“…This scale assigns each medication a value of 0 (no impact) to 3 (severe impact) for each category (persistence, bioaccumulation, toxicity) and adds the values to determine the overall PBT score. Propofol has a value of 6 [32,39,40] due to its score of 3/3 for Persistence and 3/3 for Toxicity. The PBT scores for several medications used in anesthesia are available (fentanyl ¼ 4, remifentanil ¼ 4, ropivacaine ¼ 4, bupivacaine ¼ 5, midazolam ¼ 5), but data for many anesthesia agents are not available [39].…”