Estimating the Carbon Emissions of a Single Prostate-specific Antigen Test: Results from a Cradle-to-grave Life Cycle Assessment.

Background and objective: The health care sector is a significant contributor to greenhouse gas (GHG) emissions, and assessments of the environmental impacts of health services are essential. We aimed to evaluate the environmental impact of a highly common but controversial urology-specific blood test: the prostate-specific antigen (PSA) test.

Methods: A cradle-to-grave life cycle assessment was performed to estimate the emissions of a single PSA test. Primary data collection included laboratory site assessment, disassembly, and weighing of materials. The primary outcome was GHG emissions in grams of carbon dioxide equivalent (CO₂e). The secondary outcome was the health impact attributed to the environmental harm of the test.

Key findings and limitations: A single PSA test generates an estimated total of 189.7 g of CO₂e. The majority of emissions (88.2%) were generated by the raw materials, manufacturing, production, and disposal of the blood draw equipment. Annual CO₂e emissions from PSA testing in the USA were estimated at 5 691 000 kg CO₂e, equivalent to driving 14.5 million miles, with a resulting human health impact of 6.6 disability-adjusted life years annually. This study focused on the PSA test itself, and not on emissions from staff, patient, or sample transportation; building infrastructure; or cleaning.

Conclusions and clinical implications: Although the carbon footprint of a single PSA test is small, the cumulative impact of the estimated total of 30 million PSA tests performed annually in the USA is substantial, especially when considering that a notable proportion of these tests may be performed on men who are unlikely to benefit.