Papers

61,005 results
|
Article Tier 2

An Overlooked Entry Pathway of Microplastics into Agricultural Soils from Application of Sludge-Based Fertilizers

Researchers analyzed sludge-based fertilizers applied to agricultural soils and found high microplastic concentrations (hundreds to thousands per kilogram of dry weight) that were transferred to soils after application, identifying this as an important but overlooked pathway for terrestrial microplastic contamination.

2020 Environmental Science & Technology 378 citations
Article Tier 2

Stabilized Sewage Sludge as Fertilizer: Risks Related to the Presence of Microplastics

Researchers analyzed microplastic content in sewage sludge-derived fertilizer collected in June and July, finding an average of ~460 mg of microplastics per 100 g of fertilizer with fragments and fibers predominating — raising concerns about agricultural land contamination from sewage sludge application.

2025 Applied Sciences 2 citations
Article Tier 2

Microplastics in Sludges and Soils: A Comprehensive Review on Distribution, Characteristics, and Effects

This review summarizes research on microplastics in sewage sludge and soil, noting that when contaminated sludge is used as fertilizer, it turns farmland into a major reservoir for microplastic pollution. The accumulated microplastics can alter soil properties, harm soil organisms, and potentially enter crops and groundwater, creating pathways for human exposure through food and drinking water.

2024 ChemEngineering 22 citations
Article Tier 2

Microplastic contamination in sewage sludge: Abundance, characteristics, and impacts on the environment and human health

This review focuses on microplastics found in sewage sludge, which is often spread on agricultural land as fertilizer. The practice introduces microplastics directly into farm soil, where they can be taken up by crops or leach into groundwater. This creates a pathway for microplastics to reach human food and drinking water, raising concerns about the safety of using sewage sludge in agriculture.

2023 Environmental Technology & Innovation 98 citations
Article Tier 2

Fate of microplastics in sewage sludge and in agricultural soils

Researchers reviewed how microplastics accumulate in sewage sludge at wastewater treatment plants and then spread into agricultural soils when that sludge is applied as fertilizer, finding that sludge treatment processes can alter microplastic size and shape but do not eliminate them. The review calls for standardized methods to study how different sludge treatments affect microplastic properties and their downstream risks to soil health.

2023 TrAC Trends in Analytical Chemistry 52 citations
Systematic Review Tier 1

The overlooked pathway: A systematic review on sewage sludge treatment as a critical secondary source of terrestrial micro(nano)plastics

This systematic review examines sewage sludge as an overlooked pathway for microplastics to contaminate land, with concentrations reaching over 1,300 particles per kilogram. When this sludge is applied to farmland as fertilizer, aged and chemically modified microplastics enter agricultural soil, where they may be more toxic than fresh particles and can potentially be taken up by crops.

2025 The Science of The Total Environment
Review Tier 2

Microplastics in Sewage Sludge: A review

This review examines the presence and fate of microplastics in sewage sludge from municipal wastewater treatment plants, a topic that has received less attention than microplastics in the water treatment line. The study highlights that agricultural application of sewage sludge is a primary source of microplastic contamination in soils, and provides a comprehensive overview of detection methods, concentrations, and the environmental implications of sludge-borne microplastics.

2023 Environmental Science and Pollution Research 64 citations
Article Tier 2

Microplastics in Sewage Sludge: A Known but Underrated Pathway in Wastewater Treatment Plants

This review finds that wastewater treatment plants effectively transfer microplastics from effluent into sewage sludge, creating a significant but underrated pathway for MP contamination when sludge is applied to agricultural soils.

2021 Sustainability 46 citations
Article Tier 2

Impact of sewage sludge application on soil microplastic accumulation and nutrient levels: Analysis of 22 years of data from central UK farmland

Researchers analyzed a 22-year dataset from 5,323 fields in central UK to examine the relationship between repeated sewage sludge application and microplastic accumulation in agricultural soils, alongside changes in nutrient levels such as nitrogen and phosphorus. They found that microplastic concentrations increased with cumulative sludge applications while nutrients were taken up by crops, raising concerns about long-term plastic accumulation in farmland receiving sludge-derived fertilizers.

2024 Zenodo (CERN European Organization for Nuclear Research)
Article Tier 2

Sewage Sludge in Farmlands: A Gateway to Soil Microplastic Pollution?

Researchers analysed microplastic contamination in dewatered anaerobically digested sewage sludge and adjacent agricultural fields in the UK with varied sludge application histories, using fluorescence microscopy and FTIR/Raman spectroscopy to detect predominantly polyethylene, polyester, polypropylene, polystyrene, PVC, and polyamide particles.

2024
Article Tier 2

A method for the characterisation of microplastics in sludge

Researchers developed a method for detecting and characterizing microplastics in sewage sludge, which concentrates the majority of microplastics removed during wastewater treatment. This method is important because sludge is widely spread on agricultural land, making it a key pathway for microplastics entering soils.

2019 MethodsX 23 citations
Article Tier 2

Sewage sludge application as a vehicle for microplastics in eastern Spanish agricultural soils

Scientists measured microplastics in sewage sludge from Spanish wastewater treatment plants and in agricultural soils receiving sludge applications, finding that sludge application transferred hundreds to thousands of microplastic particles per kilogram into agricultural soil.

2020 Environmental Pollution 608 citations
Article Tier 2

Microplastics in an agricultural soil following repeated application of three types of sewage sludge: A field study

Researchers investigated microplastics in agricultural soil after repeated sewage sludge application, finding that sludge-amended soils contained significantly more small microplastic particles than unamended soils, with particle accumulation varying by sludge type.

