A review of available sources identified acute toxicity data (LD50) for several species and routes. 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 species and route data, a rat oral LD50, was selected as the TEEL-3 basis. TEEL-2 and TEEL-1 values were derived according to Table 3.5
• PAC-1 = TEEL-1 = TEEL-2/11
• PAC-2 = TEEL-2 = TEEL-3/6
• PAC-3 = TEEL-3 = Rat oral LD50 (3311 mg/kg)
This review generated PAC-3 and PAC-1 values inconsistent with Rev. 29A, and a consistent PAC-2 value. The Rev. 29A and current TEEL-3 and TEEL-2 sources, and methodologies are consistent; therefore, the minor difference in the TEEL-3 value may be due to rounding. The Rev. 29A TEEL-1 basis was a REL-TWA for soluble aluminum (CASRN: 7429-90-5) that is not in effect (see reference below). Instead, the current TEEL-1 was derived from the TEEL-2 (Table 3.5).