Controlling manufacturing environmental conditions is not only a regulatory requirement but also part of protecting and producing a quality product. Environmental monitoring (EM) of manufacturing facilities provides assurance that the environment is both adequately controlled and in compliance. There is substantial evidence establishing a direct relationship between the level of environmental control and the final quality of the product.
EM serves a critical role in product safety by ensuring that the environment in maintained properly. Swabs are often used for sampling irregular or hard-to-reach surfaces and critical surfaces where contact plates are not practical. In addition, cleaning hold-time studies are often performed using swabs. In general, the purpose of a Microbial EM Program is to: provide crucial information on the quality of the work 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 fulfilled; prevent the risk of contamination of the product; ensure there are environmental controls in the production areas; and provide a profile of the microbial cleanliness of the manufacturing environment.
Most EM is done by plate counting of colonies which is both simple and inexpensive. However, plate counting methods are slow requiring two to seven days to complete, thereby causing a delay in the detection of contamination, which can increase product loss, plant downtime and result in expensive clean up. The delay in obtaining results impacts reaction to contamination issues and can make investigations very difficult. For example, the rooms in question typically have been cleaned numerous times, so re- sampling results are almost always meaningless and determining the root cause of the contamination is difficult. Since real-time response is not possible, batches are jeopardized.
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.
Available RMM Methods
Methods are available to measure total particles in the air, including Total Organic Carbon (TOC), and ATP (Adenosine Tri-phosphate). 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 (Carrick et. al. 2001 and Easter 2010). Therefore, these results do not measure viable organisms in the environment or on production lines. The standard plating methodologies can take several days. Rapid microbiological methods (RMM) can provide rapid and efficient solutions over traditional plating methodologies. Therefore, both manufacturers and regulators are motivated to develop initiatives and help in the implementation of rapid testing methods (FDA 2004).
On June 8th the conference on Contamination Control ( http://www.pdamidwest.org/) the data from the validation of BioLumix growth based system for EM and water testing will be presented. The BioLumix Optical System is based upon the detection of microorganisms due to color or fluorescence changes caused by the growth and metabolic activity of microorganism in the test vials.
Study Design: 10×10 cm surface coupons made out of 5 various materials (Stainless Steel, Aluminum Alloy, High Density Polyethylene, Silicone Rubber, and Perspex, Plexiglas) were inoculated with different organisms (Bacillus spizizenii var subtilis ; Escherichia coli; Pseudomonas aeruginosa; Staphylococcus aureus; Citrobacter freundii; Candida albicans; and A. brasiliensis formerly Aspergillis niger). The coupons were then swabbed and testing using three assays: (i) Total aerobic count; (ii) Yeast and Molds and (iii) Gram Negative Bile Tolerant Bacteria.
In total, 550 coupons were tested, 290 coupons were inoculated above the specified levels while 260 coupons had counts below the specified levels. There was very good correlation between the BioLumix results and the plate count results, with an overall agreement for samples above spec of 97.2%. None of the 260 un-inoculated coupons detected in the BioLumix system or had plate counts above the specified level. Consequently there was 100% agreement between the two methods. The overall agreement between the two methods was 98.5%.
Total Aerobic Count: A total of 129 swabs were analyzed using the BioLumix TAC vial and the standard plate count method with TSA. All the swabs with count above specified level signaled as being above the specified level in the vials. Five marginal samples detected in the vials and had counts just below the specified level. The agreement between the methods was 96.1%.
Yeast and Molds: A total of 85 coupons were analyzed using the BioLumix YM vial and the standard plate count method with SDA (Sabouraud Dextrose Agar W/ Chloramphenicol). All the swabs with count above specified level signaled as being above the specified level in the vials. A few coupons with count very close to the specified level (e. g. 50-80 cfu/swab for a specified level of < 50 cfu/swab) did detect in the vials. One coupon that had a count of 40 cfu/swab, while technically found to be below the specified level, was a very marginal result being so close to the specified level of 50 cfu/swab, did detect in the vial. The agreement between the two methods was 98.8%.
Gram Negative Bile Tolerant Bacteria: A total of 75 coupons were analyzed using the BioLumix ENT vial and the standard plate count method with VRBGA (Violet Red Bile Glucose Agar). One swab with a marginal count of 310 cfu/swab did not detect in the vial. A few coupons with count very close to the specified level (e. g.300-400 cfu/swab for a specified level of < 300 cfu/swab) did detect in the vials. One coupon that had a count of 190 cfu/swab did detect in the vial. The agreement between the two methods was 97.3%.
Conclusion: The BioLumix system was validated as an alternative to the plate count method for EM. The study involved a total of 550 surface coupons representing five diverse types of surface material. These five surfaces represent those encountered in manufacturing, including metal, plastics and rubber. Some of the coupons were inoculated with bacteria or 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.
The advantages offered by the BioLumix system include: automation of results, great speed to results, paperless EM, direct detection of viable microorganisms, detection of multiple types of organisms, increased operation efficiency and consequently an improvement in product quality, reduction in costs, and both enhanced reporting and ability to track trends.
Water is widely used as a raw material, ingredient, and a solvent in the processing, formulation, and manufacture of pharmaceutical products, active pharmaceutical ingredients and intermediates. As such, all water purification systems must be monitored regularly to verify the quality of the water produced. Monitoring of water for microbiological quality may include testing for total heterotrophic plate count, coliforms/E. coli, or by checking for the presence of other organisms suspected to be present in a water sample. The relevant standards relating to pharmaceutical grade water are USP <1231> Water for Pharmaceutical purposes.
The BioLumix system is capable of testing water for heterotrophic bacteria, coliforms, E. coli, and Pseudomonas. For levels of < 1 cfu/ml the water can be inserted directly into the vial. To test for levels such as < 1/100 ml the water is filtered and then the filter is added directly to the vial.
Water study summary: Ninety- two water samples were analyzed with two specified levels (10 cfu/ ml and 100 cfu/ml). Sixty samples were below the specified level by both methods while 28 samples were above the specified level by both methods. Four samples were below the specified level by the BioLumix method, but above by the plate count method. All these samples had very low counts (1-3 colonies on the plate). There was 96.9% agreement between the two methods.
BioLumix advantage for water testing: Final results were seen in the BioLumix system roughly 13 hours earlier than the plate count method using Standard Methods Agar. The BioLumix method can detect organisms at a level of < 1 cfu/mL of water. The BioLumix system is faster, less labor-intensive, and more sensitive than the plate count method.
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
PDA Midwest Chapter- June 8, 2012 – All Day Contamination Control Event (http:// www.pdamidwest.org/)
United States Pharmacopeia XXI (1985) Chapter <1231> Water for Pharmaceutical Purposes. The National Formulary. Rockville, MD, The United States Pharmaceopeial Convention.