PCPC (CTFA) Test Methods

PCPC testing ( (formerly CTFA) – Determination of the Microbial Content of Cosmetic Products

The Personal Care Products Council (PCPC) outlines guidelines and recommendations for the testing and safety assessment of cosmetic and personal care products.

The Personal Care Products Council Microbiology Guidelines helps the cosmetic and personal care product manufacturers to employ quality assurance practices to ensure the microbiological safety of their products for consumers.

MIS offers following Microbial enumeration examination and Preservative efficacy test as per PCPC guidelines –

• PCPC M -1 – Detection of the Microbial Content of Cosmetic Products
• PCPC M – 2 – Method for detection of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa in cosmetic products
• PCPC M – 3 – Preservation testing of Water-Miscible Personal Care Products
• PCPC M – 4 – Preservation Testing of Eye Area Cosmetics
• PCPC M – 5 – Preservation Testing of Nonwoven Substrate Personal Care Products
• PCPC M – 6 – A Method for Preservation Testing of Atypical Personal Care Products
• PCPC M – 7 – A Rapid Method for Preservation Testing of Water-Miscible Personal Care Products

PCPC M – 1 : Determination of the Microbial Content of Cosmetic Products

PCPC M -1 test helps to determine microbial content, including bacteria, fungi, yeast, and mold present in given cosmetic and personal care products. PCPC M -1 testing is employed for raw materials, bulk products, in-process materials, and finished products.

PCPC M – 1 test method

• For water-miscible products, 10mL or gms of the product sample is diluted into 90 mL of diluent to make the dilution ratio of 1:10.The product and diluent are mixed or vortexed until homogeneity is achieved. For water-immiscible products, 10 mL or gms of product sample is diluted into 10 mL of Polysorbate 80 and dispersed properly. The volume is made to 100 mL with diluent to make the dilution ratio of 1:10. Again, the product and diluent are mixed or vortexed until homogeneity is achieved.
• When the same agar is used for bacterial and fungal assays, 1 mL of the dilution is dispensed into each of three Petri dishes and 0.1 mL into three additional Petri dishes. 15 to 20 mL melted agar medium is added and kept at 44°-48°C, and then plates are rotated sufficiently to disperse the product. The agar is allowed to solidify, and the plates are inverted. One plate of each dilution is incubated as follows:
• For the bacterial assay, plates are incubated at 30°-35°C for a minimum of 2 days. For the fungal assay, plates are incubated at 20°-25°C for a minimum of 5 days. Remaining plates (control) are kept in the refrigerator to prevent the growth.
• The number of colony forming units (CFU) per mL or g is the colony count multiplied by the appropriate dilution factor (10 or 100). If the number of colonies appears to exceed 250 CFU, the plate may be sectioned for an estimated count. For plates where colonies are too numerous and unable to be clearly distinguished, the plate may be marked as “Too Numerous to Count” (TNTC).

Morphologically suspect colonies can be further identified by the methods described in
PCPC M-2 Examination for and Identification of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans.

PCPC M – 2 : Examination for Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa

PCPC M-2 provides general guidelines for the identification of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans which have been isolated in PCPC M-1 testing.

The identification of other microorganisms including Burkholderia and Enterobacter species can come within the scope of PCPC M – 2. Presence of listed objectionable microorganisms in cosmetic and personal care products not only impact product integrity but also found to have harmful impact on customer health.

PCPC M – 2 test method

• Colonies appearing after 18-24 hours of incubation are subjected to gram staining and examined to identify gram positive and gram negative and cellular morphology characterstics of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa.
• For identification of Staphylococcus aureus – Vogel-Johnson Agar (VJA), Mannitol Salt Agar (MSA) or Baird Parker Agar (BPA) is used as a selective/ differential media.
• For identification of Escherichia coli – Eosin Methylene Blue (EMB) or MacConkey Agar Plates (Mac) is used as a selective/ differential media.
• Pseudomonas aeruginosa – Cetrimide or Pseudomonas Isolation Agar (PIA) plates is used as a selective/ differential media.
• Candida albicans – BiGGY agar, Chromogenic agar or Corn meal agar with 1% polysorbate 80

Other biochemical tests may be conducted as required for identification of objectionable microorganisms.

PCPC M-3 : A Method for Preservation Efficacy Testing of Water Miscible Personal Care Products

PCPC M-3 test for water-miscible personal care products is a critical step in product development and quality assurance. PCPC M-3 test ensures that tested products remain free from harmful microorganisms and maintain their desired characteristics throughout their shelf life.

Preliminary tests

Preservative Neutralization – Neutralization of the antimicrobial properties of the formulation needs to be carried out in the plate count diluent and/or the recovery growth agar to avoid false results of preservative efficacy test.

Microbial Content Test – It also needs to be performed prior to preservative efficacy test.

