Air Toxics Screening Level Justifications

Contact: Doreen Lehner, 517-284-6753
Agency: Environment, Great Lakes, and Energy

The Air Quality Division (AQD) regulates sources of air pollutants to protect human health. Heath-based screening levels are utilized in AQD's Permit to Install (PTI) regulatory program for the assessment of toxic air contaminant (TAC) emissions.

Information on how these health-based screening levels were derived is contained in the AQD justification memos that can be accessed below.


Full List of Screening Levels & Justifications

They will be sorted by:



  • The list is updated every Monday morning (or the first workday after a Monday State holiday) by approx. 10:15 AM Eastern Time.
  • You can use your browser's search function to find a particular chemical. On most browsers, it will be in your menu, e.g. EDIT > FIND; or type CTRL+F.
  • If the "Send Comment" link in the PDF does not work for you, please manually open a new e-mail addressed to EGLE‑AQD‑ with the subject line "Air Toxics Screening Level Justifications for" with the chemical in question. Enter your comments in the body of the e-mail, then send it to us.
  • Documents that end in "RTC.pdf" are the Response to Comments.