Microplastics in Msw-Derived Compost: Release Rate, Characteristics, Ecological Risks, and Mitigation Strategies for Sustainable Agriculture Publisher



M Panahi Fard MASOUD ; Ah Mahvi Amir HOSSEIN ; S Jorfi SAHAND ; A Takdastan AFSHIN ; H Schoenberger HARALD ; A Azari ALI ; Na Jaafarzadeh Haghighifard Neamatollah ALLAH
Source: Environmental Pollutants and Bioavailability Published:2025

Abstract

Plastic contamination in compostable organic fractions of municipal solid waste (MSW) is a key route for microplastics (MPs) entering agricultural soils. This study investigated MP concentrations and characteristics in raw MSW organics and composts from both industrial and laboratory processes. MPs were identified using stereo microscopy, SEM, and Micro-Raman spectroscopy. Concentrations reached 63.75 ± 22.1, 253.3 ± 38.7, and 173.3 ± 30.2 items/kgdw in raw MSW, industrial, and lab-scale composts, respectively. Fragments and fibers dominated, with over 50% sized between 500–5000 µm. Transparent MPs were most common in industrial compost; green and red ones prevailed in raw MSW and lab composts. Polyamide (PA) and polypropylene (PP) were the most frequent polymers. Pollution Load Index (PLI) values indicated low to moderate pollution levels. The Polymer Hazard Index (PHI) showed high hazard in industrial compost and low to medium in other samples. Source separation of MSW significantly reduced MPs in compost, underscoring its importance in waste management strategies. © 2025 Elsevier B.V., All rights reserved.