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140. Sulphuric, Hydrochloric, Nitric and Phosphoric Acids

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nr 2009;43(7) The Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals 140. Sulphuric, hydrochloric, nitric and phosphoric acids Marianne van der Hagen Jill Järnberg arbete och hälsa | vetenskaplig skriftserie isbn 978-91-85971-14-5 issn 0346-7821 Arbete och Hälsa Arbete och Hälsa (Work and Health) is a scientific report series published by Occupational and Enviromental Medicine at Sahlgrenska Academy, University of Gothenburg. The series publishes scientific original work, review articles, criteria documents and dissertations. All articles are peer-reviewed. Arbete och Hälsa has a broad target group and welcomes articles in different areas. Instructions and templates for manuscript editing are available at http://www.amm.se/aoh Summaries in Swedish and English as well as the complete original texts from 1997 are also available online. Arbete och Hälsa Editorial Board: Editor-in-chief: Kjell Torén Tor Aasen, Bergen Kristina Alexanderson, Stockholm Co-editors: Maria Albin, Ewa Wigaeus Berit Bakke, Oslo Tornqvist, Marianne Törner, Wijnand Lars Barregård, Göteborg Eduard, Lotta Dellve och Roger Persson Jens Peter Bonde, Köpenhamn Managing editor: Cina Holmer Jörgen Eklund, Linköping Mats Eklöf, Göteborg © University of Gothenburg & authors 2009 Mats Hagberg, Göteborg Kari Heldal, Oslo Arbete och Hälsa, University of Gothenburg Kristina Jakobsson, Lund SE 405 30 Gothenburg, Sweden Malin Josephson, Uppsala Bengt Järvholm, Umeå ISBN 978-91-85971-14-5 Anette Kærgaard, Herning ISSN 0346–7821 Ann Kryger, Köpenhamn http://www.amm.se/aoh Carola Lidén, Stockholm Printed at Reproservice, Chalmers Svend Erik Mathiassen, Gävle Gunnar D. Nielsen, Köpenhamn Catarina Nordander, Lund Gunnar Ahlborg, Göteborg Torben Sigsgaard, Århus Staffan Skerfving, Lund Kristin Svendsen, Trondheim Gerd Sällsten, Göteborg Allan Toomingas, Stockholm Ewa Wikström, Göteborg Eva Vingård, Uppsala Preface The main task of the Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals (NEG) is to produce criteria documents to be used by the regulatory authorities as the scientific basis for setting occupational exposure limits for chemical substances. For each document, NEG appoints one or several authors. An evaluation is made of all relevant published, peer-reviewed original literature found. The document aims at establishing dose-response/dose-effect relationships and defining a critical effect. No numerical values for occupational exposure limits are proposed. Whereas NEG adopts the documents by consensus procedures, thereby granting the quality and conclusions, the authors are responsible for the factual content of the document. The evaluation of the literature and the drafting of this document were made by Cand. Scient Marianne van der Hagen at the Norwegian Pollution Control Authority, and Dr. Jill Järnberg at the Swedish Work Environment Authority. The draft document was discussed within the group and the final version was accepted by NEG on April 1, 2008 as its document. The following individuals participated in the elaboration of the document: Gunnar Johanson Institute of Environmental Medicine, Karolinska Institutet, Sweden (chairman) Maria Albin Department of Occupational and Environmental Medicine, University Hospital, Lund, Sweden (former NEG expert) Karin Sørig Hougaard National Research Centre for the Working Environment, Denmark (former NEG expert) Kristina Kjærheim Cancer Registry of Norway (NEG expert) Tiina Santonen Finnish Institute of Occupational Health, Finland (NEG expert) Vidar Skaug National Institute of Occupational Health, Norway (NEG expert) Jill Järnberg and Swedish Work Environment Authority, Sweden (NEG secretariat) Anna-Karin Alexandrie Editorial work and technical editing were performed by the NEG secretariat. This work was financially supported by the former Swedish National Institute for Working Life, The Swedish Work Environment Authority, the Norwegian Ministry of Labour and Social Inclusion and the Nordic Council of Ministers. All criteria document produced by NEG may be downloaded from www.nordicexpertgroup.org . Gunnar Johanson, Chairman of NEG Contents Preface Abbreviations and acronyms 1. Introduction 1 2. Substance identification 1 3. Physical and chemical properties 2 4. Occurrence, production and use 4 5. Measurements and analysis of workplace exposure 6 6. Occupational exposure data 8 7. Toxicokinetics 14 7.1 Deposition 14 7.2 Uptake 15 7.3 Distribution 15 7.4 Biotransformation and excretion 15 8. Biological monitoring 15 9. Mechanisms of toxicity 16 10. Effects in animals and in vitro studies 17 10.1 Irritation, corrosion and sensitisation 17 10.2 Effects of single exposure 20 10.3 Effects of short-term exposure (up