多年来,毒理工作者一直对产生LD_(50)值的传统试验方法的科学依据和所涉及的伦理道德表示异议。同时,毒理学家们认为,将来仍需要继续研究各种物质的急性毒性,以获得毒作用性质、出现毒性体征的时间、以及从亚致死剂量恢复的大致百分率和恢复的程度等资料。因而迫切需要一个从科学和伦理道德上更易接受,并仍能提供危险度评价者和管理者所需资料的替代方法。为此,曾提出了各种供选择的方法,但由于这些方法未能减少动物数量,或仍以死亡作为终点或未经国际上的验证等原因未被接受。1984年,英国毒理协会(BTS) For many years, toxicologists have been opposed to the scientific basis and the ethics involved in the traditional test methods for producing LD_ (50) values. At the same time, toxicologists believe that in the future, the acute toxicity of various substances will still need to be studied in order to obtain information on the nature of toxic effects, the timing of toxicological signs, and the approximate percentage recovery from sublethal doses and the degree of recovery. There is an urgent need for an alternative that is more scientifically and ethically acceptable and still provides the information needed by risk assessors and managers. To this end, a variety of alternative methods have been proposed, but these methods have not been accepted due to the failure to reduce the number of animals or to death as an end point or without international verification. In 1984, the British Toxicology Association (BTS)