SRM traces for MeIQx, 8-CH2OH-IQx, and IQx-8-COOH in a urine sample collected before and after meat consumption. The transition employed to monitor 8-CH2OH-IQx and IQx-8-COOH, and their internal standards was 20 eV. The retention time (tR), area, and ion intensity are reported. The large peak eluting at tR 23.0 min and monitored with the transition 214.1 > 199.1 is 7-MeIgQx, an isomer of MeIQx, which elutes at tR 23.8 min.