TAMC, TYMC, and absence test for personal care products, pharmaceuticals, cosmetics, and other products categorized as non-sterile. Blog post by Sneha Mistry

July 1, 2024

USP<61>

USP<61> refers to the United States Pharmacopeia chapter titled "Microbiological examination of non-sterile products-Microbial Enumeration Tests”. USP<61> is a quantitative test that determines the Total Aerobic Microbial Count (TAMC) and Total Yeast and Mold Count (TYMC) present in non-sterile products. The purpose is to provide guidelines and procedures for determining the microbial load present in non-sterile products. This test helps to ensure these products are free from excessive microbial contamination that could harm consumers. This test is commonly performed to check product safety before releasing it to market.

The test involves taking a sample and using specific techniques (like membrane filtration, pour plating, or spread plate methods) to recover microorganisms from the product followed by growing and counting the microorganisms present in the non-sterile product. It helps determine if there are too many microorganisms, which could be harmful to health or affect the quality of the product.

USP <62> Absence Test- Specified Microorganisms

The purpose of USP<62> is to conduct tests to determine the absence of specified objectionable microorganisms in nonsterile products. These microorganisms are considered harmful or potentially pathogenic, and their presence could pose risks to patient health.

USP 62 test is a qualitative test that determines the absence of the specified microorganism in the non-sterile product. If the product has a low count of bacteria, yeast, and mold within the acceptable limit, it can still be harmful if pathogens are present even though they are very low in number. Specific procedures are outlined in USP<62> to detect the presence of these specified microorganisms. This typically involves taking samples and cultivating any microorganisms present using suitable growth media, and then using selective and differential methods to identify and confirm the presence or absence of the specified microorganisms.

The microorganisms that can be tested for absence test include the following:

• Bile-tolerant Gram-negative bacteria
• Escherichia coli
• Salmonella species
• Pseudomonas aeruginosa
• Staphylococcus aureus
• Clostridia species
• Candida albicans