Use of alternative endpoints with the UPitt II method for assessing the toxicity of smoke.

A small-scale combustion module and animal exposure system for evaluating flaming combustion and toxicity of smoke from burning polymers has been developed at the University of Pittsburgh and designated the UPitt II method. It is a radical departure from previous attempts to evaluate toxicity of smoke from burning polymers and represents a significant improvement over previous systems because well-defined burning conditions can be established over a wide range of imposed heat flux and ventilation levels, not possible to examine with previous methods. Thus, smoke toxicity can be evaluated under a range of burning conditions and differences in toxic potency and time to effect can be evaluated. A potential smoke hazard (PSH) index was developed which integrates the material performance characteristics which determine ease of ignition of a polymer with toxic potency, time to death, and rate of generation of toxicants. This paper describes sublethal endpoints that can be used with the UPitt II method and modifications to the PSH index for evaluating the toxicity of smoke generated by burning polymers.