A review of available sources identified rabbit and rat acute toxicity data (LD50). Data sources were selected according to the hierarchy listed in Table 3.1. Toxicity data were selected according to type of exposure, species, and route according to the hierarchies stated in Sections 3.3.1, 3.3.2, and evaluated using factors in Tables 3.2, 3.3, and 3.4. The most preferred route and species toxicity data, rat oral LD50, was selected as the TEEL-3 basis. TEEL-2 and TEEL-1 values were derived according to Table 3.5.
• TEEL-1 = TEEL-2/11
• TEEL-2 = TEEL-3/6
• TEEL-3 = Rat oral LD50 (735 mg/kg)
This review generated TEEL values inconsistent with Rev. 29A. The Rev. 29A and current TEEL-3 sources are consistent, a rat oral LD50; however, the toxicity dose used in Rev. 29A calculations was not found during this review. Instead, an available toxicity dose was used, resulting in a slightly higher, but comparable magnitude, TEEL-3 value. The Rev. 29A and current methodology used to derive TEEL-2 and TEEL-1 are consistent, with difference in values due to the change in TEEL-3.