A review of available sources identified the following: human LDLo (oral, skin) and animal acute toxicity data (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 human LDLo data was determined inappropriate for TEEL development because 1) one source did not indicate the sex, and 2) the other source was a non-standard deliver route (subcutaneous, Section 3.3.2). Instead, a dog oral LDLo 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 = Dog oral LDLo (25 mg/kg)
This review generated TEEL values that are inconsistent with Rev. 29A. The Rev. 29A values were based on a human oral LDLo; this source was found during the review, but the record was determined incomplete because the sex could not be confirmed (Section 3.3.1). Instead, analysts selected a dog oral LDLo as the TEEL-3 basis. The Rev. 29A TEEL-2 basis, a rat oral TDLo, was not found during this review; instead, the TEEL-2 was derived according to Table 3.5. The Rev. 29A and current TEEL-1 values were derived using the same methodology (Table 3.5), with differences due to the change in TEEL-2.