Are there alternatives to microplastic rheology modifiers such as carbomer in cosmetics?

Why are polymers neutralized during formulation defined as microplastic?

Synthetic solid polymers can be excluded from the microplastic definition via the solubility criterion by the supplier but it has to fulfill certain requirements. According to Appendix 16 of the (EU) microplastic restriction,the test shall be performed at pH 7 on a test material comparable in terms of composition, form, size and surface area to the commercialized form.

For polymers that must be neutralized during formulation, such as carbomer, at pH7 (pH of the test), they are chemically modified in a salted form (neutralized) making them different from their original state (as commercialized). Hence, the test is not applicable and polymers that must be neutralized during formulation are microplastics, if they are not biodegradable according to Appendix 15 and with carbon atoms. Thus, carbomer, one of the most widely used rheology modifiers in cosmetics - over 1500 new skin care products with carbomer are introduced to the European market per year - is defined as a microplastic according to the European restriction. As a result cosmetics manufacturers using a carbomer will have to navigate complex steps to ensure regulatory compliance.

What are the constraints associated with the use of microplastics in a cosmetic product to avoid its market ban?

• The cosmetic manufacturer must demonstrate with sufficient scientific rational/evidence that the microplastic is permanently modified.
• If there is not enough proof, question the use of the microplastic ingredient in the cosmetic product and comply with obligations. To learn more about these obligations, read this article.

Which alternatives to microplastics are available for use in cosmetics?

Look for soluble synthetic solid polymers that can:

• improve the ease of use with ready to use & time-saving rheology modifiers. Whereas polymers that need neutralization such as carbomer need to avoid high shearing (rotor/stator) during dispersion in water and can only be introduced into the water phase, Seppic’s rheology modifiers are pre-neutralized and don't need neutralization during formulation. They can also be added into the water phase, into the oily phase or during emulsification.
• improve the stability of the formula with performant rheology modifiers. Whereas carbomer is not compatible with cosmetic products containing DHA or not thickening at a high acidic pH such as rinse-off intimate care or products containing certain hero ingredients or preservatives, Seppic’s non microplastic solid rheology modifiers such as Sepinov™ EMT 10, Sepinov™ WEO and Sepimax Zen™ achieve a good performance. Sepinov™ WEO is the fresh and satiny powder polymer specifically recommended for EO free concepts. When developing cold processed emulsions without an emulsifier and when stabilizing classic emulsions that contain a high percentage of oils, they present a better performance in comparison with carbomer, thanks to their excellent oil stabilizing property. Moreover, when formulating an exfoliating product there is to maintain in suspension a percentage of particles while presenting a resistance to electrolytes. In this case carbomer can be replaced by Sepimax Zen™ even for formulas with a very low viscosity.

Look for natural rheology modifiers such as Seppic’s natural rheology modifiers of the Solagum™ range that are powerful biodegradable natural origin polymers for all applications. They are multifunctional and present synergistic effects when combined with one to another.

All Seppic’s rheology modifiers are non microplastic according to the European regulation while achieving high performance. Formulating with Seppic’s non microplastic rheology modifiers is formulating with ease of mind. It means:

• Non microplastic status is proven because Seppic has carried out the solubility test according to OECD 120 in GLP conditions (method required by ECHA, the European Chemicals Agency, in Appendix 16) and biodegradability tests in GLP conditions or in laboratories accredited to ISO 17025 (according to methods required by ECHA, listed in Appendix 15) .
• In-depth expertise because Seppic provides statements with test references and detailed results. 
• Reactivity because Seppic can share to competent authorities upon their request a full folder demonstrating that its rheology modifiers are not microplastic.

No constraints nor obligations linked to the microplastic restriction.