We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
The changes of microplastics’ behavior in adsorption and anaerobic digestion of waste activated sludge induced by hydrothermal pretreatment
AI summary Read the abstract
This study measured microplastic concentrations in the guts of juvenile Atlantic cod and haddock in the Gulf of Maine, finding particles in over 60% of individuals examined. Fibers were most common and the authors linked sources to fishing activity and coastal urbanization.
Waste activated sludge (WAS) contains high concentrations of microplastics (MPs), which could serve as vectors of various organic pollutants and heavy metals, causing synergistic transportation and pollution. The application of combined hydrothermal pretreatment (HTP) and anaerobic digestion (AD) has raised growing concerns since the low-temperature hydrothermal treatment could enhance the biogas production of WAS. However, the changes in physicochemical properties, adsorption performances, and effects on AD of MPs by HTP have not been studied. The study used three typical MPs in WAS, and it was found that the HTP (170°C & 30min) increased MPs' specific surface area and carbonyl index (CI) while decreasing the relative crystallinity. The adsorption capacity to Cd increased through the carbonylation for polyethylene microplastic (PE-MP) and polystyrene microplastic (PS-MP) while decreasing by the dechlorination for polyvinyl chloride microplastic (PVC-MP). Meanwhile, increased hydrophilicity reduced the adsorption capacities of all three typical MPs for ofloxacin. The above results indicated that the HTP could be worth blocking the adsorption of polar MPs for polar pollutants. For the pristine MPs, only PVC-MP at the highest concentration (0.5 g kg VS) significantly (p < 0.05) reduced methane production by 16.2 ± 3.3% of WAS without the HTP. However, the HTP resulted in significant (p < 0.05) inhibition of methane production of WAS at high concentrations of PE-MP and PVC-MP (e.g., 0.1 and 0.5 g kg VS), which was due to the acceleration of the released toxic plastic additives (dibutyl phthalate, dimethyl phthalate, and bisphenol-A). Microbial analysis showed the abundances of vital anaerobes, such as acid-producing bacteria (Acetoanerrobium and Mesotoga), proteolytic bacteria (Proteiniborus), and methanogens (Methanosaeta) clearly decreased with the PE-MP and PVC-MP after the HTP, which might result in the decreased methane production. The study provided deep-insight of MPs' behaviors during the combined HTP-AD process.
More Papers Like This
Microplastic ingestion by fish: Body size, condition factor and gut fullness are not related to the amount of plastics consumed
AI summary Read the abstract
Researchers examined microplastic ingestion in commercial cod and saithe collected in Iceland, finding particles in about 20% of cod and 17% of saithe stomachs. No significant relationship was found between microplastic ingestion and fish body size, weight, gut fullness, or condition index.
Optimization of coagulation and sedimentation conditions by turbidity measurement for nano- and microplastic removal
AI summary Read the abstract
This study assessed microplastic ingestion by commercially important fish species in the Persian Gulf, finding particles in the digestive tracts of all five species examined. Fibers were the most prevalent shape, suggesting textile washing as a primary source.
Microplastic in tissue of naturally exposed fish from a plastic polluted coastal ecosystem- An investigation of the evidence for bioaccumulation
AI summary Read the abstract
Researchers investigated microplastic ingestion and potential bioaccumulation in naturally exposed Atlantic cod (Gadus morhua) from a plastic-polluted coastal ecosystem, examining whether older individuals accumulate higher microplastic concentrations as would be expected if bioaccumulation occurs.
Occurrence and characterization of microplastic content in the digestive system of riverine fishes
AI summary Read the abstract
Researchers found microplastics in 93.8% of riverine fish examined, with polystyrene, polyethylene, and nylon being the most common polymer types concentrated near urban and industrial areas, and small particles (0.025-1 mm) predominating across species.
Microplastics assessment in Arabian Sea fishes: accumulation, characterization, and method development
AI summary Read the abstract
Researchers assessed microplastic accumulation in Arabian Sea fish species, developing optimized digestion protocols and characterizing polymer types to trace contamination sources, finding widespread microplastic ingestion across multiple commercially important fish species.
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.