The Toxic Substances Act Chemical Substances Inventory: Reissued Inventory lists names for more than 50,000 chemical substances. This is the second file which is an index to the first by way of synonymous chemical names. Its entries are ordered alphabetically by name with the entries containing the same information as the Preferred Name File. The names included in the file are those valid names reported by submitters and the preferred CA Index Names. Because of possible ambiguities in nomenclature, the user should obtain and review the preferred CA Index Name in the Preferred Name File using the CAS Registry Number associated with the synonym concerned. This will not be necessary, however, in those cases where the name has an associated Name Code (e.g., 9CI) which signifies a preferred CA Index Name. The workunits in the file are in chemical name order. The order is not based on the EBCDIC form of the name, but rather a sortkey generated by a complex algorithm which queries various portions of the chemical name. Consequently, the file does not have a data element that identifies the sort order of the chemical names. However, for each physical file, the Sequence Number (data element 0012 01) can serve to identify the proper sequence of the names. The number is in ascending order having been generated during computer processing of the file. Each workunit of data can contain the following data elements: Molecular Formula, CAS Registry Number, Sequence Number, Preferred CA Index Name, Name Codes, UVCB Flag, Submitter Substance Name (reported), Chemical Substance Definition and EPA Flags. The file, with the TSCA Plantside Information, Production Information, and Preferred Name files, provides the complete Toxic Substances Control Act Inventory.