0
Article Tier 2 Sign in to save

Adverse physiological and molecular level effects of polystyrene microplastics on freshwater microalgae

Chemosphere 2020 164 citations

AI summary Read the abstract

Researchers investigated the toxic effects of polystyrene microplastics on the freshwater microalgae Euglena gracilis. The study found that microplastic exposure at 1 mg/L induced vacuole formation within 24 hours and significantly disrupted photosynthesis, with smaller particles (0.1 micrometers) causing more severe cellular damage than larger ones (5 micrometers), suggesting size-dependent toxicity mechanisms.

Polymers
Study Type Environmental

Microplastics have aroused widespread concern because of their adverse effects on aquatic organisms. However, the underlying toxicity mechanisms have not been examined in detail. This study investigated the interactions between polystyrene microplastics (PS-MPs) and the model freshwater microalgae Euglena gracilis. The results of transmission electron microscopy showed that the vacuoles of microalgae were induced after 24 h exposure to 1 mg/L PS-MPs (5 μm and 0.1 μm). Furthermore, PS-MPs significantly (p < 0.05) reduced pigment contents. Moreover, superoxide dismutase activities were significantly (p < 0.05) induced in all PS-MPs treated groups. Peroxidase activities were also significantly (p < 0.05) affected by two sizes of PS-MPs (5 μm and 0.1 μm), indicating that oxidative stress was induced after exposure to PS-MPs. At the molecular level, PS-MPs dysregulated the expression of genes involved in cellular processes, genetic information processing, organismal systems, and metabolisms. The KCS gene and the CTR1 gene may be key pathways to induce adverse effects on the E. gracilis after exposure to 5 μm PS-MPs. These findings will help to elucidate the underlying molecular mechanism of microplastics toxicity on freshwater organisms.

More Papers Like This

Article Tier 2

Toxicity of polystyrene microplastics in freshwater algae Scenedesmus obliquus: Effects of particle size and surface charge

AI summary Read the abstract

Researchers investigated how polystyrene microplastics of different sizes and surface charges affect the freshwater algae Scenedesmus obliquus. The study found that smaller 1-micrometer particles caused greater oxidative stress, reduced photosynthetic effectiveness, and decreased membrane integrity compared to larger 12-micrometer particles, with effects being dose-dependent.

Article Tier 2

Internalization of polystyrene microplastics in Euglena gracilis and its effects on the protozoan photosynthesis and motility

AI summary Read the abstract

Researchers exposed Euglena gracilis protozoa to polystyrene microplastics and found that while photosynthesis was unaffected at tested concentrations, motility was significantly reduced at higher doses, suggesting that microplastics impair locomotion in unicellular flagellates that would normally avoid or evade particles.

Article Tier 2

Size-Dependent Effects of Polystyrene Nanoplastics on Freshwater Microalgae After Long-Term Exposure

AI summary Read the abstract

Researchers exposed a common freshwater algae species to polystyrene nanoplastics of three different sizes over an extended period. They found that the smallest particles caused the most damage to algae cells, while the largest particles had relatively mild effects, revealing a clear size-dependent toxicity pattern. The study suggests that the tiniest nanoplastic particles in freshwater environments may pose the greatest risk to the base of aquatic food webs.

Article Tier 2

The toxic effects of polystyrene microplastics on freshwater algae Chlorella pyrenoidosa depends on the different size of polystyrene microplastics

AI summary Read the abstract

Researchers tested how two sizes of polystyrene microplastics affect the freshwater alga Chlorella pyrenoidosa, an important organism at the base of aquatic food webs. They found that smaller microplastics caused more severe damage to algal growth, photosynthesis, and cellular health than larger ones, with effects worsening over time and at higher concentrations. The study demonstrates that microplastic size is a critical factor determining toxicity to aquatic phytoplankton.

Article Tier 2

Toxicity Effects of Polystyrene Nanoplastics with Different Sizes on Freshwater Microalgae Chlorella vulgaris

AI summary Read the abstract

Researchers tested how two sizes of polystyrene nanoplastics (50 nm and 70 nm) affected the common freshwater microalgae Chlorella vulgaris. Both sizes reduced algae growth, chlorophyll content, and photosynthetic activity in a dose-dependent manner, with the smaller particles causing more damage. Since microalgae form the base of aquatic food chains, their sensitivity to nanoplastics could have cascading effects on entire freshwater ecosystems.

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.

Email me about

Share this paper