PREFACE
While much of the concern about air pollution in the past has been focused on the outdoor environment, in recent years indoor air quality (IAQ) has moved up the agenda. Over the period between 1987 and 1999, more than $1 billion of federal government money was spent on research into indoor air pollution in USA. In March 2000 the Environmental Protection Agency released a report on "Healthy Buildings, Healthy People: A Vision for the 21 st Century", which set the objective of achieving major health gains by improving indoor environments. The National Institute for Occupational Health (CDC) has studied the impact of poor indoor air quality on productivity. The median estimate of these losses is $100 billion per year. Other countries, including Canada, Denmark, Finland, Netherlands and Sweden also have substantial programmes on residential housing and health. However, there is wide variation in the research effort and expenditure on measures to improve IAQ, and IAQ in some is very much lower on the order of priorities.
A document produced in July 2000 by a WHO European working group has further emphasized the global importance of IAQ as a determinant of population health and well being. This document, "The Right to Healthy Indoor Air", sets out nine principles (derived from the general principles in the International Bill of Human Rights). These are intended to inform all those who have an influence on public health of their obligations to honour the right of every individual to breathe healthy indoor air, and influence those national governments that do not have plans for future action on healthy indoor air to put it on their agenda.
Despite the large amount of money spent on research into pollution of the indoor environment, the US General Accounting Office has confirmed that what has been done has pointed to the complexity of the problem and to major gaps in knowledge. Among these gaps are accurate knowledge of the identities and sources of pollutants and of the effects of prolonged exposure to indoor pollutants on health. This book considers one such group of pollutants, namely microorganisms, and more particularly heterotrophic bacteria and fungi. Advances have certainly been made in our knowledge of microorganisms in the home and indoor work environment as research has accelerated in the last decade. Fully elucidating their effects on human health has however been bedevilled by problems of accurate assessment of exposure to microorganisms and precise identification of those present in the environment. The first three sections of the book review the types of microorganism in outdoor and indoor air, their growth and control in home and work environments, and their role in respiratory disease. The remaining sections of the book are given over to addressing the twin problems of exposure assessment and identification, discussing the methodology for and conduct of investigations of indoor environments and providing keys and co-lour illustrations to assist in the identification of approaching 100 mould, yeast and actinomycete contaminants.
We think that the availability of information on the microorganisms that grow in the built environment, together with information on the limitations of the methods currently available to measure them, will be useful to researchers, public health officials and industrial hygienists. Together with reviewers, the authors from Canada, Sweden, the Netherlands, the United Kingdom and USA have worked hard to produce material that is accurate and timely. In addition to thanking reviewers and authors for their efforts, we should also like to express our gratitude to Margaret Flannigan for editorial assistance, Karin van den Tweel for helping with the drawings and Ans Spaapen-de Veer for preparing the index. Thanks are given to Dr Brian Crook (HSL, Sheffield, UK) for substantive assistance in the preparation of Chapters 3.2.
We have dedicated this book to the memory of a fellow microbiologist, John Lacey, who was internationally recognized for his unique expertise at the interface of stored product microbiology, aerobiology, occupational hygiene and medicine, and was the author of more than 300 publications. The aerobiological, taxonomic and ecological studies of John and his co-workers not only clarified the role of microorganisms in a number of occupational lung diseases, but have a relevance to home and non-industrial work environments as well as to the storage and processing of the particular agricultural materials with which they were first concerned. In his friendly collaboration and links with many workers in overseas institutes, he was generous in passing on his knowledge and expertise to others, and his work and the influence that he has had are reflected in this book.
Brian Flannigan (Edinburgh)
Robert A.Samson (Utrecht)
J.David Miller (Ottawa) |