I've researched this recently. Thermal decomposition of Vinyl Chloride Monomer forms HCl, CO, CO2, and trace phosgene. Thermal decomposition of literally all

I've researched this recently. Thermal decomposition of Vinyl Chloride Monomer forms HCl, CO, CO2, and trace phosgene. Thermal decomposition of literally all the other chemicals listed produces CO and CO2. It's likely that a certain number of animal deaths in the area have been caused by HCl being absorbed by water (in lungs) and forming acid, or CO/CO2 displacing oxygen and suffocating them. As far as I have found, none of the chemicals spilled is toxic to marine life. Dead fish could be coming from soot or other pollutants from the fire rather than from the chemicals.... hard to say. By the way, VCM has a half life of about 20 hours in the atmosphere.