We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Micro- and nanoplastic stress intensifies Microcystis aeruginosa physiology and toxin risks under environmentally relevant water chemistry conditions
Summary
Researchers exposed the cyanobacterium Microcystis aeruginosa to environmentally relevant concentrations of micro- and nanoplastics, finding both significantly enhanced algal biomass and microcystin toxin production, with nanoplastics additionally promoting extracellular toxin release.
Microplastics (MPs) and nanoplastics (NPs) have emerged as contaminants of concern in freshwater ecosystems, yet their impacts on cyanobacteria and toxin dynamics under environmentally relevant conditions remain poorly understood. In this study, we investigated the effects of 10 μm MPs and 20 nm NPs at environmentally relevant (0.5 mg L) and projected future (4 mg L) concentrations on Microcystis aeruginosa under simulated, natural ionic conditions. Our results demonstrated that both MPs and NPs significantly enhanced algal biomass and microcystin (MCs) production. MPs primarily promoted intracellular toxin synthesis, while NPs significantly facilitated extracellular MCs release under co-exposure scenarios. Linear mixed-effects modeling and correlation analysis revealed that total MCs accumulation was driven by a combination of increased biomass, elevated per-cell toxin production, and enhanced release. Furthermore, confocal laser scanning microscopy revealed strong spatial colocalization between plastic particles and extracellular polymeric substances (EPS) in high-concentration groups, suggesting potential formation of EPS-plastic microenvironments that may stabilize algal aggregates and prolong toxin persistence in the water column. Our findings highlight that even at environmental concentrations, MPs and NPs can synergistically intensify cyanobacterial toxicity via multiple pathways. These results underscore the need to incorporate EPS-plastic interactions and realistic environmental conditions into future risk assessments of plastic pollution in aquatic systems.
Sign in to start a discussion.
More Papers Like This
Nanoplastics Promote Microcystin Synthesis and Release from Cyanobacterial Microcystis aeruginosa
Researchers discovered that amino-modified polystyrene nanoplastics promote both the production and release of microcystin, a harmful toxin, from the cyanobacterium Microcystis aeruginosa. The nanoplastics inhibited photosynthesis, induced oxidative stress, and damaged cell membranes, which enhanced toxin synthesis and extracellular release. The findings suggest that nanoplastic pollution in freshwater ecosystems could worsen the threat of harmful algal blooms to aquatic ecology and human health.
Nanoplastics promote microcystin synthesis and release from cyanobacterial Microcystis aeruginosa.
Researchers showed that amino-modified polystyrene nanoplastics (PS-NH2) stimulate microcystin synthesis and release in the bloom-forming cyanobacterium Microcystis aeruginosa by inhibiting photosystem II and increasing membrane permeability. This is the first direct evidence linking nanoplastics to enhanced cyanotoxin production in freshwater blooms.
Mechanistic study on the increase of Microcystin-LR synthesis and release in Microcystis aeruginosa by amino-modified nano-plastics.
This study examined how amino-modified nanoplastics increase production and release of the toxin Microcystin-LR in the cyanobacterium Microcystis aeruginosa, revealing the cellular and gene-expression mechanisms behind this enhancement. The findings highlight how nanoplastic pollution can amplify harmful algal bloom toxicity.
Polymer-specific toxicity of microplastics to Microcystis aeruginosa: Growth inhibition, physiological responses, and molecular mechanisms
Researchers exposed the cyanobacterium Microcystis aeruginosa to four polymer types over 12 days and found that all significantly inhibited growth, with PVC causing the greatest inhibition, and identified polymer-specific molecular mechanisms including oxidative stress and photosynthesis disruption.
Ecological risk analysis and prediction of microplastics' effects on Microcystis aeruginosa in freshwater system: a meta-analysis approach
This meta-analysis found that micro- and nanoplastics can both inhibit and stimulate the growth of Microcystis aeruginosa — a harmful algal bloom cyanobacterium — depending on particle size and degradability. Smaller, degradable plastics tend to promote algal growth, suggesting microplastic pollution could worsen toxic algal blooms in freshwater systems used for drinking water.