Chlorotrifluoroethylene nephrotoxicity in rats: a subacute study

Area of Science:

• Toxicology
• Environmental Health
• Renal Physiology

Background:

• Chlorotrifluoroethylene (CTFE) is a nephrotoxin.
• Understanding CTFE's effects on kidney function and adaptation is crucial for occupational safety.

Purpose of the Study:

• To investigate the toxic effects and adaptive responses of male Fischer-344 rats to repeated inhalation exposure of CTFE.
• To assess kidney damage and functional changes following CTFE exposure.

Main Methods:

• Male Fischer-344 rats were exposed to CTFE (395 ppm) for 4 hours daily over 5 days.
• Parameters monitored included water intake, urine osmolality, urinary lactic dehydrogenase, plasma creatinine, urea nitrogen, and urinary/serum fluoride levels.
• Kidney tissue was examined for necrosis and regeneration.

Main Results:

• Acute CTFE exposure caused diuresis, increased water intake, decreased urine osmolality, and elevated kidney/serum markers.
• Repeated exposures led to a decline or normalization of these parameters, suggesting adaptation.
• Histopathology revealed coagulative necrosis in proximal tubules, with regeneration evident by day 3, and minimal further necrosis.
• Increased urinary and serum fluoride indicated CTFE metabolism.

Conclusions:

• Rats exhibit adaptation to repeated CTFE inhalation exposure.
• Adaptation may involve changes in CTFE metabolism, disposition, or developing resistance in regenerating renal tissue.