0
Article Tier 2 Detection Methods Environmental Sources Food & Water Human Health Effects Policy & Risk Sign in to save

Transport and Accumulation of Microplastics from Biosolids to Australian Agricultural Soils: Detection of Microplastics Down to 1 μm

Environmental Science & Technology 2024 9 citations

AI summary Read the abstract

Researchers tracked how microplastics transfer from biosolids, a common organic fertilizer derived from sewage treatment, into Australian agricultural soils. Using advanced detection methods capable of identifying particles as small as 1 micrometer, they found significant microplastic accumulation in fields where biosolids had been applied. The findings highlight a largely unregulated pathway through which microplastics enter the food production chain.

Polymers
Body Systems

The shift toward sustainable agriculture involves replacing inorganic fertilizers with organic alternatives like biosolids. However, concerns arise over emerging contaminants, such as microplastics (MPs), which remain largely unregulated. Despite their common use in Australia, the transfer of MPs from biosolids to agricultural soils remains largely unknown. Herein, we have investigated the abundance, characteristics, and transport of MPs resulting from biosolids application in two Queensland agricultural sites. MP concentrations were significantly higher in biosolid-amended soils (average of 1137 MPs/kg) than in reference sites (average of 36 MPs/kg), correlating with the volume, time since application, and frequency of biosolids application. MPs > 25 μm were predominantly polyethylene, polypropylene, and poly(methyl methacrylate) fragments (up to 85%). Fibers constitute only 15-30% of MPs and mainly in larger sizes (average 1011 μm), whereas fragments (average 188 μm) and beads (average 72 μm) had smaller size ranges. Despite analytical challenges using Raman spectroscopy, detected smaller MPs (1-25 μm) were fragments composed of polyethylene, polypropylene, and poly(vinyl alcohol). This study provides the first report of MPs down to 1 μm in Australian agricultural soils. Our findings suggest a need to assess the long-term impact of MPs in biosolids on soil health and food safety. We call on policymakers to consider the implementation of effective MP source control strategies and the development of guidelines for acceptable biosolids application rates.

More Papers Like This

Article Tier 2

Identification of microplastics extracted from field soils amended with municipal biosolids

AI summary Read the abstract

Researchers developed a method for extracting and identifying microplastics from agricultural soils that had been treated with municipal biosolids, a common fertilizer derived from wastewater treatment. They found a variety of plastic polymer types in the soil, confirming that biosolid application is a pathway for microplastic contamination of farmland. The study provides a reliable technique for tracking how microplastics cycle through agricultural environments.

Article Tier 2

Biosolid amendments as drivers for microplastic pollution in soil: Measurements and insight from multiple analytical methods in an agricultural field study

AI summary Read the abstract

Scientists analyzed farm soil that had been treated with sewage sludge (a common fertilizer made from treated wastewater) years earlier, comparing it to untreated soil to identify tiny plastic particles left behind. This research provides detailed tools and data for detecting these microplastics, helping build the scientific groundwork needed to understand how farm fertilizing practices may contribute to plastic pollution in the food we grow.

Article Tier 2

Biosolid amendments as drivers for microplastic pollution in soil: Measurements and insight from multiple analytical methods in an agricultural field study

AI summary Read the abstract

Farms sometimes spread "biosolids" (treated sewage sludge) on fields as fertilizer, and this study measured microplastic particles in soil that had received these applications over a decade compared to untreated farmland. Using detailed chemical testing, researchers confirmed that soil treated with sludge contained identifiable plastic contamination, supporting concerns that this common farming practice can be a source of microplastics building up in agricultural land. Since these plastics can end up in the crops we eat and potentially in our food and water supply, understanding where they come from is an important step toward reducing our overall exposure.

Article Tier 2

Investigation and analysis of microplastics in sewage sludge and biosolids: A case study from one wastewater treatment works in the UK

AI summary Read the abstract

Researchers investigated microplastic contamination in sewage sludge and biosolids at a UK wastewater treatment plant and found significant quantities of microplastics persisting through the treatment process. Since millions of tonnes of biosolids are applied to farmland annually in the UK, this represents a major pathway for microplastic pollution entering agricultural soils. The study highlights the need for better monitoring and treatment methods to reduce microplastic transfer from wastewater to the terrestrial environment.

Article Tier 2

From wastewater treatment plants to farmland: Microplastic quantification, transfer, and risk assessment from biosolids use in Tasmania, Australia

AI summary Read the abstract

Researchers quantified microplastics in wastewater and biosolids from Tasmanian treatment plants, detecting 127 to 138 particles per gram in biosolids, with polyethylene as the most abundant polymer. The study estimates that billions of microplastic particles are transferred annually to agricultural soils through biosolids reuse, and a preliminary risk assessment suggests these levels may pose ecological concerns.

Research digests by email

When a large batch of papers lands in the Atlas, we read through it and send a short write-up of what stood out.

Email me about

Share this paper