Overview
SIST ISO 21322:2020 - Cosmetics - Microbiology - Testing of impregnated or coated wipes and masks provides guidance for the microbiological enumeration and detection of microorganisms in cosmetic products where the formulation is impregnated or coated onto a substrate (for example, wipes and masks). The standard addresses sampling and recovery challenges unique to these product forms and describes principles that can be adapted to similar products (cushions, impregnated sponges, applicators such as brushes, puffs or sponges).
Keywords: SIST ISO 21322:2020, cosmetics microbiology, impregnated wipes masks, bioburden testing.
Key topics and technical requirements
- Scope and applicability: Guidance for products where the cosmetic is not directly accessible and sampling may be difficult. Principles are adaptable to related product types.
- Selection of test sample: Use the entire unit where practical (minimum weight guidance) or a defined Unit Item Portion (UIP) that is microbiologically representative. Record test sample weight.
- Selection of method: Choose a testing approach based on product size, packaging, and expected bioburden to ensure representative results.
- Recovery of microorganisms: Procedures and preliminary treatments to release microbes from substrates, with verification that recovery methods do not affect viability.
- Enumeration methods: Enumeration of aerobic mesophilic microorganisms (bacteria, yeasts, moulds) using plate count methods (pour or spread) or membrane filtration, depending on sample volume and expected load.
- Detection of specified microorganisms: Use enrichment-based detection for pathogens or indicator organisms when required.
- Diluents, neutralizers and culture media: Selection and validation to ensure neutralization of antimicrobial components and reliable culture recovery.
- Suitability and validation: Perform suitability tests (Clause 11, Annex C) to verify method efficiency and neutralizer effectiveness.
- Documentation: Test report requirements and expression/interpretation of results (Annex B).
Practical applications and users
SIST ISO 21322:2020 is intended for:
- Cosmetic manufacturers performing in-house microbiological quality control for impregnated or coated products.
- Contract and third‑party microbiology testing laboratories handling wipes, sheet masks, and similar forms.
- R&D teams developing product formats where microbial recovery and neutralization are challenges.
- Regulatory bodies and auditors assessing microbiological testing procedures and compliance.
Benefits include improved consistency in bioburden estimation, validated recovery approaches, and clearer criteria for detection of specified microorganisms in non‑liquid cosmetic formats.
Related standards
SIST ISO 21322:2020 references and aligns with other cosmetics microbiology standards, including:
Adopting SIST ISO 21322:2020 helps organizations implement reliable, standardized testing for impregnated/coated cosmetic products and supports regulatory and quality assurance activities.