We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Characterization of microplastic degradation in marine ecosystems using spectrometric techniques of stable isotopes and infrared
AI summary Read the abstract
Researchers exposed three types of microplastics — polyethylene pellets, polystyrene balls, and polypropylene mask pieces — to seawater with and without light, and to in-situ conditions at two sites on the Brazilian coast with different pollution levels. Infrared spectroscopy showed that light exposure accelerates surface degradation, and that environmental conditions at polluted urban sites cause faster weathering than cleaner ones. The study provides evidence that sunlight and local pollution levels both influence how quickly marine microplastics break down and change their chemical properties.
Microplastics (MPs) are plastics with size lower or equal to 5 mm. For this experimental study, we selected two primary microplastics, polyethylene (PE) pellets and polystyrene (PS) microballs, and a secondary, polypropylene (PP) mask pieces, and we exposed them in five different treatments. The MPs were exposed to seawater/light, seawater/darkness and ultrapure water/darkness with photoperiod cicles of 12 hours and total darkness. Simultaneously, the MPs were exposed to degradation in situ at Guanabara Bay, Niterói and at Cabo Frio Island, Arraial do Cabo, both at Brazilian Coast, to compare environments with different urbanization and pollution levels. In order to characterize, calculate degradation indexes and compare the microplastics changes in bond structures using Fourier Transform Infrared (FTIR) Spectroscopy and Elemental Analyser (EA). Carbonyl index and C-O index was calculated using the FTIR interest peaks of changes in chemical bonds structures (carbonyl groups, 1509 - 1780 cm⁻¹, and carbon-oxygen, 950 - 1200 cm⁻¹), using references peaks to identify PP (1394 - 1500 cm⁻¹ and 2885 - 2940 cm⁻¹ ) as denominator. Polypropylene preliminary results shows the most increase for both indexes in sea/light treatment during 14 days, but in 28 days the index reduced. As long as for the experimental in situ the index increases significantly. In Guanabara Bay, we observed growth of foraminifera in the MPs after one month, that is possible to see in FTIR results, there was an increase in the peak of carbonate (866 - 887 cm⁻¹). Our preliminary results show changes in the molecular composition of evaluated MPs as well as the advancement of biofilm formation and clusters between MPs and foraminifera along one month of experiments. With the advancement of the incubation, we hope to elucidate the relationship between assessed variables in order to understand the fate of MPs and their impacts on marine ecosystems. Also see: https://micro2022.sciencesconf.org/427853/document
More Papers Like This
Modelling the Photodegradation of Marine Microplastics by Means of Infrared Spectrometry and Chemometric Techniques
AI summary Read the abstract
Researchers modeled the photodegradation of polyethylene and polypropylene marine microplastics using infrared spectrometry and chemometric techniques, tracking structural and chemical changes during accelerated UV aging that simulated five years of solar exposure.
Characterizing photochemical ageing processes of microplastic materials using multivariate analysis of infrared spectra
AI summary Read the abstract
Researchers tracked how four common plastic types weather under UV light and sunlight over six months, using infrared spectroscopy and multivariate analysis to characterize surface chemistry changes. They found that polypropylene weathered fastest, while all plastics showed photooxidation at different rates depending on light source. The study proposes a multivariate spectral approach as a more broadly applicable method than the traditional carbonyl index for assessing microplastic aging.
Characterizing photochemical ageing processes of microplastic materials using multivariate analysis of infrared spectra
AI summary Read the abstract
Scientists studied how sunlight breaks down tiny plastic particles (microplastics) that end up in our environment, finding that different types of plastic degrade at very different rates when exposed to UV light. This matters because as these plastics break down and change chemically, they may become better or worse at picking up and carrying harmful chemicals that could eventually reach humans through food and water. The research helps us better understand how long different plastics persist in nature and how their ability to transport pollutants changes over time.
Microplastic fouling: A gap in knowledge and a research imperative to improve their study by infrared characterization spectroscopy
AI summary Read the abstract
Researchers analysed 4,042 infrared spectra of polystyrene, polyethylene, and polypropylene microplastics collected from the Mediterranean Sea using principal component analysis, identifying that spectral variability in weathered marine microplastics is primarily driven by three processes: chemical ageing, organic fouling, and inorganic fouling.
Polymer weathering under simulated solar radiation and comparison to stormwater and estuarine microplastics
AI summary Read the abstract
Researchers weathered polyethylene and polypropylene plastics under simulated sunlight in water for 90 days and compared their spectral changes to those found in environmental microplastics from stormwater and estuaries. They found that polypropylene degraded faster than polyethylene and that spectral databases had difficulty accurately identifying heavily weathered plastics. The study highlights challenges in identifying and age-dating microplastics found in the environment.
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.