Occupational and environmental exposure to bioaerosols from composts and potential health effects - A critical review of published data

The primary objective of this study was to critically review published literature related to studies of airborne microorganisms or their constituent parts (bioaerosols) associated with organic waste composting facilities, and to establish whether there is a risk to worker health from the inhalation of these bioaerosols. The review aimed to identify the personnel at risk on compost sites, identify the circumstances which increased the risk and indicate suitable control measures to control the risk. A further consideration was that airborne dispersal of bioaerosols from compost facilities could affect neighbouring facilities or residents, leading to health concerns, and the review also looked at evidence of bioaerosol dissemination from sites, potential exposures and reported ill health. Further objectives were to review computational modelling tools for estimating dispersion of bioaerosols from composting facilities and to recommend suitable models. Existing experimental data, previously derived from environmental sampling at composting sites by the Composting Association who collaborated on this project, were reexamined to provide comparison between experimental and modelled data. This report and the work it describes were funded by the Health and Safety Executive (HSE). Its contents, including any opinions and/or conclusions expressed, are those of the authors alone and do not necessarily reflect HSE policy. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photocopying, recording or otherwise) without the prior written permission of the copyright owner. ii CONTENTS 1 Introduction 1 7 Reported studies of bioaerosols generated by composting activities and potential human exposure 2 Purpose of the Review 3 3 Composting Practices 7 4 Microbiology of the composting process 10 5 Bioaerosol components and hazard to human health 14 6 Potential ill health effects among compost workers 21 23 8 Ambient bioaerosol levels, bioaerosols from other industries and dispersal 9 Potential use of computational modelling to estimate bioaerosol dispersion from compost sites 32 from composting 42 10 Reports of Ill health associated with exposure to compost bioaerosols 55 11 Discussion and conclusions 66 12 Summary and recommendations for further study 73 13 Appendices 77 14 References 95 iii iv EXECUTIVE SUMMARY OBJECTIVES The primary objective of this study was to critically review published literature related to studies of airborne microorganisms or their constituent parts (bioaerosols) associated with organic waste composting facilities, and to establish whether there is a risk to worker health from …