Submitted to: U.S. FDA Public Master File No. 5590
Publication Type: Popular Publication
Publication Acceptance Date: May 15, 1996
Publication Date: N/A
Interpretive Summary: Copper sulfate is used as a disease treatment in fish production. The U.S. Food and Drug Administration does not recognize copper sulfate as an approved chemical for this purpose therefore it is unlawful for fish producers to use copper sulfate. Part of the concerns expressed by FDA relate to the possibility that exposure to copper sulfate might result in high concentrations of copper (a heavy metal) accumulating in the edible portions of the fish. This study was to gather information about the potential human danger associated with consumption of fish that had been exposed to copper sulfate. Channel catfish were exposed to waterborne copper sulfate and then tissue samples were examined for copper content. There were no changes in copper concentrations in any fish exposed to many time the normal dosage of copper sulfate. This means that there is no hazard to human consumers of catfish exposed to copper sulfate.
Technical Abstract: Channel catfish were exposed ato 1.7, 2.7, or 3.6 mg/L of waterborne copper sulfate for a period of 10 weeks. Before, during, and after exposure samples of axial muscle and liver were collected and analysed by graphite furnace atomic absorption spectrometry for copper content. Continuous exposure of channel catfish to waterborne copper sulfate did not result in uptake and retention of copper in edible muscle. No dose or gender related tendencies were observed. Significant dose and gender related accumulation of copper in liver tissue was observed. Greatest dose and gender related effects were in males in the highest exposure group. Copper concentrations in livers of unexposed catfish did not change during the study. Copper concentrations in all exposed groups returned to normal 6 to 8 weeks after exposure was discontinued. Exposure of channel catfish to copper sulfate should pose no hazard to the human consumer.