FOR TOXIC EFFECTS OTHER THAN CANCER

Subpart 1. Scope. This part establishes the method for determining a health risk limit for a toxic effect other than cancer. Subp. 2. Equation for toxic effects other than cancer or MCL-based HRLs. The equation for deriving a health risk limit for a toxic effect other than cancer or a maximum contaminant level-based health risk limit is: RfD duration x RSC x 1,000 nHRL duration = _ IR duration Where: A. nHRL duration is the noncancer health risk limit for a given duration as defined in part 4717.7820 , subparts 9, item A, and 13, expressed as µg/L. The HRLs derived for each chemical are listed in part 4717.7860 . B. RfD duration is the reference dose for a given duration as defined in part 4717.7820 , subparts 9, item A, and 21, expressed as mg/kg-day. The RfDs utilized for each chemical are listed in part 4717.7860 . C. RSC is the relative source contribution factor as defined in part 4717.7820 , subpart 22. The RSCs utilized for each chemical are listed in part 4717.7860 . D. 1,000 is a factor used to convert milligrams (mg) to micrograms (µg). There are 1,000 micrograms per milligram. E. IR duration is the intake rate for a given duration as defined in part 4717.7820 , subparts 9, item A, and 14. The IRs utilized for each chemical are listed in part 4717.7860 .