A useful introduction

XIV

trends in analytical chemistry, vol. 1, no. 6,1982

A useful introduction Monitoring Toxic Gases in the Atmosphere for Hygiene and Pollution Control, by William Thain, Pergamon Press, 1980 $25.00 (xv + 159pages) ISBNOO80238106

The regulations to limit concentrations of airborne chemical contaminants in the atmospheres of chemical plants and factories are becoming increasingly stringent in many countries. There is therefore a need for accurate and sensitive methods of monitoring trace concentrations of gaseous contaminants in air to ensure that they are kept within acceptable levels. In this book the author aims to provide a basic insight into the principles of atmospheric monitoring of gases and vapours. He also discusses the types of sampling equipment used and indicates where and when problems in sampling can occur. The book

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does not attempt to detail methods for measuring or sampling specific compounds and it is assumed throughout that the reader has a knowledge of the analytical techniques involved (principally chromatography, spectrophotometry and calorimetry). The first three chapters give a basic introduction to the measurement of toxic hazards along with an outline of the measurement techniques employed for area and personal monitoring and an account of the errors that can occur. Chapter 4 discusses the merits of calorimetric indicating tubes and paper tapes and the factors that control the accuracy of measurement by these systems. Chapters 5, 6 and 7 deal with the various sample collection methods available, and discuss the different types of pumped and diffusive sampling systems and the factors that affect their performance in practice. The final chapters cover the methods

of calibration and testing of monitoring procedures and the statistical treatment of data; they also look forward to future developments in atmospheric monitoring. The reviewer has one adverse comment. The lists of references at the end of each chapter are far from extensive and include a number of rather obscure titles that could prove difficult to obtain. Reference to established texts on several of the subjects discussed is omitted. Overall the book achieves its aims. The presentation is good with each section clearly defined, logically laid out and readable. It should be regarded as an introductory text and should be useful to analysts entering this field for the first time. C. J. PURNELL

The author of the review is at the Occupational Medicine and Hygiene Laboratories of the Health and Safe0 Executive, 403 Edgware Road, London NW2 6L.N, U.K.

Weird but not wonderful Optimization in HPLC, by R. E. Kaiser and E. Oelrich, Hiithig, 1981. $33.00/ DM66.m (ix + 269 pages) ISBN 3 7785 0657 9

The title of this small volume is intriguing, inasmuch as HPLC optimization is currently a ‘hot’ topic. However, the contents of the book will certainly surprise most readers, who would have expected some connection with the large and growing literature on this subject. It is in fact the authors’ contention that most HPLC separations are unsatisfactory because of poor equipment or other sources of extra-column band broadening. Consequently, the first 180 pages are given over to an empirical scheme (the abt concept) for confirming such extracolumn losses in column efficiency, as well as to novel (if inconvenient) techniques for solving this ‘problem’. The second hundred pages are a description of special hardware developed by one of the authors (‘separation cassettes’), which is intended to provide certain advantages - not least, the minimization of extra-column effects. The style of the first part of the book

(by Kaiser) can best be described as ‘weird’. It is a mind-bending combination of polemic, mathematical equations, and very little practical information. Few people (other than a hapless reviewer) will have the fortitude to persevere to whatever conclusions might be extracted from this material. Kaiser’s primary goal seems to be to provide a justification for his abt concept, which was first proposed for gas chromatography. This concept comes across in .the present book as an empirical treatment that has been attacked by many of the ‘big names’ in chromatography. Attempts to justify this approach for HPLC are based on the improvement (by various gimmicks) of an HPLC separation that is initially poor and obviously suffering from severe extra-column effects. In my own experience, I have not seen such bad chromatograms with equipment operated in the usual fashion, although similar examples were not uncommon 5 years ago. Today, with equipment now sold, competent users can avoid extra-column effects without recourse to any of the strategies propounded here. The second half of the book resembles nothing so much as the commercial material that is disseminated by

manufacturers to sell HPLC equipment. This section blends pages of catalog-like descriptions of the separation cassettes with applications resembling those shown in various ‘newsletters’, ‘bulletins’, etc. Some of this discussion for column-switching is interesting, although somewhat outdated by the recent upswing in papers on this technique. The cassettes are also recommended for use with micro-columns, which represent another area of current interest. However, it is not clear to what extent the off-the-shelf cassettes can be used in this fashion, without custom modifications. This second half of the book has been adequately summarized by the authors: ‘It should be mentioned . . . that all the chromatographic techniques considered (here) can also be adopted without use of separation cassettes’. I cannot recommend the purchase of this book by either individuals or libraries. L. R. SNYDER

The author of the review is principal scientist in the clinical chemistry division of Technicon Instruments Corp., Tarrytown, NY 10591, U.S.A.