[Doreen]

@zaidjeber
It only happens with l-ascorbic acid, not with the esters. It’s also %-dependent (from 15 to 20%), whether it’s an expensive brand or self-made. Many people think they’re dealing with an oxidized product, but the serum itself shows no discoloration or weird smell.

[Doreen]

Hi Nitrick,

I make my own (leave-on) anti-transpirant cream with 5% aluminum chlorohydrate. The cream seems way more effective than the aerosols/sprays that I’ve used with it.
The ingredient can be sold at MakingCosmetics for example.
It’s not effective in a wash (rinse-off) though.
(As a cheaper solution you can also use simple (potassium) alum, but it gives a very acidic solution, making it more irritable.)

[Doreen]

@jackleon80s

Is there an advantage in placing the ingredients into the water phase before emulsion?

Allantoin is heat stable and dissolves better at higher temperatures, so you can add it in the water phase. Up to 0,5% will not precipitate once the emulsion is cooling down.

About the herbal extracts: which one do you use? Perhaps if you give names, people can help you better (e.g. licorice extract).

[Doreen]

@DRBOB@VERDIENT.BIZ
But sucrose may be reacting with glutamate (amine portion) causing Mallard reaction and browning just like roasting a turkey and if so you have to delete one or the other  sucrose?? Also check RT samples as Mallard reaction does not need a catalyst:however heat accelerates it.

Just like my vitamin C serum: reducing sugar (l-ascorbic acid) + amine portion (like l-tyrosine etc in skin) + a bit of skin warmth as catalyst? = a slight orange/brown skin discoloration + metallic smell: Maillard reaction! Thanks to @johnb I finally figured out what so many of us with a high % vitamin C (15-20%) product are experiencing! Nasty smell and discoloration.
The serum itself wasn’t changing colour, because there were no amino acids in it, but it obviously started reacting with amino acids in the skin!

[Doreen]

@Microformulation
Ok, thank you for explaining it!

[Doreen]

@Microformulation
Interesting article!
These boosting agents, ethylhexylglycerin for example, do they make the PE more effective on the microbes that are already sensitive to it?
The explanation on the site of Lotioncrafter got me thinking it is especially effective on gram negative bacteria, but reading this article, it seems the other way around.
Thanks!

[Doreen]

@David
Wow, the status has been changed as we speak, this month! Thanks for the link, it was a bit confusing.

@Belassi
I’m also astonished how animal health seems irrelevant in this…
I’m glad to read your dogs are doing better, hopefully they all will fully recover very soon.

[Doreen]

@Belassi
The strange thing about the links in your first post: the article is brand new, but regarding MIT it refers to an old journal of the European Union (2009), which shows restrictions indeed. The recent one from 2017, however, shows no restrictions at all and just names MIT as an accepted preservative.

^ I didn’t read the second part of Bill’s answer well enough, I assumed the restrictions were still valid.

How are your dogs doing at the moment? I hope the improvement you mentioned has been speeding up.

[Doreen]

@ozgirl
I see there’s nothing about MIT being restricted in leave-on products, though it is a recent list. Strange. Maybe due to the forementioned voluntary decision?

@Belassi
Do you know the % in the Hartz product?

[Doreen]

Hi Bindu,
What are the other ingredients in this formula? Maybe the sticky feeling is caused by another ingredient?

[Doreen]

@zaidjeber
You’re right, higher levels can be recommended by suppliers, but their suggestions aren’t always practical or useful…

BHT is a stronger anti-oxidant than vitamin E, I haven’t worked with it in cosmetic preparations. The reason I’m mainly focusing on vitamin E is because of its supposed benefits on skin, besides preventing rancidity. I’m also sure johnb can give you a lot more information on it, but I suspect he might be on vacation. I’m also sure @Belassi ^ knows way more on this than I do.

[Doreen]

Allantoin 1%? I’ve had precipitation problems at higher levels than 0,5%. How do you keep it solubilized?

