[Toxicological examination of new chemicals].

The authors consider the problem of the express study of new or scantily studied chemical compounds. The data received in short-term experiments allow not only to validate hygienic standards but also to evaluate the character of action of chemicals studied. The authors discuss the possibility of rejecting the determination of Lim(ac) in practice of validating Tentative Safe Exposure Levels in working zone air (TSELwz).