0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Remediation Sign in to save

Contribution of free hydroxyl radical to the formation of micro(nano)plastics and release of additives during polyethylene degradation in water

Environmental Pollution 2023 13 citations ? Citation count from OpenAlex, updated daily. May differ slightly from the publisher's own count. Score: 50 ? 0–100 AI score estimating relevance to the microplastics field. Papers below 30 are filtered from public browse.
Yu Tang, Kaiqing Fan, Indika Herath, Williamson Gustave, Chuxia Lin, Junhao Qin, Rongliang Qiu

Summary

Researchers found that hydroxyl radicals generated from hydrogen peroxide in water significantly accelerate the degradation of polyethylene and the formation of micro- and nano-sized plastic particles. The study, conducted over 620 days, demonstrates that naturally occurring reactive oxygen species in aquatic environments may contribute to the generation and spread of secondary microplastics.

Polymers

The omnipresence of secondary microplastics (MPs) in aquatic ecosystems has become an increasingly alarming public health concern. Hydrogen peroxide (HO) is an important oxidant in nature and the most stable reactive oxygen species occurred in natural water. In order to explore the contribution of free ˙OH generated from HO-driven Fenton-like reactions on the degradation of polyethylene (PE) and generation of micro- and nano-scale plastics in water, a batch experiment was conducted over a period of 620 days in water treated with micromolar HO. The incorporation of HO in water induced the formation of flake-like micro(nano)-sized particles due to intensified oxidative degradation of PE films. The presence of ˙OH significantly enhanced the generation of both micro- and nano-scale plastics exhibiting a higher proportion of particles in the range of 200-500 nm compared to the Control. Total organic carbon in the HO treated solution was nearly 174-fold higher than that of the Control indicating a substantial liberation of organic compounds due to the oxidative degradation of native carbon chain of PE and subsequent decomposition of its additives. The highly toxic butylated hydroxytoluene detected from the gas chromatography-mass spectrometry (GC-MS) analysis implied the toxicological behavior of secondary micro(nano)plastics influenced by the oxidation and decomposition processes The findings from this study further expand our understanding of the role of ˙OH in degrading PE micro-scale plastics into nanoparticles as an implication of naturally occurring HO in aquatic environments. In the future, further attention should be drawn to the underlying mechanisms of HO-driven in-situ Fenton reaction mediated by natural environmental conditions targeting the alternation of light and darkness on the oxidative degradation of plastics.

Sign in to start a discussion.

More Papers Like This

Article Tier 2

Investigations into the Reactivity of Microplastics in Water

Researchers investigated how hydroxyl radicals — naturally occurring reactive molecules in water — chemically transform microplastics, finding that radiation-generated radicals can break plastic bonds and alter their surface properties. Understanding microplastic chemical reactivity in water is important for predicting how environmental degradation changes their biological effects.

Article Tier 2

Fate and environmental behaviors of microplastics through the lens of free radical

Researchers reviewed how free radicals influence the fate and environmental behavior of microplastics, including surface degradation, chemical release, and changes in crystallinity and water affinity. The study found that while free radicals can cause weathering and fragmentation of microplastics in the environment, high concentrations of free radicals with strong oxidation potential can also be harnessed to effectively degrade microplastic pollutants.

Article Tier 2

ROS-mediated photoaging pathways of nano- and micro-plastic particles under UV irradiation

Researchers investigated the role of reactive oxygen species in the photoaging of nano- and micro-plastic particles under UV irradiation. The study found that bare polystyrene nanoparticles generated hydroxyl radicals and singlet oxygen, while surface coatings and larger particle sizes reduced ROS generation. The findings help explain the mechanisms by which UV exposure breaks down plastic particles in aquatic environments.

Article Tier 2

Long-term phototransformation of microplastics under simulated sunlight irradiation in aquatic environments: Roles of reactive oxygen species

Researchers examined the long-term photodegradation of polystyrene microplastics under simulated sunlight in aquatic conditions, finding that reactive oxygen species — particularly hydroxyl radicals and singlet oxygen — were the primary drivers of surface oxidation and fragmentation into nanoplastics.

Article Tier 2

Liberation of plastic nanoparticles and organic compounds from three common plastics in water during weathering under UV radiation-free conditions

Researchers conducted a 620-day weathering experiment on PET, PP, and ABS plastics in water with and without reactive oxygen species, finding that hydroxyl radicals from Fenton-like reactions significantly enhanced nanoplastic generation and release of over 30 organic compounds including potentially toxic plastic additive-derived pollutants, with PET releasing the greatest total organic carbon.

Share this paper