Bioscience Labs

Methods | PCPC


PCPC (formely referred to as Costmetic, Toiletry and Fragrance Association or CTFA):

The Personal Care Products Council provides guidance for preservative efficacy testing in Sections 20, 21, 22 & 23 of their Microbiological Guidelines. Products are categorized as such:

  • M-3 – Water miscible personal care products
  • M-4 – Eye area personal care products
  • M-5 – Nonwoven substrate personal care products
  • M-6 – Atypical personal care products

The PCPC guidance is the most stringent preservative efficacy currently available and the testing can be conducted in either mixed or pure suspensions. Inocula consisting of only pure microbial cultures will yield specific data on each test microorganism. When using mixed inocula, closely related types of microorganisms, such as Gram-positive bacteria, Gram-negative bacteria and yeasts and molds should be pooled separately. The PCPC recommends challenging products against between five and seven microorganisms and lists possible optional microorganisms that can be added to the assay. Although sampling is indicated at several time points during 28 days, it also allows for the option of a re-challenge of the product at 56 days.

Personal Care Products Council (PCPC)

Preservation Testing of Water-Miscible Products Challenge testing a formula with known microorganisms to verify that if the products become contaminated, the preservative system is sufficient to inhibit the growth of the microorganisms and spoilage. The CTFA…
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