Total Organic Carbon (TOC) is a highly powerful analytical chemistry method that is valuable for many types of determinations. Two of the most common uses of Total Organic Carbon testing are for Purified Water testing and Cleaning Validations.  Gibraltar Laboratories excels in these areas because we use state of the art equipment manufactured by Sievers and our scientists are extensively trained and proficient.

Purified Water is water obtained by a suitable process. It is prepared from water complying with the U. S. Environmental Protection Agency National Primary Drinking Water Regulations or with the drinking water regulations of the European Union or of Japan, or with the World Health Organization’s Guidelines for Drinking Water Quality. It contains no added substance. The purity is judged by the absence of trace amounts of organic matter which is measured by the Total Organic Carbon test.

Total Organic Carbon is an indirect measure of organic molecules present in pharmaceutical waters measured as carbon. Organic molecules are introduced into the water from the source water, from purification and distribution system materials, and from biofilm growing in the system. Total Organic Carbon  can also be used as a process control attribute to monitor the performance of unit operations comprising the purification and distribution system. A Total Organic Carbon measurement is not a replacement test for endotoxin or microbiological control. While there can be a qualitative relationship between a food source (TOC) and microbiological activity, there is no direct numerical correlation. In addition to TOC, Purified Water must also meet the requirements of being relatively non-conductive as well as not harboring microbial coliforms such as E. coli. Customers typically rely upon Gibraltar Laboratories to quickly determine if the water they rely upon meets the requirements of purity such as low level of TOC, low conductivity and the absence of coliforms. Because Total Organic Carbon testing is so sensitive special care is needed to sample water. For example, the glassware used to collect the water must be specifically certified for use in TOC analysis or the determination will not be accurate. In addition, glassware used to collect samples must not be exposed to alcohol. Alcohol, such as ethanol, is a very useful step to control microorganisms but its use is detected and produces high TOC determinations leading to unnecessary investigations and/or OOS documentation.

Cleaning validation is performed to demonstrate that a new manufacturing campaign will not be contaminated by ingredients or cleaning agents previously used on common equipment. Since Total Organic Carbon is a non-specific measurement of carbon, it has wide spread application for companies that must comply with regulatory requirements. Typically, the manufacturer must assure that the active ingredients, excipients and cleaning agents used in a previous process are effectively removed so as to not be present as contaminants in a subsequent process. Since TOC can detect levels in the part per billion range it is possible to demonstrate that the equipment is not just visually clean but that it is clean scrupulously clean.

Gibraltar Laboratories is available to help and assist you to write validation protocols and reports to meet your needs. Please contact us for more information on Total Organic Carbon and other testing laboratory services.

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  1. What are your prices for TOC samples? What are the detection limits of your instruments? Will the detect less than 20 ppb TOC/

  2. We held TOC water samples for longer than 28 days(acidified and refrigerated) before they were tested. What are the potential consequences in obtaining an accurate TOC result? If the sample results show compliance with the USP requirement for TOC in purified water, is there a reason to suspect that TOC initially present in the sample degraded or is otherwise not measurable at the time of testing?

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