Substance Priority List (SPL) Resource Page

This web page provides supporting information regarding the development of the Substance Priority List, as well as expanded information on current and past lists.

Support Document to the 2022 Substance Priority List [PDF – 325 KB] – Describes the methodology used to generate the Substance Priority List.

ATSDR 2022 Full SPL Spreadsheet [ZIP – 5.0 MB] – A zip file containing a Microsoft Excel spreadsheet of all SPL and CEP Reports with details for every element of their algorithms, additional supporting information, and a PDF of cover notes for using the data. This spreadsheet has data from all past Lists, including information for all available candidates (past the top 275 substances for the SPL and 100 for the CEP Report). It includes concentration statistics for major media, data which is not readily available anywhere else. Also includes summary statistics to put the dataset as a whole into perspective. See the spreadsheet’s Cover Notes PDF (in the zip file) for more information.

SPL Toxicity Values [XLS – 73 KB] – A spreadsheet of the Reportable Quantities (RQs) and Toxicity/Environmental Scores (TESs) used for the SPL.

Methodology for Toxicity/Environmental Scores [PDF – 238 KB] – Describes the methodology used to determine the Toxicity/Environmental Scores (TESs) for the Substance Priority List.

SPL Dates and Notices [PDF – 146 KB] – A table of run, release, and Federal Register Notice dates and links, for current and past SPLs. Includes a short historical overview of the List.

Contact Information

Further information can be obtained by contacting the ATSDR Information Center at:

Agency for Toxic Substances and Disease Registry
Division of Toxicology and Human Health Sciences
1600 Clifton Road NE, Mailstop S102-1
Atlanta, GA 30329
Phone: 1-800-CDC-INFO 888-232-6348 (TTY)
Email: Contact CDC-INFO


Persons with disabilities experiencing problems accessing this page can contact CDC-INFO by using the form at, by calling (800)232-4636, or via the TTY number (888)232-6348. Ask for 508 Accommodation PR#71. If using the form, please type “508 Accommodation PR#71” (without quotes) and the URL of this page in the Subject line.