A review of available sources identified limited acute toxicity data for 3-(cyclohexylamino)-1-propanesulfonic acid. Reported GHS health hazard ratings (H315 and H319, Category 2; H335, inhalation Category 3) indicate a mid-level health hazard, approximately equivalent to an HHR=2. The reported rat oral LD50 (2000 mg/kg) did not report any signs of acute toxicity or mortality, therefore it was not selected for TEEL development. Considering this, and the GHS health hazard codes, analysts assumed an HHR=2 as the TEEL-3 basis (Section 3.4.5). 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 = HHR=2
This review generated PAC values that are inconsistent with Rev. 29A. The Rev. 29A TEEL-3 basis was a rat oral LD50 that was evaluated during this review, that was determined to have no reported toxicity; instead, the current TEEL-3 basis is an assumed HHR=2, from analysis of GHS health hazard statements. The Rev. 29A and current TEEL-2 and TEEL-1 use the same methodology, with differences due to the change in TEEL-3.