Acute effects of cadmium on the spot Leiostomus xanthurus (teleostei): Tissue distribution and renal ultrastructure

Abstract

Spot (Leiostomus xanthurus) were exposed to 1, 5, 10, 15, and 25 ppm cadmium chloride for 48 h. Analysis by atomic absorption spectrophotometry showed that cadmium accumulated mainly in the liver, followed by heart, gut, kidney, and gill. Brain and body muscle did not concentrate the metal. Electron microscopy showed that the proximal tubule cells were severely affected by cadmium levels of 10, 15, and 25 ppm. The proximal tubule cells exhibited responses that ranged from an increase in heterogeneous bodies to epithelial desquamation. Mitochondria of degenerating proximal tubule cells showed changes similar to metal‐poisoned mammalian kidney cells. Some mitochondria were contracted and dense while others were swollen with granular matrices and focal electron densities. In exposures of 25 ppm, Bowman's space of the renal corpuscle was swollen and often contained cellular debris. This study showed that after acute exposure to cadmium the metal accumulated mainly in visceral organs of the spot and at levels of 10 ppm and greater resulted in severe damage to proximal tubule cells of the kidney.