The Earth: Still Worth Fighting For

In one of his more optimistic moods, Ernest Hemingway once wrote, “The Earth is a fine place and worth fighting for.” Of course, when writing this (in his 1940 Spanish Civil War novel, For Whom the Bell Tolls) the author wasn’t referring to the climate crisis. But in contemporary climate change campaign messaging, the phrase has a new urgency. The world is truly a beautiful place, and it still is definitely worth fighting for.

Eighty-five years on from Hemingway’s novel, climate change and greenhouse gas emissions are some of the biggest problems the world faces. Earth Overshoot Day is the date when humanity's demand for ecological resources and services in a year exceeds what the Earth can renew in that same given year. Back in 1970, the date of Earth Overshoot Day was, quite reassuringly, December 29. In 2025, it is July 24 (1), which means that we’ve essentially already used up our resources for the year…

The healthcare sector plays a significant role in the climate crisis. According to data from the World Bank and World Health Organization (WHO), as of 2020 the healthcare sector was responsible for 4-5 percent of global CO2 equivalent emissions (2). And with over four billion lbs of waste generated annually in the US, healthcare ranks as the second-largest waste producer after the food sector (3).

Global efforts to reduce healthcare's carbon footprint have gained significant momentum. By May 2024, 82 countries were committed to providing more sustainable healthcare through the WHO-led Alliance for Transformative Action on Climate Change and Health (ATACH), and research into the subject is expanding every day (4).

As ophthalmologists, we are faced with our own questions of what we can do to help mitigate the health sector’s environmental impact. The crucial role ophthalmology plays within healthcare is clear-cut – it serves patients of all ages, from newborns to elders, treats common issues and chronic diseases, and performs millions of surgeries and intravitreal injections each year. In the UK, ophthalmology emerges as the highest-volume specialty, accounting for 8.1 percent of outpatient visits in 2018-19 (5). In the US, by 2021 there were around four million cataract surgeries performed annually; this number has now reached around 28 million worldwide – a total of around 75,000 each day (6).

Fortunately, ophthalmology’s awareness of sustainability is increasing. EyeSustain, an organization that offers education and research on sustainability in ophthalmology, is supported by 50 global ophthalmology associations, provides a wealth of useful content, including studies, articles, lectures, and position papers. Similarly, the Eyefficiency app is a worldwide tool for benchmarking cataract surgery sustainability and efficiency, allowing users to monitor their performance over time and evaluate the improvements they are making to their practice.

Knowledge on the topic has also been expanding within ophthalmic hospitals themselves. In the cataract surgery space, for example, we have the Aravind Eye Care System, which includes numerous ophthalmology clinics around India, and regularly reuses various materials in operating rooms, such as gowns, irrigation/aspiration tubes, irrigation bottles, blades, and cannulas. This practice has helped reduce the carbon footprint of a single cataract surgery from 181.8 kg CO2 equivalent in the UK to 6 kg CO2 equivalent, and their rates of endophthalmitis are now even lower than the US (7). Also in India is Mahatma Eye Hospital, which, inspired by pandemic precautions, totally reorganized its outpatient clinics so as to successfully reduce the hospital's total monthly electricity use from 22,000 to 13,000 kilowatt-hours (8).

Given these examples, we can see that ophthalmologists are genuinely invested in taking sustainable actions in their practice. But if we are to contribute in an ever more efficient way towards WHO’s Sustainable Development Goals, as well as truly honor the hopeful sentiment of Hemingway’s oft-repeated quote, then we need to continue to focus on the future of the industry and how it is regulated, and help to raise further awareness about sustainability and its impact to those in leadership roles.