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Book Review: Airborne Pollutants in Museums, Galleries and Archives

tors a great deal. This is not always because they have identified huge problems relating to air pollution, but rather a function of the issues being poorly understood or that air pollutants are rarely monitored. There are few books on the subject and it has often been relegated to chapters in more general textbooks on the protection of indoor heritage. Gary Thomson’s classic The Museum Environment reflects the situation long ago, while Appelbaum’s Guide to Environmental Protection of Collections seems uncomfortable with air pollution. The team at the Bartlett School in London produced Guidelines on Pollution Control in Museum Buildings in 2000 and this has been developed with European colleagues as part of their IMPACT model (http://www.ucl.ac.uk/sustainableheritage/impact/). Despite this more recent material there is undoubtedly a need for a new contribution, so Airborne Pollutants in Museums, Galleries and Archives should prove a very useful book. I read it with much enthusiasm and appreciation for what Jean Tétreault has done. It wisely restricts itself to a narrow range of pollutants that are identified as critical to museums. As the book’s subtitle suggests, it is concerned with ‘risk assessment, control strategies and preservation management’. Thus the air pollutants are treated rather quickly in the first chapter with little time to consider the complexity of indoor sources or the emerging understanding of the chemistry of indoor air. The following chapter deals with the quantification of the exposure effect relationship and the work moves on to risk assessment and control strategies, preservation management and then to monitoring. The appendices contain some 40 pages of tables which will be particularly valuable for those with more exacting concerns about air pollution in museums. The monitoring section rightly gives precedence to the passive and time-averaging approaches to monitoring air pollutants in the cultural environment. Although the chapter is very detailed it may well be too brief to give the general reader a good understanding of how to approach museum monitoring. At times it is tantalising without the author revealing what he thinks. He suggests new measurement techniques will soon replace those of the 1980s and 1990s, but we find few clues as to what these might be. Cheap, robust, sensitive, unobtrusive sensors for pollutants of concern seem still to elude us. Perhaps the most notable idea within this book is the NOAEL/LOAED concepts. Jean Tétreault has been developing these for a number of years. These acronyms represent the ‘no observed adverse effect level’ and the ‘lowest observed adverse effect dose’. The ideas seem to have grown more sophisticated since I first encountered them. NOAEL emerges in this book as a more theoretical concept that can be determined as much from thermodynamics as experiment. LOAED is more based on cumulative dose. Philosophically there is an uneasy relationship between these concepts and the notion of thresholds; a relationship that the book hints at, but never quite teases out. The concepts require us to acknowledge the notion of thresholds (particularly in the case on NOAEL) while on the other hand utilise the ‘linear-reciprocity’ principle. However, thresholds represent a breakdown of ‘linear-reciprocity’ so we enter into difficult territory, which makes it hard to think about what we are doing when extrapolating effect levels and doses to different values. A parallel problem arises when we try to use the Arrhenius relationship to extrapolate reaction rates from high temperatures to much lower ones. Setting appropriate levels of exposure to pollutants remains a difficult area, so the NOAEL or