title: The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms.
abstract: In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife.
authors.affiliation: Wageningen University and Research, Department Wageningen Marine Research, Ankerpark 27, 1781 AG, Den Helder, The Netherlands. Electronic address: susanne.kuehn@wur.nl.
authors.forename: Susanne
authors.initials: S
authors.lastname: Kühn
authors.affiliation: Wageningen University and Research, Department Wageningen Marine Research, Ankerpark 27, 1781 AG, Den Helder, The Netherlands; University of Utrecht, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands.
authors.forename: Bernike
authors.initials: B
authors.lastname: van Werven
authors.affiliation: CARAT GmbH, Harderhook 22, 46395 Bocholt, Germany.
authors.forename: Albert
authors.initials: A
authors.lastname: van Oyen
authors.affiliation: Wageningen University and Research, Department Wageningen Marine Research, Ankerpark 27, 1781 AG, Den Helder, The Netherlands.
authors.forename: André
authors.initials: A
authors.lastname: Meijboom
authors.affiliation: Wageningen University and Research, Department Wageningen Marine Research, Ankerpark 27, 1781 AG, Den Helder, The Netherlands; Elisa Bravo - Ecological and Biological Research, Zwaluwlaan 17, 3722 CH Bilthoven, The Netherlands.
authors.forename: Elisa L
authors.initials: EL
authors.lastname: Bravo Rebolledo
authors.affiliation: Wageningen University and Research, Department Wageningen Marine Research, Ankerpark 27, 1781 AG, Den Helder, The Netherlands.
authors.forename: Jan A
authors.initials: JA
authors.lastname: van Franeker
mesh_terms: D059001:Aquatic Organisms / Q000378:metabolism*; D004435:Eating; D004784:Environmental Monitoring; D006878:Hydroxides / Q000737:chemistry*; D010969:Plastics / Q000302:isolation & purification*; D017680:Potassium Compounds / Q000737:chemistry*; D014866:Waste Products; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D006878:Hydroxides; D010969:Plastics; D017680:Potassium Compounds; D014866:Waste Products; D014874:Water Pollutants, Chemical; C029943:potassium hydroxide
keywords: Extraction method; Marine debris; Plastic; Potassium hydroxide (KOH)