This edition of the Registry of Toxic Effects of Chemical Substances is the fourteenth edition prepared in compliance with the requirements of the Occupational Safety and Health Act of 1970. The Registry's purposes are many, and it may serve a variety of users. It is a single source document for basic toxicity information and for other data, such as chemical identifiers and information necessary for the preparation of safety directives and hazard evaluation for chemical substances. The various types of toxic effects linked to literature citations provide researchers and occupational health scientists with an introduction to the toxicological literature, making their own review of the toxic hazards of a substance easier. By presenting data on the lowest reported doses that produce effects by several routes of entry in various species, the Registry furnishes valuable information to those responsible for preparing safety data sheets for chemical substances in the workplace. Included in the Registry are the following types of data: Tumorigenesis, Mutagenesis, Reproductive Effects, Primary Irritation, and Human Toxic Effects. This edition of the Registry contains 88,693 prime chemical substances.