A review of available sources identified 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 most preferred route and species toxicity data, a rat LC50, was selected as the TEEL-3 basis and was scaled to a 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.
• TEEL-1 = TEEL-2/11
• TEEL-2 = TEEL-3/6
• TEEL-3 = Rat LC50 (70810 mg/m3/4H)
This review generated TEEL values inconsistent with Rev. 29A. The Rev. 29A TEEL-3 basis was a molecular weight adjusted IDLH for fluorides, while the current basis is acute inhalation data for benzotrifluoride. The Rev. 29A TEEL-2 basis was a rabbit TCLo ¬not found during the review; instead, the current TEEL-2 was derived from the TEEL-3 (Table 3.5). The Rev. 29A TEEL-1 basis was molecular weight adjusted TLV-TWA for fluorides; analysts found that this compound is classified as a fluorinated organic compound, not as a fluoride. As such, the current TEEL-1 was derived from the TEEL-2 (Table 3.5).