Water Pollution and Environmental Concerns in Anesthesiology

Abstract

Medications administered by anesthesia health care providers and subsequently excreted into the water supply system have the potential to affect ecological systems. Presently, there is a lack of literature examining which medications or metabolites enter the waste stream. Further, their potential environmental impacts are often unknown or simply not considered as an externality of medical practice. Recent work examining the practice of anesthesiology has explored the solid waste stream, and the global warming potential of anesthetic gases, however the potential aquatic impacts remain unexplored. To address the potential for waterborne pollution and environmental toxicity, we extracted the total intravenous medications (by mass) administered by anesthesiologists in 2017 at The University of Vermont Medical Center (UVMMC), a mid-size regional Level 1 trauma center in Burlington, VT. The most commonly administered medications were: cefazolin, propofol, acetaminophen, sugammadex and lidocaine. To estimate the amount of each medication that entered the wastewater stream, we used published metabolism profiles to adjust from the total amount administered to the amount excreted unchanged or as prominent metabolites. For each medication we reviewed existing literature concerning their environmental fate and impacts in water. Due to the constraints of current knowledge, it is not possible to determine the exact fate and impacts of these drugs. Some medications, like propofol, have the potential for significant bioaccumulation and persistence. Others, such as lidocaine and acetaminophen, have short half-lives in the environment but their constant delivery and excretion result in pseudo-persistence. The current literature mostly assesses acute exposure at doses higher than could be expected in the environment on select species. While significant toxicities across a variety of species have been found repeatedly, chronic low dose exposures require further study for all the medications discussed. Finally, multi-drug impacts are likely to be more impactful than single-drug toxicities. While we cannot state definitive impacts, the pharmaceuticals most used in anesthesiology have a clear toxic potential and future studies should more closely examine the relative contribution of anesthesia to pharmaceutical pollution, as well as points of intervention for minimizing these unintended consequences of healthcare delivery.