Cradle-to-Gate Greenhouse Gas Emissions for Twenty Anesthetic Active Pharmaceutical Ingredients Based on Process Scale-Up and Process Design Calculations

Comparative life-cycle assessment (LCA) of pharmaceutical drugs would enable clinicians to choose alternatives with lower environmental impact from options offering equivalent efficacies and comparable costs. However, life-cycle inventory (LCI) data of individual pharmaceutical drugs is limited to only a few compounds. In this study, we use chemical engineering methods for process scale-up and process design to utilize lab-scale synthesis data, available in patents and other public literature, to generate cradle-to-gate LCI data of 20 commonly used injectable drugs in anesthesia care to calculate their greenhouse gas impact. During the process of building the life-cycle trees of these drugs, missing life-cycle inventories for more than 130 other chemical compounds and pharmaceutical intermediates were accounted for using process based methods and stoichiometric calculations. The cradle-to-gate GHG emissions of the 20 anesthetic drugs range from 11 kg CO2 eq. for succinylcholine to 3,000 kg CO2 eq. for dexmedetomidine. GHG emissions are positively correlated with the number of synthesis steps in the manufacturing of the drug. The LCI methods and data generated in this work greatly expand the available environmental data on APIs and can serve as a guide for LCA practitioners in future analysis of other pharmaceutical drugs. Most importantly, these LCA results can be used by clinical practitioners and administrators building toward sustainability in the health care sector.