RR797 - Investigation of potential exposure to carcinogens ...

1 Executive Health and Safety Investigation of potential exposure to carcinogens and respiratory sensitisers during thermal processing of plastics Prepared by Health and Safety Laboratory for the Health and Safety Executive 2010 RR797 Research Report Executive Health and Safety Investigation of potential exposure to carcinogens and respiratory sensitisers during thermal processing of plastics John Unwin, Chris Keen & Matthew Coldwell Health and Safety Laboratory Harpur Hill Buxton Derbyshire SK17 9JN This work was carried out in support of HSE s FIT3 Disease Reduction Programme Cancer Project s aim to develop a strategy to reduce the incidence of occupational cancer in Great Britain. As part of this strategy, HSE has initiated research that aims to deliver evidence that will help to identify carcinogens of concern, improve control of exposure to carcinogens at work and provide a baseline for evaluating strategies for intervention.

2 Earlier, in 2005-7, HSL characterised the exposure profiles of a selected group of occupational carcinogens and determined baseline exposures with which to compare future levels. The project identified the potential for exposure to carcinogens in the thermoplastic processing and finishing industries however there was a scarcity of published quantitative exposure data. A number of laboratory and other studies had shown that carcinogens could be generated from the processing of thermoplastics in some situations but further Investigation was required to establish the levels of exposure that may originate in the industrial setting. The report describes the results of sampling for carcinogens and respiratory sensitisers at ten large processing plants. The measurement strategy used was sufficiently broad in scope to take into account the presence of respiratory sensitisers and respiratory irritants as well as carcinogens .

3 The findings demonstrate that compliance with HSE guidance achieves adequate prevention and control of exposure in the common thermoplastic processes considered. This report will be helpful to smaller plants operated by small and medium enterprises who undertake the same processes albeit on a smaller scale. 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. HSE Books Crown copyright 2010 First published 2010 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.

4 Applications for reproduction should be made in writing to: Licensing Division, Her Majesty s Stationery Office, St Clements House, 2-16 Colegate, Norwich NR3 1BQ or by e-mail to ii CONTENTS 1 INTRODUCTION ..1 2 ENGAGEMENT OF INDUSTRY 3 SITE Range of sites Measurement protocol ..7 4 Site 1 PVC compounding and Site 2 PE and PP extrusion and blown Site 3 PE and recycled PE extrusion and blown Site 4 PE, PP, PS recycling and Site 5 PET extrusion and blow injection Site 6 ABS vacuum forming of Site 7 PVC Site 8 EPS blow moulding and hot wire cutting ..16 Site 9 -PVC/chlorinated PVC alloy thermoforming ..17 Site 10 PVC 5 Materials and processes investigated ..20 6 Main findings from the measurement survey ..23 Adequacy of Control 7 8 APPENDIX 1 ADDITIVES AND DEGRADATION 9 APPENDIX 2 -AIR MONITORING 10 APPENDIX 2 -SAMPLING AND ANALYTICAL Low volume sampling.

5 40 High volume sampling ..40 iii iv EXECUTIVE SUMMARY This work was carried out in support of HSE s FIT3 Disease Reduction Programme Cancer Project s aim to develop a strategy to reduce the incidence of occupational cancer in Great Britain. As part of this strategy, HSE has initiated research that aims to deliver evidence that will help to identify carcinogens of concern, improve control of exposure to carcinogens at work and provide a baseline for evaluating strategies for intervention. Earlier, in 2005-7, HSL characterised the exposure profiles of a selected group of occupational carcinogens and determined baseline exposures with which to compare future levels. The project identified the potential for exposure to carcinogens in the thermoplastic processing and finishing industries however there was a scarcity of published quantitative exposure data.

6 A number of laboratory and other studies had shown that carcinogens could be generated from the processing of thermoplastics in some situations but further Investigation was required to establish the levels of exposure that may originate in the industrial setting. This study will also inform a parallel programme of work on respiratory disease because the measurement strategy used was sufficiently broad in scope to take into account the presence of respiratory sensitisers and respiratory irritants as well as carcinogens . Objectives To make relevant industry contacts and scope out key areas of the thermoplastic processing to select a suitable number of workplaces to visit To investigate the selected sites and carry out screening measurements for carcinogens and respiratory sensitisers Carry out occupational hygiene assessments for each process investigated.

7 To assess the analytical data and determine the potential for exposure to carcinogens and respiratory sensitisers across the thermoplastics processing sector. Main Findings The levels of carcinogens detected in the process fume at the sites investigated were found to be either low or not detectable. Where low levels of carcinogens or potential respiratory sensitisers were found these were at concentrations 2 3 orders of magnitude below any respective WEL. The maximum concentrations of carcinogens found at the sites visited were: benzene 3(R45) 11 ppb; formaldehyde (R40) 9 g/m; naphthalene (IARC 2B) < 100 ng/m3; and, other carcinogenic polycyclic aromatic hydrocarbons (IARC 1, 2A and 2B) all < 1 ng/m3. All substances detected in this study were measured at levels below 10% of their respective WEL, demonstrating the low levels of process fume encountered.

8 The low levels of total inhalable particulate measured (values from all sites were below mg/m3) and the low concentration of all other substances measured, demonstrates v the low levels of fume generated and the effective temperature control of the respective thermal processing operations. A notable absence of monomers was found in the process fume, which is often a predictor of polymer degradation, and further supports the evidence for good temperature control and minimal generation of process fume at the sites investigated. At the majority of sites it was not always possible to clearly separate background environmental levels of contaminants from those generated from other procedures carried out at the site and those generated from the thermal processing activity of interest due to the low concentrations found.

9 No known respiratory sensitisers (R42) were found at any of the sites investigated. Where low levels of respiratory irritants such as aldehydes, ketones and hydrochloric acid were found these were at concentrations 2 3 orders of magnitude below any respective WEL. The principal exposure controls employed at the sites investigated were a combination of process temperature control and forced mechanical dilution ventilation. Most processes at the sites investigated required very little operator intervention, which in itself reduced exposure risk. The use of LEV and RPE to control exposures to airborne contaminants generated by thermoforming processes was not commonplace at the sites visited. The measurement results indicate that no carcinogens , respiratory sensitisers or respiratory irritants were detected at levels of concern at any of the sites visited.

10 This indicates that the strategies employed are adequate to control the risks associated with exposure to these agents. Recommendations The report describes the results of sampling for carcinogens and respiratory sensitisers at 10 large processing plants. It is recognised that these plants are not fully representative of the whole of the plastics processing sector which includes a large number of SMEs. However, the findings demonstrate that compliance with HSE guidance (HSE, 2002) achieves adequate prevention and control of exposure in the common thermoplastics processes considered. It will therefore also do so at smaller plants operated by SMEs who are undertaking the same thermoplastics processes albeit on a smaller scale. vi 1 INTRODUCTION This work was carried out in support of HSE s FIT3 Disease Reduction Programme Cancer Project s aim to develop a strategy to reduce the incidence of occupational cancer in Great Britain.