Updated project metadata. We carried out a prospective, longitudinal, single-center, observational cohort study of patients with confirmed acute methanol poisoning that were treated in hospitals during a mass methanol poisoning outbreak in the Czech Republic in 2012. Venous blood for proteomic analysis was obtained from 24 patients with confirmed acute methanol poisoning upon admission to the hospital (group M (“Methanol”)) with heparin administration for hemodialysis and ethanol or fomepizole administration as the antidote to block ADH. In the follow-up group of survivors of methanol poisoning (group S (“Survivors”)), venous blood samples for proteomic analysis were obtained from 46 patients during the examination, which took place 4 years after discharge from the hospital. For the control group not exposed to methanol, 24 healthy subjects were recruited (group C, “Controls”). Blood samples were spun, the serum was separated, and the samples were frozen to −80 °C until the analyses. Blood serum samples were depleted of most abundant serum proteins using Agilent MARS 14 column, samples fractionated and fractions containing proteins of interest precipitated. Samples were analyzed using LC-MS/MS Thermo Orbitrap Fusion (UHPLC-ESI-Q-OT-qIT) and identified proteins with differential expression.