Cosmetics are formulated for application to external surfaces of the body, including skin, hair, nails, and lips. From a formulation perspective, they are essentially applied coatings or surface treatments designed to temporarily modify, protect, cleanse, or alter personal appearance. The FDA definition (21 USC § 321(i)) includes articles intended to be applied to the human body for “cleansing, beautifying, promoting attractiveness, or altering the appearance,” as well as components of such articles, excluding soap.

From a physical-chemistry perspective, dispersions can be classified according to the size and physical state of the dispersed matter. Generally, dispersions can be divided into three main types: coarse dispersions (e.g., suspensions), colloidal dispersions, and molecular dispersions (homogeneous solutions). Note that many terms represent common cosmetic formulation-industry jargon despite similarities in the underlying physical and chemical principles.

Within these classifications, dispersion can broadly describe the various forms of cosmetic products in which ingredients are distributed throughout a formulation. From a practical formulation perspective, the objective is to obtain a controlled and sufficiently uniform distribution of the formulation components, regardless of their individual solubility or the mechanisms by which that distribution is achieved. Solutions are conventionally described as homogeneous systems in which one or more ingredients are dispersed at the molecular or ionic level within a continuous phase. Examples include aqueous toners, hydroalcoholic fragrances, some cleansers, and solutions of salts, acids, polymers, surfactants, or other soluble cosmetic ingredients. Heterogeneous mixtures contain distinguishable components or phases at a specified scale, yet those components must be sufficiently and uniformly distributed throughout the formulation to provide the intended composition and performance. Such systems may appear macroscopically homogeneous while remaining heterogeneous at smaller length scales. Industrial formulation jargon must therefore be correlated with scientific terminology to ensure clarity in communication.

In formulating cosmetic products, dispersion is the objective of distributing or embedding a substance within another material or continuous phase. Dispersions can be classified according to the size and physical state of the dispersed matter. Generally, dispersions can be divided into three main types: coarse dispersions (e.g., suspensions), colloidal dispersions, and molecular dispersions (homogeneous solutions). Interactions within dispersed systems may include electrostatic interactions, hydrogen bonding, hydrophobic interactions, physical or polymer-chain entanglement, and van der Waals forces. The dispersion process involves overcoming or modifying intermolecular and interfacial interactions sufficiently to distribute one material throughout another.

Risk-Based New Product Development and R&D

DJC approaches formulation from fundamental chemical and physical principles rather than relying solely on conventional industry formulation practices. Product development begins by defining the intended function, application conditions, user and environmental considerations, and required product performance. Whenever practical, formulations are developed using the minimum number of ingredients necessary to achieve the intended function, with consideration given to materials from natural or environmentally compatible sources. Natural-source materials may require isolation, purification, characterization, or other processing before incorporation into a formulation. Depending on the intended application, development may also include control of microbial contamination, product stability, skin compatibility, and performance under anticipated conditions of use.

DJC evaluates regulatory compliance, product safety, raw materials, and anticipated conditions of use before chemicals are purchased or experimental formulation work begins. Applicable requirements may include the Federal Food, Drug, and Cosmetic Act and MoCRA, TSCA, CPSIA, and other CPSC requirements, depending upon the composition, intended use, presentation, and distribution of the finished product.

DJC also applies a risk-based approach beyond minimum regulatory requirements when the intended application presents additional exposure concerns. Products used around the eyes or mouth, for example, may present additional risks associated with microbial contamination or inadvertent exposure. Microbial contamination is addressed under the adulteration provisions of the FD&C Act, including §601(a) and (c) [21 U.S.C. §361(a), (c)]. FDA has also specifically identified contaminated eye-area cosmetics as having caused serious infections.

· FD&C Act §601(a), (c) - adulterated cosmetics.

· 21 U.S.C. §361(a) — a cosmetic is adulterated if it contains a poisonous or deleterious substance that may make it injurious under labeled or customary conditions of use.

