that combination? Apparently there is a recipe going around that women are using this as an exfoliant. Of course I am concerned about inadvertently creating benzene. As for dealing with Lisa, my view with these types who offer criticism and no evidence you usually have to just follow the money to get their motive. If she has valid scientific evidence of her claims she should table it. The FB comment is childish and shows her up for being immature. It never ceases to amaze me how some people think that they can endear themselves to and persuade others by presenting themselves in an antagonistic way. Keep it up Steph, you're OK.

Fri, December 5, 2014 | Unregistered CommenterDrPhil from OZ

What about combining it with Vit C but in a form of Sodium Ascorbyl Phosphate, not ascorbic acid? Is it still dangerous?

Wed, September 16, 2015 | Unregistered Commenterkate

Wow Lisa wow. Kids this is what a hater is. A laid low coward.

Thu, December 10, 2015 | Unregistered Commenterjeff

I was wondering about adding Schizandra to a bath bomb recipe for its vitamin C content and the oleic and linoleic acid content. I've found that schizandra also has benzoic acid in the seeds. I assume since people consume schizandra the benzoic acid is minimal, however since it is a bath bomb formulation, I will be adding citric acid, if this would pose a risk for creating benzene? Basically, I'm not sure if using whole foods as cosmetics is the same as using undiluted chemicals that are in the foods.

Wed, March 9, 2016 | Unregistered CommenterAlex

Guess what else has a benzene ring in them? Tryptophan and tyrosine, amino acids that is abundant in milk, eggs, peanuts, chicken pea, etc. Let’s just starve and never put anything on or in our body because everything is toxic. Chemicals are everywhere, the earth is so dangerous! You know how benzene is made? With heat, light, appropriate solvent and CONCENTRATION of both reactants. If chemical reactions are that easy chemists won’t be struggling producing stuff. PSEUDOSCIENCE ALERT guys!

Sun, March 18, 2018 | Unregistered CommenterWendy

PostPost a New Comment

Enter your information below to add a new comment.
Author Email (optional):
Author URL (optional):
Some HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>