Long-term aging and degradation of microplastic particles: Comparing in situ oceanic and experimental weathering patterns.
Mar Pollut Bull
; 110(1): 299-308, 2016 Sep 15.
Article
em En
| MEDLINE
| ID: mdl-27344287
ABSTRACT
Polypropylene, low-density polyethylene, and high-density polyethylene pre-production plastic pellets were weathered for three years in three experimental treatments dry/sunlight, seawater/sunlight, and seawater/darkness. Changes in chemical bond structures (hydroxyl, carbonyl groups and carbon-oxygen) with weathering were measured via Fourier Transform Infrared (FTIR) spectroscopy. These indices from experimentally weathered particles were compared to microplastic particles collected from oceanic surface waters in the California Current, the North Pacific Subtropical Gyre, and the transition region between the two, in order to estimate the exposure time of the oceanic plastics. Although chemical bonds exhibited some nonlinear changes with environmental exposure, they can potentially approximate the weathering time of some plastics, especially high-density polyethylene. The majority of the North Pacific Subtropical Gyre polyethylene particles we measured have inferred exposure times>18months, with some >30months. Inferred particle weathering times are consistent with ocean circulation models suggesting a long residence time in the open ocean.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Plásticos
/
Poluentes Químicos da Água
País/Região como assunto:
America do norte
Idioma:
En
Revista:
Mar Pollut Bull
Ano de publicação:
2016
Tipo de documento:
Article