A review of available sources identified the following: multiple acute toxicity data (LD50, LC50) 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 LC50 was evaluated as a TEEL source, however it was determined inappropriate for TEEL development because no deaths were reported (see ECHA record). Instead, a 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 (316 mg/kg)
This review generated TEEL values inconsistent with Rev. 29A. The Rev. 29A TEEL-3 basis was a mouse oral LD50; instead, the current TEEL-3 is a more preferred species (rat > mouse) of the same route (oral) and type (LD50). The Rev. 29A TEEL-2 basis was a rat TDLo not found during the review. The Rev. 29A and current TEEL-1 used the same methodology (Table 3.5), with differences due to the change in TEEL-2.