PCPC M-3 test method

• Following Standard inoculum of challenge bacteria is used for testing
  • 1. 1×106 Colony-Forming Units (CFU) of bacteria per gram of product
    2. 1×105 CFU of yeast per gram of product
    3. 1×05 CFU of mold spores per gram of product
  • Challenged formulations are sampled to determine viable microorganisms at selected time intervals after inoculations. Quantitative pour plate method, quantitative spread plate method, and quantitative spiral plate method is used for sampling of products.
  • Product sampling should be done at specific intervals i.e weekly to 28 days to ensure consistent and comparable test results across various product formulations or samples.

  PCPC M-4 : Testing for Preservation Efficacy Testing for Eye Area Personal Care Products

  PCPC M-4 method is designed to ensure the safety and efficacy of cosmetic and skincare products intended for use around the eyes.

  PCPC M-4 test method

  • Following Standard inoculum of challenge bacteria is used for testing –
    
    • 1. 1×106 Colony-Forming Units (CFU) of bacteria per gram of product
      2. 1×105 CFU of yeast per gram of product
      3. 1×05 CFU of mold spores per gram of product
    • Challenged (inoculated) formulations are sampled for viable microorganisms at selected time intervals i.e. 0 hour and 1, 3, 7, 14, 21 and 28 days.

    PCPC M-5 : Method for Preservation Testing of Nonwoven Substrate Personal Care Products

    PCPC M-5 method has been devised to check the preservative efficacy of nonwoven substrate personal care products including wipes, masks, or towelette and various hygiene items

    PCPC M-5 Test Method

    • Sample of wipes/ towelette is aseptically opened and directly inoculated and resealed.
    • Product sampling should be done at specific intervals i.e weekly to 28 days to ensure consistent and comparable test results across various product formulations or samples.
    • Inoculated product samples are transferred into preservative neutralizing diluent. Care must be taken to sample the areas of the product that have been inoculated.
    • Recovered solution is serially diluted, and then plated and incubated for a specific period of time to enumerate viable cells.

    PCPC M-6 : Method for Preservation Testing of Atypical Personal Care Products

    PCPC M-6 method describes test procedure and acceptance criteria to determine the preservative efficacy of atypical personal care products having low water content/ not miscible with water. Product type may include oils, powders, or other formulations.

    Preliminary tests

    Preservative Neutralization – Neutralization of the antimicrobial properties of the formulation needs to be carried out in the plate count diluent and/or the recovery growth agar to avoid false results of preservative efficacy test.

    Microbial Content Test – Test is performed prior to preservative efficacy test.

    PCPC M-6 Test Method

    • 20 mL or 20 grams of the cosmetic sample is challenged with 0.1% to 1.0% of test inoculum.
    • The frequency of sampling is done at specific intervals to get comparable and reproducible test results.
    • Sampling intervals should be based on microbial contamination risk as demonstrated by product water activities and other microbiological related attributes –
      
    • Water in oil and/or silicone emulsions
      • Sampling intervals, including 7, 14, 28 days
      • Sampling intervals, including 7, 14, 28 days
      • Sampling intervals, including 2,7,14,28 days.
      • Sampling intervals, including 2,7,14,28 days
      • Sampling intervals, including 2,7,14,28 days

      PCPC M-7 : Screening Method for Preservation Testing of Water- Miscible Personal Care Products

      PCPC M-7 serves as a preliminary test during cosmetic product development to distinguish between preservative systems that could provide adequate protection to the product and those lacking sufficient antimicrobial properties.

      It is not intended to provide the conclusive information regarding the preservation adequacy of the final product formulation.

      PCPC M-7 method

      • Test product is challenged with viable microorganisms .
      • Challenged formulations are sampled at an interval of 1, 2 or 3 and 7 days to obtain reproducible results.

      Importance of PCPC testing

      Microbial contamination of cosmetic products is mainly attributed to their composition, poor manufacturing practices or storage. Using microbially contaminated cosmetic products can lead to health concerns, ranging from skin irritations to more serious infections. Hence, meticulous testing procedures are essential to identify and eliminate these risks.

      Personal Care Products Council (PCPC) has established a comprehensive framework that outlines appropriate sampling techniques and test methods for screening of pathogenic microorganisms. It also includes preservative efficacy evaluation to ensure preservatives are effective and capable of preventing contamination throughout a product’s shelf life. The PCPC’s guidelines help companies ensure that their products meet the highest standards of quality, further enhancing consumer trust.

      At MIS, we provide an extensive range of microbiology cosmetics testing services as per different industry standards like USP, ISO, and PCPC (formerly CFTA).

      Our comprehensive microbiology testing services encompass preservative efficacy testing and enumeration tests for both semi-finished and finished formulations. We employ state-of-the-art microbiological testing facilities equipped with cutting-edge technology to ensure precise and reliable results.

      MIS has a team of industry experts with extensive hands-on experience in establishing and operating testing protocols.