Sources of Variation in the Carbon Footprint of Hemodialysis Treatment

Abstract

Background: Greenhouse gas emissions from hemodialysis treatment in the United States have not been quantified. In addition, no previous studies have examined how much emissions vary across facilities, treatments, and emission contributors.

Methods: To estimate the magnitude and sources of variation in the carbon footprint of hemodialysis treatment, we estimated life-cycle greenhouse gas emissions in carbon dioxide equivalents (CO₂-eq) associated with 209,481 hemodialysis treatments in 2020 at 15 Ohio hemodialysis facilities belonging to the same organization. We considered emissions from electricity, natural gas, water, and supply use; patient and staff travel distance; and biohazard and landfill waste.

Results: Annual emissions per facility averaged 769,374 kg CO₂-eq (95% CI, 709,388 to 848,180 kg CO₂-eq). The three largest contributors to total emissions were patient and staff transportation (28.3%), electricity (27.4%), and natural gas (15.2%). Emissions per treatment were 58.9 kg CO₂-eq, with a three-fold variation across facilities. The contributors with the largest variation in emissions per treatment were transportation, natural gas, and water (coefficients of variation, 62.5%, 42.4%, and 37.7%, respectively). The annual emissions per hemodialysis facility are equivalent to emissions from the annual energy use in 93 homes; emissions per treatment are equivalent to driving an average automobile for 238 km (149 miles).

Conclusions: Similar medical treatments provided in a single geographic region by facilities that are part of the same organization may be expected to have small variations in the determinants of greenhouse gas emissions. However, we found substantial variation in carbon footprints across facilities, treatments, and emission contributors. Understanding the magnitude and variation in greenhouse gas emissions may help identify measures to reduce the environmental effect of hemodialysis treatment.

Keywords: carbon footprint; hemodialysis.

Graphical abstract

Figure 1.

Contributors to carbon footprint of hemodialysis (n=15 facilities). The y axis indicates magnitude of emissions per treatment, with error bars representing upper and lower CIs. For example, electricity use is associated with 15.7 kg CO₂-eq emissions per treatment (CI, 12.1 to 20.4 kg CO₂-eq). The x axis indicates variation across facilities. For example, natural gas use is associated with a 42.4% coefficient of variation in emissions per treatment across the 15 facilities. Other contributors with either a high magnitude of emissions or extensive variation across facilities include landfill waste, water, and transportation. By contrast, supply use and biohazard waste have lower magnitudes and variation.