Travel-associated carbon emissions of patients receiving cancer treatment from an urban safety net hospital.

e13812 Background: Climate change is one of the grand challenges of the 21 st century. The U.S. currently emits 11% of the annual global greenhouse gases, and 8-10% of its emissions result from the healthcare industry. Studies on the contribution of patients' commute for cancer treatment to healthcare-associated CO 2 emissions remain limited. This study aims to determine the CO 2 emissions of patients’ commute for cancer treatment among patients with malignancies at an urban safety net hospital. Methods: We conducted a retrospective study of patients seen at an oncology clinic from July 1, 2022 - June 30, 2023. Demographic data, data on visit diagnosis and indication (e.g., laboratory, infusion, or follow-up visits), and patients' home addresses were collected from the EMR. Distance between patients’ homes and the hospital was calculated using a Google Map API and a macro for distance. Total CO 2 emissions from patients’ travel in miles were estimated at 400 grams of CO 2 per mile based on the Environmental Protection Agency’s estimate of the average CO 2 emissions for a passenger vehicle. The primary outcome was CO 2 emissions from patients’ round-trip travel. The total estimated CO 2 emissions were converted to equivalents of coal burned, smartphones charged, and gallons of gasoline used based on the EPA equivalencies calculator. Results: Of the 8,235 visits, 5,095 (61.8%) were follow-up/laboratory visits, and 3,137 (38.1%) were chemotherapy infusion visits. Of the 1,080 patients who attended the clinic, the mean age was 63.8 years, 700 (64.8%) were males, 379 (35.1%) were females, 525 (48.6%) were black or African American, 139 (12.9%) were whites. Breast cancer was the most common diagnosis, with 423 (39.2%) of patients. Each patient traveled an average of 9.6 miles round trip (Range = 0.7-298.6 miles) to receive cancer care. An estimated 1,520 grams of CO 2 was emitted for each patient’s visit. A total of 79,582 round trip miles was made in 8,235 visits, which corresponds to 31,832 kg of CO 2 emissions, equivalent to 35,658 pounds of coal burned, 1,462 propane cylinders used for a home, or 3,872,250 smartphones charged. Conclusions: Cancer care is associated with significant CO 2 emissions. Efforts to decrease the overall carbon footprint of cancer treatment through adoption of telemedicine and alternative treatment schedules, are needed to reduce the effect of cancer treatment on the climate. [Table: see text]