Substances can have many synonyms. While a substance may have a record in the Substance Registry System (SRS), all the synonyms for that substance may not be in SRS. So searching for a synonym that is not available in SRS will not produce any results. If you know the Chemical Abstract Service (CAS) number for the chemical or the Taxonomic Serial Number for the biological organism, you can search SRS using those criteria. Alternatively, you could search the Internet using your synonym to discover other synonyms with which you could search SRS.
If you discover a synonym that is not in SRS, but should be, please submit that change in the Contact Us link.
To access SRS go to: www.epa.gov/srs