ASSESSMENT OF TOXIC GASES GENERATED BY FIRES POLYMERS

FERRARI, L AND GIANNUZZI L

Buenos Aires

Congreso; 52th Annual Meeting International Association of Forensic Toxicologis (TIAFT).; 2014

TIAFT

Introduction: In previous work we analyze two episodes of polyurethane foam fires in prison units of Argentina. There is debate about the physical and chemical factors that cause death. In these cases it is detected in the blood of 33 victims, carbon monoxide (CO) and hydrogen cyanide (HCN), but with different concentrations. Few investigations have focused on physical factors such as: temperature generated, burning rate of the polymer, other gases simultaneously originated, combustion room dimension and calculation of lethal concentrations. This paper addresses an original method for evaluating these parameters and their correlation with data from blood of the victims. Methods: In California 117 chambers, 12.1 g of sinister polymer was used in pieces of 300 mm x 72 mm x 13mm. Then, the combustion with a burner (10 sec) was started. The combustion time was calculated at the opposite end to 30 cm. It was compared with mattresses within ignition inhibitors. EMMA XILIX 2001 was analyzed with validated sensors: CO, O2, CO2, NOx, HC and SO2 and temperature (T) with digital thermometer. Blood of 33 fatalities were processed by Co-oximetry to MetHb and CO. Validated microdiffusion method for HCN was used. Result: propagation speed: 109 mm / min. Total consumption of the polymer: 3 min. O2 (initial: 21%) decreased to 11%; CO increased to 4000 ppm. HC: 574 ppm; SO2: 698 ppm; NOx: 102 ppm; CO2: 4.32%. The T of the gases in the chamber reached 102°C. HCN: greater than 250 ppm. In blood: HCN: 0.36 - 15 mg/L, HbCO: 30-42% and MetHb: 1.8-35% Conclusion: decreased oxygen and increased T might be important in the space where the fire originated. In addition, O2 levels shown for flight incapacitation. Increased NOx would explain increased MetHb blood of the victims. Other consequences were analyzed.