The following LSPA practice tip was introduced at the May 2026 Membership Meeting, which was held via Zoom on Thursday, May14, 2026, from 3:45-5:00 PM.

Practice Tip  
Chemical Abstract Service Registry Numbers (CAS RNs or CAS Numbers) are standardized numerical strings used to identify specific chemical substances. Chemicals may have multiple or varying names, spellings, trade names, etc.; however, the same substance will always have the same CAS Number. Given the importance of chemical identification, the tables and laboratory reports that are submitted in an MCP report should include chemical names along with applicable CAS Numbers. This will help avoid confusion as to what information or MCP standard is associated with a given chemical and will provide a direct link between a chemical and the MCP.

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