Moderate Cosmetic Ingredient

Methoxy PEG-100

INCI: METHOXY PEG-100

CAS Number
9004-74-4 (polyethylene glycol monomethyl ether series). "100" = ~100 EO units, avg. MW ~4,500 g/mol.
Function
Humectant, viscosity controlling, consistency enhancer. At this molecular weight, it is a solid waxy material.
Safety Rating
MODERATE

Regulatory Status

🇪🇺 EU Status permitted
🇺🇸 US Status permitted
US Notes Allowed. CIR has assessed PEGs and their derivatives as safe for cosmetic use.

For full compliance data across 55 jurisdictions, use the Substance Compliance tool.

Safety Data

Margin of Safety (MoS)
not established
Dermal Absorption
low
Sensitization
low

Calculate MoS for your specific formulation with the MoS Calculator.

Expert Verdict

Standard PEG profile - 1,4-dioxane and ethylene oxide residual traces as process impurities. With increasing molecular weight, skin penetration decreases significantly. Hygroscopicity decreases with higher MW.. Solid waxy substance at room temperature; used in water-free and water-rinse-off bases; when mixed with liquid PEGs, produces creamy consistencies.

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Concern Level: Moderate

Regulatory Flags

peg-ingredient

Frequently Asked Questions

Is Methoxy PEG-100 safe in cosmetics?

Standard PEG profile - 1,4-dioxane and ethylene oxide residual traces as process impurities. With increasing molecular weight, skin penetration decreases significantly. Hygroscopicity decreases with higher MW.. Solid waxy substance at room temperature; used in water-free and water-rinse-off bases; when mixed with liquid PEGs, produces creamy consistencies. The EU classifies Methoxy PEG-100 as "permitted". Safety rating: MODERATE.

Is Methoxy PEG-100 allowed in the EU?

Methoxy PEG-100 EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.

What does Methoxy PEG-100 do in cosmetics?

Methoxy PEG-100 functions as: Humectant, viscosity controlling, consistency enhancer. At this molecular weight, it is a solid waxy material.. It is classified as a cosmetic ingredient in our database. CAS number: 9004-74-4 (polyethylene glycol monomethyl ether series). "100" = ~100 EO units, avg. MW ~4,500 g/mol..

What is the Margin of Safety for Methoxy PEG-100?

not established The Margin of Safety (MoS) is calculated using SCCS methodology. A MoS above 100 is generally considered safe. Use the MoS Calculator tool to calculate MoS for your specific formulation and product category.

Compliance Tools

Check Methoxy PEG-100 compliance across multiple jurisdictions:

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Ingredient Decoder
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82 Allergen Checker
Check for EU declarable fragrance allergens
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Substance Compliance
Check compliance across 55 jurisdictions
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MoS Calculator
Calculate Margin of Safety using SCCS methodology
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Heavy Metal Limits
Compare limits across jurisdictions

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