-
Preservatives
I’m fairly new to cosmetic formulating so purchased Beginning Cosmetic Chemistry (Third Edition) to guide me. This text book indicates that a typical o/w emulsion would have a preservative in the water phase as well as one in the miscellaneous phase. My question is can you use two broad spectrum preservatives such as Optiphen Plus (inci: Phenoxyethanol (and) Caprylyl Glycol (and) Sorbic Acid) and Geogard ECT (inci: Benzyl Alcohol & Salicylic Acid & Glycerin & Sorbic Acid) in the same recipe? The second half to this question would be around preservative usage rate. Would you use the recommended usage rate for each preservative or would you adjust the usage rate because you are combining preservatives?
-
11 Replies
-
Not necessary. However both contain sorbic acid which implies a finished pH of <= 5.5
-
Yes you can combine preservatives, it is not so common however since suppliers usually have lots of effective combinations already available. Regarding the synergistic effects between the two preservative mixtures you mentioned there is no simple answer unfortunately. You need to set up an experimental design in order to find an optimum ratio/concentration.
-
Yes, I had to adjust the ph by adding Sodium Hydroxide as my lotion was on the acidic side. Do you have a personal preference over Optiphen Plus versus Geogard ECT? I’ve been using Geogard ECT in my lotions and facial cleansers and haven’t run into any issues. I have read that Optiphen Plus is a good broad spectrum preservative but can’t find as much information on Geogard ECT.
-
Just letting you know @dsanderson benzyl alcohol tends to break emulsion and has strong odor I would not recommend using this for emulsion batches. I would recommend below ( no parabens):
symdiol 68
mikrokill cos
jeecide cap-5 1 % works really well
euxyl pe 9010
make sure to put some potassium sorbate or sodium benzoate for east and mold ( check ph)
plantservative wsr ( all plant based) -
Hi… is Optiphen actually safe? I am really some scary stuff about it. Female hormone problems, multiple carcinogens, skin irritations, chromosomal changes, etc. The list is long. How can this be acceptable?
Thanks. -
Good Lord. Read credible references. At the allowable rates it is safe. Don’t feed into chemophobia and scare mongering.
-
@SheilaInBoston - “How can this be acceptable?“
This is a great question. The answer is that it’s not. If there was a cosmetic ingredient that caused cancer, chromosomal changes or induced other biochemical changes in the body when used at typical cosmetic levels, it would be illegal to use and sell.
Optiphen (a blend of Phenoxyethanol and Caprylyl Glycol) is safe as used in cosmetics.
Here is a review of the safety testing which you can read for yourself. https://www.evernote.com/shard/s1/sh/9b7aec42-0e69-4833-bf95-2f3901b99792/cc4d8634a61f09eae56ac263a41f98bb
Their conclusion…”On the basis of the available information presented in this report, the Expert Panel concludes the Phenoxyethanol is safe as a cosmetic ingredient in the present practices of use and concentration.”
The remaining question is, why do you think Optiphen causes the problems you mentioned?
-
Perry, that study is quite horrifying…
-
What did you find horrifying about it?
-
What did you find horrifying about it?
My thoughts exactly? @SheilaInBoston
Does the toxicology report scare you? Every substance has its toxic level, even (clean) water. If you read the report thorougly you will see that phenoxyethanol is safe to use in usual concentrations.I would take @Microformulation ‘s advice and only read credible references.
If you want more (unbiased) information on an ingredient, you can check it here for example.
Regarding this topic I would stay away from mommy blogs, EWG and other unsupported scaremongering sites and leave it to people who know what they’re talking about.
Like @Perry mentions above, if phenoxyethanol for example would be carcinogenic or mutagenic, it would have been prohibited a long time ago. -
I will have to echo Perry’s comment and ask what is so horrifying about the CIR abstract. The real take-away is in the summary; “It is concluded that Phenoxyethanol is safe as a Cosmetic Ingredient in the present practices of use and concentration.
The rest of the citation is simply very technically detailed information supporting the assertion. If perhaps you do not have a classical trained background in Chemistry and/or significant experience in Occupational Safety you could be scared by the language. However, a qualified reader would simply see that it is an innocuous ingredient at the approved levels.
Toxicity is dose related. If one takes on a naive perspective of chemophobia, it will be difficult to produce safe products. Preservation serves to provide the client with a product which will be safe throughout the shelf life of the product. In fact, it is dangerous to expose a user to a contaminated product.
Log in to reply.