2021 Environmental Pollution 171 citations
Article Tier 2

Tracking nonregulated micropollutants in sewage sludge: Antimicrobials, OH-PAHs, and microplastics — Environmental risks, fertilizer implications and energy considerations

Researchers tracked antimicrobials, hydroxylated polycyclic aromatic hydrocarbons, and microplastics in sewage sludge and fertilizers derived from it. The study found that while fertilizer production reduced some contaminants, significant levels of antimicrobials and an average of over 2,400 microplastic particles persisted in stabilized sludge, raising concerns about environmental contamination when these materials are applied to agricultural land.

2025 Energy Reports 8 citations
Article Tier 2

Mapping microplastics in sludge

Researchers mapped microplastic contamination in sewage sludge from eight Norwegian wastewater treatment plants, finding plastics in all ten samples with an overall average of 6,077 particles per kilogram dry weight. Based on current sludge application rates in Norway, researchers estimated that over 500 billion microplastic particles enter the environment annually through agricultural and land application of sewage sludge.

2018 Duo Research Archive (University of Oslo) 80 citations
Review Tier 2

Occurrence and environmental consequences of microplastics and nanoplastics from agricultural reuse of wastewater and biosolids in the soil ecosystem: A review

This review examines how wastewater and sewage sludge used in agriculture introduce microplastics and nanoplastics into farm soil, where they can persist and accumulate over time. Municipal wastewater can contain thousands of plastic particles per liter, and treated sewage sludge used as fertilizer can contain over 30,000 particles per liter. These practices create a long-term buildup of plastic contamination in agricultural soil that can affect crops, groundwater, and ultimately human food and water supplies.

2025 The Science of The Total Environment 8 citations
Article Tier 2

Co-occurrence of microplastics, heavy metals, and Pseudomonas aeruginosa in sewage sludge: One matrix, multiple threats to agricultural soils

Researchers quantified microplastics, heavy metals, and antibiotic-resistant bacteria in sewage sludge from eight wastewater treatment plants in Hungary. The study found an average of 54 microplastic particles per gram of dried sludge, estimating that approximately 586 billion microplastic particles enter Hungarian agricultural soils annually through sludge application, alongside concerning levels of heavy metals and resistant Pseudomonas aeruginosa strains.

2026 Journal of Hazardous Materials Advances
Article Tier 2

Agricultural application of microplastic-rich sewage sludge leads to further uncontrolled contamination

Researchers found that 44% of microplastics from sewage sludge applied to agricultural land migrated to nearby untreated areas, demonstrating that this common fertilizer practice leads to further uncontrolled contamination of surrounding soils.

2021 The Science of The Total Environment 103 citations
Article Tier 2

Configuration-driven microplastic fate in full-scale sewage sludge treatment and opportunities for system-level mitigation

Researchers examined how different treatment configurations in wastewater plants shape the types and concentrations of microplastics that end up in sewage sludge — the solid byproduct that is frequently spread on agricultural land as fertilizer. Microplastic concentrations in final sludge ranged from 617 to 936 particles per gram of dry solids, with fine fragments under 100 micrometers dominating, and the specific sequence of thickening, digestion, and dewatering steps significantly influenced which polymer types were retained. Since sludge application is a major route for microplastics to enter farmland, optimizing treatment processes could meaningfully reduce environmental contamination.

2026 Journal of Environmental Management
Article Tier 2

Seasonal Variation, Distribution and Characteristics of Microplastic in Sewage Sludge

Researchers investigated seasonal variation in microplastic concentration, distribution, and characteristics within sewage sludge at wastewater treatment plants, examining how precipitation patterns and sludge treatment processes influence microplastic retention and the pathways by which sludge-borne microplastics enter agricultural soils upon land application.

2022 Zenodo (CERN European Organization for Nuclear Research)
Article Tier 2

Microplastics in sewage sludge from the wastewater treatment plants in China

Researchers analyzed microplastics in sewage sludge from wastewater treatment plants across China, finding high concentrations of microplastics — predominantly fibers and fragments — raising concerns about their spread when sludge is applied to agricultural land.

2018 Water Research 1001 citations
Article Tier 2

Evidence of microplastic accumulation in agricultural soils from sewage sludge disposal

Agricultural soils from 31 fields with different sludge application histories were analyzed for microplastics, finding significant accumulation in fields with repeated sludge applications and a positive correlation between application frequency and plastic particle counts. The study provides direct field evidence that sewage sludge fertilization is a major pathway for microplastic accumulation in agricultural soil.

2019 The Science of The Total Environment 1333 citations
Article Tier 2

Extent and impact of microplastics on soil nutrients and biota: a trade-off assessment

This review examines the extent of microplastic inputs from sewage sludge applied to agricultural soils, synthesizing evidence on how sludge-derived microplastics affect soil nutrient availability, soil biota, plant performance, and crop productivity, concluding that the benefits of sludge as a soil amendment must be weighed against its role as a vector for microplastic contamination.

2022 Zenodo (CERN European Organization for Nuclear Research)
Article Tier 2

Assessing emerging and priority micropollutants in sewage sludge: environmental insights and analytical approaches

Researchers reviewed the presence of emerging pollutants, including microplastics, pharmaceuticals, and industrial chemicals, in sewage sludge that is commonly applied to agricultural land. They found that current analytical methods are improving but still face challenges in detecting these contaminants at low concentrations in complex sludge samples. The study highlights the environmental risks of spreading pollutant-laden sludge on farmland and calls for better monitoring standards.

2023 Environmental Science and Pollution Research 19 citations