Elimination of copper from Cu‐contaminated fish by long‐term exposure to EDTA and fresh water

Abstract

The changes of the Cu and Cd concentrations in the bodies of the Cu‐contaminated fish exposed for long periods to fresh water and EDTA were determined.

The fish exposed to Cu‐containing water for 90 days (Cu‐contaminated fish) had 3.2, 2.7 and 1.7 times the Cu content for viscera, gills and other parts in the 0.01 ppm Cu group compared with fish at the beginning of the experiment, and had 11.3, 3.3 and 2.5 times for viscera, gills and other parts in the 0.05 ppm Cu group, respectively.

The fresh water and EDTA treatment for 90 days in removing heavy metals from Cu‐contaminated fish tended to reduce the levels of Cu in the fish as the almost equal to those of the fish at the beginning of experiment.

After the fish had been kept for 90 days in Cu‐containing water, the Cd content had also increased in the three parts of fish. Treatment with complexan or fresh water after the accumulation of Cd had an effect on the decrease of Cd content in the bodies of the Cu‐contaminated fish.

Key words:

• Reduction of metal toxicity
• EDTA
• Fish
• Copper