We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Characterization of cell responses in Rhodomonas baltica exposed to PMMA nanoplastics
Summary
Researchers exposed the marine microalga Rhodomonas baltica to PMMA nanoplastics and found effects on cell growth, photosynthesis, and membrane integrity, demonstrating that this important alga — often used as aquaculture feed — is sensitive to nanoplastic contamination.
Due to their small size, nanoplastics (NPLs) possess specific properties which can potentiate their toxicity towards aquatic organisms. As primary producers, microalgae are at the base of aquatic food chains, thus negative impacts of NPLs will likely lead to disturbances in ecosystem productivity. The majority of data available on the toxicity of NPLs is limited to polystyrene and green microalgae, leaving a significant lack of knowledge on impacts of other polymer types across different taxonomic groups. So, the main objective of this study was to evaluate the cell responses of the red microalgae Rhodomonas baltica to plain and carboxylated poly(methyl methacrylate) NPLs (PMMA and PMMA-COOH, 50 nm). Results showed different NPL behaviour in media over time, with PMMA forming micro-scale aggregates and PMMA-COOH maintaining its nominal size range. PMMA caused a higher impact in cellular and physiological parameters than PMMA-COOH, even though a decrease in algal growth was only seen for the later. Overall, PMMA caused a significant decrease in cell viability followed by an increase in cell size and complexity, overproduction of pigments, loss of membrane integrity, hyperpolarization of the mitochondrial membrane, increased production of ROS and LPO, decrease in DNA content and reduced photosynthetic capacity. Conversely, a decrease in algal growth for PMMA-COOH was connected to an impairment in cell cycle and consequent decrease in cell viability, metabolic activity and photosynthetic performance, with negligible effects in ROS formation and pigments content. This study provided a first insight into the mechanistic understanding of the toxic impacts of PMMA and PMMA-COOH NPLs in red microalgae. Results obtained suggest an interaction between both NPLs and R. baltica cell surface that is dependent on particle behaviour and surface chemistry. Future experiments focusing on the in-depth characterization of the mode of action of these particles are recommended.
Sign in to start a discussion.
More Papers Like This
Polystyrene nanoplastics cause growth inhibition, morphological damage and physiological disturbance in the marine microalga Platymonas helgolandica
Researchers exposed marine green microalgae to polystyrene nanoplastics and found significant growth inhibition, increased membrane permeability, disrupted photosynthesis, and visible morphological damage — including surface fragmentation and cellular rupture — at concentrations as low as 200 µg/L.
Impact of Nanoplastics on the Functional Profile of Microalgae Species Used as Food Supplements: Insights from Comparative In Vitro and Ex Vivo Digestion Studies
Researchers assessed how polystyrene and polyethylene nanoplastics affect microalgae species used as food supplements, both before and after simulated digestion. The study found that nanoplastics persisted through the digestion process, altered particle behavior in the microalgae medium, and significantly increased total phenolic content, raising concerns about food safety when plastic contamination occurs.
Evaluating physiological responses of microalgae towards environmentally coexisting microplastics: A meta-analysis
A meta-analysis of 52 studies found that microplastics inhibit microalgal growth and photosynthesis and induce oxidative damage, though microalgae can recover over time. Cyanobacteria are more vulnerable than green algae, and the relative size of microplastics to algal cells governs the mechanism of impact, while aged versus pristine microplastics have opposite effects on extracellular polymeric substance and microcystin production.
Elucidating the cellular adaptive response of Coccomyxa sp. upon exposure to PVC-nanoplastics (PVC-NPs) for production of bioenergy molecules
Researchers studied how the microalga Coccomyxa sp. responds at the cellular level to exposure to PVC nanoplastics. The study aimed to elucidate the mechanisms of nanoplastic interactions with microalgae, which has significant ecological implications for understanding how plastic pollution affects primary producers in aquatic food webs.
Influence of microplastics on the toxicity of chlorpyrifos and mercury on the marine microalgae Rhodomonas lens
Researchers examined how polyethylene microplastics influence the toxicity of chlorpyrifos and mercury to the marine microalga Rhodomonas lens, finding that microplastics can modify pollutant bioavailability and alter toxic effects depending on particle surface oxidation state.