es9b07061_si_001.pdf (1.49 MB)
Microstructure Characterization of Oceanic Polyethylene Debris
journal contribution
posted on 2020-03-20, 16:34 authored by Laura Rowenczyk, Alexandre Dazzi, Ariane Deniset-Besseau, Victoria Beltran, Dominique Goudounèche, Pascal Wong-Wah-Chung, Olivier Boyron, Matthieu George, Pascale Fabre, Clément Roux, Anne Françoise Mingotaud, Alexandra ter HallePlastic
pollution has become a worldwide concern. It was demonstrated
that plastic breaks down to nanoscale particles in the environment,
forming so-called nanoplastics. It is important to understand their
ecological impact, but their structure is not elucidated. In this
original work, we characterize the microstructure of oceanic polyethylene
debris and compare it to the nonweathered objects. Cross sections
are analyzed by several emergent mapping techniques. We highlight
deep modifications of the debris within a layer a few hundred micrometers
thick. The most intense modifications are macromolecule oxidation
and a considerable decrease in the molecular weight. The adsorption
of organic pollutants and trace metals is also confined to this outer
layer. Fragmentation of the oxidized layer of the plastic debris is
the most likely source of nanoplastics. Consequently the nanoplastic
chemical nature differs greatly from plastics.