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Download Effects Screening Levels (ESLs) Used in the Review of Air Permitting Data

Download previous effects screening levels (ESL) lists and current ESLs used in the review of air permitting data, and sign up to receive ESL-related announcements.

If you cannot find a listing for a particular constituent, this does not mean a health effects review is not required. A default short-term ESL of 2 µg/m3 can be used, or you may contact the Toxicology Division to determine if a screening level has been established for a constituent that is not listed in the database. If no screening level exists for the constituent, then all customers must complete the TCEQ Effects Screening Level Derivation Request Form Microsoft Excel Document and submit it to the Toxicology Division staff.

In the interest of time and resources, the Toxicology Division requests that you please conduct a thorough search of the TCEQ Toxicity Factor Database with CAS numbers and synonyms of the constituent of interest prior to contacting the Toxicology Division. If a request has been received with constituents that are listed in the TCEQ Toxicity Factor database, it will be returned.

The Toxicology Division processes ESL requests as quickly as possible, but ESL requests for long lists of chemicals may take up to a month to complete. Please contact us as early as possible in the permitting process to make requests.

Questions regarding ESLs

Technical questions regarding ESLs should be addressed to Stanley Aniagu at

About the TCEQ Toxicity Factor Database

The Toxicity Factor Database is now a part of Texas Air Monitoring Information System (TAMIS) database. This database is a one-stop-shop for information about all toxicity factors developed by the TCEQ. If you previously used Excel spreadsheets to access the toxicity factors, you will now access them via the TAMIS database. The TAMIS database includes not only Effects Screening Levels (ESLs), but also Air Monitoring Comparison Values (AMCVs) and their supporting documentation. The TCEQ created the database in order to reduce errors, improve database structure, provide more information and detail to our customers, and allow more dynamic and efficient data entry.

Learn more about the Toxicity Factor Database and query the Toxicity Factor Database to search for AMCVs.

Special Notations for the Toxicity Factor Database ESLs

This interoffice memorandum provides important information (notations and exceptions) to users on use of ESLs in air permitting. Exceptions provided in the document include how to evaluate a compound designated with PM, as well as exceptions to the 1-hr averaging period. This memorandum was previously provided with the ESL Published Lists under the Cover Memo tab. With the new Toxicity Factor Database, this memorandum will now be housed here for reference.