Ethoxydiglycol (EDG) is widely used in personal care and cosmetic products. Despite its utility, it has become the subject of regulatory debate, leading many to question if it has been banned. Its regulatory status is complex, marked not by universal prohibition but by strict, science-based concentration limits and usage restrictions in major markets. Understanding these limitations requires reviewing its chemical function and toxicological data.
What Ethoxydiglycol Is and How It Is Used
Ethoxydiglycol, chemically known as Diethylene Glycol Monoethyl Ether (DEGEE), is a clear, colorless, low-viscosity liquid belonging to the glycol ether family. It is a synthetic molecule created through the ethoxylation of ethanol. In cosmetic formulations, its primary role is that of an excellent solvent, helping to dissolve and suspend other ingredients that might not readily mix with water or other base components.
Beyond its solvent properties, EDG is highly valued as a penetration enhancer. This means it temporarily alters the skin’s barrier function, allowing active ingredients to absorb deeper and more effectively into the skin. This capability is particularly useful in products containing challenging-to-deliver molecules, such as Vitamin C or the self-tanning agent Dihydroxyacetone (DHA). The ingredient also acts as a humectant and is often used to reduce the viscosity of a product.
The Regulatory Status: Is It Truly Banned?
Ethoxydiglycol is not universally banned in the cosmetic industry, which is a common misconception stemming from the severity of restrictions. The substance is listed as a restricted ingredient in many key markets, meaning its use is permitted only up to certain concentration thresholds and in specific product types. The perception of a “ban” often arises because the limits are stringent enough to force reformulation.
The European Union’s Cosmetic Regulation (EC) No 1223/2009 lists EDG in Annex III, the official list of restricted substances. This regulatory approach signifies that the ingredient is considered safe when used within defined, conservative parameters. The regulations specifically ban its use in products intended for the eye area and oral hygiene, such as toothpaste, due to the higher risk of systemic exposure in these applications.
The Scientific Basis for Restriction
Restrictions on Ethoxydiglycol result directly from scientific safety assessments conducted by independent bodies, notably the Scientific Committee on Consumer Safety (SCCS) in the European Union. The SCCS determined that the primary concern relates to its potential for systemic exposure. This is due to the ingredient’s high dermal absorption rate, which is the very mechanism that makes it an effective penetration enhancer.
Rapid absorption through the skin increases the risk of systemic toxicity if EDG is used at high concentrations or in large volumes. Scientific investigations indicated a potential for kidney damage and minor developmental effects in high-dose animal studies, which prompted a precautionary approach from regulators.
The restrictions also aim to limit the absorption of impurities, particularly trace amounts of ethylene glycol, a known toxic substance present in poorly purified EDG. Regulations thus serve a dual purpose: limiting the amount of EDG entering the bloodstream and imposing strict purity criteria requiring extremely low ethylene glycol impurity levels.
Global Regulatory Differences and Usage Limits
The specific concentration limits for Ethoxydiglycol vary significantly between major regulatory jurisdictions. The European Union, following the SCCS opinions, has established some of the world’s strictest limits. For non-spray, leave-on cosmetic products, such as creams and serums, EDG is restricted to a maximum concentration of 2.6% in the finished product.
Higher concentrations are permitted for products where the exposure time is minimal or the product is quickly washed off. For instance, rinse-off products allow up to 10%, and oxidative hair dye formulations are limited to 7%.
In contrast, the United States takes a different approach, as the Food and Drug Administration (FDA) has not imposed federal restrictions on EDG. The Cosmetic Ingredient Review (CIR) Expert Panel has generally deemed the ingredient safe for use at current levels. These differing regulatory frameworks mean that a product acceptable in the US may be illegal for sale in the European Union unless it strictly adheres to the EU’s specific concentration limits.