Toxic effects of nonadecafluoro-n-decanoic acid in rats.

Nonadecafluoro-n-decanoic acid (ND-FDA) has a single dose ip LD50 of 41 mg/kg and causes anorexia and a wasting syndrome. NDFDA also appears to affect lipid metabolism although the metabolic fate and mechanism of action are not known. Control rats were pair fed with rats given 50 mg/kg. Body weights and food consumption were measured daily; body and organ weights, tissue histopathology, and hematological and clinical chemistry parameters were determined at 4, 8, 12, 16, and 30 days postdosing. Liver samples were obtained for determining cholesterol, cholesterol esters, phospholipids, total lipids, fatty acid ratios, and NDFDA. The rats became anorectic within 4 days and did not resume feeding for 10-12 days, losing about 40% of their body weight. There was a decrease in serum protein; total liver protein decreased and there was an increase in measured fatty acids except for stearic. Liver to body weight ratios of dosed rats were twice those of control rats since absolute liver weights in dosed rats remained constant during the weight loss period. The most striking histopathological change was seen in the liver with a uniform persistent cellular swelling at all times. Separation of the lipids by thin layer chromatography indicated that NDFDA was present in the most polar fraction. There also were fatty changes in the proximal tubular epithelium of the kidneys.