0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Gut & Microbiome Human Health Effects Sign in to save

Fate and Impacts of Microplastics in Sludge Anaerobic Digestion: Effects on Methanogenic and Acidogenic Pathways

ChemistrySelect 2025 Score: 48 ? 0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Hongzhi Ma, Tao Yu, Weihong Chen, Baochuan Qi, Dan Feng, Dayi Qian, Jian Yang

Summary

This review examined how microplastics in sewage sludge influence anaerobic digestion performance, covering effects on methane production, volatile fatty acid accumulation, and microbial community function. MPs inhibited methanogenesis at higher concentrations by altering microbial community structure and disrupting electron transfer pathways in the anaerobic digestion process.

Abstract Microplastics (MPs) in sludge and their impact on anaerobic digestion (AD) have become a critical environmental concern. This review examines the mechanisms by which MPs influence sludge AD, particularly methane and volatile fatty acid (VFA) production. First, we discuss the occurrence, sources, and physicochemical properties (e.g., size, shape, surface characteristics) of MPs in sludge, which govern their behavior. Next, we explore how MPs disrupt AD, potentially suppressing methane generation through physical obstruction, chemical toxicity, and biological interference. MPs also alter VFA composition and metabolic pathways, notably regulating short‐chain fatty acids like acetate and propionate. Furthermore, MPs may synergize with co‐pollutants (e.g., heavy metals, organic contaminants), amplifying environmental risks. These findings underscore the need for deeper mechanistic insights to assess ecological impacts and optimize sludge valorization strategies.

Sign in to start a discussion.

More Papers Like This

Article Tier 2

Occurrence, effect, and fate of residual microplastics in anaerobic digestion of waste activated sludge: A state-of-the-art review

This review assessed the occurrence, behavior, and fate of microplastics in anaerobic digestion of waste activated sludge, finding that MPs survive digestion largely intact but can affect methane production and microbial community composition, and that digestate land application remains a major pathway for releasing sludge-retained MPs to soil.

Article Tier 2

Effects of Micro(nano)plastics on Anaerobic Digestion and Their Influencing Mechanisms

This review examines how micro- and nanoplastics from organic waste streams affect anaerobic digestion (AD) performance, covering impacts on methane production, microbial community structure, and enzyme activity. It identifies plastic polymer type and concentration as key variables determining whether MPs stimulate or inhibit digestion processes.

Article Tier 2

Systematic study of microplastics on methane production in anaerobic digestion: Performance and microbial response

Microplastics are increasingly found in wastewater treatment systems, and this study systematically examined how different types, concentrations, and sizes of microplastics affect the anaerobic digestion process used to break down sewage sludge and generate biogas. Polyethylene microplastics were found to inhibit methane production, with finer particles and higher concentrations causing greater disruption to the microbial communities driving digestion. The findings matter because microplastics in sewage sludge can impair the treatment process and also end up spread on agricultural land when sludge is used as fertilizer.

Article Tier 2

A review of mechanisms underlying the impacts of (nano)microplastics on anaerobic digestion

This review summarized mechanisms by which nano- and microplastics affect anaerobic digestion in wastewater treatment, covering inhibition and enhancement pathways, impacts on biogas production and methane yield, and effects on microbial community structure.

Article Tier 2

Revealing the Mechanisms of Polyethylene Microplastics Affecting Anaerobic Digestion of Waste Activated Sludge

Researchers studied how polyethylene microplastics affect the anaerobic digestion of sewage sludge, a common wastewater treatment process. They found that higher concentrations of microplastics significantly reduced methane production by disrupting microbial communities and enzyme activities essential for digestion. The study reveals that microplastic contamination in wastewater systems can undermine the efficiency of sludge treatment and biogas generation.

Share this paper