Since my original post on Grapefruit Seed Extract, I’ve stumbled upon some new eye-opening information, so I thought I’d expand the subject here.

The big controversy that’s been going on for years with Grapefruit
Seed Extract lies 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 7 in the cosmetics database that’s a known immune system toxin, skin toxin, and possible cancer risk.

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 truly 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, 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–the equipment possibly
misread the diphenol hydroxybenzene.