Levels of heavy metals and vitamin C in deformed thornfish found in thermal waters and effect of vitamin C on deformation of thornfish

Normal and deformed thornfish Terapon jarbua were collected from waters near the outlet of a nuclear power plant in northern Taiwan from June to September 1994. The levels of vitamin C and heavy metals and the ratio of hydroxyproline/proline in the fish were analyzed. The results indicated that the levels of heavy metals (Zn, Cu, Sn, Pb, and Cd) were not significantly different between normal and deformed fish. But the level of vitamin C and the ratio of hydroxyproline/proline in the deformed fish were lower than those of the normal fish. Thornfish were further separately cultured at 28, 32, and 36 degrees C, and fed a diet without vitamin C-supplement. Deformed fish appeared at 36 degrees C only, but this did not occur when fish were fed a diet with vitamin C-supplement. Therefore, deficiency in vitamin C might be a cause of deformed fish found in waters near the nuclear power plant.