Cosmetic Microbiology Testing

At Orivida Research, we provide microbiological testing services to help cosmetic and personal care brands evaluate preservative effectiveness, microbial contamination, and product quality. Our testing services support formulation development, quality control, and product safety assessments using established United States Pharmacopeia (USP) methods.

Preservative Efficacy Testing (PET) – USP <51>

Preservative Efficacy Testing (PET), also known as Challenge Testing, evaluates the ability of a cosmetic formulation's preservative system to control microbial contamination. During testing, the product is inoculated with specified microorganisms, and microbial survival is monitored over a defined period to determine the effectiveness of the preservative system.

PET is particularly important for water-based cosmetic formulations, including creams, lotions, shampoos, conditioners, and other products susceptible to microbial contamination.

Testing helps brands evaluate the effectiveness of preservative systems, identify potential microbial contamination risks, and support product safety and quality assessments.

Microbial Enumeration Testing – USP <61>

USP <61> is a quantitative microbiological test used to determine the number of viable microorganisms present in a product. Testing includes Total Aerobic Microbial Count (TAMC) and Total Combined Yeasts and Molds Count (TYMC).

This testing helps cosmetic manufacturers evaluate the microbiological quality of raw materials and finished products, monitor manufacturing consistency, and determine whether products meet established microbial specifications.

USP <61> is commonly used for routine quality control, batch release testing, and investigations of potential microbial contamination.

Tests for Specified Microorganisms – USP <62>

USP <62> is a qualitative microbiological test designed to detect the presence or absence of specified microorganisms in a product. Unlike USP <61>, which measures microbial counts, USP <62> focuses on identifying particular microorganisms that may present a concern for product quality and consumer safety.

Depending on the testing requirements, microorganisms evaluated may include Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans.

This testing helps brands verify that finished products meet microbiological specifications and provides important information for quality control and product safety assessments.

Burkholderia cepacia Complex Testing – USP <60>

USP <60> evaluates the presence or absence of Burkholderia cepacia complex (Bcc), a group of bacteria commonly found in water and moist environments. These microorganisms can survive in low-nutrient conditions and may exhibit resistance to certain preservatives, making them a concern for water-based cosmetic and personal care products.

Contaminated water systems are a major potential source of Bcc contamination in cosmetic manufacturing. The bacteria can enter formulations through manufacturing water, raw materials, or equipment and may persist in water systems through biofilm formation.

USP <60> testing helps manufacturers detect Bcc contamination, assess microbiological quality, and support product safety and quality control programs.

Water Activity Testing (aw)

Water activity testing measures the amount of available water in a cosmetic formulation that can support microbial growth. Unlike moisture content, which measures the total amount of water present, water activity determines how much water is available for microorganisms to grow and multiply.

Water activity is an important factor in evaluating the microbiological stability of cosmetic products, particularly anhydrous formulations, powders, balms, and other low-water formulations. A water activity (aw) of 0.60 or below is generally considered insufficient to support microbial growth.

Water activity testing helps cosmetic brands assess microbial growth potential, evaluate formulation stability, and make informed decisions regarding preservative requirements and product safety.