to 90 days) 32 10.4 Mutagenicity and genotoxicity 39 10.5 Effects of long-term exposure and carcinogenicity 39 10.6 Reproductive and developmental effects 47 11. Observations in man 47 11.1 Irritation, corrosion and sensitisation 47 11.2 Case reports 48 11.3 Effects of single and short-term exposure 50 11.4 Effects of long-term exposure 63 11.5 Genotoxic effects 66 11.6 Carcinogenic effects 70 11.7 Reproductive and developmental effects 72 12. Dose-effect and dose-response relationships 81 12.1 Sulphuric acid 81 12.1.1 Single/short-term exposure 81 12.1.2 Long-term exposure 83 12.2 Hydrochloric acid 89 12.2.1 Single/short-term exposure 89 12.2.2 Long-term exposure 90 12.3 Nitric acid 91 12.3.1 Single/short-term exposure 91 12.3.2 Long-term exposure 93 12.4 Phosphoric acid 93 13. Previous evaluations by national and international bodies 93 13.1 Sulphuric acid 93 13.2 Hydrochloric acid 95 13.3 Nitric acid 95 13.4 Phosphoric acid 96 14. Evaluation of human health risks 96 14.1 Assessment of health risks 96 14.2 Groups at extra risk 100 14.3 Scientific basis for an occupational exposure limit 100 15. Research needs 102 16. Summary 103 17. Summary in Norwegian 104 18. References 105 19. Data bases used in the literature search 118 Appendix 1. Occupational exposure limits 119 Appendix 2. Previous NEG criteria documents 120 Abbreviations and acronyms ACGIH American Conference of Governmental Industrial Hygienists ARDS acute (or adult) respiratory distress syndrome ATSDR Agency for Toxic Substances and Disease Registry CI confidence interval DECOS Dutch Expert Committee on Occupational Safety DFG Deutsche Forschungsgemeinschaft (German Research Foundation) FEF x forced expiratory flow at x % of FVC FEV 1 forced expiratory volume in one second FVC forced vital capacity IARC International Agency for Research on Cancer IOM Institute of Occupational Medicine, Edinburgh, United Kingdom IPCS International Programme on Chemical Safety LC 50 lethal concentration for 50 % of the exposed animals at single exposure LOAEL lowest observed adverse effect level MD median diameter MMAD mass median aerodynamic diameter MMD mass median diameter NEG Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals NIOSH National Institute for Occupational Safety and Health (United States) NOAEL no observed adverse effect level OR odds ratio PM x particulate matter with aerodynamic diameter up to x µm RADS reactive airways dysfunction syndrome RD 50 air concentration associated with a 50 % decrease in the respiratory rate of animals RR relative risk (risk ratio) SCOEL Scientific Committee on Occupational Exposure Limits (European Union) SG aw specific airway conductance SIR standardised incidence ratio SMR standard mortality ratio STEL short-term exposure limit TNF α tumour necrosis factor alpha TWA time-weighted average VMD volume median diameter WHO World Health Organization 1. Introduction Inorganic acids are of prime importance in the chemical and metal industries. They are used as raw materials in the manufacture of a wide range of chemicals, as well as in refining, electrolysis and extraction in chemical processes. Inorganic acids are widely used in the pickling processes of electroplating, in vehicle production plants and in steel producing plants. The present document concerns the effects of four inorganic acids: sulphuric acid (H 2SO 4), hydrochloric acid (HCl), nitric acid (HNO 3) and phosphoric acid (H 3PO 4). It does not consider sulphur dioxide, nitrous gases, or phosphorous compounds such as phosphorous pentoxide and red phosphorus, which may be converted to phosphoric acid. A previous NEG document published in 1993 described the effects of aerosols of these four acids (142). The biological effects of H 2SO 4 are relatively well investigated, whereas the documentation concerning the effects of the other three acids, discussed in this document, is limited. Acid concentrations are given in mg/m 3. Data originally reported in units of ppm have been converted to units of mg/m 3 by using the conversion factors given in Table 2. Occasionally, the originally reported ppm values are also given. 2. Substance identification Substance identification data for the inorganic acids dealt with in this document are given in Table 1. Although anhydrous sulphuric and nitric acids can be produced, the chemical names usually refer to aqueous solutions of the compounds. Hydrochloric acid is the aqueous solution of hydrogen chloride gas. In this document, the chemical formula HCl may denote hydrochloric acid as well as hydrogen chloride gas. Table 1. Substance identification data of the inorganic acids (142). Common name CAS No. Synonyms Molecular Molecular formula weight Sulphuric acid 7664-93-9 Battery acid, dipping acid, H2SO 4 98.08 electrolyte acid, fertiliser acid, hydrogen
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