Best Practices for Sampling of Pharmaceutical Water: New ISPE Good Practice Guide

Sampling of pharmaceutical water is a required activity that has historically relied on the expertise of those responsible for developing and implementing the sampling procedures and/or plan. Sampling provides proof that a system producing water for pharmaceutical applications is operating under control and that the water being used is of suitable quality for the intended purpose.

Unfortunately, little sampling guidance has been available fr15om regulatory, compendial and other sources until just recently. Previously, the ISPE Critical Utilities Community of Practice (CU-COP) developed and published Baseline and Good Practice Guides for use by those designing, operating, using and/or validating pharmaceutical water systems. In 2012 the CU-COP Steering Committee began exploring the need for a sampling guidance document and shortly thereafter began the arduous task of creating a guidance document that would be comprehensive, useful and informative. That effort resulted in the publication of the “ISPE Good Practice Guide: Sampling for Pharmaceutical Water, Steam and Process Gases” in December 2016.

As described in the title, this Good Practice Guide (GPG) is divided into three sections that address best practices for sampling of pharmaceutical water, pharmaceutical steam and pharmaceutical process gases. The ISPE Boston Area Chapter sponsored a program on February 16, 2017 to introduce this GPG with specific focus on the water and steam chapters. The presentation of the water chapter included a discussion of all the major topics covered within that chapter.

As explained in the water chapter, there are two major contaminants that must be monitored and controlled: chemical contaminants and microbiologic contaminants. The distribution of these contaminants within a system (homogeneous or not) is of great importance to assure sampling accurately reflects the conditions present. The chapter goes on to explain the purposes for sampling, sampling attributes of importance, the differences between sampling for Quality Control (QC) and sampling for Process Control (PC) along with the importance of Alert and Action Levels for Process Control. An extensive discussion of the methodology for QC sampling is also provided to ensure it is understood that QC samples must be representative of the water delivered to manufacturing through any hoses and/or accessories rather than simply from a designated use-point valve.

These key issues have not been extensively discussed in print previously, making them of keen interest not only to those directly involved with sampling but also to those tasked with system design and operational responsibility. Not surprisingly, recent changes published in USP 39, Supplement 2; Informational Chapter <1231> provide added focus on this important topic.

The chapter continues by discussing sampling locations and access as well as development of appropriate and well-designed sampling plans. Dialog extends further to include sampling frequency, sampling methodology including Rapid Microbial Methods (RMM), sampling techniques and training, sample handling and, to a limited extent, sampling records. There is even a discussion about sample valve design, the varied types of sample valves available and the locations appropriate for various types of valves which may be used for sampling. The need to locate sample points appropriately in order to assure sampler safety as well as sample point functionality is emphasized with the recommendation to consider sample point location during system design, taking into account the requirements necessary to assure samples are not compromised.

This latest addition to the ISPE collection of pharmaceutical guides provides much needed industry support, offering technical direction relative to a subject overlooked for far too long. Anyone interested in staying current with pharma water systems best practices should plan to add this guide to their reference library.

To purchase the Good Practice Guide, please visit the ISPE website: https://www2.ispe.org/imis/ISPE/Store/Category_Search_Results.aspx?InitialText=ISPEGPG