Instability and Safety of Homemade Cream/Lotion Mixtures

Question

I mixed the following ingredients into two different finished products:

For face cream:

Pond's cream sachet 2
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/147-%E0%B8%81%E0%B8%A3%E0%B8%94%E0%B9%82%E0%B8%88%E0%B8%88%E0%B8%B4%E0%B8%81-kojic-acid-dipalmitate.html:jgbzojaw]Kojic Acid Dipalmitate[/url:jgbzojaw]
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/134-vitamin-c-l-ascorbic-acid-%E0%B8%9C%E0%B8%87%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%8B%E0%B8%B5.html:jgbzojaw]Vitamin C (L-ascorbic acid)/url:jgbzojaw
Mild Preserved Eco(TM)(Preservative-Free)
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/68-alpha-arbutin-%E0%B8%AD%E0%B8%B1%E0%B8%A5%E0%B8%9F%E0%B9%88%E0%B8%B2%E0%B8%AD%E0%B8%B2%E0%B8%A3%E0%B9%8C%E0%B8%9A%E0%B8%B9%E0%B8%95%E0%B8%B4%E0%B8%99-%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7%E0%B9%83%E0%B8%AA%E0%B8%AD%E0%B8%A2%E0%B9%88%E0%B8%B2%E0%B8%87%E0%B8%9B%E0%B8%A5%E0%B8%AD%E0%B8%94%E0%B8%A0%E0%B8%B1%E0%B8%A2.html:jgbzojaw]Alpha Arbutin[/url:jgbzojaw] (Switzerland)
[url=http://www.myskinrecipes.com/shop/%E0%B8%A1%E0%B8%AD%E0%B8%A2%E0%B8%8B%E0%B9%8C%E0%B9%80%E0%B8%88%E0%B8%AD%E0%B8%A3%E0%B9%8C/75-allantoin-%E0%B8%AD%E0%B8%B2%E0%B8%A5%E0%B8%B1%E0%B8%99%E0%B9%82%E0%B8%97%E0%B8%AD%E0%B8%B4%E0%B8%99-%E0%B8%A5%E0%B8%94%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B8%B0%E0%B8%84%E0%B8%B2%E0%B8%A2%E0%B9%80%E0%B8%84%E0%B8%B7%E0%B8%AD%E0%B8%AD%E0%B8%87-%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%89%E0%B8%B2%E0%B8%99%E0%B8%81%E0%B8%B2%E0%B8%A3%E0%B9%81%E0%B8%9E%E0%B9%89-%E0%B8%AA%E0%B8%B3%E0%B8%AB%E0%B8%A3%E0%B8%B1%E0%B8%9A%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B9%81%E0%B8%9E%E0%B9%89%E0%B8%87%E0%B9%88%E0%B8%B2%E0%B8%A2.html:jgbzojaw]Allantoin[/url:jgbzojaw]
[url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%89%E0%B8%B2%E0%B8%99%E0%B8%A3%E0%B8%B4%E0%B9%89%E0%B8%A7%E0%B8%A3%E0%B8%AD%E0%B8%A2/74-vitamin-b3-niacinamide-%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%9A%E0%B8%B53.html:jgbzojaw]Safe-B3/url:jgbzojaw([url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%89%E0%B8%B2%E0%B8%99%E0%B8%A3%E0%B8%B4%E0%B9%89%E0%B8%A7%E0%B8%A3%E0%B8%AD%E0%B8%A2/74-vitamin-b3-niacinamide-%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%9A%E0%B8%B53.html:jgbzojaw]Vitamin B3, Niacinamide[/url:jgbzojaw])

For body lotion:

Bhaesaj lotion
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/147-%E0%B8%81%E0%B8%A3%E0%B8%94%E0%B9%82%E0%B8%88%E0%B8%88%E0%B8%B4%E0%B8%81-kojic-acid-dipalmitate.html:jgbzojaw]Kojic Acid Dipalmitate[/url:jgbzojaw]
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7/134-vitamin-c-l-ascorbic-acid-%E0%B8%9C%E0%B8%87%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%8B%E0%B8%B5.html:jgbzojaw]Vitamin C (L-ascorbic acid)/url:jgbzojaw
Mild Preserved Eco(TM)(Preservative-Free)
[url=http://www.myskinrecipes.com/shop/whitening-%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B9%83%E0%B8%AB%E0%B9%89%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%8ข%E0%B8%B2%E0%B8%A7/68-alpha-arbutin-%E0%B8%AD%E0%B8%B1%E0%B8%A5%E0%B8%9F%E0%B9%88%E0%B8%B2%E0%B8%AD%E0%B8%B2%E0%B8%A3%E0%B9%8C%E0%B8%9A%E0%B8%B9%E0%B8%95%E0%B8%B4%E0%B8%99-%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B8%82%E0%B8%B2%E0%B8%A7%E0%B9%83%E0%B8%AA%E0%B8%AD%E0%B8%A2%E0%B9%88%E0%B8%B2%E0%B8%87%E0%B9%8ป%E0%B8%A5%E0%B8%AD%E0%B8%94%E0%B8%A0%E0%B8%B1%E0%B8%A2.html:jgbzojaw]Alpha Arbutin[/url:jgbzojaw] (Switzerland)
[url=http://www.myskinrecipes.com/shop/%E0%B8%A1%E0%B8%AD%E0%B8%A2%E0%B8%8B%E0%B9%8C%E0%B9%80%E0%B8%88%E0%B8%AD%E0%B8%A3%E0%B9%8์/75-allantoin-%E0%B8%AD%E0%B8%B2%E0%B8%A5%E0%B8%B1%E0%B8%99%E0%B9%82%E0%B8%97%E0%B8%AD%E0%B8%B4%E0%B8%99-%E0%B8%A5%E0%B8%94%E0%B8%8ก%E0%B8%B2%E0%B8%A3%E0%B8%A3%E0%B8%B0%E0%B8%84%E0%B8%B2%E0%B8%A2%E0%B9%80%E0%B8%8ค%E0%B8%B7%E0%B9%88%E0%B8%AD%E0%B8%87-%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%8้%E0%B8%B2%E0%B8%99%E0%B8%8ก%E0%B8%B2%E0%B8%A3%E0%B9%81%E0%B8%9E%E0%B9%8้-%E0%B8%AA%E0%B8%B3%E0%B8%AB%E0%B8%A3%E0%B8%B1%E0%B8%9A%E0%B8%9C%E0%B8%B4%E0%B8%A7%E0%B9%81%E0%B8%9E%E0%B9%8้%E0%B8%8ง%E0%B9%88%E0%B8%B2%E0%B8%A2.html:jgbzojaw]Allantoin[/url:jgbzojaw]
[url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%8้%E0%B8%B2%E0%B8%99%E0%B8%A3%E0%B8%B4%E0%B9%8้%E0%B8%A7%E0%B8%A3%E0%B8%AD%E0%B8%A2/74-vitamin-b3-niacinamide-%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%9A%E0%B8%B53.html:jgbzojaw]Safe-B3/url:jgbzojaw([url=http://www.myskinrecipes.com/shop/%E0%B8%95%E0%B9%88%E0%B8%AD%E0%B8%95%E0%B9%8้%E0%B8%B2%E0%B8%99%E0%B8%A3%E0%B8%B4%E0%B9%8้%E0%B8%A7%E0%B8%A3%E0%B8%AD%E0%B8%A2/74-vitamin-b3-niacinamide-%E0%B8%A7%E0%B8%B4%E0%B8%95%E0%B8%B2%E0%B8%A1%E0%B8%B4%E0%B8%99%E0%B8%9A%E0%B8%B53.html:jgbzojaw]Vitamin B3, Niacinamide[/url:jgbzojaw])

