When reporting started in 1978 for the Chemical Substance Inventory of the Toxic Substances Control Act (TSCA) the process was structured so that companies were encouraged to report as many products and corresponding CAS numbers that qualified under the rules. To comply, manufacturers had to report production or importation of chemicals in excess of 10,000 pounds per year. Although the regulations clearly identified amounts that had to be reported, little was said about product definition and identity. Accurate product definition is important in reporting of products derived from lignins as many are polymers and fall into a category exempt from the reporting requirements.

To complicate the situation, in the previous 50 years or so, a real hodge podge of names and CAS numbers had been developed which fit various concepts of commercial lignin products. A major cause for this diversification was that commercial lignin products are complex mixtures (some components unknown) of organic polymers, dimers and monomers. In fact the exact chemical structure of lignin is still unknown. The result was 77 entries in the 1985 Edition of The Chemical Substances Inventory for commercial lignin products. Many lignin products could be legitimately designated by two or more names and corresponding CAS numbers resulting in miscommunication and confusion.

In 1995, the Lignin Institute (LI) adopted a nomenclature convention designed to end the confusion. LI Proposed:

• Terms such as spent sulfite liquor, spent pulping liquor, spent liquor will be used only for dilute raw material as it leaves the pulp mill.
• Specific lignin products are to be called (cation) lignosulfonates, lignin sulfonates or lignosulfonic acid (cation) salt. These terms are defined as being synonymous with the preferred term being (cation) lignosulfonate.