Article

CONTACT LENS DESIGN & MATERIALS

THINKING GREEN IN CONTACT LENSES

When recommending a switch from monthly or two-week replacement lenses to daily disposables, patients may express concerns about the environmental impact of discarding lenses every day, and they may also ask about contact lens waste among replacement modalities and whether lens-associated materials are recyclable.

Let’s Look at the Numbers

According to a study in 2012, the weight of an annual supply of dehydrated daily disposable lenses (730) was found to be 11.36 grams, or the average waste created by 2.3 credit cards (Routhier et al, 2012). Other than the recyclable cardboard packaging and plastic blister packs, there is not much other waste.

Non-daily-disposable modalities produce extra waste from solution bottles and storage cases in addition to the contact lenses and blister packs. The waste from one bottle of multipurpose contact lens solution is equivalent to more than a 2.5-year supply of daily disposables. One multipurpose lens case and a peroxide lens case is equivalent to a four- and eight-year supply of daily disposable lenses, respectively.

With reusable lenses, much of the environmental impact relates to the cleaning, rinsing, and disinfection solutions. First, bottles for each solution must be produced, which generates some level of chemical waste resulting from the manufacturing process. Then, the finished bottles are shipped to the solution manufacturer, which fills and seals the bottles, boxes them up, and ships them to various distributors. Next, the distributors ship the bottles to retail locations. After that, consumers drive to the store and purchase the product. Therefore, the carbon footprint of the manufacturing of the care products, the shipping by either air or truck, and the resultant multiple bottles and cases needing to be recycled far outweighs any environmental impact from discarding a new pair of lenses and their packaging every day.

What About Recycling?

Any discussion of waste and environmental impact must also consider recycling. Contact lenses, opened blister packs, plastic solution bottles, storage cases, and cardboard box packaging can all be recycled. Many drop-off locations and recycling options may be found online. For example, #5 polypropylene plastic blister packs can be recycled through the Preserve Products Gimme 5 Program, and certain contact lens companies provide free shipping labels so patients may recycle in the comfort of their own home. One company even supports in-office and patient-specific recycling programs and will donate to a cause for every pound recycled.

Soft contact lenses, blister packs, and plastic molds are not biodegradable. Therefore, they are recycled and transformed into products such as clothes hangers, domestic bin liners, etc. New advancements may allow for soy-based biodegradable contact lens products in the future.

In Summary

While the initial impression may be that discarding a new pair of lenses and their packaging every day might be environmentally unfriendly, assure patients that the environmental impact of daily disposables is in fact far less compared to replacement modalities that require solutions and cases. They should also know that contact lens waste of any kind (solutions, bottles, lenses, packaging, and shipping all considered) accounts for less than 0.5% of total personal waste. CLS

For references, please visit www.clspectrum.com/references and click on document #268.