We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microplastics found in Antarctic penguins: chemical reactivity theory to analyze possible toxicity
AI summary Read the abstract
Researchers used quantum chemistry calculations to compare the toxicity of polyethylene and polyester microplastics found in Antarctic penguins. Although penguins contained far more polyethylene, the study found polyester to be the more chemically dangerous polymer because it acts as a better oxidant, forms stronger molecular interactions, and can disrupt DNA base pairs. These findings suggest that even small amounts of polyester microplastics in wildlife may pose serious biological risks.
Abstract Micro- and nanoplastics are widespread in the marine environment including polar regions across Antarctica. In Antarctic penguins, eighty percent of microplastics were identified as polyethylene and ten percent as polyester. To analyze the toxicity of these two polymers, oligomers with different numbers of units were used as models. The use of oligomers as polymer models has been used previously with success. We started with the monomer and continued with different oligomers until the chain length was greater than 2 nm. According to the results of quantum chemistry, polyester is a better oxidant than polyethylene, since it is a better electron acceptor. Although there is less polyester than polyethylene in penguins, the presence of polyester may be more harmful than the presence of polyethylene for three reasons: polyester is better electron acceptor and therefore a better oxidant than polyethylene; polyester has negatively charged oxygen atoms and can promote stronger interactions than polyethylene with other molecules; polyester forms stable complexes and can dissociate the guanine-cytosine nucleobase pair. This could affect DNA replication. This theoretical information helps to elucidate the potential damage of micro- and nanoplastics.
More Papers Like This
Chemical reactivity theory to analyze possible toxicity of microplastics: Polyethylene and polyester as examples
AI summary Read the abstract
Using computer modeling of molecular chemistry, researchers found that polyester (PET) microplastics are more chemically reactive and potentially more toxic than polyethylene (PE) microplastics. PET was shown to be a stronger electron acceptor with negatively charged atoms that can interact with biological molecules, and it was able to disrupt the bonding between DNA base pairs in simulations. While these are theoretical predictions, the findings suggest that PET microplastics from clothing and packaging may pose greater risks to cellular health than plastic bag microplastics.
Effects of polyethylene and polypropylene microplastics on the DEP degradation mechanisms initiated by •OH and SO4•- in aquatic environments
AI summary Read the abstract
Researchers used computational chemistry to investigate how polyethylene and polypropylene microplastics affect the breakdown of the plasticizer chemical diethyl phthalate by reactive radicals in water. They found that the microplastics altered the electronic properties of the pollutant and changed its degradation pathways, with some breakdown products being more toxic than the original chemical. The study highlights the importance of considering microplastic interactions when assessing the environmental fate of chemical pollutants.
The binding between amino acids and microplastics: a quantum chemistry study into the interactions of model systems and the prospect of extending to larger aggregates
AI summary Read the abstract
Computer modeling was used to study how amino acids, the building blocks of proteins, stick to small microplastic molecules, finding that hydrogen bonds and other chemical attractions drive this binding. The study also tested several computational methods to find faster ones suitable for studying larger, more realistic microplastic systems in future research.
Novel insights into photoaging mechanisms and environmental persistence risks of polylactic acid (PLA) microplastics: Direct and indirect photolysis
AI summary Read the abstract
Using quantum chemical calculations and kinetic simulations, researchers investigated the photoaging mechanisms of polylactic acid (PLA) -- a supposedly biodegradable plastic -- under UV radiation. PLA underwent both direct photolysis and indirect photolysis via reactive oxygen species, producing persistent microplastic fragments, raising concerns that PLA's environmental persistence under real-world sunlight conditions may exceed expectations.
A Thermodynamic Approach for Assessing the Environmental Exposure of Chemicals Absorbed to Microplastic
AI summary Read the abstract
Researchers used thermodynamic and multimedia modeling to assess how microplastics influence the transport and bioavailability of persistent toxic substances in marine environments. The study suggests that chemicals with high hydrophobicity may partition to polyethylene microplastic, but overall, microplastic is likely of limited importance as a vector for delivering toxic substances to marine organisms compared to other exposure pathways.
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.