We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Effect of polyethylene microplastic biodegradation by algae on their sorption properties and toxicity
Summary
Researchers studied how algal biodegradation of high-density polyethylene microplastics changes their ability to adsorb UV filter chemicals. The study found that biofilm formation on microplastic surfaces altered their sorption properties through multiple mechanisms, and that high concentrations of these microplastics inhibited algal growth and reduced protein and chlorophyll levels.
Microplastics (MPs) in aquatic environments constitute an ideal surface for biofilm formation, facilitating or hindering the transport of contaminants. This study aims to provide knowledge on the sorption behavior of high-density polyethylene (μ-HDPE) after algal degradation toward UV filters. Up to now, the oxidation of μ-HDPE using the microalga Acutodesmus obliquus has not been studied. The results obtained by infrared spectroscopy (IR), scanning electron microscopy (SEM), and porosimetry analysis revealed a biofilm formation on the surface of μ-HDPE and the presence of carbonyl and double bond functional groups. Also, this is the first time that the simultaneous sorption of benzophenone (BPh), 4-methylbenzylidene camphor (4MBC), benzophenone 3 (BPh3), and benzophenone 2 (BPh2) onto biofilm-covered HDPE (biofilm-HDPE) in water have been studied. Filters' sorption on biofilm-HDPE particles follows pseudo-second-order kinetics, and film diffusion was the stage that limited the sorption rate. The Langmuir isothermal model describes the adsorption process for 4MBC, BPh, and BPh2 well, and the linear model is fit for the sorption of BPh3. Hydrophobic interactions, van der Waals forces, electrostatic, and π-π bon are the main mechanisms responsible for the sorption. Biological analysis indicated that HDPE at concentrations of 500 mg L inhibits A. obliquus growth and reduces the levels of proteins, sugars, and chlorophylls. In contrast, the activity of antioxidant enzymes and the contents of small molecular weight antioxidants significantly increased in algal cells treated with microplastic. These findings confirm the toxicity of μ-HDPE and demonstrate the induction of defense mechanisms in A. obliquus as a response to environmental pollutants.
Sign in to start a discussion.
More Papers Like This
Induced aging, structural change, and adsorption behavior modifications of microplastics by microalgae
Researchers found that microalgal biofouling caused more significant aging and surface degradation of microplastics compared to river microbial biofouling over a 30-day period. The study suggests that algae-induced aging substantially enhances the ability of polyethylene and PVC microplastics to adsorb organic pollutants like bisphenol analogues, increasing their potential to transport contaminants in the environment.
Interplay of plastic pollution with algae and plants: hidden danger or a blessing?
Researchers tested the ability of three microalgae species to remove microplastics from water through bioadhesion, finding that all three species could adsorb particles onto their surfaces. Removal efficiency depended on particle size, surface charge, and algae cell morphology.
The influence of microplastics on the toxic effects and biodegradation of bisphenol A in the microalgae Chlorella pyrenoidosa
Researchers found that polystyrene microplastics inhibited the biodegradation of bisphenol A (BPA) by the microalga Chlorella vulgaris, with combined exposure showing greater toxicity than either contaminant alone due to BPA adsorption onto microplastic surfaces.
Interactions between polyethylene and polypropylene microplastics and Spirulina sp. microalgae in aquatic systems
Researchers evaluated interactions between polyethylene and polypropylene microplastics and Spirulina microalgae, finding that microplastics inhibited algal growth and pigment production while Spirulina showed limited ability to degrade the plastic surfaces.
Micro-polyethylene particles reduce the toxicity of nano zinc oxide in marine microalgae by adsorption
Researchers discovered that polyethylene microplastic particles reduced the toxicity of zinc oxide nanoparticles to marine microalgae by adsorbing the nanoparticles onto their surface, revealing that microplastics can modify the bioavailability of co-occurring contaminants.