BACKGROUND: In the last decade, environmental impact assessment has become a major concern for human activities, which is particularly true for health. The french healthcare sector emits approximately 49 million tons of CO METHODS: A retrospective study was conducted in a french CPU producing more than 51,000 preparations per year in 2022. Global warming impact of CO RESULTS: The carbon footprint of the CPU was equal to 18'230.7 tons of CO CONCLUSION: This study prompts us to identify the main sources of GHG emissions within a CPU. Areas for improvement to reduce global warming impact might be deprescribing of antineoplastic drugs, staff transport reduction using telecommuting or carpooling and rethinking our production process to reduce waste production.