Plasticrusts and pyroplastic: two novel plastic debris types detected in Giglio island, Italy Julius A. Ellrich1 & Sonja M. Ehlers2,3 1Julius_Ellrich@web.de; Independent Researcher, Sankt-Josef-Straße 25, 56068 Koblenz, Germany 2Ehlers@bafg.de; Department of Animal Ecology, Federal Institute of Hydrology, Am Mainzer Tor 1, 56068 Koblenz, Germany 3Institute for Integrated Natural Sciences, University of Koblenz-Landau, 56070 Koblenz, Germany www.juliusaellrich.weebly.com, www.sonjamehlers.weebly.com REFERENCES: Ehlers SM & Ellrich JA 2020. First record of plasticrusts and pyroplastic from the Mediteranean Sea. Marine Pollution Bulletin 151: 110845. Doi: 10.1016/jmarpolbul. 2019.110845 INTRODUCTION: Fig.1A)LocationofGiglioislandintheTyrrhenianSea.B)Locationsofthefivesurveyed habitats (H1-H5) in Giglio. H2 and H3 were adjacent habitats and, thus, depicted by a singledot.C)Thewave-exposedrockyshore(H1).D)Thewave-shelteredbeach(H2). METHODS: Inthefield,wemeasuredplasticrustdensity,areaandpercentcoverusing quadrats(10 cm x 10 cm). At the lab, we determined plasticrust thickness using a digital microscope and pyroplastic size using digital calipers. Furthermore, we identified the plasticrust and pyroplastic materials (i.e., polymer types) with Fourier-transform infrared spectroscopy (FTIR, Fig. 2). We conducted our FTIR measurements in attenuated total reflectance (ATR) mode in a wavenumber range between 4000 and 370 cm−1with 8 co- added scans and a spectral resolution of 4 cm−1. Then, we compared the obtained spectrawiththeBrukerspectrallibraryinOpus7.5software. Plasticrusts and pyroplastic are novel plastic debris types that have only recently been reported for the first time from Madeira island (Atlantic Ocean, Gestoso et al. 2019) and the southern United Kingdom, respectively (Turner et al. 2019). While plasticrusts result from plastic debris being wave-swept across rugose rocks, pyroplastics derive from burnt plastic waste. During field surveys in Giglio island (Tyrrhenian Sea, Italy), we detected plasticrusts on a wave-exposed rocky shore and pyroplasticonawave-shelteredsandybeach(Ehlers&Ellrich2020,Fig.1). Fig. 2 Sonja M. Ehlers identifying polymer types using FTIR (Vertex 70, Bruker, Ettlingen, Germany) at the Federal Institute of Hydrology in Koblenz, Germany. C D Plasticrust (Fig. 3A) density was 3.25 ± 1.65 plasticrusts/dm2 (mean ± SE; n= 4 quadrats). Plasticrust area was 0.46 ± 0.08 mm2 (n= 13 plasticrusts). Plasticrust cover was 0.02 ± 0.01 % (n= 4 quadrats). Plasticrust thickness ranged between 0.5 and 0.7 mm. FTIR analyses revealed the plasticrust material as polyethylene (PE, Fig. 3B). We didnotdetectanyplasticrustsonthewave-shelteredrockyshores(H3-H5,Fig.1B). ACKNOWLEDGEMENTS: We thank Professor Dr Jochen H. E. Koop for letting us use the FTIR spectrometer at the Federal Institute of Hydrology in Koblenz, Germany. RESULTS: Fig. 3 A) The detected blue plasticrusts consisted of (B) PE material. Fig. 4 A) The detected pyroplastic with blue inclusions. B) Pyroplastic close-up. C) The FTIR spectrum that revealed PET as the pyroplastic material. D) PET bottle found on the beach (H2, Fig. 1B). E) The FTIR spectrum that confirmed PET as the bottle material. The pyroplastic had a stone-like appearance (Fig. 4A) with blue inclusions (Fig. 4B). Pyroplastic size was approximately 2 cm × 1.4 cm × 0.5 cm (length x width x height). FTIR analyses showed that the pyroplastic material was polyethylene terephthalate (PET, Fig. 4C). On the beach, we detected burnt charcoal near the pyroplastic. Finally, wefoundseveralPETbeveragebottles(Fig.4D, E)ineachhabitat(H1-H5,Fig.1B). DISCUSSION: A B Absorbance units Wavenumber (cm-1) FTIR measurement spectrum Bruker library spectrum A B D E Wavenumber (cm-1) C Absorbance units Absorbance units Wavenumber (cm-1) FTIR measurement spectrum Bruker library spectrum FTIR measurement spectrum Bruker library spectrum Our results from Giglio resemble findings from Madeira and the United Kingdom indicating