Acute nephrotoxicity of 1,1-dichloroethylene in the rat after inhalation exposure.

A renal toxicity of 4 h inhalation exposure to 1,1-dichloroethylene (vinylidene chloride; VDC) was studied in male Sprague-Dawley rats. Kidney wt./body wt. ratios, serum urea nitrogen and creatinine levels were significantly increased 24 h after exposure to 250 ppm or more of VDC. Histopathologic examination by light microscopy of hematoxylin and eosin (H&E)-stained sections revealed severe tubular necrosis with calcium deposits at the higher exposure concentrations. Specific staining for calcium oxalate was negative, indicating that biotransformation of VDC to oxalate is probably not responsible for its nephrotoxicity. Pretreatment with polychlorinated biphenyl (PCB) induced the level of renal cytochrome P-450. Phenobarbital (PBT) pretreatment did not alter the renal P-450 level, but both PCB and PBT pretreatments antagonized VDC nephrotoxicity. These pretreatments have also been reported to antagonize VDC-induced hepatotoxicity. In summary, inhalation of VDC is nephrotoxic in the rat; the mechanism of nephrotoxicity does not involve calcium oxalate formation, and the magnitude of nephrotoxicity does not correlate directly with the total amount of renal cytochrome P-450.