What Is It?
Zinc oxide (ZnO) is powdered, oxidized zinc derived from the naturally occurring mineral zincite. It is used in a wide range of cosmetics and personal care products including makeup, baby lotions, bath soaps and foot powders. It is also well-recognized as an important skin protectant and sunscreen ingredient to protect the skin from the sun’s harmful ultraviolet (UV) radiation. It is widely used in other consumer products as an additive in rubbers, plastics, ceramics, lubricants, paints, ointments, adhesives, sealants, pigments, foods and first-aid tapes, providing white color, preventing discoloration of plastics and paints, and acting as a fungicide and bactericide.
Why is it used in cosmetics and personal care products?
ZnO is a white powder commonly used in cosmetics as a bulking agent and a colorant. In the U.S., it is also used in over-the-counter (OTC) drug products, such as diaper rash creams as a skin protectant and in sunscreen products as a broad-spectrum UV filter.
In sunscreens, ZnO acts as a physical blocker to the sun’s UV rays. It is the broadest spectrum UVA and UVB reflector approved by the U.S Food and Drug Administration (FDA) for use as a sunscreen. Exposing unprotected skin to UV light can result in sunburn (primarily from UVB rays) and promote premature aging of the skin, as well as skin cancer (primarily from UVA rays). Although ZnO generally imposes a white color to products, microfine or nanoscale ZnO (or when made into a very fine powder) does not impose a white cast when applied to the skin.
ZnO is also approved as an active sunscreen ingredient in Canada, Australia, the European Union and Japan.
Safety Information:
United States
FDA
The FDA lists ZnO as generally recognized as safe (GRAS) as a nutrient. It is approved as an indirect food additive as a colorant of some polymers in contact with food. ZnO is an approved colorant for use in color cosmetics products, including those applied to the lips and eye area, and as a colorant in drug products. FDA approves colors only after extensive review of all safety data. When used as a colorant in cosmetics or other FDA-regulated products, zinc oxide must comply with the identity, specifications, uses, restrictions and labeling requirements stated in the regulations [21 CFR 73].
Additionally, the FDA has approved the use of ZnO in over-the-counter (OTC) skin protectants and anorectal skin protectant drug products.
Use in Sunscreens
Sunscreens are regulated by the FDA as non-prescription, OTC drugs through a monograph system, which establishes various requirements for the product to be sold in the U.S. A monograph specifies the types of ingredients, dosage forms, testing methods, labeling requirements, and other related details for a product category, such as sunscreens. If a manufacturer follows the sunscreen monograph, its sunscreen products do not require separate FDA pre-approval before they can be sold in the U.S.
While the FDA proposed an Administrative Order on Sept. 27, 2021, that would amend conditions under which nonprescription sunscreen drug products would be determined to be generally recognized as safe and effective (GRASE), the GRASE status for ZnO is not expected to change once the proposed Administrative Order is finalized.
CIR
The Expert Panel for Cosmetic Ingredient Safety (formerly the Cosmetic Ingredient Review Expert Panel) has deferred evaluation of ZnO because its safety has been assessed by the FDA. This deferral of review is according to the provisions of the CIR Procedures.
European Union (EU)
The Cosmetics Directive of the European Union approved ZnO as a colorant (see Annex IV ). When used in cosmetics products, it is labelled CI 77947. In its Sept. 18, 2012, opinion (revised Sept. 23, 2014), the EU’s Scientific Committee on Consumer Safety (SCCS) concluded ZnO is safe when used as a colorant in cosmetics for dermal application in its uncoated, non-nano particle form (see separate webpage on nanotechnology). However, in light of subsequent SCCS concerns of potential lung inflammation induced by ZnO particles after inhalation, the European Commission amended Annex IV of the Cosmetics Regulation in August 2017 to stipulate that ZnO as a colorant in its uncoated, non-nanoparticle form in cosmetics products should be restricted to applications that will not lead to exposure of the end-user’s lungs.
ZnO is also allowed as a UV filter in the EU at concentrations up to 25%. The SCCS has thoroughly reviewed the safety of nanoscale (1-100 nm) ZnO used in sunscreens and concluded it does not pose a risk of adverse effects. In 2016, the European Commission amended Annex VI of the EU Cosmetics Regulation to also include nano-sized ZnO as a permitted UV filter in ready-to-use cosmetics products. Both nano and non-nano forms are restricted to applications that will not lead to exposure of the end-user’s lungs.
Resources:
EU SCCS Opinion on Nano ZnO 2012
EU SCCS Opinion on Nano ZnO 2014
American Academy of Dermatology – “Is Sunscreen Safe?”
Skin Cancer Foundation – “Skin Cancer Issues and Research”
Centers for Disease Control & Prevention (CDC) – “Sun Safety”