|10 min||30 min||1 h||4 h||8 h|
|1,100 ppm (5,170 mg/m3)||800 ppm (3,760 mg/m3)||400 ppm (1,880 mg/m3)||400 ppm (1,880 mg/m3)||400 ppm (1,880 mg/m3)|
|(Final Report) with Cover Letter Dated 102291. Submitted by Shell Oil Company to U.S. Environmental Protection Agency, Washington, DC. EPA Document No.
TSCATS 88-920000156. Microfiche No. OTS 0534605
|Test species/Strain/Number: Rats and guinea pigs, strains unknown, five per sex per species.|
|Exposure route/Concentrations/Durations: Inhalation, 2,990, 5,850, or 7,970 ppm for 30 min; 14-day observation.|
2,990 ppm: Slight ocular and nasal irritation
5,850 ppm: Narcosis and impaired ability to escape
7,970 ppm: No deaths; ataxia and narcosis
|End point/Concentration/Rationale: No deaths after 30-min exposure at 7,970 ppm.|
Total uncertainty factor: 10 (a larger factor would lead to AEGL-3 values that would conflict with AEGL-2 values)
Interspecies: 3, data were comparable for rats and guinea pigs suggesting no large interspecies differences, and the critical effect is CNS depression.
Intraspecies: 3, interindividual variability for CNS depression by comparable gases generally will not be greater than a factor of 2 or 3.
|Modifying factor: None|
|Animal-to-human dosimetric adjustment: None|
|Time scaling: Cn × t = k; default values of n = 3 for 10-min value and n = 1 for 1-h value. AEGL-3 values for 4-and 8-h are set equal to the 1-h value because chlorobenzene concentrations in blood reach a steady-state within 1 h and its elimination is rapid. Furthermore, time scaling would result in 4-and 8-h
AEGL-3 values that would conflict with AEGL-2 values and human data.
|Data adequacy: Sufficient|