Is Grapefruit Seed Extract Safe?

Grapefruit Seed Extract's initial controversy many years ago lie in its potential to be contaminated with benzalkonium chloride, parabens, and triclosan.  Numerous studies have tested samples of commercially produced GSE and found these contaminants to be present.  (See here, here, here and here.)  The biggest contaminant found is benzalkonium chloride, a chemical that rates a 5 in the cosmetics database that's a known immune system toxin, skin toxin, and potential endocrine disruptor. 

Some studies have shown that without these contaminants, a truly natural extract of grapefruit seed and pulp in ethanol or glycerin, had no antibacterial properties.  However, GSE apologists claim that GSE can be effective without these contaminants.  So, what is the truth? Is there such thing as a "pure" GSE, and if so, is it effective?

Grapefruit Seed Extract was first developed in 1972 by a man by the name of Dr. Jacob Harich.  Today, there is one main manufacturer of GSE that defenders claim is pure.  It is sold under the name Citricidal. This website describes how it is made:

1. Grapefruit pulp and seed is dried and ground into a fine powder.
2. The powder is dissolved in purified water and distilled to remove the fiber and pectin.
3. The distilled slurry is spray dried at low temperatures forming a concentrated flavonoid powder.
4. This concentrated powder is dissolved in vegetable glycerine and heated.
5. Food grade ammonium chloride and ascorbic acid are added, and this mixture is heated under pressure. The amount of ammonium chloride remaining in finished Citricidal is 15-19%; the amount of ascorbic acid remaining is 2.5-3.0%.
6. The ammoniated mixture undergoes catalytic conversion using natural catalysts, including hydrochloric acid and natural enzymes. There is no residue of hydrochloric acid after the reaction.
7. The slurry is cooled, filtered, and treated with ultraviolet light.

As you can see, this isn't a natural process, it being treated with hydrochloric acid and ammonium chloride. After all the chemical reactions occur, the final composition of the extract is made up of about 60% diphenol hydroxybenzene, (information sheet provided from the manufacturer here) a chemical classified as a quaternary ammonium chloride -- the same as benzethonium chloride.  In fact, it is nearly chemically identical to benzethonium chloride. This is one possible reason that lab tests have shown GSE to be "contaminated" with benzethonium chloride, because diphenol hydroxybenzene is so chemically similar. 

Typically, when a truly natural extract is made, plant matter is let to steep in a solvent such as water (as in making tea), in alcohol (like the vanilla extract you'd use in baking), or in glycerin (like with many herbal supplements you'd find at the health food stores) to extract the plant's beneficial or desirable compounds, whether it be a flavor, smell, or antioxidant. It's a one or two step process that doesn't involve other chemical processing or solvents. GSE is clearly not a natural extract, but a synthetic ingredient, considering it goes through 7 steps of processing and the extract doesn't retain the original compounds present in grapefruit.

Sometimes you'll see claims of different GSE brands being made from organic grapefruit.  But, whether it's organic grapefruit or not, the extract is still going to contain diphenol hydroxybenzene due to its manufacturing process. You might also see "Soil Association Certified Organic" GSE, but note this is not a certified organic product according to USDA standards. The Soil Association is a European organic standard, and the requirements are much less strict than that of the USDA. They will allow and certify a synthetic chemical like GSE if it meets certain criteria for biodegradability, aquatic toxicity and bioaccumulation. So, since the grapefruits were organically grown, and it meets their requirements, they approve the extract as "organic," even though it's a synthetic chemical. The Soil Association also approves phenoxyethanol as a preservative ingredient as well. The USDA will not certify GSE, or allow it in a certified organic product. If you see a product bearing USDA certified organic claims but contains GSE, it is illegally labelled. GSE is not on the USDA's list of approved non-organic substances (they allow a few non-organic ingredients like vitamin E in to their products).    

So, let's take a look at diphenol hydroxybenzone.  Why exactly do we want to avoid it?

The problem that I see with diphenol hydroxybenzene is the fact that on a molecular level, it's full of benzene rings.  The name "diphenol" means that there are two phenol groups. Phenol is a benzene ring with one hydrogen and one oxygen molecule. Chemicals with benzene rings are particularly worrisome in personal care products because once they enter the bloodstream they can mimic the hormone estrogen. Estrogen is primarily made up of benzene rings, and our estrogen receptors are made to "fit" benzene rings. So, when a chemical with a benzene ring enters the body, it has the potential to lock up in the estrogen receptor and can stimulate it. Estrogen mimickers also have the potential to raise levels of estrogen by inhibiting the function of an enzyme called SULT1E1, that helps to remove estrogen from the body. 

The strange thing with diphenol hydroxybenzene is that there are no chemical diagrams provided by the manufacturer (or anywhere, even in organic chemistry guides), and the name of the chemical doesn't help (as it should) in finding its chemical structure.  Hydroxybenzene is just another name for phenol, so the name means "2 phenol phenol," which is weird.  My guess is that it's a simplified name for the chemical.  The manufacturer does say that hydroxybenzene is nearly identical to benzethonium chloride, which looks like this:

The two hexagonal rings you see in the structure are the problematic benzene rings that I was talking about.  Benzethonium chloride has been found to be even more toxic than triclosan. (Source) It also carries the risk of being a strong skin irritant, and it showed tumor formation at moderate doses. However, in its defense, according to National Toxicology Program studies, it exhibited no evidence of carcinogenic activity or endocrine disruption in a two-year rat and mouse study. This study did, however, show that the animals treated with benzethonium chloride did have increased inflammation in the body and a slightly lower survival rate than the control group.

The bottom line is that while there is conflicting evidence of the other negative health effects of benzethonium chloride (and the diphenol hydroxybenzene present in GSE), at the very least it's a skin irritant that increases inflammation in the body. My personal opinion on it is that it is safer than other preservatives. However, if you prescribe to an organic mindset and lifestyle, you will want to avoid Grapefruit Seed Extract, for it is nothing other than a synthetic chemical.

Note: Grapefruit essential oil is natural, and not the same thing as Grapefruit Seed Extract.