A baby-product label can identify a listed preservative or ethoxylated ingredient, but it cannot reveal the amount released, an unlisted impurity or a child's absorbed dose.[1] [2]
Formaldehyde release depends on the formula
DMDM hydantoin, quaternium-15, imidazolidinyl urea and related preservatives can release formaldehyde. Release varies with time, temperature, pH and product matrix, so an ingredient name does not predict a concentration.[1]
1,4-dioxane is a possible byproduct
PEG, laureth, oxynol and similar names can indicate ethoxylation, a process that can generate 1,4-dioxane. They do not prove that a finished product is contaminated. FDA monitoring shows levels fell greatly from historical surveys.[2]
Fragrance disclosure is limited
US labels can list fragrance collectively, and unscented may include masking fragrance. Choose fragrance-free when avoiding fragrance is the goal.[3] [4]
Marketing words are not exposure measurements
Natural, clean and gentle do not supply chemical concentration, absorption or health-outcome data. Natural fragrance can also cause contact allergy.[5]
A practical label check
No label can prove zero risk.
- Choose a product that meets the child's skin and cleansing needs.
- Use fragrance-free if scent is unnecessary or irritating.
- If a child has diagnosed formaldehyde allergy, follow a clinician's avoidance advice.[6]
- Stop using a product that causes a reaction and seek clinical advice.
Sources for this article
Each source below states the claim it supports and the limits of that evidence.
Lv C, Hou J, Xie W, Cheng H. 2015. Investigation on Formaldehyde Release from Preservatives in Cosmetics. International Journal of Cosmetic Science. DOI: 10.1111/ics.12212. PMID: 25704726.
Supports: Formaldehyde release from tested preservatives changed with preservative, time, temperature, pH and formulation.
Evidence class: Analytical chemistry study
US Food and Drug Administration. n.d.. Title not stated in the supplied verified corpus. US Food and Drug Administration.
Supports: Ethoxylation can create 1,4-dioxane, but a related ingredient name does not prove contamination. FDA surveys show large declines from historical levels.
Evidence class: Federal monitoring and guidance
US Government Publishing Office. 2025. Designation of Ingredients. Code of Federal Regulations.
Supports: US rules permit fragrance ingredients to be declared collectively as fragrance. This permission does not mean every undisclosed ingredient is hazardous.
Evidence class: Federal regulation
US Food and Drug Administration. n.d.. Fragrances in Cosmetics. US Food and Drug Administration.
Supports: FDA explains that fragrance can represent multiple natural or synthetic ingredients and that unscented products may use masking fragrance.
Evidence class: Federal labeling guidance
Diepgen TL, Ofenloch R, Bruze M, et al.. 2015. Prevalence of Fragrance Contact Allergy in the General Population of Five European Countries. British Journal of Dermatology. DOI: 10.1111/bjd.14151. PMID: 26332456.
Supports: Clinically relevant fragrance allergy was estimated at 1.9% in a European general-population sample. Natural origin does not prevent allergenicity.
Evidence class: Human cross-sectional patch-testing study
Atwater AR, Petty AJ, Liu B, et al.. 2021. Contact Dermatitis Associated with Preservatives: Retrospective Analysis of North American Contact Dermatitis Group Data, 1994 through 2016. Journal of the American Academy of Dermatology. DOI: 10.1016/j.jaad.2020.07.059. PMID: 33579596.
Supports: Formaldehyde and several releasers produced positive reactions in referred patch-test patients. Referral-clinic rates are not general-population prevalence.
Evidence class: Human clinical patch-testing study