Review of quantitative assessment methods on fire smoke toxicity
TONG Zhao-yang, YIN Yi-feng, HUANG Qi-bin, LIN Fu-sheng(The Fourth Department, Beijing Pharmacological Chemistry Institute, Beijing 102205, China)
This article is aimed at presenting the authors' review of the quantitative approach to the assessment of toxic potency on smoking fire for it is a newly developed field of combustion toxicology. Some toxic gases from the fire are material-dependent while others rely on the actual combustion conditions, still some others may be dependent on both of them. However, all the ways of fire smoking diffusion in the room condition and during the exposure time are closely related to the nature of the fire smoke toxicity. Therefore, it is difficult to accurately predict the complicated components of fire smoke toxicity in traditional ways for toxicity analysis. To change the situation, most researchers nowadays prefer to give quantitative assessment based on the development of the mathematically simulated models, trying to make systematic account for and predict the practical features of the smoking fire toxicity in particular cases and minimize the needs of the experimental animals to be tested. In our research, we have developed \%N\%-gas, FED and TGAS Models to get smoke toxicity data for fire hazard analysis. The so-called \%N\%-gas Model is used to assess the toxicity of complex fire gas mixture based on a database of experimental results of individual and mixed gases including CO, CO_2, reduced O_2, HCN, HCl, HBr and NO_ \%x\%. The assessment is then checked with a small number of testing animals and a rough value of LC_ 50 will then be determined. The FED Model relies on the concept of the Fractional Effective Dose (FED) for asphyxiant gases and the Fractional Effective Concentration (FEC) for irritant gases. The effects of asphyxiants and irritants can then be assessed separately. Although FED values and FEC values are all additive with each other, they cannot be combined. TGAS Model can only provide an estimate of the probability of immediate incapacitation from internal dose normalized by the body mass that allows extrapolation from small animals to human beings, which could be used to assess incapacitation risk in human subjects from toxic gas inhalation. The model assessments prove to be well matched with animal incapacitation analysis both for single and combined gases. And, finally, the paper has also made a detailed discussion on the application ranges, advantages and advantages of the above models, which may be useful for further research on the developmental trend of quantitative assessment on fire smoking toxicity in the future.
【CateGory Index】： R114
【CateGory Index】： R114