Quantification and characterization of microplastics in surface water samples from the Northeast Atlantic Ocean using laser direct infrared imaging

Jeannette Hansen; Lars Hildebrandt; Tristan Zimmermann; Fadi El Gareb; Elke Kerstin Fischer; Daniel Pröfrock

doi:10.1016/j.marpolbul.2023.114880

Quantification and characterization of microplastics in surface water samples from the Northeast Atlantic Ocean using laser direct infrared imaging

Mar Pollut Bull. 2023 May:190:114880. doi: 10.1016/j.marpolbul.2023.114880. Epub 2023 Apr 7.

Authors

Jeannette Hansen¹, Lars Hildebrandt², Tristan Zimmermann², Fadi El Gareb³, Elke Kerstin Fischer⁴, Daniel Pröfrock⁵

Affiliations

¹ Department for Inorganic Environmental Chemistry, Helmholtz-Zentrum Hereon, Max-Planck-Straße 1, 21502 Geesthacht, Germany; Center for Earth System Research and Sustainability, Universität Hamburg, Bundesstraße 55, 20146 Hamburg, Germany.
² Department for Inorganic Environmental Chemistry, Helmholtz-Zentrum Hereon, Max-Planck-Straße 1, 21502 Geesthacht, Germany.
³ Department for Inorganic Environmental Chemistry, Helmholtz-Zentrum Hereon, Max-Planck-Straße 1, 21502 Geesthacht, Germany; Department of Earth System Sciences, Institute for Geology, Universität Hamburg, Bundesstraße 55, 20146 Hamburg, Germany.
⁴ Center for Earth System Research and Sustainability, Universität Hamburg, Bundesstraße 55, 20146 Hamburg, Germany.
⁵ Department for Inorganic Environmental Chemistry, Helmholtz-Zentrum Hereon, Max-Planck-Straße 1, 21502 Geesthacht, Germany. Electronic address: daniel.proefrock@hereon.de.

PMID: 37031558
DOI: 10.1016/j.marpolbul.2023.114880

Abstract

15 filtration samples were collected at eight locations onboard the RV Sonne (cruise SO279 in 2020) from 6 m water depth using a fractionated stainless-steel filtration unit. The size fraction > 300 μm was visually examined and potential microplastic particles were analyzed by ATR-FTIR spectroscopy. The treatment of size class 20 μm < d < 300 μm was based on enzymatic-oxidative microwave-assisted "one-pot" matrix digestion in conjunction with analysis of the microplastics by time-efficient LDIR imaging. Total number concentrations ranged from 47 to 2154 microplastic particles per m³ (average for all stations: 500 ± 700 microplastic particles m^-3 (1 SD; n = 8)). In total, 20 polymer types were identified. The most common polymer types were polyethylene terephthalate (20 %) and acrylates/polyurethane/varnish (15 %). 93 % of the detected microplastics were smaller than 100 μm in length. Analysis of sample replicates indicates high spatio-temporal variations in microplastic pollution within the investigated region.

Keywords: Anthropogenic particles; Fractionated filtration; LDIR; Marine environment; Pollution; QCL imaging.

MeSH terms

Atlantic Ocean
Environmental Monitoring / methods
Microplastics* / analysis
Plastics / analysis
Polymers
Water / analysis
Water Pollutants, Chemical* / analysis

Substances

Microplastics
Plastics
Water Pollutants, Chemical
Polymers
Water