剧毒化学品甲苯-2，4-二异氰酸酯运输危险性评估

为探讨低挥发性剧毒化学品甲苯-2，4-二异氰酸酯在运输过程中大量泄漏引起群体中毒事故的可能性以及对环境的影响，对本品的急性毒性、扩散模型、环境转归、生态毒性，以及运输泄漏事故资料进行综合分析和评估。评估结果本品吸人中毒的潜在危险性指数为低度危险物质；扩散模型运输泄漏模拟危险区域下风向距离小于某些非剧毒品；环境转归研究显示本品在环境介质中没有持久性，没有明显的生物蓄积性，生态毒性较低；历年来运输泄漏事故分析未见发生大规模严重群体中毒和环境污染事故。认为本品在运输过程中大量泄漏，不会大范围扩散引起严重群体中毒事故，也不会对环境造成严重和长期的危害，建议在运输环节中运输条件适当放宽，按照一般有毒品进行管理。

The hazard assessment during the transportation of toluene-2,4-diisocyanate as a high toxicity chemical

In order to study the possibility of poisoning in population due to a spill of toluene -2,4 -diisocyanate （2,4 -TDI） as a high toxicity low-volatile chemicals during transportation and its effect on environment, the acute toxicity, diffusion model, fate in environment, ecotoxicity, and accidents during transportation of 2,4 -TDI were integrately analysed and assessed to provide the agents for transportation of high toxicity chemicals with references. The study concluded that the index of potential inhalation toxicity （IPIT） of 2,4 -TDI showed a low hazardous substance （ Class Ⅳ ）, that the size of hazardous zone in downwind direction modeled in a diffuse model was lower than that of non-high toxicity products. The fate in environment did not indicate any persistent in environment and obvious bio-accumulative. It also showed low bio-toxicity. Any large scale severe poisoning in population and any environment pollution were not found in accidents during transportation in past years, Therefore it was thought that the spill of 2,4 -TDIs during transportation would not lead to any severe poisoning in population due to diffuse in wide scope and to any sever long-time environment hazard. It was suggested that the conditions during 2,4 - TDI transportation should be properly released and it should be taken as a common toxicity substance.