Contact Lenses vs. Glasses: Which Offers Eye Sustainability?

In the dynamic world of eyewear, the choice between contact lenses and glasses is not just about vision correction; it’s about sustainability—both for the environment and for your eyes.

Join The Diplomat News for an in-depth exploration of sustainability as we uncover which has a greater environmental impact: the waste from contact lenses or the manufacturing process of glasses.

Contact lens wearers contribute to waste by discarding old pairs, packaging, and saline solution bottles each time they switch to a new pair.

This waste can add up to about a kilogram (2.2 pounds) per year, even with reusable contacts. Considering the 140 million contact-wearers worldwide, this results in a significant amount of trash.

On the other hand, eyeglasses also pose environmental challenges, especially with half of the global population expected to require spectacles by 2050. Determining the better option for the environment could have a substantial impact.

Contact lenses create microplastics

Contact lenses contribute to the production of microplastics. According to Charles Rolsky, the executive director of the Shaw Institute, approximately 20% of contact lens wearers in the United States dispose of their used lenses by flushing them down the drain. Rolsky’s research for his PhD thesis revealed that between 2 and 3 billion plastic lenses end up in wastewater in the US alone.

Rolsky tracked contact lenses’ journey through a wastewater treatment plant and examined the plant’s final product, biosolids, a nutrient-rich fertilizer. The study demonstrated that the lenses are able to withstand the wastewater treatment process. Their porous nature poses a risk of contamination with diseases or chemicals, and they also break down into microplastics.

Microplastics are minuscule plastic particles that can easily travel through the environment, particularly in water. They can enter the food chain and eventually find their way back to humans.

Another study conducted in 2023 discovered that at least 18 types of contact lenses sold in the US contain high levels of PFAS, also known as forever chemicals. It remains unclear whether wearing contact lenses directly exposes individuals to PFAS, but these toxic chemicals can contaminate soil and water, accumulating in animals before potentially affecting humans.

So, are glasses better than contact lenses?

Contact Lenses vs. Glasses: Which Offers Eye Sustainability?

It’s difficult to determine whether glasses are better than contacts. In the eyewear industry, very few manufacturers publicly disclose their carbon impact, which makes it challenging to assess their environmental impact. However, when it comes to waste production, glasses tend to generate less waste once they are in the hands of consumers. The majority of environmental impact occurs during the manufacturing process.

Typically, manufacturers grind down large pieces of plastic to make the lenses, resulting in a significant amount of waste. The lenses cut away approximately 90% of the original plastic. The frames, which are mostly plastic as well, contribute a similar amount of waste. Overproduction is also a concern in the glasses manufacturing industry.

Scientist Max Juraschek finds that long manufacturing-to-sale timelines and shifting fashion trends result in discarding about half of produced glasses before sale.

Many people in the US purchase a new pair of glasses each year, considering them a fashion accessory. Unfortunately, like other fast fashion items, these frames often end up in landfills.

What are the options for recycling glasses and contacts?

The eyewear industry heavily relies on plastics, which are challenging to recycle. According to Clark, a significant portion of these plastics is derived from fossil fuels. Additionally, the industry’s global nature, with manufacturing primarily taking place in China and the Global East, contributes to a substantial carbon footprint.

In the UK, there are a few programs that claim to recycle both contact lenses and their packaging, as well as glasses. However, contact lenses pose a unique challenge as they are too small to be recycled alongside other plastic waste and cannot be easily separated.

Specialty recycling programs for glasses attempt to separate them into their component materials before transforming the plastics into lower-grade materials, which may eventually end up in landfills. Glass lenses, although an alternative to plastic, also present difficulties in recycling due to the special coatings used on them.

What about durable glass?

Sustainable eyeglasses are a great option to consider. Instead of traditional acetate frames made from a mix of plant-based materials and fossil fuels, some manufacturers are promoting bio-acetate. However, Clark believes this is just a form of greenwashing since it still contains a significant amount of plastic.

“It’s like making a burger. You can’t claim it’s a vegan burger when only 75% of it is actually vegan,” he explained.

Contact lenses or glasses?

Being conscious of waste is a significant choice for those who wear glasses or contact lenses.

Contact lens wearers should refrain from rinsing lenses down the drain – this only pollutes water and the environment with microplastics. Additionally, if feasible, participating in a specialized recycling program could have a positive impact.

Glasses wearers can choose to only replace their lenses and avoid purchasing new frames solely for style.

According to Juraschek’s research team, by moving glasses production closer to consumers and utilizing local recycled materials, the environmental footprint of glasses could be reduced by 25%. A portion of this achievement was due to small-scale manufacturing that minimized overproduction. The team also discovered that customers felt a stronger connection to the product when it was produced locally.