| Popis: |
The single-dose intraperitoneal LD50, meq/kg, of the chlorinated pyridines in mice is as follows: 2,6-dichloro-, 0.78; 2,3,6-trichloro-, 0.82; 2,3-dichloro-, 0.91; 2,3,4,5,6-pentachloro-, 0.94; 2-chloro-, 1.14; 2,4,6-trichloro-, 1.54; 2,3,4,5-tetrachloro-, 1.96; 3-chloro-, 2.05; 2,3,5-trichloro-, 2.36; 4-chloro-, 2.46; 2,3,5,6-tetrachloro-, 5.30; 3,5-dichloro-, 7.98; and 2,5-dichloro-, 11.42. 2-Chloropyridine is somewhat more toxic to mice when given orally than when given by intraperitoneal injection. Concurrent administration of methionine but not cysteine to mice has a protective effect against the toxicity of 2-chloropyridine while nicotinamide augments the toxicity. In studies using rabbits, 2-chloropyridine was essentially as toxic when applied to the skin as when given by intraperitoneal injection. The single-dose inhalation toxicity of 2-chloropyridine was determined using rats. Following vapor exposure, histopathologic examinations revealed that this compound caused central lobular necrosis, hemorrhage, and fatty degeneration as well as cellular infiltration. Maximum single-dose exposures not causing these changes were 100 ppm for 3 minutes, 50 ppm for 6 minutes, 25 ppm for 12 minutes, and 10 ppm for 30 minutes. Maximum single-dose exposures that did not cause death were 1000 ppm for 6 minutes, 500 ppm for 12 minutes, 250 ppm for 30 minutes, 100 ppm for 2 hours, and 50 ppm for 4 hours. |
