title: Combined Effects of UV Exposure Duration and Mechanical Abrasion on Microplastic Fragmentation by Polymer Type.
abstract: It is important to understand the fragmentation processes and mechanisms of plastic litter to predict microplastic production in the marine environment. In this study, accelerated weathering experiments were performed in the laboratory, with ultraviolet (UV) exposure for up to 12 months followed by mechanical abrasion (MA) with sand for 2 months. Fragmentation of low-density polyethylene (PE), polypropylene (PP), and expanded polystyrene (EPS) was evaluated under conditions that simulated a beach environment. PE and PP were minimally fragmented by MA without photooxidation by UV (8.7 ± 2.5 and 10.7 ± 0.7 particles/pellet, respectively). The rate of fragmentation by UV exposure duration increased more for PP than PE. A 12-month UV exposure and 2-month MA of PP and PE produced 6084 ± 1061 and 20 ± 8.3 particles/pellet, respectively. EPS pellets were susceptible to MA alone (4220 ± 33 particles/pellet), while the combination of 6 months of UV exposure followed by 2 months of MA produced 12,152 ± 3276 particles/pellet. The number of fragmented polymer particles produced by UV exposure and mechanical abrasion increased with decreasing size in all polymer types. The size-normalized abundance of the fragmented PE, PP, and EPS particles according to particle size after UV exposure and MA was predictable. Up to 76.5% of the initial EPS volume was unaccounted for in the final volume of pellet produced particle fragments, indicating that a large proportion of the particles had fragmented into undetectable submicron particles.
authors.affiliation: Oil and POPs Research Group, Korea Institute of Ocean Science and Technology , Geoje 53201, Republic of Korea.|Department of Marine Environmental Sciences, Korea University of Science and Technology , Daejeon 34113, Republic of Korea.
authors.forename: Young Kyoung
authors.initials: YK
authors.lastname: Song
authors.affiliation: Oil and POPs Research Group, Korea Institute of Ocean Science and Technology , Geoje 53201, Republic of Korea.|Department of Marine Environmental Sciences, Korea University of Science and Technology , Daejeon 34113, Republic of Korea.
authors.forename: Sang Hee
authors.initials: SH
authors.lastname: Hong
authors.affiliation: Oil and POPs Research Group, Korea Institute of Ocean Science and Technology , Geoje 53201, Republic of Korea.|Department of Marine Environmental Sciences, Korea University of Science and Technology , Daejeon 34113, Republic of Korea.
authors.forename: Mi
authors.initials: M
authors.lastname: Jang
authors.affiliation: Oil and POPs Research Group, Korea Institute of Ocean Science and Technology , Geoje 53201, Republic of Korea.
authors.forename: Gi Myung
authors.initials: GM
authors.lastname: Han
authors.affiliation: Department of Marine Environmental Sciences, Korea University of Science and Technology , Daejeon 34113, Republic of Korea.|Library of Marine Samples, Korea University of Science and Technology , Geoje 53201, Republic of Korea.
authors.forename: Seung Won
authors.initials: SW
authors.lastname: Jung
authors.affiliation: Oil and POPs Research Group, Korea Institute of Ocean Science and Technology , Geoje 53201, Republic of Korea.|Department of Marine Environmental Sciences, Korea University of Science and Technology , Daejeon 34113, Republic of Korea.
authors.forename: Won Joon
authors.identifier: 0000-0002-9591-8564
authors.initials: WJ
authors.lastname: Shim
mesh_terms: D010969:Plastics; D020959:Polyethylene; D011108:Polymers; D011137:Polystyrenes; D014874:Water Pollutants, Chemical
chemical_list: D010969:Plastics; D011108:Polymers; D011137:Polystyrenes; D014874:Water Pollutants, Chemical; D020959:Polyethylene