Our findings showed that ibuprofen and acetaminophen significantly increased mutation frequency and conferred high-level ciprofloxacin resistance. Whole-genome sequencing identified mutations in GyrA, MarR, and AcrR, with the latter two correlated with overexpression of AcrAB-TolC drug efflux pump. Co-exposure to two NAMs further elevated mutation rates and ciprofloxacin resistance levels.
