DAILY DISPOSABLE (DD) contact lenses (CLs) accounted for almost 50% of new fits in 2022 (Morgan et al, 2023). However, there are growing concerns about their environmental impact, particularly as consumers adopt “zero waste” lifestyle choices.

For context, full-time DD use generates a little over 1kg of waste a year (Smith, Orsborn et al, 2022), which is small compared to the volume of waste generated from other daily activities (Figure 1), equating to approximately 0.26% of typical household waste generated by an average person in the United Kingdom (Smith, Orsborn et al, 2022) or 0.13% in the U.S. (author’s own calculation; based on an average of 2.2kg of waste generated per person in the U.S. per day) (Smith, Orsborn et al, 2022; U.S. Environmental Protection Agency, 2022; Routhier et al, 2012). Compared to full-time reusable CL wear, when care products and lens cases are included, DD use generates approximately only 20% more total waste (Smith, Orsborn et al, 2022).

WHAT TO DO WITH CL WASTE

One hundred percent of waste arising from DD lenses can be recycled (Smith, Orsborn et al, 2022) and needs to be appropriately disposed of to further reduce environmental harm. Table 1 lists components, materials, and the disposal route.

Household recycling will accept the cardboard carton that forms the external packaging, and the remaining components are readily handled by specialist recycling companies. Typically, plastic items smaller than 3 inches often fall through the automated conveyor belts at the sorting facilities (Smith, Takkellapati et al, 2022), and laminated foils can be difficult or costly to recycle (Smith, Orsborn et al, 2022). The specialty recyclers address the issue that foils, blister trays, and CLs may not always be readily recyclable via household schemes offered by all municipalities.

Participating practices receive a recycling bin from the specialty recycling company that accepts the CL waste collected and brought in by patients. When the bin is full, the practice sends the container back to the recycler using a prepaid shipping label. The collected materials are recycled into postconsumer products, such as furniture or gardening equipment. Patients should be reminded that all brands of CL packaging are accepted under this initiative.

It is crucial to remind patients to avoid flushing their used CLs down the toilet or sink. These inappropriate disposal methods contaminate wastewater systems with devastating consequences. Large and small fragments of CLs have been recovered from sewage sludge (Rolsky et al, 2020). This might appear inconsequential; however, since 50% of treated sewage sludge in the U.S. is used as fertilizer in agriculture (Cha and Cupples, 2009), this can potentially introduce more plastics into the food chain. The harm of microplastics on marine life is also of great concern. While the full effects on marine health are unknown, mortality, morbidity, and reproduction are known to be affected (Cole et al, 2011). This raises the question of how our daily choices can impact vulnerable aquatic ecosystems.

CONCLUSION

Waste is unavoidable with CL wear, but recycling programs exist that can empower patients to be more responsible with disposing their CL waste properly. CLS

References

1. Morgan P, Woods C, Tranoudis IG, et al. International Contact Lens Prescribing in 2022. Contact Lens Spectrum. 2023 Jan;38:28-35.
2. Smith SL, Orsborn GN, Sulley A, Chatterjee NB, Morgan PB. An investigation into disposal and recycling options for daily disposable and monthly replacement soft contact lens modalities. Cont Lens Anterior Eye. 2022 Apr;45:101435.
3. U.S. Environmental Protection Agency. National Overview: Facts and Figures on Materials, Wastes and Recycling. 2022 Dec 3. Available from epa.gov/facts-and-figures-about-materials-waste-and-recycling/national-overview-facts-and-figures-materials . Accessed May 3, 2023.
4. Routhier J, De Freitas M, Hickson-Curran S. Daily disposable versus reusable contact lenses: a close match when it comes to the impact on the environment. Cont Lens Anterior Eye. 2012 Dec 1;35:e2.
5. Smith RL, Takkellapati S, Riegerix RC. Recycling of Plastics in the United States: Plastic Material Flows and Polyethylene Terephthalate (PET) Recycling Processes. ACS Sustain Chem Eng. 2022 Feb 2;10:2084-1096.
6. Rolsky C, Kelkar VP, Halden RU. Nationwide Mass Inventory and Degradation Assessment of Plastic Contact Lenses in US Wastewater. Environ Sci Technol. 2020 Oct 6;54:12102-12108.
7. Cha J, Cupples AM. Detection of the antimicrobials triclocarban and triclosan in agricultural soils following land application of municipal biosolids. Water Res. 2009 May;43:2522-2530.
8. Cole M, Lindeque P, Halsband C, Galloway TS. Microplastics as contaminants in the marine environment: a review. Mar Pollut Bull. 2011 Dec;62:2588-2597.