We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Effects of UV-based oxidation processes on the degradation of microplastic: Fragmentation, organic matter release, toxicity and disinfection byproduct formation
AI summary Read the abstract
This study examined how UV-based water treatment processes break down microplastics, finding that while the treatments fragment the plastics into smaller pieces, they also release potentially toxic organic compounds. The smaller fragments and released chemicals may actually pose greater risks than the original microplastics. This is an important finding because it suggests that some water purification methods could unintentionally make microplastic pollution more hazardous to human health.
The occurrence and transformation of microplastics (MPs) remaining in the water treatment plants has recently attracted considerable attention. However, few efforts have been made to investigate the behavior of dissolved organic matter (DOM) derived from MPs during oxidation processes. In this study, the characteristics of DOM leached from MPs during typical ultraviolet (UV)-based oxidation was focused on. The toxicity and disinfection byproduct (DBP) formation potentials of MP-derived DOM were further investigated. Overall, UV-based oxidation significantly enhanced the aging and fragmentation of highly hydroscopic MPs. The mass scales of leachates to MPs increased from 0.03% - 0.18% at initial stage to 0.09% - 0.71% after oxidation, which were significantly higher than those leached by natural light exposure. Combined fluorescence analysis with high resolution mass spectrometer scan confirmed that the dominant MP-derived DOM are chemical additives. PET-derived DOM and PA6-derived DOM showed inhibition of Vibrio fischeri activity with corresponding EC of 2.84 mg/L and 4.58 mg/L of DOC. Bioassay testing with Chlorella vulgaris and Microcystis aeruginosa showed that high concentrations of MP-derived DOM inhibited algal growth by disrupting the cell membrane permeability and integrity. MP-derived DOM had a similar chlorine consumption (1.63 ± 0.41 mg/DOC) as surface water (1.0 - 2.0 mg/DOC), and MP-derived DOM mainly served as precursors for the investigated DBPs. Contrary to the results of previous studies, the DBP yields from MP-derived DOM were relatively lower than those of aquatic DOM under simulated distribution system conditions. This suggests that MP-derived DOM itself rather than serving as DBP precursor might be potential toxic concern.
More Papers Like This
Insight into the effect of UVC-based advanced oxidation processes on the interaction of typical microplastics and their derived disinfection byproducts during disinfection
AI summary Read the abstract
Scientists found that UV-based water treatment processes, while intended to clean drinking water, caused microplastics to release more organic matter and form more disinfection byproducts during chlorination. Up to 42% of the toxic byproducts formed were absorbed back onto the microplastic surfaces, creating contaminated particles. This concerning finding suggests that some common water treatment methods could unintentionally make microplastic contamination in drinking water more hazardous.
Unveiling the optical and molecular characteristics of aging microplastics derived dissolved organic matter transformed by UV/chlor(am)ine oxidation and its potential for disinfection byproducts formation
AI summary Read the abstract
Researchers studied how UV light and common water disinfection chemicals break down microplastics in water and found that different treatment methods produce different types of dissolved organic matter from the plastic. Some treatment combinations, particularly UV with chlorine, created byproducts that could form harmful disinfection byproducts when water is later chlorinated. This is important because it means water treatment processes might unintentionally create new toxic compounds from the microplastics already present in water.
Fate and potential risks of microplastic fibers and fragments in water and wastewater treatment processes
AI summary Read the abstract
Researchers tested how different water treatment steps handle microplastic fibers and fragments, finding that sand filtration was most effective at 98% removal, while activated sludge and chemical treatment removed only 55-61%. Importantly, UV-based disinfection caused microplastic fragments to release dissolved chemicals that were toxic to cells and bacteria. This study reveals that some water treatment processes, while removing visible microplastics, may inadvertently create new chemical hazards from the plastic particles they break down.
Transformation of microplastics during UV-LED based water disinfection: Mechanistic insights and environmental implications
AI summary Read the abstract
Researchers investigated how UV-based water disinfection treatments transform the physical and chemical properties of common microplastics like polystyrene, polyethylene, and PVC. They found that treatment created surface cracks, reduced water repellency, and generated various breakdown compounds, some of which showed toxicity to aquatic organisms. The study highlights that while UV disinfection effectively treats pathogens, it may inadvertently create new environmental risks by altering microplastics in the water supply.
Effects of UV light on physicochemical changes in thermoplastic polyurethanes: Mechanism and disinfection byproduct formation
AI summary Read the abstract
Researchers examined how UV light exposure changes the properties of thermoplastic polyurethane microplastics in water and whether those changes affect the formation of harmful disinfection byproducts during water chlorination. They found that UV exposure broke the plastic into smaller fragments and released soluble chemicals that significantly increased byproduct formation after chlorination. The findings suggest that aging microplastics in water systems could contribute to the creation of potentially harmful chemicals during standard water treatment.
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.