A review of available data sources identified the following: LD50 (dog1, mouse2, and rat3-5) and LC506 exposures for inhalation, intravenous, intraperitoneal, and oral routes. A duration of 240 minutes was assumed for the ten Berge time-scaling of the LC50 (Section 3.3.4). Where unspecified, a duration of 1 day was assumed for other routes.
Toxicity data were evaluated for their relative preference ranking (Section 3.3.2, Table 3.1). Although the LC50 was the most preferred, it was the oldest toxicity data and listed no time for the exposure. Due to the uncertainty this introduced to an otherwise preferred method, this data was not used. Instead, a dog intravenous LD50 was selected as a starting point for a TEEL-3 estimate because it was the most recent and had a more reputable source. TEEL-2 and TEEL-1 values were calculated from the TEEL-3 value, according to Table 3.5.
• TEEL-1 = TEEL-2/11
• TEEL-2 = TEEL-3/6
• TEEL-3 = Estimated from dog, intravenous LD50 (3000 mg/kg)
This review generated TEEL values consistent with those published in Rev. 29A.