We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Municipal biosolids and effluent irrigated onto land are significant sources of microplastics to the terrestrial environment in New Zealand
AI summary Read the abstract
Researchers found that the application of municipal biosolids and treated wastewater effluent to agricultural land is a significant source of microplastic contamination in soils. Analysis of biosolids and irrigation water from wastewater treatment plants confirmed that even after treatment, these materials carry substantial microplastic loads onto farm fields. The study highlights a major pathway by which microplastics from household and industrial waste are continuously introduced into agricultural soils.
The application of biosolids and irrigation of municipal effluent from wastewater treatment plants (WWTPs) onto terrestrial soils is often an economically and environmentally preferred method to reclaim beneficial nutrients and water in order to prevent landfilling or discharge of biowaste into sensitive environments, along with reliance on synthetic fertilisers and extraction of freshwater for irrigation. Previous literature has identified WWTPs as a major source of microplastics to the environment. WWTPs are not designed to remove microplastics from sewage, and microplastics are retained in sewage sludge or released with effluent. There is a lack of knowledge of the amount and types of microplastics in municipal biowaste entering the terrestrial environment in New Zealand. This is the first study to have characterised microplastics present in biosolids and soil irrigated with effluent in New Zealand. Biosolids were collected from five WWTPs, along with soil samples from five sites irrigated with municipal effluent. A soil sample from a reference site which had not been irrigated with effluent was collected for comparison. All samples underwent a chemical digest by a wet peroxide oxidation followed by density separations. All suspected microplastic particles were analysed by micro-Fourier transform infrared spectroscopy (µ-FTIR). Microplastics were present in biosolids in the highest amounts, with average concentrations ranging from 0.92 – 4.96 particles/g (dry weight). In soil irrigated with effluent, microplastics ranged from 0.02 – 0.76 particles/g (dry weight). Fragments were the most common morphotype found across both sample types, with polypropylene, polyethylene and acrylic the most frequently detected polymer types. Common morphotypes detected across samples include glitter and cleaning sponge fragments, suggesting the need for greater regulation of unnecessary plastic products. Also see: https://micro2022.sciencesconf.org/426975/document
More Papers Like This
Quantification of microplastics in biowastes including biosolids, compost, and vermicompost destined for land application
AI summary Read the abstract
Researchers measured microplastic concentrations in biosolids, compost, and vermicompost destined for land application in New Zealand, finding contamination across all biowaste types. The study highlights how spreading these materials on farmland introduces microplastics into soil, where they could persist and potentially enter the food chain through crop uptake.
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.
Investigation and analysis of microplastics in sewage sludge and biosolids: A case study from one wastewater treatment works in the UK (article)
AI summary Read the abstract
This UK case study tracked microplastics through an entire sewage sludge treatment stream at one wastewater works, from raw influent through to biosolids applied to agricultural land. Microplastics were present at every stage and concentrated in biosolids, suggesting land application of biosolids is a significant pathway for introducing microplastics into agricultural soils.
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.
Variation in microplastic concentration, characteristics and distribution in sewage sludge & biosolids around the world
AI summary Read the abstract
Researchers systematically reviewed 65 studies on microplastics in sewage sludge and biosolids from wastewater treatment plants around the world. They found that while treatment processes remove 57% to 99% of microplastics from wastewater, the removed particles concentrate in sludge that is often applied to agricultural land. The review highlights that land application of biosolids may be a significant, underappreciated pathway for microplastic pollution in soils.
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.