We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Alleviating binary toxicity of polystyrene nanoplastics and atrazine to Chlorella vulgaris through humic acid interaction: Long-term toxicity using environmentally relevant concentrations
AI summary Read the abstract
Researchers found that when nanoplastics and the herbicide atrazine were combined in water, they had a synergistic toxic effect on algae that was worse than either pollutant alone. However, adding humic acid, a natural substance found in soil and water, significantly reduced this combined toxicity by coating the nanoplastics and changing their surface properties. This suggests that natural organic matter in the environment may offer some protection against the harmful effects of nanoplastic-chemical mixtures.
In this study, microalgae Chlorella vulgaris (C. vulgaris) were simultaneously exposed to environmental concentrations of amino-functionalized polystyrene nanoplastics (PS-NH; 0.05, 0.1, 0.2, 0.3 and 0.4 mg/L) and the world's second most used pesticide, the herbicide atrazine (ATZ; 10 μg/L), in the absence and presence of humic acid (HA; 1 mg/L) for 21 days. Due to the low concentrations of PS-NH, the majority of them could not cause a significant difference in the end-points of biomass, chlorophylls a and b, total antioxidant, total protein, and superoxide dismutase and malondialdehyde compared to the control group (p > 0.05). On the other hand, by adding ATZ to the PS-NH, all the mentioned end-point values showed a considerable difference from the control (p < 0.05). The exposure of PS-NH+ATZ treatments to the HA could remarkably reduce their toxicity, additionally, HA was able to decrease the changes in the expression of genes related to oxidative stress (e.g., superoxide dismutase, glutathione reductase, and catalase) in the C. vulgaris in the most toxic treatment group (e.g., PS-NH+ATZ). The synergistic toxicity of the PS-NH+ATZ group could be due to their enhanced bioavailability for algal cells. Nevertheless, the toxicity alleviation in the PS-NH+ATZ treatment group after the addition of HA could be due to the eco-corona formation, and changes in their zeta potential from positive to negative value, which would increase their electrostatic repulsion with the C. vulgaris cells, in such a way that HA also caused a decrease in the formation of C. vulgaris-NPs hetero-aggregates. This research underscores the complex interplay between PS-NH, ATZ, and HA in aquatic environments and their collective impact on microalgal communities.
More Papers Like This
Presence of humic acid in the environment holds promise as a potential mitigating factor for the joint toxicity of polystyrene nanoplastics and herbicide atrazine to Chlorella vulgaris: 96-H acute toxicity
AI summary Read the abstract
Researchers studied how nanoplastics and the herbicide atrazine together affect freshwater algae, and whether humic acid, a natural organic substance found in water, could reduce their combined harm. They found that both the nanoplastics alone and in combination with atrazine damaged algal growth, photosynthesis, and antioxidant defenses. The presence of humic acid significantly reduced these toxic effects, suggesting it may act as a natural buffer against nanoplastic and pesticide pollution in aquatic environments.
Blocking the “Trojan Horse” effect: Humic acid alleviates the combined toxicity of amino-modified nanoplastics and tetracycline to microalgae by inhibiting heteroaggregation and oxidative stress
AI summary Read the abstract
Tiny plastic particles in water can act like a "Trojan Horse," carrying antibiotics into algae and causing more cell damage than either pollutant alone. This study found that humic acid, a natural substance common in soil and water, can block this effect by preventing the antibiotics from sticking to the plastic in the first place. This is good news because it suggests that in real-world waters rich in natural organic matter, nanoplastic pollution may be less harmful to aquatic ecosystems, and the food chain we depend on, than lab studies alone might suggest.
Humic acid can mitigate or magnify nanoplastic toxicity to freshwater microalgae: what are the factors driving these contrasting effects?
AI summary Read the abstract
Researchers explored how humic acid, a natural organic substance found in water, interacts with nanoplastics to either reduce or amplify their toxicity to freshwater microalgae. The study found that humic acid can mitigate nanoplastic toxicity by reducing surface hydrophobicity and improving particle dispersion, but this protective effect diminishes at low humic acid concentrations.
Humic acid alleviates the toxicity of polystyrene nanoplastics in combination with their copper nanoparticle co-pollutants in Artemia salina
AI summary Read the abstract
Researchers examined how humic acid, a natural organic substance found in soil and water, affects the toxicity of polystyrene nanoplastics combined with copper nanoparticles in brine shrimp. They found that humic acid reduced the harmful effects of these co-pollutants, likely by coating the particles and limiting their biological interactions. The study suggests that natural organic matter in the environment may help buffer some of the toxic effects of nanoplastic pollution.
Nano-sized polystyrene plastics toxicity to microalgae Chlorella vulgaris: Toxicity mitigation using humic acid
AI summary Read the abstract
Researchers exposed the green microalga Chlorella vulgaris to amino-functionalized polystyrene nanoplastics and found significant toxicity to biomass and chlorophyll, but adding humic acid — a natural organic matter component — substantially reduced toxicity by coating the nanoplastics' positively charged surfaces and preventing their electrostatic attraction to algal cell walls.
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.