0
Article Tier 2 Environmental Sources Human Health Effects Marine & Wildlife Nanoplastics Remediation Sign in to save

Oxidation and fragmentation of plastics in a changing environment; from UV-radiation to biological degradation

The Science of The Total Environment 2022 335 citations

AI summary Read the abstract

This review examines how plastics break down in the environment through UV radiation, weathering, and biological processes, producing smaller and smaller fragments including microplastics and nanoplastics. The breakdown process also releases chemical additives and creates particles with altered surface properties that may be more toxic than the original plastic. Understanding these degradation pathways is critical because the secondary particles produced may pose greater risks to ecosystems and human health than the larger plastic debris.

Study Type Environmental

Understanding the fate of plastics in the environment is of critical importance for the quantitative assessment of the biological impacts of plastic waste. Specially, there is a need to analyze in more detail the reputed longevity of plastics in the context of plastic degradation through oxidation and fragmentation reactions. Photo-oxidation of plastic debris by solar UV radiation (UVR) makes material prone to subsequent fragmentation. The fragments generated following oxidation and subsequent exposure to mechanical stresses include secondary micro- or nanoparticles, an emerging class of pollutants. The paper discusses the UV-driven photo-oxidation process, identifying relevant knowledge gaps and uncertainties. Serious gaps in knowledge exist concerning the wavelength sensitivity and the dose-response of the photo-fragmentation process. Given the heterogeneity of natural UV irradiance varying from no exposure in sediments to full UV exposure of floating, beach litter or air-borne plastics, it is argued that the rates of UV-driven degradation/fragmentation will also vary dramatically between different locations and environmental niches. Biological phenomena such as biofouling will further modulate the exposure of plastics to UV radiation, while potentially also contributing to degradation and/or fragmentation of plastics independent of solar UVR. Reductions in solar UVR in many regions, consequent to the implementation of the Montreal Protocol and its Amendments for protecting stratospheric ozone, will have consequences for global UV-driven plastic degradation in a heterogeneous manner across different geographic and environmental zones. The interacting effects of global warming, stratospheric ozone and UV radiation are projected to increase UV irradiance at the surface in localized areas, mainly because of decreased cloud cover. Given the complexity and uncertainty of future environmental conditions, this currently precludes reliable quantitative predictions of plastic persistence on a global scale.

More Papers Like This

Article Tier 2

From Macro to Micro Plastics; Influence of Photo-oxidative Degradation

AI summary Read the abstract

This study used simulated UV aging to investigate how photo-oxidative degradation of common plastics drives fragmentation from macro to micro scale, characterizing the surface property changes and structural breakdown that generate microplastic particles in the environment.

Article Tier 2

Environmental plastics in the context of UV radiation, climate change, and the Montreal Protocol

AI summary Read the abstract

This review examines how UV radiation and climate change interact with environmental plastics to alter their degradation rates and toxic profiles, with particular focus on how ozone depletion affects UV-induced plastic fragmentation. The authors argue that changing UV environments under climate change will accelerate plastic breakdown and increase nanoplastic production in surface waters.

Article Tier 2

Degradation and Fragmentation of Microplastics

AI summary Read the abstract

This review examines the degradation and fragmentation mechanisms that generate secondary microplastics from ocean plastic debris, covering photo-oxidation chemistry, environmental weathering rates, and how different polymer types break down under marine conditions.

Article Tier 2

Photo-oxidation of Micro- and Nanoplastics: Physical, Chemical, and Biological Effects in Environments

AI summary Read the abstract

This review examines how sunlight breaks down micro- and nanoplastics in the environment, changing their surface properties and making them interact differently with pollutants and living organisms. Sun-aged plastic particles can become more toxic to aquatic life and affect soil microbe communities, but many questions remain about these processes under real-world conditions.

Article Tier 2

Aging Process of Microplastics in the Environment

AI summary Read the abstract

This review examines how natural environmental processes — UV radiation, physical abrasion, chemical reactions, and biodegradation — alter the surface, shape, and chemistry of microplastics over time, and how these changes affect their ability to absorb and transport other pollutants. Understanding microplastic aging is critical because weathered particles behave differently than fresh plastic, often becoming more hazardous as pollutant carriers in 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