Health Hazard Evaluation Report HETA 84-006-1639; First National Bank Chicago, Illinois [open pdf - 5MB]
"On September 28, 1983, the National Institute for Occupational Safety and Health (NIOSH) was contacted by the Chicago Fire Department, requesting technical assistance concerning potential toxic effects of a fire then in progress in a Commonwealth Edison transformer vault beneath the First National Bank Building, Chicago, Illinois. The fire resulted in the loss of 15 gallons of oil, composed of 65% Polychlorinated Biphenyls (PCB - Arochlor 1260), and 35% trichlorobenzene, from one of four transformers in the vault. During the next 24 hours representatives from the utility company and the Illinois Environmental Protection Agency collected environmental wipe samples, air samples, and air filters from the ventilation system to determine the areas of PCB contamination. NIOSH investigators interviewed and drew blood samples for PCB, Polychlorinated Dibenzofurans (PCDF), and Polychlorinated Dibenzodioxins (PCDD) analysis from 2 firefighters who were hospitalized for smoke inhalation after a 15 minute exposure, and 2 maintenance workers who were in areas adjacent to the vault for 3 and 12 hours following the fire. None of these exposed individuals wore respiratory protection at that time. [...] Based on the results, of this study it has been determined that a potential health hazard existed due to exposure to PCB, PCDD, and PCDF at this Chicago transformer fire. Despite this potential, no absorption of PCB, PCDF, nor PCDD could be detected in the blood of four exposed individuals."
HETA # 84-006-1639; Health Evaluation and Technical Assistance Report Number 84-006-1639
Centers for Disease Control and Prevention: https://www.cdc.gov/