Putting together an environmental monitoring plan requires a thoughtful, scientific approach establishing and considering the risks of contamination from each location along the manufacturing process.
WHY MONITOR THE ENVIRONMENT?
Environmental monitoring (EM) is a basic requirement across many regulated industries such as food, cosmetics, Nutraceutical, dietary supplements, and pharmaceuticals. It measures the degree of maintaining environmental control and, therefore, the safety of the manufactured products. Maintaining environmental control can prevent product contamination.
The FDA evaluates the environment of manufacturing facilities against the regulatory code, and the potential of the product allowing for growth of organisms. They expect manufacturers to be in control of the environmental conditions in their facility. There is evidence that a relationship exists between the level of environmental control and the final quality of the product. In product safety, the EM program serves a critical role that the environment is under appropriate control.
In manufacturing facilities, there is a need to demonstrate that production equipment is sufficiently clean thereby the next production lots are not contaminated from the material of the previous lot.
An effective sampling plan needs to be established, the purpose of a microbial EM program is to:
• Provide crucial information on the quality of the work process environment during manufacturing
• Prevent future microbial contamination by detecting and reacting to adverse trends
• Prevent the release of a potentially contaminated batch if the appropriate standards are not met
• Prevent the risk of contamination of the product
• Ensure there are environmental controls in the production areas
• Provide a profile of of the microbial cleanliness of the manufacturing environment.
SITE SELECTION FOR DATA COLLECTION
The site’s selection for data collection should show the effectiveness of cleaning. Such as:
• Site where the product is exposed to people and equipment
• Critical sites that can change product integrity if compromised
• Areas and processes steps where microbial contamination must not happen, such as the final filling of the product into its containers.
In establishing an EM plan, the number and location for sampling sites should be established. When choosing the sampling sites, there needs to be a good representation of risk-based sites where the environment can affect the product quality. Examples of such location include areas that are difficult to clean, or areas close to critical operations.
For sterile products, the manufacturer needs to keep the bioburden of the pre-sterilization as low as possible. There is a need to monitor the air, water, personnel, and surfaces as they all can contribute to the bioburden.
For non-sterile, low bioburden products, there are two main reasons for monitoring the environment:
1. To keep product bioburden under control
2. To know if the environmental isolates could contain objectionable organisms.
Other important questions to consider include:
? What is the antimicrobial effectiveness of the product?
? Will the product promote microbial growth?
? If so, which organisms can grow and get around the inhibitors build into the products?
ESTABLISH A BASELINE
Before initiating an EM program, it is recommended to get a baseline of total aerobic count, Yeast and mold count, perhaps coliform or Enterobacteriaceae, and in some instances lack of objectionable organisms on surfaces and the air. Establishing a baseline also allows for assessments of the types of organisms present, and helps in developing a scientifically sound disinfection program to address chemical kill and physical removal of such contaminants. The data subsequently collected during microbiological performance qualification, and routine monitoring helps to validate the efficacy of disinfection and cleaning procedures.
CHOOSE SUITABLE METHOD FOR EM
Most EM is done by plate counting of colonies on agar media, which is simple and inexpensive. However, plate count methods are slow, requiring two to seven days to complete, thereby causing a delay in the detection of contamination, which can lead to an increase in product loss, plant downtime and expensive cleanup. Delays can cause increasing inventory holding cost. The delay in obtaining results impacts reaction to contamination issues and can make investigations very difficult. The plate count methodology is also labor-intensive and requires manual data entry and documentation. Such documentation is prone to human errors and compliance issues.
Methods are available to measure total particles in the air, including Total Organic Carbon (TOC), and Adenosine Tri-phosphate (ATP).These methods are very fast to perform but do not correlate well with total bacterial count or any specific group of organisms, and do not measure viable organisms (Carricket al., 2001; Easter, 2010). Therefore, these results do not measure viable organisms in the environment or on production lines.
The BioLumix system is useful for rapid and simple monitoring of the manufacturing environment. A large validation study was performed (Eden and Brideau 2012) to show that is correlates well with the plate count method. The BioLumix system was validated as an alternative to the plate count method for EM. The study involved 549 surface coupons representing five diverse types of material. These five surfaces represent those encountered in manufacturing, including metal, plastics and rubber. Some of the coupons were inoculated with bacteria, yeast, or mold. There was 100% agreement between BioLumix assay and the plate count assay for the 260 coupons that were determined to be below the specified level by the plate count method. There was an overall agreement of 97.2%between the two methods when swabs containing counts above the specified level were used. In general, discrepancies in swab results between the BioLumix vial method and the traditional plate count method reflected marginal samples that were very close to the specified testing level, and thus were variable.
Carrick, K, Barney M, Navarro, A. and Ryder D. (2001). The Comparison of Four Bioluminometers and Their Swab Kits for Instant Hygiene Monitoring and Detection of Microorganisms in the Brewery. J. Institute of Brewing 107, 32-37
Easter M. (2010) A comparison of commercial ATP hygiene monitoring systems. Next Generation Food issue 9, 2010.
Eden, R. and Brideau, R. (2012). Validation of a Rapid System for Environmental Monitoring and Water Testing. In Environmental Monitoring Volume 6, Jeanne Moldenhauer, Ed