· 21 U.S.C. §361(c) — a cosmetic is adulterated if it is prepared, packed, or held under insanitary conditions whereby it may become contaminated with filth or rendered injurious to health.

For these applications, DJC may incorporate relevant microbiological and manufacturing controls derived from pharmaceutical cGMP requirements under 21 CFR Parts 210 and 211, even when those requirements are not legally applicable to the cosmetic product.

Raw-material selection begins with supplier qualification and review of available specifications, certificates of analysis, microbiological data, manufacturing controls, traceability, and lot-to-lot consistency. Consideration is given to materials of natural or biological origin because their chemical and microbiological characteristics may vary with genetics, geographic origin, environmental and growth conditions, harvesting, processing, storage, and purification. Where appropriate, specific constituents of a natural extract may be isolated and purified, since an extract may contain numerous dissolved or dispersed components that are unnecessary or undesirable for the intended application.

Regulatory Documentation and Safety Substantiation

Under the Modernization of Cosmetics Regulation Act of 2022 (MoCRA), the responsible person for a cosmetic product must ensure and maintain records supporting adequate substantiation of the product's safety under FD&C Act §608 [21 U.S.C. §364d]. Adequate substantiation may consist of tests or studies, research, analyses, or other evidence considered by appropriately qualified experts to be sufficient to support a reasonable certainty that the cosmetic product is safe. Safety applies to the finished cosmetic product and its ingredients under labeled, customary, or usual conditions of use, and relevant cumulative exposure may also be considered.

The documentation used to support safety substantiation may therefore include ingredient and raw-material specifications, supplier documentation, available toxicological and safety data, chemical composition, intended conditions of use and exposure, microbiological considerations, analytical and stability information, and additional testing or scientific analyses when necessary. FDA does not prescribe a specific set of tests for every cosmetic or ingredient; existing scientifically appropriate information may be used, supplemented by additional testing appropriate to the product and its intended use.

MoCRA also strengthened the regulatory significance of this documentation. Under FD&C Act §601(g) [21 U.S.C. §361(g)], a cosmetic product is considered adulterated if the product, including each ingredient, does not have adequate substantiation of safety as defined under §608(c). Accordingly, DJC incorporates safety substantiation and its supporting documentation into product development so that the scientific basis for ingredient selection, formulation, testing, intended use, and product safety is established and documented as the product is developed rather than assembled retrospectively.

Regulatory documentation also supports transfer of the developed product into controlled manufacturing and may include the approved formulation and specifications, raw-material and finished-product specifications, supplier qualification and Certificates of Analysis (CoAs), Safety Data Sheets (SDSs), SOPs, manufacturing instructions and batch records, testing and release criteria, stability and microbiological data, labeling and traceability records, and the supporting product dossier or technical file. These records are maintained as applicable under ISO 22716 cosmetic GMP, MoCRA and the FD&C Act, TSCA, CPSIA/CPSC requirements, and OSHA 29 CFR §1910.1200 for workplace hazardous-chemical communication.

Note: CPSC children's-product requirements generally apply to products designed or intended primarily for children 12 years of age or younger. DJC may nevertheless consider reasonably foreseeable child exposure when evaluating product safety, including the possibility that a child could access or use an adult cosmetic. Such considerations may also be incorporated into customer- or retailer-specific product safety requirements beyond minimum federal regulatory requirements.

Continuous Product Improvement

Continuous product improvement may involve modification of an existing formulation, ingredient, raw material, supplier, manufacturing process, specification, packaging, or other product characteristics. DJC manages modifications through documented change control, including review of the effect of the proposed change on product safety, quality, performance, regulatory compliance, safety substantiation, specifications, SOPs, manufacturing records, testing, labeling, and other controlled documentation. Under MoCRA, FD&C Act §607(c) [21 U.S.C. §364(c)], changes affecting information contained in a cosmetic product listing, including formulation ingredients, are incorporated into the required annual product-listing update.

Cosmetic Formulations