Microplastics in composting of rural domestic waste: abundance, characteristics, and release from the surface of macroplastics. (1st April 2021)

• Record Type: Journal Article
• Authors: Gui, Jiaxi; Sun, Yue; Wang, Jingli; Chen, Xu; Zhang, Shuchi; Wu, Donglei
• Is Part Of: Environmental pollution. Volume 274(2021)
• Publication Date: 2021-04-01
• Subjects: Microplastics -- Aerobic composting -- Rural domestic waste -- Composting product -- Treatment process -- Macroplastics weathering; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2021.116553
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: The rural domestic waste (RDW) compost has been widely used in agriculture and horticulture, but little is known about microplastics (MPs) in RDW composting. The current work deals with the abundance and characteristics of MPs in RDW composting, and the effects of composting processes on the composition of MPs. Compost samples from two RDW treatment stations were investigated, and a lab-scale experiment was carried out to verify the possible release of MPs from macroplastics (>25 mm) contained in the RDW during composting. MPs were identified using stereo-microscope and μ-FTIR. The average abundance of MPs (0.05–5 mm) in the RDW compost products was 2400 ± 358 items/kg (dry weight), and the main MPs shapes were fibers and films. Polyester, polypropylene (PP) and polyethylene (PE) were the most common polymer types. MPs having a size <1 mm accounted for more than 50% of the total quantity. With the progress of composting, the proportion of MPs having size <1 mm increased, and more foam MPs were observed in the late stage of composting. Under the influence of mechanical force, oxidation and biodegradation, a piece of expanded polystyrene (EPS), PP and PE macroplastic could release 4–63 MPs particles during the composting. Thus, the RDW compost was a significant source of MPs in soils, and the MPs in compost products were closely related to the quantity and type of plastic waste present in RDW, which helped to suggest better MPs control strategies. Graphical abstract: Image 1 Highlights: The compost of rural domestic waste (RDW) was a source of soil microplastics (MPs). The average abundance of MPs in the compost product of RDW was 2400 ± 358 n/kgdw . The abundance and composition of MPs were different before and after composting. Macroplastics (>25 mm) contained in RDW released MPs during composting. Abstract : The compost from rural domestic waste was the source of soil MPs, and the abundance and characteristics of MPs changed during the composting process.