Tissue levels of glutathione following acute inhalation of 1,3-dichloropropene.

Rats were exposed by inhalation to 1,3-dichloropropene (DCP) to assess the relationship between DCP exposure concentration and tissue levels of reduced glutathione (GSH). Animals were exposed for 1 h in a dynamic, nose-only system. GSH content, indicative of DCP metabolism, was measured in heart, kidney, liver, lung, nasal mucosa, and testes. A decrease in nasal GSH content was first seen at 5 ppm DCP and followed an exposure concentration-dependent curve. Exposure to concentrations above 305 ppm DCP reduced the level of liver GSH in an exposure concentration-dependent manner. Although depressed, lung GSH content remained relatively constant at approximately 75% of control following concentrations of up to 955 ppm DCP. Significant decreases in GSH content were observed in heart, liver, and testes only at 1716 ppm. Additional measurements were taken to investigate DCP distribution and potential indicators of acute toxicity. DCP was not present in the blood of animals 2 h after exposure to 955 ppm DCP or less. Serum lactate dehydrogenase activity was affected only at the highest exposure concentration, 1716 ppm DCP. Lung weight, measured at 2 and 6 h after exposure, did not differ from control for any of the exposure levels. This information demonstrated the importance of nasal tissue GSH in the metabolism of at least low levels of DCP. It also suggests the complexities involved with in vivo defence against inhaled DCP.