A review of available sources identified an LOC and acute toxicity data (LD50) for several species and routes. Reported GHS health hazard ratings (H315 and H319, Category 2; H301 and H335, Category 3) indicate a mid-to-high level health hazard. 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 toxicity data, a rat oral LD50, was selected as the TEEL-3 basis. The LOC was evaluated, but it resulted in a TEEL-2 > TEEL-3. Instead, 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 (107 mg/kg)
This review generated PAC values inconsistent with Rev. 29A. The Rev. 29A TEEL-3 basis was dog oral LD50 not found during the current review. The current TEEL-3 basis is a rat oral LD50. The Rev. 29A TEEL-2 was the LOC, while the current TEEL-2 was derived from the TEEL-3. The Rev. 29A and current TEEL-1 use the same methodology, with differences due to the change in TEEL-2.