We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Oxidation enhances the toxicity of polyethylene microplastics to mouse eye: Perspective from in vitro and in vivo
Summary
Researchers found that polyethylene microplastics can damage mouse eyes, reducing tear production, increasing eye pressure, and penetrating into the cornea and retina. Microplastics that had been aged by environmental oxidation were even more toxic to eyes than fresh ones. This is concerning for human eye health because people are constantly exposed to airborne microplastics, and real-world particles are typically weathered and more harmful than those tested in most lab studies.
Microplastics (MPs) are ubiquitously dispersed in the environment, and undergoing the process of oxidation that alters their physical and chemical properties. Eyes, which directly interface with the external milieu, inevitably encounter MPs. Nonetheless, the ophthalmic toxicity of MPs towards organisms remains unclear. In this study, primary mouse corneal epithelial cells (MCECs), C57BL/6 mice, and CX3Crl mice were utilized to evaluate the toxicity and differences between oxidized low-density polyethylene MPs (modified-MPs) and low-density polyethylene MPs (virgin-MPs) on eyes. The results manifested that virgin-MPs and modified-MPs could be endocytosed by primary MCECs, resulting in a range of cellular damage. Furthermore, they could diminish tear secretion, increase intraocular pressure, and could be internalized into cornea and retina in mice, instigating a series of detrimental reactions. Importantly, modified-MPs exhibited heightened toxicity towards mouse eyes, seemingly due to oxidation enhances the interaction between virgin-MPs/modified-MPs and tissues/cells, and leading to the release of toxic substances increased. In conclusion, our discoveries demonstrate that oxidation exacerbates the harm of virgin-MPs to eyes, and are of great significance for evaluating the risk of MPs to ocular health.
Sign in to start a discussion.
More Papers Like This
Microplastics and nanoplastics in the ocular environment: Pathways, toxic effects, and future challenges
This review examines how micro- and nanoplastics may enter and affect the human eye, a topic that has received relatively little research attention. Researchers discuss potential exposure pathways, accumulation in ocular tissues, and mechanisms of harm including oxidative stress, inflammation, and cell death. The study highlights the need for more research on how plastic pollution could impact vision and overall eye health.
Identification of microplastics in human tear fluid and meibum: Implications for dry eye disease pathogenesis
For the first time, researchers confirmed the presence of microplastics in human tear fluid and the oily secretions of the eyelid glands (meibum), with polyethylene being the most common type found. Higher polyethylene levels correlated with worse dry eye disease symptoms. In lab and mouse experiments, polyethylene exposure damaged eye surface cells and triggered inflammation, suggesting airborne microplastics may contribute to dry eye disease.
Micro/nanoplastics and eye health: a review
This review examined the potential effects of micro- and nanoplastics on eye health, finding that ocular exposure can occur through direct contact and oral ingestion, with particles potentially penetrating biological barriers to reach eye tissues. Evidence indicates that these particles may induce adverse effects on the eye surface, elevate intraocular pressure, and cause retinal abnormalities, primarily through oxidative stress and inflammation mechanisms.
New Insights into the Mechanisms of Toxicity of Aging Microplastics
This study showed that UV-aged polypropylene microplastics are significantly more toxic than fresh ones, absorbing more chemicals and generating more harmful reactive oxygen species in seawater. The aged particles caused greater damage to cell membranes in mussels compared to pristine plastics. Since most microplastics in the ocean have been weathered by sunlight, real-world exposure risks may be higher than laboratory studies using new plastics suggest.
The toxic effects of polystyrene microplastic/nanoplastic particles on retinal pigment epithelial cells and retinal tissue
This study found that polystyrene micro and nanoparticles damaged retinal cells in both lab dishes and live mice, causing oxidative stress, mitochondrial dysfunction, and inflammation in the eye. Nanoparticles were able to penetrate into cells and trigger more severe damage than microparticles. With growing use of contact lenses and eye treatments that may introduce plastic particles, these findings raise concerns about microplastic effects on eye health.