An Unfocused Handbook on Environmental Monitoring

Environmental monitoring provides additional assurance that a drug product has been manufactured in an environment of appropriate microbiological quality. This procedure is especially important in aseptic processing, which does not include terminal sterilization of the finished product.

Jeanne Moldenhauer, a recognized authority on environmental monitoring, has edited a series of books on the topic. Moldenhauer assembled a distinguished panel of experts to write the chapters that make up A Comprehensive Handbook (Vol. 4).

It is quite disappointing, however, to note the many shortcomings in the text, some of which are more serious than others. Although the book collects interesting chapters about environmental monitoring, it lacks an overarching theme or organization. If the editor had written an introductory chapter that linked the book's subtopics and explained the rationale for including them in the book, readers would have benefited. Moldenhauer also could have organized the sequence of chapters better so that a consistent thread ran through the book in a rational way.

The book's emphasis on a risk-management approach to environmental monitoring, which is based on guidelines from the International Conference on Harmonization and the US Food and Drug Administration, also is problematic. The risk-based approach is a product of manufacturers' desire to reduce the cost of quality. It is a method of identifying risks and attempting to mitigate them or plan contingencies before the risks materialize. Personnel develop a risk-management program when their environmental-monitoring program is in the planning stage. If the environmental monitoring program detects unacceptable conditions, it can trigger contingencies.

Each chapter that discusses risk management seems to show a grave misunderstanding of the subject. Risk management includes positive risks (i.e., opportunities) and negative risks (i.e., threats). The process includes the identification of risks, the assessment of risks, the prioritization of risks, the development of risk responses, and risk monitoring. Environmental monitoring is a small part of overall risk management. The authors add unnecessary complexity to the topic that could increase the cost of the environmental-quality program rather than decrease it.

Parts of the book contain helpful information about risk management, however. For example, one author observes that environmental monitoring is not a risk-prevention tool, but a risk-monitoring tool. Chapter 8 offers an interesting discussion of risk management and of how personnel can apply various risk-management approaches to sterile production. The reader is directed to these discussions because they cover the topic more comprehensively than do the other chapters.

In addition to the book's broader problems, many chapters have their own particular flaws. The first chapter, titled "Designing and Validating a Contamination Control Program," contains abundant information that would fascinate a newly minted microbiologist. A veteran environmental microbiologist, however, is likely to find the chapter tedious because it covers many subjects that are not directly related to the chapter's ostensible focus.

The chapters that describe the "Lean Microbiology Laboratory" and that offer "Observations in Support of Lean Microbial Identifications" illustrate how Lean concepts can reduce the cost of environmental-monitoring programs. It is both unfortunate and timely that the authors cite Toyota for its Lean approach to quality in view of the massive quality problems that this approach seems to have brought the company.

The Lean laboratory likely will go the way of quality-control circles, which fell out of favor to be replaced first by Six Sigma, then by other alphabet-soup programs. The book extends Lean concepts to the various functions of the microbiology laboratory (e.g., microbial identification) through a discussion of standardizing procedures and protocols for identification. Because automated equipment and rapid methods have increased the productivity of microbial identification, companies tend to request the identification of more environmental microorganisms than before, regardless of whether the identifications are useful. The cost of identification using the Lean approach therefore will increase because it is based on the number of samples processed.

Bengt Ljungqvist and Berit Reinsmüller, two well-known and respected environmental scientists, provided one of the book's best chapters, titled "Collection Efficiency of Microbiological Impaction Air Samples." This well-written and informative chapter increases the reader's understanding of the dynamic of air sampling using impaction samplers. But the chapter should have discussed the mechanisms of controversial air-monitoring systems such as settling plates because many laboratories use them.

One chapter provides a sample of Warning Letters related to environmental monitoring that FDA issued between 2005 and 2010. Although the section is interesting, the author could have provided more context. A review of Warning Letters from the 1980s, for example, would have shown that companies are repeating the same infractions ad infinitum.

Chapter 10 is puzzling because it appears simply to be an unpaid advertisement for Sartorius's gel filters. A more appropriate inclusion would have been a comparative study of filters used in environmental monitoring. Data could have indicated to readers the value, strengths, and weaknesses of various filters for their intended purposes.

The final chapter describes how to identify microorganisms through Fourier transform infrared (FTIR) spectroscopy. Despite the author's claims to the contrary, the technique is far from simple. It also might not be cost efficient because it requires skilled technicians and a large outlay of funds to purchase equipment. FTIR spectroscopy might not yet be ready for adoption by quality-assurance microbiology laboratories.

Unfortunately, the book does not live up to its description as a comprehensive handbook. It does, however, present valuable information. But the unfocused nature of this volume detracts from the main purpose of the series of books, which is the control of the manufacturing environment.

Roger Dabbah is a principal consultant at Tri-Intersect Solutions and an associate professor of technology and engineering management at the University of Maryland, University College, Graduate School, College Park, MD 20742, tel. 301.762.9258, fax 301.762.5356, rdabbah@verizon.net He is also a member of Pharmaceutical Technology's Editorial Advisory Board.