Occurrence and chemical characteristics of microplastic paint flakes in the North Atlantic Ocean

Non-fibrous microplastics sampled by the Continuous Plankton Recorder (CPR) Survey throughout the North Atlantic Ocean during 2018 have been recorded and a selection (n = 17, or 16.7%) physically and chemically characterised. The average abundance of non-fibrous particles captured by the plankton silks and detectable by microscopy was estimated to be around 0.01 m(-3), with the highest concentrations evident in shelf seas of northwest Europe. Amongst the samples analysed, median size was 180 mu m and, based on visible properties (e.g., brittleness, layering) and infra-red spectra, all but one were identified as flakes of paint. Semi quantitative analysis by energy-dispersive X-ray fluorescence spectrometry with a collimated beam revealed that six flakes from European shelf seas were Cu-based antifouling formulations (without evidence of organoSn compounds), and five with a broader geographical distribution were Pb-based formulations of likely marine origin. Other elements regularly detected included Cr, Fe, Ti and Zn that were present in pigments or as contaminants from the underlying substrate. After fibres, paint flakes appear to be the most abundant type of microplastic in the oceans that, because of the abundance and mobility of metallic additives, deserve closer scientific attention. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

Non-fibrous microplastics sampled in the North Atlantic Ocean in 2018 were characterized physically and chemically, with paint flakes identified as the most common type, found at highest concentrations in the European shelf seas, containing metallic elements like copper and lead.