From the Guidelines
Contact lenses can potentially contribute to microplastic exposure, though the risk appears to be minimal. Most modern contact lenses are made from silicone hydrogel or hydrogel materials, which are technically classified as plastics. When these lenses are disposed of improperly (flushed down toilets or sinks), they can break down into microplastics in the environment. Additionally, during normal wear, microscopic fragments might shed from the lenses, though research on this specific exposure route is limited. To minimize any potential risk, users should follow proper lens care protocols, including using fresh solution daily for reusable lenses, adhering to recommended replacement schedules (daily, bi-weekly, or monthly as prescribed), and disposing of lenses properly in solid waste rather than flushing them. The health benefits of properly prescribed and maintained contact lenses generally outweigh the theoretical microplastic exposure risk for most users. The eye has natural defense mechanisms that help protect against foreign particles, and contact lenses are designed and tested for biocompatibility with ocular tissues 1.
Some key points to consider:
- Daily disposable lenses have been shown to significantly reduce the relative risk of microbial keratitis compared with planned replacement soft contact lenses and rigid gas permeable contact lenses 1.
- Hydrogen peroxide systems are superior to multipurpose solutions for reducing the likelihood of infections or inflammatory complications 1.
- No-rub cleaning, topping off (reuse) of solutions, contaminated lens cases, exposure to tap water, wearing contact lenses in hot tubs and showers and while swimming, and changes in water supply are associated with Acanthamoeba and fungal keratitis related to contact lens wear in the recent decades 1.
- Adverse events related to FDA-approved drugs and devices should be reported to MedWatch (www.fda.gov/medwatch) 1.
Overall, while there is a potential risk of microplastic exposure from contact lenses, the risk is minimal and can be mitigated by following proper lens care protocols and disposing of lenses properly. The health benefits of properly prescribed and maintained contact lenses generally outweigh the theoretical microplastic exposure risk for most users.
From the Research
Microplastic Exposure through Contact Lenses
- Contact lenses can release microplastics, with an estimated 90,698 particles released from a pair of contact lenses during a year of wearing 2.
- The microplastics released from contact lenses can be a source of direct exposure to humans, highlighting the need to assess potential health risks caused by eye exposure to microplastics 2.
Pathways of Microplastic Exposure
- Microplastic exposure can occur through ingestion, inhalation, and dermal contact, including contact with contaminated products like contact lenses 3, 4.
- The presence of microplastics in the environment and in products can lead to inevitable human exposure, with potential effects on human health 3, 4, 5.
Potential Health Effects of Microplastic Exposure
- Microplastic exposure may cause particle toxicity, oxidative stress, inflammatory lesions, and increased uptake or translocation in the human body 3, 4, 5.
- Chronic exposure to microplastics is anticipated to be of greater concern due to the accumulative effect that could occur, with potential impacts on human health including immune and stress responses, and reproductive and developmental toxicity 4, 5.