Long-term exposure of rats to perchloroethylene, with and without a post-exposure solvent-free recovery period: effects on brain lipids.

The effects of perchloroethylene were studied in the rat brain after continuous exposure for 90 days at 320 ppm. Animals were also allowed after exposure to recover in a solvent-free atmosphere for 30 days. Lipid and fatty acid compositions were studied in particular. Changes were observed in the fatty acid pattern of ethanolamine phosphoglyceride in the cerebral cortex. Fatty acids 18:0, 20:1 (n-7) and 20:4 (n-6) were decreased while very-long-chain polyunsaturated fatty acids were increased. Most fatty acid changes were normalized during the 30 days post-exposure solvent-free recovery period with the exception of the minor fatty acid 20:1 (n-7). However, the previously unchanged fatty acid 18:1 was found to be decreased after the recovery period. Cholesterol was also decreased at this time and a tendency to reduction of myelin-enriched lipids after exposure to perchloroethylene might indicate a persisting loss of myelin membranes.