I mixed a little bit of each ingredient into the base products. After 6 days, the face cream started changing from white to black and separated with a yellow liquid. The body lotion became liquid, likely because Bhaesaj lotion has high water and oil content. I would like to know if this is dangerous and ask for advice. All ingredients were purchased from this website.

MySkinRecipes Expert · Accepted Answer

Understanding Your Homemade Cosmetic Mixtures

You've observed significant changes in your face cream and body lotion mixtures after adding several active ingredients. The cream turning dark (from white to black) and separating with yellow liquid, and the lotion becoming liquid, are clear signs of instability in the formulations.

Here's a breakdown of why this likely occurred and the potential risks:

Reasons for Instability and Discoloration

Ingredient Incompatibility: Cosmetic formulations are complex systems where ingredients need to be compatible in terms of pH, solubility, and chemical reactivity. Mixing active ingredients like L-ascorbic acid, Kojic Acid Dipalmitate, Alpha Arbutin, Allantoin, and Niacinamide into existing finished products (like Pond's cream and Bhaesaj lotion) can disrupt their carefully balanced formulations.
L-Ascorbic Acid Oxidation: L-ascorbic acid (Vitamin C) is highly unstable, especially when dissolved in water and exposed to air or light. It easily oxidizes, which typically causes it to turn yellow, brown, or even black. This oxidation means the Vitamin C is degrading and losing its effectiveness. The yellow liquid you observed could be a sign of this degradation.
pH Issues: Different active ingredients require specific pH ranges for stability and efficacy. L-ascorbic acid needs a low pH (around 2.0-4.0), while Alpha Arbutin is stable between pH 3.5-6.5, and Niacinamide and Allantoin are stable in slightly higher ranges (pH 3-8). Mixing these into a base with an unknown pH can cause ingredients to break down or react negatively.
Emulsion Breakdown: Creams and lotions are emulsions, meaning oil and water phases are held together by emulsifiers. Adding powders or other substances can destabilize this emulsion, causing it to separate into its constituent parts (like the liquid and solid phases you observed).
Preservative System Compromise: Adding ingredients to a finished product can dilute or interfere with the original preservative system, even if you added an additional preservative like Mild Preserved Eco™. This can allow for microbial growth (bacteria, mold), which can further contribute to discoloration, odor, and potential skin irritation.

Is it Dangerous?

Yes, using a cosmetic product that has undergone such significant changes in color, texture, and separation is generally not recommended and can be unsafe.

Loss of Efficacy: The active ingredients have likely degraded and may no longer provide the intended benefits.
Potential Irritation or Allergic Reactions: The degradation products of unstable ingredients, or the ingredients themselves in an improper environment, can cause skin irritation, redness, itching, or allergic reactions.
Microbial Contamination: The breakdown of the formula and preservative system increases the risk of harmful bacteria or fungi growing in the product, which can lead to skin infections or other adverse reactions.

Recommendation

It is strongly advised to discard the mixtures you created. Cosmetic formulation requires specific knowledge of ingredient compatibility, stability, pH control, and preservation techniques. Simply mixing raw ingredients into existing products is unpredictable and often leads to unstable and potentially harmful results.

If you wish to use these active ingredients, consider:

Purchasing commercially formulated products from reputable sources that contain these ingredients. These products are developed and tested for safety and stability.
Following tested and validated cosmetic recipes from experienced formulators if you are interested in DIY, ensuring you understand the process, required equipment, and safety protocols.

We have information available on the individual ingredients you used, such as Kojic Acid Dipalmitate, Vitamin C (L-ascorbic acid), Mild Preserved Eco, Alpha Arbutin, Allantoin, and Safe-B3 (Vitamin B3, Niacinamide).