FDA recommends that the labeling of a cosmetic product that contains an AHA as an ingredient and that is topically applied to the skin or mucous membrane, such as the lips, bear a statement that conveys the following information:

Based on industry-sponsored studies, the Cosmetic Ingredient Review (CIR) Expert Panel — the industry's self-regulatory body for reviewing the safety of cosmetic ingredients concluded that products containing the AHAs glycolic are safe for use by consumers only if:

The final product has a pH of 3.5 or greater.

The final product is formulated in such a way that it protects the skin from increased sun sensitivity or its package directions tell consumers to use daily protection from the sun.

The challenge of a subjective response from customers related to the "feel" and "sensitivity" associated with using any product, is that it is difficult to narrow this down to one variable that may be altering their perception or altering its effect.

Variables that may influence this include:

1. The pH of the skin can change slightly or dramatically over the course of a week, month or year.

2. The amount of oil on the skin can affect acid penetration and absorption.

3. The use of other products on the skin, including make up, soap and moisturizers can alter absorption.

3. The amount and frequency of use can alter perception of activity.

3. The health of the customer and any medical conditions they may have, can alter absorption and perception.

4. Drugs and medications can interact with skin applications and alter their effect.

5. Slight variations in natural formulations (<1%), as well as in the amount applied on the skin may affect the "feel" the customer reports.

6. Repeated and continuous use can create a desensitization to the "feel" of the product on the skin.

(This is exactly why professional peels can be done in increasing increments, because the patient builds up a sensation tolerance.)

All these variables may affect the client's subjective perception of the products performance.
This perception information is not an accurate means of checking effectiveness of the product, nor is it reliable.

We can only guarantee that the product we ship out to you will have a pH that is 0.2 - 0.5, which is per the formulation standards set for this product and that the product has been tested and meets all QA criteria for the formulation.

Glycolic Acid does not create or become a new or different molecule over time. So, it does not change into something else as it ages. It can only degrade over a long period of time (several years), losing its effectiveness when exposed to atmospheric changes. (Temps greater than 140 F and lower then 68 F)

Glycolic acid is stable and will not degrade when stored in an unopened container in ambient temps up to 140 F.

Glycolic acid may precipitate when stored below 68 F. However, the material will fall back into solution when heated to 104 F with agitation. This will not affect performance or pH.

Glycolic Acid may create a dimer (glycolide) when heated/stored above 140 F. If the dimer is created, the material will lose acidity affecting the pH.

Although all products are required to list a shelf life, Glycolic acid does not really have a defined shelf life and can maintain its pH indefinitely if stored properly.

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