I’m curious about the 1% tocopherol: which type do you use and why in this %? There is controversy about tocopherols and their esters and pro-oxidation in higher %. In the Journal of the American Oil Chemist’ Society they advise between 0,03 and 0,06% as anti-oxidant.

I’m still waiting for the experts here to give an opinion on it.
(https://chemistscorner.com/cosmeticsciencetalk/discussion/3325/tocopherol-questions-for-cosmetic-scientists#latest)

[Doreen]

they are still permitted in Europe, but they’re restricted to rinse-off products only 

True, cosmetics manufacturers, joined in Cosmetics Europe, voluntarily decided to ban MIT in (leave on) skin care products and wet wipes. Dermatologists had a great influence in this decision.
MIT is used in a lot of rinse-off products here. In a concentration up to 0,01% is allowed.

[Doreen]

You’re welcome. Until your post I didn’t even know of the existence of cosmetic vaginal suppositories!
Personally I wouldn’t like a strong ethereal oil like tea tree or ‘tropical splash deodorant’ in this delicate area as our vaginas are lined by a variety of glands that produce the fluids needed to both lubricate and cleanse. I can only believe products like these will disrupt the natural present flora.
I do however believe in using a mild low pH soap on the labia, but I don’t see any use for the vaginal cavity.

As being a woman, I can imagine names like ‘tropical splash’ can make one enthousiastic, but at the end these brands only jump in on our feelings/insecurities and do not really care about our genital health.

I also wouldn’t rely on the so called ‘gynaecologist tested’ claim.
Most gynaecologists strongly advice not to use these products.
Perhaps it’s an idea to ask your own gynaecologist about his/her opinion on this? 

I’m sorry that I can’t be of any help to you. Maybe there are other people here who can.
Good luck anyway!

[Doreen]

This has been very helpful to me. Here you can read that especially botanicals like Aloe are sensitive to microbial growth.

I do think you need to mention all the preservatives, as they all will be present in a certain % in your formula if you use them both.
Maybe this is helpful.

[Doreen]

@pradeep @em88
Sorry Pradeep, my mistake, I didn’t read well!

[Doreen]

Products that are intended to be ingested, injected or placed in contact with other parts of the
human body e.g. the mucous membranes of the nasal passage or the internal genitalia cannot
be considered to be cosmetic products. (Source)

[Doreen]

@em88
The 90% mentioned isn’t the efficiency rate, but the % used in his/her formulation!

[Doreen]

@MarkBroussard @johnb
After I did some testing it seems that potassium sorbate is the culprit indeed!
Obviously its peripheral vasodilating effect is especially noticeable when the skin is already irritated. If the skin isn’t (at least not visible) irritated, I now and then just sense a slight warm glow.

[Doreen]

@DRBOB@VERDIENT.BIZ
You can add the SB at the end of the process after you adjust PH with CA.

This is also how I do it with potassium sorbate, I expected precipitation problems with it because of its formation to sorbic acid in the acidic CA environment, as the sorbic acid also is only slightly water soluble.

[Doreen]

@Belassi
How are the results so far with the cofffee shampoo (the one with licorice)?

[Doreen]

Vaginal suppositories with cosmetic claims?!?! 
Suppositories, vaginal or otherwise, always have a lipophilic base, (like Witepsol H15) to suspend the pharmaceuticals in. These are solid fats. I only have experience with these. I can’t think of another reason why one would want these lipids in the vagina, than strictly pharmaceutical reasons (inducing labour etc).

[Doreen]

What about ketoconazole? In this country up to 1% can be used in cosmetics, 2% for pharmaceuticals.

Edit: Sorry, I see this is a very old thread.

[Doreen]

If you do not want your customers to get severe eye infections, well… yes.

[Doreen]

@johnb
It can be a bit confusing sometimes, I don’t always see in time that it’s old. But you’re right! Your answer came in handy for myself aswell (SA solubility finding out by experimenting).