Letters
to
the
Editor
Performance-based tion efficiency of a contaminant caused by Mixing business with tenure methods lot variability of the sampling medium, I read with interest the recent article on A recent issue of Analytical Chemistry car- should be verified by the laboratory doing academic trends toward entrepreneurship the analysis. With the performance-based ("Mixing Business with Tenure", May 1, ried a news article about the introduction method approach, there can be more than 1996, p. 311 A). My experiences involving of a congressional bill to "accelerate the one method for a particular analyte, and technology transfer and the formation of move toward performance-based analytimethods can be updated without rewriting my business, Advanced BioAnalytical Sercal methods" for EPA ("Performanceregulations. vices, parallel very closely those described Based Methods," Feb. 1,1996, p. 83 A). We would like to point out that the NaThe argument that performance-based in your article. I am happy to report mat Cornell has progressed from considerable tional Institute for Occupational Safety methods may be more open to legal chalskepticism to a relatively high comfort level and Health (NIOSH) has followed the phi- lenge must be considered in light of the with my business activities. In fact, they are losophy of developing performance-based rigorous statistical treatment of the beginning to refer to my example as a methods for monitoring the workplace method evaluation data. When the use of environment for over 20 years. a method is mandated by law, the method model of the way professors can serve both roles with mutually beneficial opportunities. defines the "true concentration," and in NIOSH (and the Occupational Safety Jack Henion essence, the "true concentration" is that and Health Administration) methods are Cornell University and Advanced measured by the method. However, all evaluated according to a set of criteria. BioAnalytical Services, Inc. methods have inherent variability and The status of each NIOSH method with therefore the "true concentration" will respect to those criteria is noted in the also have variability. With the perforNIOSH Manual ofAnalytical Methods Your recent feature on "Mixing Business mance-based method approach, this vari(NMAM, DHHS Pub. #94-113). It should with Tenure" puts a rather positive spin be noted that these methods are only rec- ability in the method result is recognized on what many view as a questionable pracand is incorporated into the method evalu- tice. Such arrangements may be an attracommendations and their use is not manation criteria. dated by law. The latest revision of the tive deal for the professor, but are often a method evaluation guidelines and criteria Faustian bargain for the students inIn the case of NIOSH methods, the is available from NIOSH Publications volved. They are shortchanged by having accuracy criterion states that an accept(4676 Columbia Parkway, Cincinnati, OH a part-time mentor and may have some able method must produce a result that is 45226) as Guidelines for Air Sampling and within ±25% of the true concentration 95% career options compromised. Analytical Method Development and Evaluof the time with 95% confidence. In the Garry A. Rechnitz ation (DHHS Pub. #95-117). current versions of NMAM and the evaluUniversity of Hawaii at Manoa ation guidelines, the accuracy of the Performance-based methods, as the method is estimated based on results obarticle states, allow greater flexibility and tained by defined experiments. This prothe opportunity to use newer technology. Letters to the Editor vides the end user with more flexibility in Along with thisflexibilityto adapt and We welcome your comments remethod selection, based on the needs of modify the methodology comes the regarding published articles or other sponsibility of each laboratory to establish the monitoring situation. that a method meets the appropriate pertopics of interest to analytical When ensuring compliance with an formance criteria. Usually, the primary chemists. Letters may be submitexposure standard is the goal, use of the criterion is a specified accuracy level, almost accurate method is desired. The key ted by e-mail (
[email protected]), though other factors (such as the limits of issue in this instance is to ensure that the fax (202-872-4574), or regular detection and quantitation, sample storage worker is not overexposed to the contamimail (Analytical Chemistry, stability, etc.) may be just as important. If nant being monitored and that one's ACS, 1155 16th St, N.W., Washa laboratory is using a method evaluated health is not being compromised. ington, DC 20036). Please by NIOSH, it is reasonable to assume that Martin T. Abell include your full address, signacertain tests, such as sample storage staEugene R. Kennedy ture, and daytime phone number. bility, need not be repeated. However, Methods Research Branch Letters should be brief and may other factors that may be dependent on National Institute for be edited for clarity or space. situations beyond the control of the Occupational Safety and Health method, such as changes in the desorpWashington, DC Analytical Chemistry News & Features, August 1, 1996 459 A
