A review of available sources identified acute toxicity data (LCLo, LD50, LDLo¬) 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 route toxicity data, a mouse LCLo, was selected as the TEEL-3 basis and it was scaled to 60-minute equivalent using the ten Berge equation (Section 3.3.4). 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 = Mouse LCLo (1095 ppm/18H)
This review generated PAC-2 and PAC-1 values consistent with Rev. 29A and a PAC-3 ppm value inconsistent with Rev. 29A. The Rev. 29A and current TEEL-3 source, an 18-hour mouse LCLo, and methodology are consistent; as such, the minor difference in the reported ppm values may be due to rounding.