Short-chain Polyfluoroalkyl Substances (PFAS) A literature review of information on human health effects and environmental fate and effect aspects of short-chain PFAS Environmental project No. 1707, 2015 Title: Editing: Short-chain Polyfluoroalkyl Substances (PFAS) Jesper Kjølholt 1 Allan Astrup Jensen 2 Marlies Warming 1 1: COWI A/S 2: NIPSECT Published by: The Danish Environmental Protection Agency Strandgade 29 1401 Copenhagen K Denmark www.mst.dk/english Year: ISBN no. 2015 978-87-93352-15-5 Disclaimer: When the occasion arises, the Danish Environmental Protection Agency will publish reports and papers concerning re- search and development projects within the environmental sector, financed by study grants provided by the Danish Envi- ronmental Protection Agency. It should be noted that such publications do not necessarily reflect the position or opinion of the Danish Environmental Protection Agency. However, publication does indicate that, in the opinion of the Danish Environmental Protection Agency, the content represents an important contribution to the debate surrounding Danish environmental policy. Sources must be acknowledged. 2 Contents Preface ...................................................................................................................... 5 Summary and Conclusion .......................................................................................... 7 Sammendrag og konklusion ..................................................................................... 11 1. Introduction ..................................................................................................... 15 1.1 Background and scope .......................................................................................................... 15 1.2 Objective ................................................................................................................................ 15 2. Chemistry and uses ........................................................................................... 17 2.1 Background about polyfluoroalkylated substances (PFAS) ................................................ 17 2.2 Short-chain alternatives to C8-polyfluoroalkylated substances .........................................18 2.3 Developments in industry ................................................................................................... 20 2.4 Recent uses of short-chain alternatives ............................................................................... 21 2.4.1 Impregnation .......................................................................................................... 21 2.4.2 Fire-fighting foams................................................................................................. 21 2.4.3 Metal plating .......................................................................................................... 21 2.4.4 Oil production ........................................................................................................ 21 2.4.5 Food packaging ...................................................................................................... 21 2.5 Substances included in this study ....................................................................................... 22 3. Human health effects ........................................................................................ 23 3.1 General aspects of toxicokinetics and metabolism ............................................................. 23 3.1.1 Uptake and distribution ........................................................................................ 23 3.1.2 Levels in human blood .......................................................................................... 24 3.1.3 Metabolism/biotransformation ............................................................................ 26 3.1.4 Excretion/elimination from the body .................................................................. 27 3.1.5 Blood serum elimination half-lives ...................................................................... 27 3.1.6 Fetal and lactational transfer ................................................................................ 28 3.2 Toxicological mechanisms ................................................................................................... 28 3.2.1 Peroxisome proliferation ...................................................................................... 28 3.2.2 Effects on cell membranes .................................................................................... 29 3.2.3 Effect on lipids ....................................................................................................... 29 3.2.4 Cytotoxicity ............................................................................................................ 29 3.2.5 Neurotoxicity ......................................................................................................... 30 3.2.6 Endocrine disruption ............................................................................................ 30 3.3 Toxic effects of single PFAS ................................................................................................. 30 3.3.1 Perfluoroalkane sulfonic acids/sulfonates (PFSA) ............................................... 31 3.3.2 Perfluoroalkanoic acids/perfluoroalkanoates, perfluorocarboxylic acid/perfluorocarboxylates (PFCA)...................................................................... 36 3.3.3 Perfluoroalkyl halogenides ................................................................................... 39 3.3.4 Perfluoroalkyl phosphor compounds ................................................................... 39 3.3.5 Fluorotelomers and derivatives ............................................................................ 40 3.4 Occurrence and exposure in relation to humans ................................................................ 45 3.4.1 Occurrence in products ......................................................................................... 45 3.4.2 PFAS in indoor air and workplace air .................................................................. 46 4. Environmental fate and effects .........................................................................49 4.1 Environmental behaviour and fate ..................................................................................... 49 4.1.1 Physico-chemical properties of environmental relevance ................................... 49 4.1.2 Abiotic transformation and degradation .............................................................. 50 4.1.3 Biotransformation and degradation ..................................................................... 50 4.1.4 Bioaccumulation .................................................................................................... 51 4.1.5 Sorption, mobility and distribution ....................................................................... 51 4.1.6 Long-range atmospheric and marine transport .................................................. 52 4.2 Environmental effects .......................................................................................................... 52 4.2.1 Toxicity to aquatic organisms ............................................................................... 53 4.2.2 Toxicity to terrestrial organisms........................................................................... 59 4.3 Environmental fate and effects of single PFAS .................................................................... 61 4.3.1 Perfluoroalkane sulfonic acids/sulfonates (PFSA) ............................................... 61 4.3.2 Perfluoroalkanoic acids/perfluoroalkanoates, perfluorocarboxylic acids and perfluorocarboxylates (PFCA) .............................................................................. 62 4.3.3 Perfluoroalkyl halogenides ................................................................................... 63 4.3.4 Perfluoroalkyl phosphor compounds ................................................................... 63 4.3.5 Fluorotelomers ...................................................................................................... 63 4.4 PBT assessment.................................................................................................................... 64 4.5 Environmental occurrence and exposure ........................................................................... 65 4.5.1 Aquatic environment ............................................................................................ 65 4.5.2 Terrestrial environment ........................................................................................ 70 4.5.3 Biota ........................................................................................................................ 71 4.5.4 Atmospheric environment .................................................................................... 73 5. Summary and conclusions ................................................................................ 75 5.1 Human health effects and exposure .....................................................................................75 5.1.1 Human health effects .............................................................................................75 5.1.2 Exposure of humans ............................................................................................. 76 5.2 Environmental fate and effects ..........................................................................................