Intertwined synergistic abiotic and biotic degradation of polypropylene pellets in marine mesocosms

Copyright © 2023 Elsevier B.V. All rights reserved..

The accumulation of plastic waste in the oceans has caused growing concern for its effects on marine life. The interactions of plastics with environmental factors have been linked to fragmentation to micro- and nanoparticles with different properties and consequences, but the mechanism of fragmentation has not been fully understood yet. In this work, we investigate the combined effect of marine communities and ultraviolet (UV) radiation towards the degradation of virgin and artificially weathered polypropylene (PP) pellets after a long-term incubation period in marine mesocosms. The surface chemical alterations and deterioration of the polymer, in conjunction with the attachment and evolution of marine bacterial communities, the development of biofilm and exopolymeric substances (EPS), as well as the colloidal properties (zeta-potential and hydrodynamic diameter) of the mesocosms were studied. The surface area of both types of pellets decreased over time, despite no concrete weight change being observed. Cell growth, EPS production and colloid particle size were correlated to the loss of area. Therefore, we propose that surface area could be effectively monitored, instead of weight loss, as an alternative indicator of polymer degradation in biodegradation experiments. Changes in the chemical structure of the polymer, in addition to the evolution of the biological factors, implied that a complex degradation process alternated between two phases: an abiotic phase, when UV irradiation contributes to the deterioration of the polymer surface layers and a biotic phase, when marine communities degrade the weathered polymer surface to reveal the underlying layer of virgin polymer. Finally, microscopic particles, produced as a result of the decrease in pellet area, promoted the aggregation of colloidal particles. The role and impacts of these colloidal particles in marine ecosystems are yet as unidentified as that of micro- and nano-sized plastic particles and call for further investigation.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:457

Enthalten in:

Journal of hazardous materials - 457(2023) vom: 05. Sept., Seite 131710

Sprache:

Englisch

Beteiligte Personen:

Karkanorachaki, Katerina [VerfasserIn]
Syranidou, Evdokia [VerfasserIn]
Maravelaki, Pagona-Noni [VerfasserIn]
Kalogerakis, Nicolas [VerfasserIn]

Links:

Volltext

Themen:

ATR-FTIR
Aggregation
Degradation
Journal Article
Marine environment
Microplastics
Nanoplastics
Plastics
Polymers
Polypropylenes
Water Pollutants, Chemical

Anmerkungen:

Date Completed 22.06.2023

Date Revised 22.06.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.jhazmat.2023.131710

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM357786513