Green oriented practical tips encompass a reorganisation of waste disposal and pathology testing at single centres which may result in a reduction of the carbon footprint of cancer care globally
When I think of the over fifty tubes of blood for nearly 1,000 single laboratory tests collected from my patients every day, I wonder how much I have harmed the environment with my actions while trying to help people with cancer. Can I do anything as a medical oncologist to be more on the green side?
The carbon footprint of healthcare represents an estimated 4-6% of all global emissions (BMJ 2020;371:m3785). Around 17% of healthcare-related emissions come from direct operations and transport, 12% from electricity consumption, while the remaining 71% comprises all other indirect emissions (e.g. embedded carbon in purchased supplies and equipment, employee commuting, waste disposal). As discussed at the ESMO Climate Change Task Force Forum during the ESMO Congress 2023, while the control over direct sources is mostly dependent on national or local policies and healthcare management, each healthcare professional can contribute to reducing environmental impact by acting on indirect sources.
The healthcare system is a source of extensive amounts of waste. Most cannot be avoided, but smart recycling, waste segregation, or reuse strategies can help mitigate their environmental impact. According to WHO only 15% of medical waste is considered hazardous. For the remaining non-hazardous waste, it is key to promote proper segregation and recycling. It has been calculated that of all the plastic waste generated in the operating room, almost 84% is recyclable, but more precise estimations for oncology departments are still lacking (Waste Manag Res. 2019 Jan;37(1):3-19). A common misconception is that items that come into physical contact with a patient correspond to hazardous material and are to be disposed of in biological waste bins (gloves, masks, gowns, or drapes). Most of them are classified as general waste unless they are visibly soiled with body fluids. More careful waste disposal could lead to reducing the amount of red bags for biohazardous waste, reducing resources needed for their utilisation with autoclaving, chemical disinfection, or burning, and ultimately decreasing the volume of CO2 emissions.
Reuse practices can help minimise the amount of substances entering the healthcare waste stream. Decreasing disposable single-use devices in favour of reusable medical equipment can positively impact on reducing waste and the need for additional procurement.
Oncology care is inevitably connected with extensive blood sampling and testing, in research setting as well as in routine clinical practice. But do we really require all the tests we order on a daily basis? Couldn’t we monitor patients less often while controlling disease progression and treatment effects properly? By knowing the frequency and time of occurrence of specific adverse events, for instance, blood tests can be ordered in a more personalised manner. Hepatitis in patients treated with immune checkpoint inhibitors is usually observed within the first 7-8 weeks, so more intensive liver function tests should be performed only before each drug administration for the first 3-4 months, and then every 6-8 weeks (Cancer Immunol Immunother. 2023 Jul;72(7):1991-2001). Other tests, such as coagulation, are recommended at baseline and every 3-6 months, while some others (e.g., lipase or amylase) are not recommended for routine use.
A single full blood examination leads to the emission of the equivalent of 116 g CO2 meaning that prescribing 1,000 tests equal to traveling 770 km by car (Med J Aust. 2020 Nov;213(10):477-477.e1). Similarly, it has been calculated that a coagulation test and urea and basic electrolytes testing produce emissions of 82 g CO2 and 99 g CO2 respectively. The carbon footprint of a single lab test can have a massive impact on the environment when scaling it up to a global scale, where thousands of people routinely undergo testing at any step of their oncology journey.
Despite oncologists might not be in a position to resize the climate impact of the whole healthcare system, we can embrace some actions toward a zero-emission oncology. It does not cost as much – a grounded commitment against climate change and, more practically, thinking of where to dispose gloves after patient examination, or which lab tests are strictly inevitable for delivering high quality care. With those small actions, we can be frontrunners of change in our departments and communities.